04-3-004      Brown, Wyatt

Investigations to Increase the Shelf-life of Cilantro and Selected Vegetables

California produces over 50% of the vegetables consumed in the U.S. and is also a major grower of herbs. The goal of the proposed research is to increase the shelf-life and shipping ability of pre-cut cilantro, broccoli and cauliflower florets, and whole parsley.  Work will include the modified atmospheric packaging of cilantro and parsley using superatmospheric levels of oxygen and carbon dioxide, a recent innovation in postharvest technology; temperature studies to identify sources of heating of broccoli florets when stored and shipped in large, 40 lb bags intended for food service; investigation of an in-package cooling system for 40 lb bags of broccoli florets utilizing solid carbon-dioxide pellets, also a unique approach; studies of broccoli floret temperature as modified by carton design; and studies using ozone, antioxidants, and anti-browning agents to extend the shelf-life of cauliflower, cilantro and parsley.  Factors to be evaluated include film type, temperature, antioxidant, anti-browning agent, ozone efficacy, superatmospheric oxygen and CO2 levels and carton design.  Economically, the impact of this series of studies should be far-reaching.  Ozone has garnered much attention lately as a possible replacement for chlorine.  The results of these studies should contribute to the literature on ozone and its potential uses in the fresh vegetable and herb industries.  Likewise, antioxidants and anti-browning agents continue to play significant roles in food processing.  The proposed research would indicate the potential for these compounds with vegetables and fresh herbs and would potentially help position California to compete even more strongly in the market place.  If successful, the research with solid carbon-dioxide pellets will solve a recurring problem for a number of grower/shippers in California and will potentially allow rapid expansion of the pre-cut broccoli market.  Likewise, no research has been published to date investigating the effects of superatmospheric levels of oxygen and carbon dioxide on fresh herb shelf-life and quality.  As initial results with cilantro indicate a positive effect, this research also has the potential to increase the quality, shelf-life and market share not only for this product but for other herbs as well.

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04-3-005      Burt, Charles

Canal Automation Optimization

This research will address the focus area: Irrigation Management and Technology, and specifically emphasizes the first sentence in the ARI description of this area:  “Demands upon…California’s aging conveyance infrastructures will only increase as we approach the year 2020.”

The Irrigation Training and Research Center (ITRC) has developed improved control algorithms and has worked with commercial integrators and irrigation districts in numerous field applications.  ITRC has participated in more canal automation projects than any other university or company in the U.S.  Despite our tremendous advances, we still encounter two significant roadblocks that prevent smooth and simple implementation in the field.  This research will eliminate or decrease the size of these two roadblocks.  The roadblocks are:

1.            There is a lack of “packaged”, standardized control programs that can be easily placed into field Programmable Logic Controllers (PLC's).  Such packages must be developed to eliminate the errors and excessive programming time that are the norm in today’s field implementations.

2.            Our unsteady flow canal simulation programs (ITRC uses the world’s best such programs) still do not adequately simulate some of the hydraulic details close to the canal control structures.  We must do more field measurements of the feedback/response process in canals for which we have implemented automation.  Those detailed, actual responses of canals to the control algorithms can then be analyzed to develop better rules for tuning controllers.

The importance of this is basic and essential.  In order to properly manage the scarce resource of water, irrigation districts (serving over 8 million irrigated acres in California) must be able to convey and deliver that water to farmers in a timely, flexible, and well-controlled manner.  Proper automation of canal check structures and pumps is a key element of moving irrigation from art to science.  At this moment, perhaps only 5% or less of canal structures are automated in California; speeding up and simplifying the modernization process is the goal of this research.

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04-3-010      Farkye, Nana

Development of Process Queso Fresco

The goal of this project is develop a method for the manufacture of process cheese products from fresh Hispanic soft cheeses using Queso Fresco as prototype. With an increase in Hispanic population in the U.S., and in particular, California, there has been an increase in production and demand for Hispanic cheeses. Most of the Hispanic cheese manufacturers are relatively small and not automated, leading to occasional inconsistencies and loss of product fines during manufacture and economic loss to manufacturers. Large cheese plants that manufacture commodity cheeses such as Cheddar, Mozzarella, Jack, etc, save curd fines, cheeses that are out of specification, and returned cheeses that are salvageable for process cheese manufacture. Queso Fresco is an unripened soft cheese with high pH and thought not to melt. However, by adjusting the pH of the cheese in a cooker, and applying melting salts, Queso Fresco can be used in process cheese making. Technologies for the manufacture of process cheese products from Queso Fresco are not available. If it can be demonstrated that good quality process cheese products can be made from Queso Fresco, Hispanic cheese manufacturers would be able to minimize their losses by converting curd fines, cheeses that are out of specification and return cheeses into more stable process cheese products.

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04-3-012      Jaster, Edwin

Evaluation of Quality, Quantity and Timing of Colostrum Feeding on Immunoglobulin G1 Absorption in Jersey Calves

Inadequate or improper colostrum feeding and management cause a significant portion of the calf mortality on U.S. dairy farms. Colostrum is the secretion from the mammary gland for the first 24 hours after calving. Total solids composition of colostrum is 21- 27 % compared to 12 -13% in whole milk. In addition, colostrum contains high levels of immunoglobulins(Ig), which play an important role in establishing passive immunity in the young calf. There are three types of Ig in colostrum of dairy cattle: IgG, IgM, and IgA, of which IgG accounts for 85-90%. Additionally, there are two isotypes of IgG: IgG1 and IgG2. These Ig work together to provide the calf with passive immunity (immunity provided by the cow and not synthesized by the calf) until the calves own active immunity develops. This passive transfer starts to decline at approximately 12 to 23 hours after birth and ceases on average at 24 hours. Insufficient serum IgG concentrations in calves (less than 10 g/ml by 48 hours) result in a condition called failure of passive transfer (FPT) which contributes directly to a higher rate of calf mortality.
Little research has been conducted, especially with Jersey calves, comparing serum immunoglobulin G1 when colostrum with controlled concentrations of either high and low amounts of IgG1 is fed during the first 12 hours after birth. The experiment proposed will be conducted at the Cal Poly University Dairy Farm (San Luis Obispo, CA). Additionally, timing of feeding will be examined. Although studies in Holstein calves have been done with feedings from birth through 12 hours, in single or multiple feedings, this has not been replicated in Jersey calves. This study will examine the serum IgG concentrations of calves following ingestion of colostrum immediately after birth with and without a second feeding at 12 hours.

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04-3-013      Jimenez-Flores, Rafael

Early Detection of Spores and Spore Formers Using PCR and Chemiluminescence in Commercial Dairy Powder Samples

We are currently developing nucleic acid probes for the specific detection of early expression genes in contaminating Bacillus turingiensis and their spores. This development started in part thanks to a previous project funded by ARI, which allowed us to create the DPTC spore collection from strains found in milk powder.
The target gene, or family of genes, in the Bacilli are named Ger genes, of which GerC3 seems to be the one with widest distribution among the spore-forming organisms that contaminate milk powder and other foods. Further development of this technique can be applied for the detection contamination of foods by these organisms rapidly and very sensitively. I have been granted funding by the DOD through the C3RP to keep developing these probes towards early detection in germination of a surrogate model for B. anthrancis. The procedure funded by DOD focuses on a single microorganism as a model, and most of the development is made in a model system that does not represent that of the food environment (that environment mimics weaponized spore situation). Therefore, the logical extension of objectives and focus of this request is to apply the same procedure in samples that have an agricultural commercial application and relevance. This will further increase the value of the experiments, the learning experience for the students, and the practical utility to our partners by the evaluation of their commercial samples.
The objectives of this work are to deliver the following:
· In-depth information regarding the usefulness, capabilities and limitations of the procedures generated for the RNA-based rapid early germination detection of spores in foods.
· A procedure that can detect early germination on the most abundant spore forming species in dairy foods, such as B. licheniformis, B. subtilis, B. pumilus and others from the DPTC spore culture collection.
Relevant microbial information to the producer and processor of foods on their process regarding spore contamination and risk.

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04-3-014      Koutsos, Elizabeth

Interactions Between Poultry Health and Nutrition

Dietary incorporation of nutrients that modulate immune responses may be used in animal production systems to promote health and well-being while maintaining growth and production. As growth-promoting antibiotics are removed from animal diets, producers must find alternate strategies that promote optimal immune responses in production animals. Two nutrients that are of major interest to commercial poultry producers as potential immunomodulatory agents are copper and carotenoids.
Copper (Cu) is an essential mineral that is routinely supplemented in commercial poultry diets at higher levels than are required to prevent nutrient deficiency, since increased dietary Cu is associated with enhanced performance and reduced disease susceptibility. However, the mechanism by which Cu modulates immune responses is unclear, as is the optimal level of dietary Cu inclusion. Additionally, recent research has demonstrated that the source of dietary Cu can have a dramatic impact on performance of poultry. Therefore, the effect of two Cu sources will be examined, at several levels of dietary inclusion, on immune parameters in growing broiler chickens.
Carotenoids are lipid-soluble compounds that provide pigmentation and antioxidant and immune functions. While it has been demonstrated that carotenoids modulate mammalian immune responses, little research has been conducted in poultry despite the fact that commercial poultry are routinely fed carotenoids to enhance product pigmentation (e.g., egg yolks and poultry meat and skin). Recent data demonstrate that maternal carotenoid status (i.e., level of carotenoids fed to the hen) determines the ability of the hatched chick's immune tissues to incorporate subsequently fed dietary carotenoids. This model provides direction for future research concerning carotenoid-based immunomodulation, and may explain variability in previous data. Therefore, the effect of maternal (i.e., hen/egg yolk) and chick dietary carotenoid status on the immune response will be examined.
Data collected in these experiments will enable animal nutritionists to modulate immune responses more effectively with dietary Cu and maternal and/or dietary carotenoids, thus promoting animal health and well-being while maintaining high rates of efficient production. As antibiotic-free production becomes a reality, these types of strategies to maintain production and minimize disease and stress to animals will become a critical component of animal production systems.

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04-3-015      Mark, Walter

Development of Pitch Canker Resistant Stock of Monterey Pine, Ano Nuevo Stand

Pitch canker resistant Monterey pine planting stock from the Ano Nuevo Stand is needed for reforestation and ornamental planting throughout California. Susceptibility screening for pitch canker was conducted in the Ano Nuevo stand from 1999 through 2002 provides a base for collecting cuttings, and rearing seedlings from Monterey pine trees. In addition, trees along the Highway One Cal Trans right-of-way have undergone initial screening for resistance to pitch canker. The Cal Trans trees can be utilized to develop resistant stock of unknown genetic origin for planting as ornamentals where no native Monterey pine populations exist. These should not be utilized in areas of native populations due to the potential for genetic contamination. This project would be conducted in the Ano Nuevo Stand, Swanton Pacific Ranch, Highway One Cal Trans right-of-way in Santa Cruz County, Pebble Beach Corporation, and at California Polytechnic State University, San Luis Obispo.
Preliminary inoculation testing has been conducted on approximately 70 trees in the Ano Nuevo Stand and another 30 along Highway One in cooperation with the California Department of Forestry and Fire Protection and the U. S. Forest Service. Seed has been collected and seedlings grown for common garden tests, early resistance challenging for further determination of resistance, and out planting in conjunction with the Monterey Pine Management study being conducted on the Swanton Pacific Ranch. Cuttings for rooting need to be collected from trees determined to be resistant to Fusarium circinatum. These will be utilized to produce hedging stock for propagation of clonal resistant stock. Techniques will be developed to produce clonal stock from needle fascicles and meristems in tissue culture.
This proposal seeks funding to 1) rear Monterey pine seedlings for use in further studies on the resistance to pitch canker, 2) collect and root scions from the Ano Nuevo Stand and Cal Trans right-of-way trees, 3) develop hedge stock at Swanton Pacific Ranch for production of resistant clonal planting stock, and 4) produce tissue culture stock of resistant trees for planting outside the Zone of Infestation. Funding is sought to support this effort in an ongoing way over the next two years.

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04-3-017      Olabi, Ammar

Sensory Properties of Whey Cream-based Buttermilk and their Relation to Super Critical Fluid Extraction

This work focuses on defining and understanding the sensory characteristics of whey cream buttermilk (WCBM) processing after being treated by supercritical CO2. Using descriptive analysis and instrumental measurements of different indicators of lipid content and protein degradation, we will examine the effects of supercritical fluid treatment and storage variables on WCBM samples manufactured at DPTC and compared to industrial samples. This information is necessary for developing novel ingredients from an industrial by-product with nutritional advantageous properties.

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04-3-018      Piirto, Doug

Management Strategies and Understory Growth Response in Young-growth Sequoia Stands at Mountain Home Demonstration State Forest

The proposed study integrates a long-term study on silviculture treatments that was first implemented in 1989 by the California Department of Forestry and Fire Protection (CDF) with a new wildlife management study. The wildlife management study will involve forest raptors (i.e. birds of prey), which will be conducted in the same area as the initial study in giant sequoia stands at Mountain Home Demonstration State Forest (MHDSF).
The proposed study has two objectives: 1) to address the effects of silviculture techniques (i.e. prescribed burning and thinning) on understory vascular plants and shrubs within second-growth giant sequoia stands over the last twelve years. The study will examine if thinning a stand, thinning and burning a stand or no treatment at all affect the diversity (e.g. plant species richness) of understory plants and shrubs. The second objective involves expanding the nature of the study: 2) to examine the relationship between forest raptor abundance, and the existing vegetation mosaic (i.e. stand structure and composition) created by different silviculture treatments. This is of interest, especially by the CDF, in knowing the current distributions of forest raptors due to increased timber harvest regulations and concern for sensitive wildlife species in California. State agencies, like the CDF and the Department of Fish and Game have expressed a need for more documentation on forest raptors that use coniferous forests in the Sierra Nevada as part of their home range.
This study would be beneficial to agriculture and natural resources because it will provide new information on the influence of silvicultural techniques and prescribed fire on understory vegetation in the giant sequoia ecosystem. This on-going study would provide new and useful information to the scientific community, state agencies, and the general public because of the current restriction on initiating a stand manipulation study in giant sequoia groves. Further, this study will provide additional funding for the new wildlife management phase of the project. This new addition to the study would be beneficial to agriculture and natural resources because it will provide initial habitat data on these elusive forest raptors in the southern most portion of their geographic range in a unique ecosystem.

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04-3-019      Steinmaus, Scott

Development of a Predictive Model for Arundo donax Based on Climate in California

Economic losses associated with plant invasions have been estimated to be over $123 billion annually in the U.S., in addition to immeasurable ecological and aesthetic losses. Exotic species invasion into natural ecosystems represents among the most significant threats to biodiversity and ecosystem stability. Scientists and land managers agree that the most effective management protocol is prevention, prediction, and control. Our objectives will focus to build on the predictive models that we have already developed for several invasive plant species. We will begin our research by quantifying the thermal and moisture preferences and constraints for Arundo donax (giant reed, hereafter referred to as Arundo) as this species represents one of the most aggressive and impacting invasive species in California riparian habitats. We plan to improve the resolution of the climatic database that drives the predictive models, CLIMEX and DYMEX, as well as determine and incorporate the characteristics of Arundo into our own growth simulations. The output from these models will predict the locations in California most susceptible to Arundo invasion but have not yet been exposed to the species. Land managers can then be alerted to the susceptible sites under their control, so that prevention measures can be initiated. We will also develop a population dynamics model for Arundo using information generated by the biological and CLIMEX portions of this project using DYMEX to predict the rate of spread into new locations throughout California. We will apply the model to infested locations to determine the potential for Arundo populations to actively spread from their current locations. Developing the high-resolution climatic database will facilitate the predictions of any invasive species that might infest or spread in California. Developing the climatic preferences and constraints for Arundo will serve as a protocol for determining the same parameters for many other invasive species. A stand-alone thermal time model will be parameterized as a result of this project, which will allow land managers to predict when Arundo will be at a susceptible stage for control at their location. This will be quite useful as Arundo typically grows in areas that are difficult to access and monitor.

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04-3-020      Williams, Doug

Improved Utilization of the Biogas from the Cal Poly Dairy Covered Lagoon

This project proposes to modify the existing covered lagoon system by heating it with the waste heat from the existing microturbine generator. This will result in more biogas production which will in turn result in more electrical production. In collaboration with Southern California Gas, the biogas will be supplemented with natural gas to allow 24/7 operation of the microturbine at full capacity to more fully take advantage of the energy production potential of the microturbine.
Also to be explored is the treatment of other organic wastes such as dairy processing wastes from the adjacent Dairy Products Technology Center. This will also result in more biogas production from the covered lagoon. At present, the covered lagoon is producing only 2000 cubic feet per day which provides enough fuel to operate the microturbine for 6 hours per day and at 20 KW, or 2/3 of the full capacity. This results in a net electrical production of approximately 95 kwhrs per day, worth less than $10 per day and 3,650 per year. Additional biogas and/or natural gas will increase the operating time of the microturbine to over 8000 hours per year at 30 KW for a total of 240,000 kwhrs per year worth $24,000. Utilization of the waste heat in the microturbine exhaust, averaging approximately 200,000 Btu/hour, for such things as water heating and absorption cooling will result in further benefits equivalent to 50 therms of natural gas worth $25 per day, and $9,000 per year.   

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05-3-003      Burd, Matt

Pregnancy Rates Using Cooled, Transported, Cryopreserved Equine Embryos

The use of embryo transfer in the equine industry has gained momentum over the last decade.  The largest limitation to the widespread acceptance of embryo transfer remains the cost associated with the procedure.  Maintenance of a recipient herd continues to be one of the most costly aspects.  Recently the transport of cooled embryos has gained popularity as this circumvents the expense of smaller breeding facilities maintaining a recipient herd.  As the practice of using cooled transported embryos grows, interest has also grown as to the feasibility of cryopreservation of these cooled transported embryos for later use.  The ability to stockpile frozen embryos in a central facility would greatly reduce the expense of embryo transfer by allowing a recipient herd to be utilized on a more consistent basis.  This project would explore the possibility of successfully freezing cooled transported embryos.

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05-3-004      Nicholson, Lisa

Tailored Parent Nutrition Education and Community-Based Learning

The goal of the proposed project is to create nutrition education materials targeted to low-income parents of children in Head Start.  Qualitative data will be collected and assessed to understand the needs and disparities of the target populations.  Based on the outcomes of the values, knowledge, and nutritional choices, nutrition education materials will be tailored to include the attitudes and cultural values, as well as the barriers and benefits perceived by these parents towards taking healthy nutrition actions.  The overall design is to use information from structured interviews and focus groups to tailor nutrition education approaches to match methods and materials to learner preferences.  Information from the focus groups will be used to determine the message content, the cultural meanings, and the most effective methods to encourage applying this nutritional information.  University students will participate in creating nutrition education materials.

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05-3-005      Wong, Jeff

The Cloning of Barren Stalk1 in zea mays by Transposon Tagging

Zea mays (corn) is an important cereal and forage crop around the world and in the United States.  Corn has been studied extensively.  The development of the tassel (male inflorescence) and ear (female inflorescence) has been studied extensively.  Several mutants in corn have been characterized that lead to abnormal development of the tassel and ear.  Barren Stalk1 is a recessive mutant of corn that has no tassel branches, spikelets, tillers or ears.

 A targeted mutagenesis study will be initiated. Plants containing a transposable element and the barren stalk1 gene will be screened for the mutant.

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05-3-007      Beckett, Jon

Interactions between b-Adrenergic Agonists and Growth Promoting Implants on Performance and Carcass Characteristics in Holstein Steers

Since 1950, performance enhancing products have been used to increase the productivity of beef production.  These products enhance growth and efficiency, resulting in lower costs for consumers.  In addition, food safety is improved by decreasing animal health problems, thereby decreasing antibiotic use.  The most common performance enhancing product is the class of steroid hormones.  The use of growth-promoting implants in the US is widespread – an estimated 95% of cattle receive growth-promoting implants.  Although implants dramatically increase average daily gain (~10%) and feed efficiency (~15%), there is evidence that implants decrease quality grades (Prime, Choice, Select and Standard) and tenderness of the meat.  The most recent entry into the cattle performance enhancing products is a b-adrenergic agonist (bAA), Ractopamine.  The product gained full FDA approval in January, 2004.  This product is the first of the class of bAA to be introduced to the US market.  Cattle fed Ractopamine for the 28 days immediately prior to harvest demonstrate significantly improved muscling and weight gain over non treated controls.  However, studies conducted on more aggressive bAA (not FDA approved) indicate that these products may compromise quality grades and tenderness.  The endocrine cascade stimulated by Ractopamine is separate from that of the growth-promoting implants.  Thus, the effects should be additive, if not associative.  However, no studies have investigated the interaction between growth-promoting implants and bAA.  While the vast majority of the cattle fed in the US are of traditional beef cattle background, there is a large number of steers that enter feedlots as byproducts of the dairy industry.  Indeed, California places approximately 600,000 Holstein steers in feedlots annually.  These cattle offer much greater genetic consistency than cattle of traditional beef genetics.  Therefore, treatment effects will be more evident.  The objective of the proposed research is to test the interaction between an FDA-approved bAA and commercially available growth promoting implants.  Specifically, the following responses will be measured: (1) effect on growth and efficiency characteristics, (2) influence on quality grade, yield grade, dressing percent and ribeye area, and (3) determine the interactive effect on meat tenderness. 

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05-3-009      Burt, Charles

Defining the Unique Characteristics of Variable Frequency Drive (VFD) Motors and Pumps for Agriculture

Typical in-field pump efficiencies that have been documented by ITRC for irrigation districts are 57 % (based on 1028 measurements in 2001-2003) and 51% for farm irrigation pumps (based on 2893 measurements in 2001-2003).  Efficiencies should ideally be in the 75% range, so this difference represents a huge waste of energy. 

Variable frequency drive (VFD) controllers, which enable standard electric motors to change their speed depending upon the pressure or flow rate requirement (in contrast to regular motors that only run at a single speed such as 1800 RPM) are becoming popular in many applications because of control advantages and purported energy savings.  ITRC already has extensive experience in irrigation district-related VFD applications. 

In our work, we have identified two general knowledge gaps for VFDs that inhibit our wise use of this technology:

1.   The characteristics (efficiency and torque) of standard electric pump motors, when they are converted to VFD units using special controllers.  The understanding of pump efficiency is good at different speeds, but we are simply guessing about the motor efficiencies. 

2.   Good procedures to define critical resonance of VFD pump systems.  That is, at certain revolution speeds (RPMs) pumps can vibrate violently and cause serious damage to people and equipment.  Before putting a VFD controller on a pumping unit, we do not know if there will be problems. 

This project will do the following:

1.   Research procedures and equipment to properly evaluate electricity input/output on VFD controlled motors attached to pumps.

2.   Develop a state-of-the-art test bench for motor/pump VFD combinations up to 100 HP, using new electronic technology to measure flow, input HP, Power Factor, Resonance, Motor HP, motor torque, and pressure.

3.   Using vibration analysis equipment, define procedures to test pump assemblies for critical resonance before they are installed in the field.

4.   Test at least 50 pumps in the field for vibration characteristics, to determine how serious the problem of vibration can be.

5.   Use 5 “typical” pump/motor assemblies as test cases to develop guidelines on procedures to better estimate efficiencies of proposed VFD conversions.

6.   Publicize the information in various publications, workshops, and the ITRC web page. 

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05-3-011      Dicus, Chris

Tradeoffs in Community Benefits Versus Fire Risk in Wildland/Urban Interface Forests

Urban sprawl threatens both agricultural lands and natural resources.  Where new development occurs, there is often a great loss in canopy cover of native woodlands and shrublands, which leads to a decrease in social and environmental benefits such as carbon sequestration, stormwater absorption, and energy conservation.  To counteract the loss of vegetative cover, there has been a swell of recent interest to reclaim lost canopy cover by replanting native vegetation.  However, as millions experienced in October 2003, the same native vegetation that supplies biological and social benefits also is prone to burn with great intensity and destruction.  Therefore, there is a critical need to assess the tradeoffs in benefits derived from vegetative canopy versus its potential to facilitate destructive wildfires. 

This study will investigate the tradeoffs between community benefits derived from adding tree canopy coverage in the wildland/urban interface verses the inherent risk of wildfire associated with this additional vegetation.  Two GIS-intensive software packages will be utilized in this analysis.  CityGreen, used to assess community benefits, translates digital images of canopy coverage into real dollar savings in forms such as cooling costs, stormwater runoff and air pollution removal.  FARSITE will be utilized to assess potential fire behavior across the landscape for multiple combinations of fuels, weather, and topography.  The results of this research will aid community planners in developing the best strategy for managing vegetation in California’s wildland/urban interface.

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05-3-012      Dietterick, Brian

Determination of Event-Based Suspended Sediment Export From Little Creek , Swanton Pacific Ranch

Scientifically-defensible watershed study designs, such as paired and nested, have been used successfully to document event-based suspended sediment yields from actively managed forested watersheds.  To date, no such studies exist further south than the Caspar Creek experimental watersheds in northern California.  Studies similar to Caspar Creek are being looked upon by the timber industry and regulatory agencies to assess the effectiveness of forest practice rules in protecting water quality from adverse suspended sediment impacts.  Yet, there is a great deal of uncertainty in the ability to calibrate these studies in typical calibration periods of 4-5 years in the landslide-dominated coastal mountains and widely variable climatic conditions found south of San Francisco.  This study on the Little Creek watershed is designed to determine the magnitude of change that can be detected in the event-based suspended sediment response using a paired and nested study design during the pre-harvest period.  The dataset will analyze differences between stations for turbidity, suspended sediment concentration, and event load values using linear modeling techniques to test the significance of the relationships.  The results of the study will be used to not only document the variability in suspended sediment response experienced in this region, but also to answer the important question of whether paired and nested studies can be successful in this environment.  This study is aligned with the Agricultural Issues category, Natural Resources and Environmental Quality, as defined by the NRI.  The study meets the criteria of both priority research areas for this program by addressing suspended sediment export on forested watersheds currently undergoing anthropogenic management activities and increasing the understanding of these processes for the purpose of protecting water quality.

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05-3-016      Hendricks, Bill

Economic Impact of Visitors to Oceano Dunes State Vehicular Recreation Area

The purpose of this study is to determine the economic impact of visitors to Oceano Dunes State Vehicular Recreation Area on local communities and the County of San Luis Obispo.  A secondary purpose is to examine the resource amenities that attract visitors to the park.  A previous study conducted at Morro Bay State Park, is to our knowledge, the first study to examine park visitor economic impact at a zip code level at a more finite level than county zip codes using the IMPLAN economic analysis model.  The study has garnered substantial attention locally and in the California State Park system for its applied research design (over 70% response rate) and results indicating a significant impact on the City of Morro Bay by visitors to the park.  The present study will continue this line of research in an off-highway vehicular area to further investigate the benefits of state parks to California’s economy and the tourism industry.  Analysis of the data from the two studies will also allow for a comparison of what may be two very different markets of park visitors that will assist state park managers in park planning, policy development, and management.

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05-3-018      Patterson, Keith

Winegrape Quality Separation Using GPS/GIS Technology

Many factors are responsible for final winegrape quality.  Factors such as site, variety, cultural practices, and irrigation strategies impact quality.  Within each vineyard, however, there can be great variation in soils, nutrient availability, water holding capacity and thus vine growth.  This variation in vine growth leads to differences in ripening and subsequent wine quality.  Vineyards, therefore, with variation farm to the “average” level of ripeness and quality.  This leads to less the optimum quality wine from vineyards.  This knowledge of variation has led to numerous vineyard projects that attempt to minimize differences and increase wine quality.  Research has consistently shown that the major differences in quality within a vineyard are due to different vine growth and fruiting patterns.  To date, the use of GPS/GIS has been limited to evaluating vineyards for stress levels and the movement of diseases and insects.  Limited use has also been employed to attempt to identify these different areas of vigor in order to change pruning practices and other cultural operations.

The purpose of this project will be to use aerial photography equipped with Normalized Differential Vegetation Index (NDVI) lens in order to identify different levels of vigor and growth within individual vineyards.  After these different areas have been identified, the GIS data will be loaded into a PDA that will allow researchers to go directly to vines showing differences.  Once these areas within vineyards have been identified, wine samples will be produced from each of the levels and compared for wine quality.

Our project will determine if it is possible to identify areas in vineyards that will produce superior wine.

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05-3-019      Plummer, Bill

Does the Appearance of Specific Proteins in the Male Reproductive System have a Relationship in Assessing Sperm Quality?

Semen analysis for fertility has traditionally been conducted by light microscope and used standards that relied strictly on what could be grossly observed about the sperm.  Essentially, a male could be considered fertile, but the only real information gained was what his sperm looked like.  No real knowledge of his fertility was known until he had offspring on the ground, which in the case of livestock could take up to a year.  The current proposal outlines a study which would build upon previous data and attempts to make an accurate evaluation, using proteins associated with defective sperm, of the fertility of a sperm without regard to its visual qualities.  This work ties together two different procedures: first, use of Computer Assisted Sperm Analysis (CASA or IVOS) to evaluate the motility parameters of the sperm which cannot be observed using just a light microscope and second, staining marker proteins on individual sperm and evaluating those sperm on whether they are or are not intact and therefore quantifying their fertility.  This project will be using bulls but the application is for all mammalian species.  Reproduction and fertility in cattle directly affects an industry that is valued at a minimum of $5 Billion/ year to the state of California.  Expanding to include all other large agriculture animal species will increase this significantly.

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05-3-020      Rice, Tom

Assessing Wine Quality Relative to Soil Types: A Study of Terroir

The world's greatest wines are almost always the result of a threefold synergy between grape variety, human input (in terms of choices about viticulture and wine making) and the terroir (here defined as the vineyard site, soil and microclimate).  Most studies of terroir have concentrated on the flavor components of the wine as related to the vineyard environment.  In this study, the soil and wine properties will be quantified to determine whether or not a relationship exists between them. 

This research will investigate the relationships between soil geochemistry (organic and inorganic soil components) and wine quality, as measured by the inorganic and organic constituents in the wines (at post-fermentation, pre-barrel stage) produced from Cabernet Sauvignon wine grapes. 

The vineyard and winery chosen for the research is the Carmody McKnight Estate Wines, located about seven miles west of Paso Robles, CA.  Past investigations at this vineyard show that Cabernet Sauvignon is grown in a north-south orientation across significantly variable soil types.  Therefore, this location will serve as an excellent research location, since the same wine grape variety is grown on differing soil types, all other factors being relatively equal.

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05-3-021      Styles, Stuart

Flow Rate Indexing Procedure (QIP) for Non-Standard Structures

This proposal is for Cal Poly Irrigation Training and Research Center (ITRC) to utilize new emerging technologies to assist California water agencies in improving their water management through the development of a rating procedure for non-standard structures.  Hydroacoustic instruments, one of the emerging technologies, can be utilized at numerous existing non-standard structures, which were not originally designed for measurement.  Developing a “rating” for a structure, or determining the flow characteristics, is difficult if the structure is non-standard, and in the past has required a tedious and expensive procedure.   

The use of advanced electronic flow meters could significantly reduce the time required and could also increase the accuracy of the rating curve.  Currently, there is no standard procedure for the use devices such as hydroacoustic flow meters in these types of applications.  Developing a procedure that can be used with emerging technologies to quickly rate an existing structure would allow for accurate measurement in situations that otherwise may be too expensive or time consuming, but nevertheless important for operations, environmental, or project planning purposes. 

To fully take advantage of this potential will require the development of standardized, field-tested procedures and widespread dissemination to water professionals throughout the state.  The ITRC is in a unique position to take advantage of in-house expertise, a proven track record of practical solution-orientated research, and numerous contacts with industry and water agencies. 

This project is targeted to align with the ARI Irrigation Management and Technology target area by evaluating a new and emerging irrigation technology.  The benefits of this project will be statewide in California as increasing demands for a limited resource have required all water users to better account for their water use.

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05-3-022      Tong, Phil

Use of Dairy Ingredients in Extended Shelf-life Dairy-Based Foods

Background:  Increasingly consumers demand high quality foods and beverages which have fresh taste but provide necessary convenience (good refrigerated or non-refrigerated storage life). Such convenience is also essential for food service establishments and vending occasions..  Such products are more amenable to meet expanding needs for better alternatives to sodas in school lunch programs also. In dairy based beverages achieving such extended shelf-life (ESL) properties is challenging because the thermal processes needed to extend shelf-life can destabilize the food system and cause undesirable viscosity changes, emulsion instability and/or excessive protein aggregation to result in poor texture (chalkiness), or actual product separation (creaming or sedimentation).  Such undesirable changes in product quality have limited broad development of high quality extended shelf-life dairy foods.  A better understanding of factors which contribute to stability or instability of dairy ingredients during extended shelf life processing (ultra-pasteurization (UP) conditions, or ultra high temperature (UHT) conditions are needed.  Such UHT equipment to conduct such studies is expensive and difficult for most universities to obtain. My group is fortunate that a grant (matching funds source) has been provided to purchase, set-up and operate the necessary equipment to conduct the proposed work in this CSU-ARI grant.   In addition, our group has specialized expertise in manipulation of mineral content of dairy based systems via use of membrane processing which we believe will be key to improving stability issues. 

Objectives:   The main objectives of this CSU-ARI research are to:  1) Assess the variability in ESL processing of a dairy beverages formulated with commercially available skim milk powder or modified skim milk powder (lactose and mineral reduced) or lab prepared ultrafiltered skim retentate; 2) evaluate the potential to use stabilizers and mineral chelating agents to improve ESL processing performance; 3) evaluate indirect or direct heating systems for ESL processing on product stability.   

Expected Use of Results:  The results of these studies will provide needed information to provide guidance to users of skim milk powder for extended shelf life dairy beverages.  The information will be communicated one on one via ongoing program activities in my group (e.g. DMI Dairy Hotline), website, and our annual dairy ingredients symposium and other scientific meeting venues.  This study will demonstrate to students importance of dairy chemistry and engineering principles using cutting edge food processing technology.

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05-1-010      Jimenez, Rafael

Development of Dairy Products Enriched in Milk Fat Globule Membranes and their Characterization Using Laser Tweezers

Considerable current research demonstrates the beneficial properties of milk and its components.  One of the least characterized and poorly processed constituents of milk is the milk fat globule membrane (MFGM).  This material is complex, containing proteins, lipids, oligosaccharides, phospholipids, glycolipids, glycoproteins, and other compounds with proven biological activity.  The MFGM contains perhaps one of the most important biological activities in milk in terms of human health.  Butter and cheese production, two of the most important fields in California’s agriculture, yield co-products such as buttermilk and whey where MFGM components are most abundantly found.  These components are functionally important as food emulsifiers and sources of highly active phospholipids, complex glycoproteins and lipids that regulate cell communication such as sphingomyelin.  However, the commercial importance of MFGM components has not been realized because of their poor keeping quality and their low concentration in the different co-products.  Furthermore, no clear characterization of their function has been made, nor data generated on their physical properties.

For the last two years, we have been working on developing ingredients with increased concentration of MFGM components and improving their keeping quality.  However, it has become evident that accurate and detailed information on the physical and chemical properties of these ingredients is essential for their commercialization. 

In this work we propose to study the physical, chemical and biological basis of these ingredients’ composition and properties.  The work will be carried out using novel techniques based on laser tweezers technology and compared to traditional methods of functionality assessment. 

A strong team has been assembled for the completion of the objectives.  Cal Poly DPTC scientists will be generating ingredients containing MFGM components, and will characterize these components with traditional procedures.  Dr. John Sharpe at Cal Poly Department of Physics has the required infrastructure and knowledge to set up a laser tweezers module.  Dr. Juan Fernando Medrano from UC Davis will contribute mammary epithelial cells that are fundamental for the understanding of the biological origin and activity of the membrane components.

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06-1-017      Mark, Walter

Spatial Modeling of a Biological Invasion: Landscape-level establishment and spread of Phytophthora ramorum in California

Biological invasions cause dramatic ecological changes around the globe.  Invasive species alter ecosystem processes, undermine biodiversity at multiple scales, and negatively influence 49% of all imperiled species in the United States.  One type of invasion that is occurring with growing regularity is the spread of non-native plant pathogens.  By killing host species that play key roles in forest ecosystems, invasive plant pathogens can dramatically alter forest community structure and genetic diversity of host populations. 

The emergence of the invasive pathogen, Phytophthora ramorum, has caused epidemic levels of a forest disease called “Sudden Oak Death” in coastal regions of California and southwest Oregon.  Phytophthora is a large genus of widely distributed water molds that cause many economic and ecological problems in agriculture and forestry.  More than 60 plant species are potential hosts, enabling P. ramorum to inhabit a variety of widespread forest types.  Among its host species, P. ramorum causes two forms of disease: lethal branch or stem infections, and non-lethal foliar and twig infections.  The lethal form of the disease kills several important trees, including tanoak (Lithocarpus densiflorus), coast live oak (Quercus agrifolia), black oak (Quercus kelloggii), canyon live oak (Quercus chrysolepis), and Shreve’s oak (Quercus parvula var. shrevei).  Except for tanoak, the pathogen does not seem to spread from these species.  In contrast, widely abundant foliar hosts such as bay laurel (Umbellularia californica) and tanoak can support the production of numerous dispersal spores on their leaves, which can be spread via rainsplash and wind, as well as on nursery stock, in stream water, and soil transported by vertebrates.  Establishment of this non-lethal form of the disease may play a key part in transmitting the pathogen and enabling it to develop persistent populations.

It is critical that we gain an understanding and ability to predict disease spread in order to develop effective strategies for detection, management, and prevention.  Spatial modeling of disease dynamics is an approach that is critically needed for developing a predictive understanding of factors that influence plant pathogen dispersal and infection processes.  Modeling enables integration of multidisciplinary information and provides a framework for repeatable, nondestructive experiments at broad spatial scales.  Spatial modeling can also be used to reconstruct past events and forecast future trends.  A variety of ecological simulation models (e.g. land cover change, forest succession and wildfire) have been successfully applied to facilitate a predictive understanding of a system’s behavior and structure under heterogeneous landscapes and environments.  However, few studies have developed spatial models of plant disease spread in natural systems because a multidisciplinary framework is needed to incorporate fine-scale processes of pathogen dispersal and survival into landscape-level models.

Spatial modeling of disease dynamics is also direly needed to assist in the selection of threatened sites for early-detection monitoring efforts.  It is essential to understand where and when P. ramorum will spread in order to effectively monitor the disease and manage threatened forests.  The regulatory process for P. ramorum will also benefit from such research.  Regulation of Phytophthora ramorum is taking place within California by the California Department of Food and Agriculture (CDFA), nationally by the Animal Plant Health Inspection Service of the US Department of Agriculture and internationally by several controls, which have imposed quarantines on California plant products.  The regulatory and quarantine efforts depend upon accurate mapping of the areas infested by P. ramorum.  Lacking accurate distribution information, quarantines tend to be broad scale to protect receiver sites and have a very negative impact on the California plant industry.

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06-3-003      Goldenberg, Marni

Understanding Longitudinal Outcomes of Wilderness Participation Using Means-End Analysis

Typically, means-end theory is used to understand consumer decision-making behavior.  Means-end theory specifically examines the linkages between the means (the service) and the ends (the consequences and values important to the individual).  Means-end theory links attributes (the physical aspect or characteristics to describe a service or product), with consequences (desirable or undesirable results), with values (end states that consumers are trying to achieve).  Previous research has used means-end theory to examine outcomes associated with ropes course and Outward Bound participation.  Outward Bound is a nonprofit, educational organization that utilizes an outdoor/natural resources based environment to provide groups of participants a wilderness adventure expedition.  This previous research expanded the use of means-end theory to uncover the outcomes associated with a multi-day outdoor adventure experience versus the one-day ropes course experience.   

Through this past research, it was apparent that more research needed to be developed.  This study will use means-end theory to examine long-term outcomes of outdoor adventure experiences.  There is a gap in the research on longitudinal studies related to outdoor adventures.  One of the results from the means-end research that examined Outward Bound experiences stated that participants experienced a value of transference.  This means that participants had a motivation to transfer the information they learned on the outdoor education course into their daily lives.   

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06-3-004      Beckett, Jon

Application of multiple marker, pre-implantation genetic testing of bovine embryos

In order to ensure a consistent supply of safe, affordable and high-quality animal based food products, producers of domestic livestock strive to improve genetic influences in their herds.  Increasing the genetic potential of sires has taken place for more than 50 years through artificial insemination.  With high-performing females, the collection of embryos gives producers the potential to increase selection pressure.  However, the most significant potential gains will be achieved through genetic testing.  Successful efforts to combine the reproductive biotechnologies with genomic techniques enable scientists to identify embryos carrying increased genetic potential for certain traits.  Recent advances in gene amplification enable investigators to use sex-specific probes to determine sex in only 1 cell removed from embryos.  The biopsy method has had increasing success in fresh and frozen embryos.  The limiting factor on performing multiple DNA tests on an embryo biopsy is the very limited amount of DNA available in each biopsy.  Recently, whole genome amplification has become a viable method of consistently and uniformly increasing the amount of DNA available from each biopsy.  The proposed research will validate the MDA method for more than 2 DNA tests, and develop a strategy for producing “designer” bulls for a California producer using a combination of embryo transfer and DNA testing.  Finally, a third single nucleotide polymorphism (SNP) has been discovered for m-calpain (a tenderness gene).  Briefly, cows with desirable genetics will be purchased by a coastal rancher.  The cows will undergo embryo transfer at Cal Poly, the embryos will be biopsied, DNA from embryo biopsies will be amplified using polymerase chain reaction (PCR) and presence of alleles for the multiple traits will be identified.  Recipient cows will be implanted with genetically tested embryos determined to have the desirable traits, i.e. bull calf with desirable m-calpain genotype.  The first objective of this study will be to develop laboratory protocols for the testing for more than one gene from a single biopsy.  The second objective will be to design primers for the 3^rd SNP for m-calpain, and the third objective will be to apply the preimplantation genetic testing technology to a California beef herd.

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06-3-005      Brown, Wyatt

Investigations into the Modified Atmosphere Packaging of Pre-cut Artichokes

California accounts for nearly 100% of the total U.S. production of artichokes.  Marketing problems with fresh artichokes include the high respiration rate of the buds, the tendency of the buds to discolor easily and for the discoloration to be dark and very noticeable.  The goal of the proposed research is to develop a viable modified-atmosphere (MA) package for pre-cut artichokes, that will maximize shelf-life while minimizing or eliminating unwanted browning.  The study will initially explore the use of antioxidants and antibrowning agents to control or alleviate tissue discoloration due to trimming.  Compounds to be tested include but are not limited to:  ascorbic acid, citric acid, erythorbic acid, the pyrophosphates, the carrageenans, and ethylenediaminetetraacetate (EDTA).  Compounds will be tested alone or in combination.  The use of surfactants and/or wetting agents to promote the efficacy of the compounds will also be investigated.  Concomitantly, tests will be run to assess bud respiration as affected by age, variety and season of harvest.  Respiration data will be used in the development of a modified atmosphere (MA) package.  Additional factors to be evaluated in developing the MA package will include film type, bud temperature in storage and at retail, and antioxidant and/or antibrowning agents.  Data to be collected during storage studies will include in-package levels of carbon dioxide and oxygen, film permeability to carbon dioxide and oxygen as affected by temperature, and changes in color (including discoloration) and weight of the artichoke buds.  Tests also will be run to investigate the effect of 1-methylcyclopropene (1-MCP) in reducing the rate of discoloration and/or senescence of packaged artichokes.  Economically, the impact of this series of studies should be far-reaching.  The proposed research seeks to test the efficacy of standard antioxidants/antibrowning agents  as well as novel compounds such as kappa- and lambda-carrageenans in preventing the browning of artichoke buds.  As artichokes discolor rapidly when cut or bruised, success in the area of research will have immediate impact to the artichoke industry of California which is seeking a means to successfully market pre-cut, ready-to-microwave artichoke buds.  Additionally, this research will indicate additional methods to prevent the discoloration of commodities such as pre-cut lettuce and apples.  A unique aspect of the research is to investigate the potential for 1- MCP to extend the shelf-life of artichokes.  As very little research has been conducted with vegetables and 1-MCP, the work proposed will further indicate the possible value of this compound to the vegetable industry, both nationally and within California, and should be of use in having this chemical registered for different vegetable commodities.

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06-3-007      Delmore, Robert

Effects of implants on physiological growth and carcass attributes in Holstein Steers

Since 1950, performance enhancing products have been used to increase the productivity of beef production.  These products enhance growth and efficiency, resulting in lower costs for consumers.  In addition, food safety is improved by decreasing animal health problems, thereby decreasing antibiotic use.  The most common performance enhancing product is the class of growth promoting steroid hormones.  The use of growth-promoting implants in the US is widespread – an estimated 95% of fed cattle receive growth-promoting implants.  Although implants dramatically increase average daily gain (~10%) and improve feed efficiency (~15%), there is evidence that implants decrease quality grades (Prime, Choice, Select and Standard) and tenderness of the meat. This reduction in quality grade is caused by a decrease in marbling (fat cells--adipocytes--that contribute to the eating quality of meat).  Traditionally, it was thought that implants decreased the body’s capacity to deposit adipocytes within muscles.  However, recent evidence suggests that the use of implants changes the growth curve of the animal such that the weight of the animal at a given physiological endpoint has been increased.  In other words, if implanted cattle are carried to a heavier weight, they will not demonstrate suppression in quality grade.  The two previous studies concluding the implant effects on physiological endpoint, were conducted in cattle of traditional beef genetics. While the vast majority of cattle fed in the US are of traditional beef cattle background, there is a large number of steers that enter feedlots as byproducts of the dairy industry.  Indeed, California places approximately 750,000 Holstein steers in feedlots annually.  These cattle offer much greater genetic consistency than cattle of traditional beef breeds.  Therefore, treatment effects will be more evident.  The objective of the proposed research is (a) to determine the changes in body composition of Holstein steers over time with and with-out implants, (b) determine the effect of implants on the growth curve of Holstein steers, (c) determine the effect of implants on tenderness and quality grade, and (d) calculate the cost of production to achieve a given physiological endpoint.

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06-3-009      Green, David

Evaluation of pesticide efficacy as influenced by adjuvant and nozzle type

Pest control is a significant issue for turfgrass managers, requiring a well developed program to safely and effectively control the various pests which infest turfgrass. Pesticides are one of several methods used in these pest control programs.  Unfortunately past misuse of pesticides has led to severe damage to humankind and the environment.  To protect humankind and the environment government agencies such as the Environmental Protection Agency and the California Department of Pesticide Regulation have developed strict regulations restricting the use of existing pesticides and development of new pesticides.  This regulation has led to fewer and less potent pesticides available for pest control, especially in low volume markets like turfgrass.  Adjuvants have been marketed as pesticide additives to improve efficacy and reduce drift potential.  Studies have shown that these adjuvants can significantly improve pesticide efficacy and reduce drift, but they also may have negative effects such as pesticide incompatibility and increased phytotoxicity (Curran, 1999; Hager et al, 2000).  Additionally, adjuvants have been shown to influence spray nozzle performance.   Adjuvant density and influence on water surface tension impact the atomization and pattern produced by different spray nozzles (Sprayer Systems Co, 2004).  Ferrell et al (2003) showed that adjuvants influenced the performance of different spray nozzles, impacting the tendency of the pesticide to cause phytotoxicity in cotton.  This study demonstrates the need for more research into understanding how pesticide/adjuvant mixtures influence nozzle performance.  No research of this type has been conducted in turfgrass, although there is significant interest in this field by the California turfgrass industry.  Funding for this research will be used to evaluate pesticide efficacy in turfgrass, specifically examining the effect of adjuvants on pesticide and nozzle performance as they influence pesticide efficacy, drift potential, and phytotoxicity.  Objectives of this research will emphasize the control of white clover (Trifolium repens) and English daisy (Bellis perennis) in perennial ryegrass (Lolium perenne) turf as influenced by adjuvant/post-emergent herbicide mixtures applied through different nozzle types.  Results from this research will increase knowledge of pest control techniques in turfgrass, developing improved application techniques which increase pesticide efficacy and minimize environmental contamination from drift.

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06-3-010      Hall, Mike

Assessing high-intensity short-duration grazing as a wildlife management tool in coastal California

Livestock grazing and wildlife management are sometimes in conflict.  For example, in northwestern California, large flocks of migratory geese graze intensively on short grass pastures and put a tremendous economic burden on local dairymen.  In central coastal California, where rangelands are much drier, overgrazing has been implicated as a cause for the decline of numerous wildlife species.  To meet the needs of society, farmers, and the environment, agriculturists and natural resource managers in coastal counties of California must work creatively to integrate livestock grazing with wildlife management.  In this project, we aim to assess the capacity for an innovative rotational grazing practice to meet ranchers’ needs while maintaining biodiversity and wildlife resources in two coastal regions of California.  Working closely with a team of graduate and undergraduate students from both Cal Poly and Humboldt State Universities, we will monitor grass conditions and wildlife responses to controlled grazing experiments.  We propose a series of experiments in Humboldt County to assess the capacity for grazing to create grass conditions on public land that will attract geese away from private pastures and ease the economic burden on the dairy industry.  In San Luis Obispo County, we propose studies to assess the potential benefits of rotational grazing on range condition while assessing impacts on wildlife, especially birds and small mammals.  The work is collaborative and interdisciplinary.  The project will be led by experts on rotation grazing (Mike Hall), wildlife-habitat-relationships (Matt Johnson), and goose management (Jeff Black) in cooperation with numerous industry partners, such as the Humboldt County Farm Bureau, the U.S. Fish and Wildlife Service, and the California Department of Fish and Game.  Thus, students involved in the project will not only learn state-of-the-art approaches for assessing effects of grazing on range condition and wildlife, they will also learn the value of agriculture and natural resource managers working together to identify mutually beneficial land use practices, and that lesson may be the most lasting of all.

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06-3-012      Hawk, Susan

Fatty Acid Modulation of Vitamin A and Breast Cancer

Fatty acids, particularly the omega-3 fatty acids present in fish oils, have been shown to optimize health by decreasing the risk of breast and other cancers.  In animal models, omega-3 fatty acids can decrease the incidence, growth and metastasis of mammary tumors, and in vitro, these fatty acids have been shown to exert growth regulatory effects against breast cancer cells; effects that are very similar to that observed with retinoids. At the cellular level, studies by ourselves and others have provided evidence that alterations in retinoid metabolism may be linked to aberrant signaling and cellular responsiveness in breast cancer cells.  In spite of this link to metabolism, little is known with respect to how normal mammary epithelial cells take-up and metabolize retinoids. Interestingly, my preliminary studies show that select fatty acids are associated with alterations in retinol uptake and retinoid metabolism in both normal and carcinoma mammary cells.  Evidence indicates that some fatty acids may enhance cellular retinoid metabolism and function.  However, the mechanism(s) underlying the anticancer effects of fatty acids is unknown. At present, there is a paucity of data concerning the effects of specific cancer preventative fatty acids (omega-3’s) on retinoid metabolism.  Furthermore, the effects of these and other fatty acids on retinoid metabolism in mammary carcinoma cells is completely unknown.  

I hypothesize that omega-3 fatty acids augment retinoid uptake and metabolism, and that these specific fatty acids exert these effects to a greater extent than other fatty acids.  This enhanced metabolism may in turn serve to optimize or maintain levels of active retinoids thereby potentiating the differentiative and growth regulatory properties of endogenous retinoids and slowing cancer progression.

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06-3-015      Jaster, Ed

Enhanced Growth in Jersey Dairy Calves

Nutrition and health of the young calf is crucial to maximize calf survival and growth rates. Traditionally, newborn calves after receiving colostrum were fed only limited amounts of milk replacer (MR) in an effort to get them to consume dry feed, and potentially reduce the cost of feeding milk replacer.  However, like most mammals, during the first 2 to 3 weeks of life, the calf’s digestive system is immature and is only designed to digest milk-based nutrients efficiently and for these infants, milk or milk replacer must be the major source of nutrition.  Several recent studies have indicated that calves fed on accelerated growth diets enriched in at least one of the three major components: protein, fat, and carbohydrates, had higher growth rates with increases in frame and lean tissue without fattening than controls.  The potential advantage to such changes in feed regimen are reduction in age at first calving, increase in feed efficiency by lowering the cost per pound of weight gain, and improved overall health of the animal and reduced veterinary costs.  However, these studies were done on beef cattle.

This study will be conducted with newborn to 10 week-old Jersey dairy calves at the Cal Poly University Dairy Farm.  Newborn calves will receive colostrum until day 3 of the study at which time they will be divided into three study groups; group 1 will receive the standard industry amount of milk replacer and groups 2 and 3 will receive two different levels of “accelerated or enhanced” replacer.  The calves will be fed the same regimen through week 6, half the amount on week 7 and then weaned.  Calves will be weighed each week and blood tests done every other week. 

Results from this study should allow dairy herdsman to optimize the feeding of their newborn calves to fit the intended purpose of the individual animal – health and early maturity for the females and possibly frame and mass for the males.  California’s dairy industry is one of the largest and healthiest in the world and this project will help it stay there.

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06-3-017      Khalil, Hany

Mechanisms of Protection and Intestine Colonization of Probiotic Bacteria Offered by Milk Fat Globule Membrane in Yogurt as Determined by Laser Tweezers

Food acceptance, and consequently consumer’s choices, strongly correlates with its perceived role in human health. Consumption of probiotic lactic acid bacteria has a very positive impact on human health. Probiotic bacteria can be incorporated in many food products to enhance their health benefits. However, in order to express their benefits, probiotic bacteria must first survive food processing and second colonize the intestine. The influence of processing conditions on their survival and the mechanism of their intestinal colonization are not well elucidated, and published data lack accurate and practical physical evidence. Hence, the objective of this project is to fully understand the survival of probiotic bacteria in a fermented food system, and the impact that the food and processing have on its binding properties. This data is essential in order to develop an ingredient with active probiotic cultures.

Yoghurt offers a readily compatible food system which can function as probiotic carrier. Moreover freeze drying is a process known to minimally impact bacterial viability. Lyophilization (freeze drying) is the removal of water from frozen material. It is an excellent method for preserving microbes and heat-sensitive materials. In commercial practices bacteria are suspended in a suitable protective medium, frozen and exposed to a vacuum. The bacteria maintain their viability in a dehydrated state for a long time if packaged properly. However, the bacteria have to be suspended in a protective medium, De Valdez, G.F et. al.1983. Most common protective medium are skim milk, honey, raffinose, glutamate and lactose. Some hydrocolloids have shown to exhibit some protective effect during freeze drying, Champagne, C.P. et.al. 1996. In this project yoghurt with special formulations will be used as protective medium.

Therefore the experimental approach is to study yoghurt formulations and freeze drying parameters on the survival of probiotic bacteria and the effect that this has on the bacteria’s ability to bind to intestinal tissue. The freeze-dried yoghurt ingredient can then be incorporated in many cereal, fruit, vegetables, meat and dairy food products

The advent of new technologies based on laser traps and ‘tweezers’ allow for accurate measurement of the interactions among molecules and particles. Laser tweezers technology uses laser light and electronic controls to measure forces between microscopic particles. It has been applied successfully to some model as well as biological systems. Laser tweezers technology will be utilized to characterize membrane physical binding between the bacteria, food components, and intestinal tissue. Surface binding is responsible for the protective effect of milk fat globule membrane (MFGM) on probiotic culture during processing as well as their attachment to the intestine.

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06-3-020      Peterson, Dan

Examination of endogenous and exogenous phytase in domesticated birds

Phosphorus (P) is one of the major environmental pollutants excreted by poultry and swine, and excess environmental P is directly related to eutrophication and loss of biodiversity in water systems.  High levels of excreted P from animal production systems are related to the low digestibility of P from plant sources, since it is bound in the phytate molecule which vertebrates cannot break down.  While plant-based ingredients that are fed to commercial poultry and swine actually contain adequate levels of P to meet the animals’ nutrient requirements, this P is not available to the animal.  As a result, inorganic P is supplemented in poultry and swine diets, resulting in P excretion from unabsorbed inorganic sources as well as undigested phytate-bound P.

Phytase is a microbial-derived enzyme that breaks down the phytate molecule, liberating phytate-bound P and rendering it digestible.  To minimize high P excretion levels, exogenous phytase enzyme is often added to diets.  Additionally, transgenic technologies have been used to generate pigs which produce phytase enzyme in the digestive tract. These strategies increase P availability, reduce the need for supplemental dietary P, and subsequently reduce P excretion.  The PI and Co-PI have made substantial progress in generating transgenic quail at Cal Poly which secrete phytase in the digestive tract.

In addition to the need for reduced P in excreta to prevent environmental effects, recent data gathered by the Co-PI indicate that the phytate molecule alters intestinal physiology, such that inflammation is significantly increased in animals fed high dietary phytate levels.  Addition of exogenous phytase enzyme into diets of animals fed high phytate significantly reduced markers of inflammation, indicating that increasing the hydrolysis of the phytate molecule may improve animal performance and well-being, which ultimately will lead to reduced costs of production.

The purpose of the proposed research is to extend current efforts to produce and characterize phytase-transgenic Japanese quail, and to further examine the role of exogenous phytase on intestinal physiology.  These efforts will facilitate the appropriate application of phytase, exogenous or endogenous, to ensure environmental friendliness and maintain animal performance, health and well-being.

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06-3-022      Pettey, Allen

Development of nutrient excretion models in pigs and poultry

Environmental impacts of animal production systems have long been a concern throughout the world.  The issue of excess nitrogen and phosphorus, two primary nutrients implicated in environmental contamination, will become a driving influence in the development of regulations concerning the feed ingredients used in animal rations, limits on sizes of operations, locations of animal production facilities, and measures used to apply animal waste effluent back onto agricultural land.  Due to the concentrated nature in which pigs and poultry are raised in the United States, these two species have become a primary target for regulation of nutrient output.  

One method to estimate the amount of phosphorus being excreted by pigs and poultry is to quantify the true requirement for this nutrient.  This is done by estimating the maintenance needs of the animal, the animal’s influence on digestibility of phosphorus from feed ingredients, and the retention of phosphorus into body tissues.  In the current NRC for swine (1998), this type of modeling approach is used for amino acids, yet a scarcity of data exists allowing for the same methodology to be applied to mineral requirements.  Recent work (Pettey et al., 2004) indicates that a modeling approach is applicable to swine mineral requirements, however, multiple factors influencing these requirements have yet to be studied.  Very little data exist concerning the whole body retention of phosphorus in broilers, thus prohibiting the development of any model approach to estimate requirements and excretion levels at this time.

The proposed studies look to further investigate the factors influencing maintenance requirements for phosphorus in growing pigs and poultry, and the retention rates of phosphorus in whole body tissues.  Four experiments will be conducted using growing-finishing pigs placed in metabolism crates to estimate the effect of body weight, feed intake, phosphorus intake levels, and phytase inclusion on endogenous phosphorus excretion.  A similar study will be conducted in broilers to provide novel information regarding endogenous phosphorus losses in birds.  Coinciding with the estimation of maintenance phosphorus requirements, the retention of phosphorus on a mass basis, and in proportion to nitrogen retention, will be studied in pigs and poultry.  Nitrogen balance has been extensively studied in pigs and poultry, thus correlating phosphorus balance to nitrogen balance in a factorial fashion will allow for greater strength in utilizing derived models from this data into practical industry applications.

The basis of any model used to predict nutrient excretion is an understanding of the true requirement of nitrogen and phosphorus throughout the growing life of the pig and broiler.  The first step in the development of a nutrient excretion model will be to quantify all routes of nutrient utilization in pigs and poultry, and utilize the data collected to develop a set of prediction equations which will estimate nutrient excretion when dietary levels are in excess.

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07-3-003      Garner, Lauren

The Effects of Plant Growth Regulator Spray Regimes and Girdling on Fruit Retention and Yield of Lychee (Litchi chinensis) Trees

The lychee is a subtropical fruit tree crop whose popularity is quickly growing among American consumers, and thus, has the possibility to become a lucrative niche market for California fruit growers.  Production within the United States is currently limited to Florida, where weather conditions have resulted in a highly volatile market price.  To determine if California’s coastal microclimates are appropriate for the growth of this highly lucrative crop, lychee field trials were established in 1999 in numerous commercial orchards.  The trees are beginning to bear fruit but fruit retention and yields are low due to high rates of early fruit abscission that often characterize this crop.  Horticultural techniques such as plant growth regulator (PGR) sprays and girdling often increase fruit retention and yield of fruit tree crops.  Therefore, the objective of this study is to identify PGR and girdling techniques that increase lychee fruit retention and yield.  Techniques to be tested during the 2007 and 2008 growing seasons will be determined prior to the funding period.  A one-year preliminary branch study is currently being conducted.  During the 2006 growing season, individual branches will be treated with one of five synthetic hormone derivatives (IBA, NAA, 2,4-D, 2,4,5-TP or 3,5,6-TP), at one of three concentration rates (5, 50, or 500 ppm), using one, two or three application times (during bloom, during early fruit set and during late fruit set), for a total of 40 PGR treatments.  Girdling will be applied at one of the three above mentioned application time, for a total of 44 treatments, including an untreated control.  The two-year study will then be conducted on a different set of trees in a commercial ‘Brewster’ lychee orchard in Goleta, California using the most promising treatments, as determined during the branch study.  A randomized complete block design (RCBD) with whole-tree experimental units will be utilized (5 trees per treatment with 5 replications per treatment).  The identification of a successful technique or techniques for reducing the abscission of young, developing fruit will add to the growing body of horticultural techniques that California growers can use to produce this unique, profitable fruit tree crop.

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07-3-004      Leon, Ramon

Development of sustainable approaches for weed management in vineyards

Weeds are a serious problem in vineyard production because without the appropriate management they can reduce and even completely eliminate grape yield.  Despite their importance, research efforts have been focused on insect pest and disease management, and weed management research has been limited.  Due to the lack of improvements and innovations on weed management strategies, vineyard growers follow weed control programs that rely on herbicide use and that are not based on clear criteria that justify the need for weed control actions.  For this reason, growers could be reducing their profits by spending in unneeded weed control practices.  In addition, new problems such as the occurrence of herbicide resistant weeds and the demands from the public to reduce the use of pesticides such as simazine that have a negative impact on the environment have increased the need to find alternative weed management strategies that are cost effective and more sustainable.  The present project has two clear objectives: 1) Assess the effectiveness and profitability of alternative weed control tactics (new herbicides, mechanical control, cover crops) to eliminate the use of simazine in vineyards. 2) Evaluate the effectiveness and profitability of using “steaming” as an alternative to post-emergence herbicides.  Each objective will be met by conducting production scale field experiments in a vineyard located in Paso Robles, CA.  The experiments will be conducted in 2006 and 2007.  The results will be used to generate specific recommendations for growers. Information about weed-vine competition and weed species susceptibility to weed control tools will be used to develop criteria for determining the need for weed control.  This information will be complemented with a wide set of weed control tools such as cover crops, steaming and herbicides for which the cost and effectiveness will be clearly characterized.  Thus, growers will have more information and weed control options to optimize their weed management and maximize their profits.  During the experiments and at the end of the project, Cal Poly students and professors, representatives of agricultural industry, and wine grape growers will interact in order to maximize the dissemination of the information generated and to improve weed management in California vineyards.

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07-3-006      Burt, Charles

Canal Seepage Reduction Through In-Situ Soil Compaction

Water conservation in agricultural irrigation projects has become an important subject in recent years, due to the strong competition for a limited resource (water), environmental issues, and the high cost of energy required to move water.   

Canal seepage reduction is a particularly challenging conservation aspect.  Canal seepage varies widely in California, and probably represents somewhere between 4-40% of the conveyed water in unlined canals.  Most irrigation district canals are unlined.  Recent efforts into solving this problem have included efforts to inject Polyacrylamides (PAM) into irrigation district canals, which proved to be less effective than anticipated.  The most typical solution—lining canals—costs about $2.50/sq. ft (about $100/ft for a small-medium sized canal). 

Soil compaction is a standard practice in the engineering of foundations and dams.  It is widely known that optimum soil compaction under controlled conditions can reduce hydraulic conductivity by several orders of magnitude.  Therefore, it seems logical that proper soil compaction might reduce canal seepage.  However, cited work has been conducted primarily with foundation engineering in mind.  A detailed literature search, and familiarity with the industry, has produced no research that deals with the less-than-optimum conditions encountered in the field with irrigation district canals, and identification of the important variables that will influence the success of seepage reduction. 

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07-3-008      Headrick, David

Field Management Plan and Biocontrol Rearing System for Citrus Peelminer

Peelminer, Marmara gulosa Guillen & Davis (Lepidoptera: Gracillariidae), is a recent (1999) and persistent pest of citrus fruit in the San Joaquin Valley.  Peelminer larval stages create serpentine mines, scarring the rinds of citrus fruit and rendering it unacceptable for fresh market sale.  After three years of intensive study, jointly funded by the Citrus Research Board and the Agriculture Research Initiative, we are bringing current research information together to build a management program for peelminer in the San Joaquin Valley that provides growers the necessary tools and information to effectively deal with this pest.  Citrus peelminer pest management requires an ecological approach using techniques such as pheromone traps, a degree-day model, and augmentative releases of natural enemies for successful control. The information gained from this research proposal will also directly benefit management of the citrus leafminer, Phyllocnistus citrella, an up and coming pest in California, as it shares many of the same natural enemies with peelminer. 

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07-3-009      Jimenez-Flores, Rafael

Characterization of functional properties and lipid profiles of cheese treated by supercritical CO2

A major opportunity to increase value and nutritional quality in cheese, which is one of the most important agricultural products in California, is to develop flavorful ingredients with reduced fat.  There has been an historical effort to produce cheese low in fat.  While the market for low-fat cheese is growing, many consumers find the taste of low fat cheese unappealing (Dairy Management Inc. market research).  This may be due to the fact that the majority of the efforts start with low fat milk, resulting in imbalances in the biochemical processes that yield high quality flavor and texture.  A novel approach recently reported from scientists at Cornell University, start with a mature flavorful cheese, and then reduce its fat composition by shredding, melting and eliminating fat by centrifugation.  A subsequent re-assembly produced cheese of acceptable quality (Nelson and Barbano 2004).  The present proposal also uses also mature normal cheeses, and by a novel procedure developed in Cal Poly, using supercritical fluid extraction (SFE) we propose to remove the triglycerides and study the properties of the ingredients produced with the aim to use them in the processed food industry.  Preliminary work with Cheddar and Parmesan cheeses in our laboratory has proven that this approach leaves many of the flavorful compounds in the cheese matrix, including valuable and functional phospholipids.  Using this process a triglyceride rich fraction result containing some flavor compounds whose concentration depend on the kind of cheese.  However, no data is available on the functional properties of the ingredients produced with this procedure.  We propose to study in detail this procedure to reduce fat in cheese, and characterize the valuable ingredients based in cheese for the processing food industry.

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07-3-011      Peterson, Dan

Proteomics Approach to the Analysis of Animal Tissue and Milk Fat Globule Membrane Proteins

Food quality is not only a function of nutritional values but also of the presence of bioactive compounds, which can exert additional effects on human health.

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07-3-012      Peterson, Dan

Tissue-specific regulation of lipogenesis by the transcription factors SREBP and ChREBP

Obesity, type II diabetes, and related metabolic disorders are an increasing problem in the human population, and even in many non-human animals.  Central to these disorders is improper regulation of glucose and fatty acid metabolism both in the liver and in adipose tissues.  Lipogenic enzymes, such as acetyl CoA carboxylase (ACC) and fatty acid synthase (FAS), catalyze the conversion of glucose to fatty acids mainly in adipose and hepatic tissue.  Synthesis of fatty acids within cells is regulated in response to both nutritional and hormonal signals within an organism.  Ingestion of high carbohydrate diets leads to an increase in insulin levels, resulting in the activation of insulin-dependant sterol regulatory element binding protein (SREBP) transcription factors which, in turn, activate the genes for ACC, FAS, and other related enzymes.  Recently, it was shown that dietary carbohydrates also act independently of insulin through another transcription factor termed the carbohydrate response element binding protein (ChREBP), which has been shown to stimulate lipogenesis in hepatic tissue.  The relative contributions of these two transcription factors in lipid metabolism has yet to be determined, although recent studies suggest differential regulation of lipid synthesis in liver and adipose tissue.  Understanding the relative contributions of ChREBP and SREBP will increase our understanding of normal metabolism in both human and non-human animals, and could aid in the development of future therapies for disorders such as type II diabetes and non-congenital lipodystrophy, as well as help to identify targets for development of metabolic modifiers for food animal production.

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07-3-014      Wong, Jeff

Identification of EST's related to mite infestation in Wine Grapes

Spider mites (family Tetranychidae) are among the most widespread and troublesome grape arthropod pests in California.  Sulfur dust, used as a control for grape powdery mildew (Uncinula necator), has been observed and tested for over 50 years, and found to be strongly associated with Pacific mite outbreaks in the central San Joaquin Valley.  The effect has not yet been reported for Willamette mite.  Recent evidence suggests that this phenomenon is not a result of the negative effects of sulfur on natural enemies, but instead is a direct effect on the vine’s ability to mount a defense to mite attack.  Our hypothesis is that sulfur somehow interferes with genetic transcription factors that lead to increased production of phytochemicals antagonistic to mites.  Our objectives include the sequencing of the grape genome to find a gene which responds to applications of sulfur dust and field test the effect.