02-3-004
Beckett, Jonathon L.
Effects of Long-Acting Estrogen-base Growth Promotant on Growth and
Performance and Carcass Characteristics in Holstein Steers.
The use of growth-promoting implants in the
US is widespread, although optimization of compound type and onset of
implant exposure has not been completely resolved.
In particular, 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 preponderance of research has been conducted on traditional beef
cattle genetics. 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. Due to
the profound differences in growth characteristics between dairy breeds
and cattle of more traditional beef genetics, the Holstein steers are
fed for a longer period of time and thus are subjected to repeated
implant regimens.
The implementation of repeated, serial implants can result in
losses in efficiency and growth as the animals are processed more
frequently, and are subject to more injury due to the more frequent
handling. As more
investigators report on the interaction between genetic influences and
implant effects, there is growing concern that traditional implant
regimens are not adequately tested in Holstein steers, particularly as
they relate to season of placement.
The objective of the proposed research is to test the efficacy of a
long-lasting, sustained release estrogen implant, singularly, and in
combination with other growth promotants.
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) effect of
season on implant regimen.
The working hypotheses of the proposed research are (1) A long-acting
estrogen implant can be used in a growth promoting strategy (which
limits the number of times the cattle must be handled), maintains the
rapid growth and high efficiency of other implant regimens, yet
minimizes the detrimental effects of implants on carcass quality.
(2) Different strategies are appropriate depending on the season of
placement into the feedyard.
back to top
02-3-017 Brown, J. Wyatt
Bulk Modified Atmosphere Packaging of Fresh Produce Commodities
The use of Modified Atmosphere Packaging
(MAP) technology is advancing from infancy to its adolescent stages.
As the technology matures, new applications that make the
technology adaptable and user-friendly will require validation.
One such novel application for MAP is the SLX container system
produced by SLX International, a San Luis Obispo-based corporation.
The container is made of food-grade plastic with a hermetic seal
able to contain a modified inner atmosphere.
The container is re-usable and is considered a “green technology”,
as opposed to paperboard containers that are single use and disposable.
It is the intent of the investigators to use the SLX container for the
optimization of shelf-life and shipping quality of California-grown
perishable agricultural commodities.
Primarily, fruits and vegetables applicable to MAP transport will be
studies.
Research parameters include, but are not limited to, respiration
rate of the commodity, color, taste, odor, and microbial load of the
commodity, as well as extension of quality factors over time and
distance shipped.
Optimization of these parameters for various produce commodities will
allow for extended market access of such shipped items.
As regional markets are saturated, growers, packers, and shipper
must seek distant markets.
In addition, with the advent and expansion of the global marketplace,
more and more people desire fresh, high-quality produce items, from
California too, if they can get them.
The main objective of the proposed study is to investigate and define
the criteria and parameters necessary for optimization of quality, thus
allowing for extended shipment of California agricultural commodities.
This will allow for sale of fresh items all around the globe,
especially to lucrative, previously inaccessible markets in Asia and
Europe.
back to top
02-3-060 Burt, Charles
Drip Irrigation Salinity
Drip irrigation is commonly mentioned as the
best means for improving efficiencies and helping to solve California's
water problems.
Specifically, the CALFED program has targeted the funding of new
drip/micro systems as the single best option for generating true water
conservation in California.
The CALFED program has particularly noted that SDI (subsurface drip
irrigation) may yield significant decreases in non-beneficial
evaporation losses. Various
programs by electric utilities and others will also provide future
funding to stimulate an increase in the drip irrigated acreage in
California.
However, there have been serious failures of
drip systems due to salt accumulation around drip emitters - indicating
serious potential problems in arid areas (such as the San Joaquin
Valley) with the sustainability of some types of drip irrigation
(particularly SDI).
There is almost no systematic diagnostic research of the problem in San
Joaquin Valley conditions.
To this point in time, it has been largely assumed that there are no
problems unless one irrigates with brackish water or is in a high water
table area.
But there is no data to support such an assumption.
This research will examine "typical" drip systems, and some
potentially hazardous ones (in Panoche Water District), to determine if
there are indeed damaging accumulations of salt.
If there are, the study will identify any the special leaching
requirements needed for salt removal around drip emitters, as well as
identify the important management practices needed to create a
sustainable irrigated environment with drip.
back to top
02-3-009
Costello, Michael
Cultural Practices for Integrating Arthropod Pest Management with
Improvements in Grape and Wine Quality.
Key issues for grape growers in California
include environmentally sound pest management, sustainable soil
management, irrigation efficiency, optimal vine fertility and improving
wine quality. There is a
great deal of interest in using irrigation management (regulated deficit
irrigation) to improve color, maturity and flavor components of wine.
In addition, cultural practices such as cover cropping and
irrigation management can have a significant effect on leafhopper
numbers by influencing vine vigor.
Recent work suggests that water stress at critical times during the
season can increase leafhopper mortality.
Spider mites are among the most widespread and troublesome grape
arthropod pests in California, and these pests will be at the forefront
of grape IPM in the next few years because of the probable loss of the
most commonly used miticde, propargite (Omite), due to FQPA
restrictions. There is a strong
relationship between vine stress and outbreaks of spider mites which has
been long recognized, and water stress seems to be the most common type
of stress leading to spider mite outbreaks.
There is also a fair amount of evidence correlating sulfur use with
increased spider mite density.
To date, these cultural, pest management and grape quality issues have
largely been studied separately by scientists within a particular
discipline. Our project
integrates these issues into a whole systems vineyard management
program, so that a set of production practices can be used to achieve
multiple objectives. Our
studies focus on two objectives: 1) Irrigation strategies for managing
leafhoppers and improving wine quality and 2) Soil and sulfur management
for spider mites.
We have found that deficit irrigation can be timed to increase
leafhopper mortality and improve wine quality, and we propose the
continuation of these studies.
We also propose studies to measure the potential types of stress
involved in making vines susceptible to spider mite outbreaks, and will
focus our efforts on soil factors and the use of sulfur.
back to top
02-3-059
Costello, Michael
Identifying Environmental Variables that Influence the Severity of
Pierce’s Disease and the Glassy-winged Sharpshooter.
Pierce’s Disease (PD) of grapevines in caused
by a bacterium (Xylella fastidiosa or Xf), and is transmitted by
leafhoppers commonly known as sharpshooters.
PD is usually fatal in grapes, and in California, has caused
millions of dollars of damage in the past decade.
Sharpshooters are a highly specialized group of leafhoppers.
There are at least three native sharpshooters which will transmit
PD to grapes, but during the 1990s, an exotic species, the glassy-winged
sharpshooter (GWSS) has become established in virtually every Southern
California county, and has been trapped in over a dozen central valley
and north coast counties.
The broad host breadth and strong flying ability of the GWSS makes it a
much more serious vector of PD than any of the native sharpshooters.
There are many factors which may be involved in the expression of
PD, including grape variety, climate, adjacent vegetation, proximity to
riparian habitats, soil chemistry, soil physical factors, soil biology
and soil water status. The
general objective of this study is to identify the various factors
involved in the expression of PD.
We propose to investigate and evaluate these factors by collecting data
from several regions throughout the state to analyze how the incidence
and severity of PD in grapevines in influenced by their interaction.
All data collected will be combined into a database that will be
analyzed with canonical correspondence analysis, which will allow us to
assess many dependent variables along with many independent variables
simultaneously. In
addition, we will evaluate the relative effectiveness of four trapping
methods for monitoring sharpshooters, which will enable more effective
surveillance techniques for sharpshooters in and around vineyards.
back to top
02-3-010
Dietterick, Brian
LIDAR Geomorphic Evaluation of Watershed and Channel Characteristics in
the Little Creek Watershed, Swanton Pacific Ranch
Recent developments using LIDAR (LIght
Detection And Ranging) technology has permitted
high-resolution, three-dimensional mapping and the ability to evaluate
landscape features, such as channel and watershed characteristics.
The ability of high-resolution laser altimetry to accurately
identify and evaluate watershed and channel characteristics will be
investigated. Comparisons
will be made between field-mapped inner gorge areas, streamside
landslides, and channel characteristics with the same landscape features
generated with digital terrain models derived from the laser altimetry.
The results of this study are expected to determine whether LIDAR
technology can provide an accurate and cost-effective alternative to
delineating watershed and channel characteristics that contribute to
cumulative watershed effects analysis required under California Forest
Practice Rules. A model
will be developed to identify areas susceptible to streamside landslides
to help predict potential sediment sources for the cumulative effects
analysis and to possibly warrant additional WLPZ (watercourse and lake
protection zone) considerations.
back to top
02-3-022
Eisenberg, Barry
Reducing Nitrogen and Pesticide Run-off from Container-grown Nursery
Stock by Optimizing Cultural Practices Using a Predictive Environmental
Interaction Model
Run-off water contamination is a serious
problem for container-grown nursery stock.
The problem is acute when rain follows a dry period. Developing data from irrigation/run-off collection plots with
the ability to deliver “rain” will enable the construction of a
predictive computer model to take a proactive approach in minimizing
run-off issues. This data
must be linked to leaf, soil, and air temperature, soil and leaf
nutrient status, photosyntheticly active irradiation and transpiration
to have a tool industry can use to optimize production while minimizing
chemical run-off. The
project will also fill the need to develop an education/training tool to
be used in courses and for the industry.
back to top
02-3-016
Hampson, Brian
Aqueous Ozone for Pathogen and
Cross-contamination Prevention
The project goal is to increase the safety of
fresh produce commodities by means of utilizing ozone as a germicide for
wash reduction of surface-borne pathogen contaminants. Dissolved ozone in wash water rapidly eliminates
microorganisms entrained in the water, thus preventing
cross-contamination.
Additionally, this application allows for enhanced water recyclability
and the economic employment of other germicides in combination.
Experiments are designed to elucidate the relationship between dose
(concentration of ozone in solution x time of exposure) and logarithmic
reduction of bacterial pathogens, pathogen indicator organisms, and
indigenous microflora. Aqueous ozone will be applied directly to the exterior of the
fruits or vegetables; used to treat produce wash water for prevention of
cross-contamination; and, applied as a spray wash to various
food-processing surfaces inoculated with Escherichia coli,
generic coliforms, and mixed populations of indigenous bacteria and
fungi.
Experiments will also be performed to demonstrate the removal of
the above microorganisms from the wash water as it makes its way to
drainage, or is disposed of at the end of processing.
These results will be transferred to the produce and agricultural
industries, and will assist with the development of good manufacturing
practices for the use of ozone.
The timeliness of this research cannot be ignored.
Ozone is currently under review by FDA for government GRAS
affirmation.
Self-affirmation by an expert panel occurred in 1997, and as a result,
many companies are using, or are willing to use ozone, however,
guidelines, evidence of efficacy, and dissemination of findings through
conferences, symposia, and workshops is sparse.
back to top
02-3-023
Headrick, David
Citrus IPM: Secondary Pest Biology and Demography II
Secondary pests, such as the fork-tailed
katydid, Scudderia furcata Brunner, have in the past been minor
pests of citrus in California.
In the last few years, such species have increasingly become a problem
in commercial citrus production due to restrictions on broad-spectrum
insecticide usage, reducing pesticide pressures normally controlling
such pests. In areas that
are incorporating the use of natural enemies for control of homopterous
pests, such as California red scale, conventional treatments for
katydids and other secondary pests have proven to be upsetting.
Control strategies are changing every year in response to secondary
pests. Without a solid
biological database on secondary pests, sound management decisions
cannot be made – only guess work and that has proven to be an expensive
and less than adequate option.
The ecological studies are the foundation of future pest management
programs in agriculture.
The only way to achieve effective pest control is to understand the
biology, lifecycles, and reproductive potential of these secondary, and
now more important, pest species.
The main objective of this proposal is to provide support for the
continuation of field studies on katydid damage and validation of our
research model s for their eventual incorporation into a management
program.
back to top
02-1-007
Jimenez-Flores, Rafael
Genetic, Nutrition and Processing Factors Affecting the Lipid and
Protein Composition of Buttermilk
The general objective is to evaluate protein and lipid composition of
milk fat globule membrane (MFGM) present primarily in buttermilk, of
cows with well-defined genetics and under different nutritional feeding
strategies. To this purpose, three areas and researchers are
identified.
Dr. Medrano at UC Davis has been studying the importance of several
genes involved in de-novo fatty acid synthesis of membrane lipids in
cows.
He will continue to refine the
genomic analysis, characterizing important candidate genes coding for
genetic variants of milk proteins and enzymes such as
stearoyl-CoA-desaturase, that impart
specific properties to the mammary gland lipids and therefore to the
MFGM in the selection of cows for this work.
Genetics and nutrition determine the composition of
lipids in milk. For this
reason, Dr. DePeters has designed a suitable number of diets containing
different components known to modify the composition of fat in milk of
genetically selected cows.
The milks derived from this work will be used to establish changes in
lipid and protein composition of the MFGM.
We at
DPTC will use advanced analytical techniques, as well as pilot plant
procedures that have full acceptability in the dairy industry to analyze
and process these cream samples, and the resulting buttermilk.
In addition, DPTC is sought as a supplier to the scientific
community of valuable fractions of this commodity. Thus, a good understanding of the relationship between
composition and variables or biological parameters is vital to be able
to become a premier supplier.
back to top
02-3-028
Jimenez-Flores, Rafael
Organic Acid Determination by Capillary Electrophoresis as Quality
Parameter of Buttermilk
This work focuses on defining and
understanding the correlation between metabolically important organic
acids and sensory characteristics of buttermilk.
Biological and processing parameters influence these
characteristics, and they will be studies from the point of view of
organic acid changes in buttermilk and cream.
Using descriptive analysis and capillary electrophoretic
measurements of different organic acids as indicators of biological or
microbial degradation, we will examine the effects of processing and
storage variables on buttermilk samples manufactured at Cal Poly SLO and
those collected from industrial sources.
This information is necessary for improvement of quality control
and to increase value of buttermilk.
The first step of the research will be to
develop a lexicon describing the sensory attributes of buttermilk.
The lexicon will be developed by a panel of 10-15 judges at UCD as
part of the matching project to this one.
We will then develop and assess instrumental measurements of the
organic acids by capillary electrophoresis.
The technique developed in our laboratory has proven to be valuable
in determining microbial contamination, and is sensitive to most organic
acids at concentrations of 2 ppm.
The last step of the research will be to
examine the relations among expert quality ratings (from members of the
dairy industry), consumer hedonic ratings (from consumers of dairy
products) and descriptive ratings by the trained panel on a subset of
commercial and prototype samples.
This will allow us to understand which sensory attributes drive quality
ratings by experts and freshness acceptability among consumers.
The finding of the research will be prepared
for communication in the form of presentation at national food industry
and dairy industry meetings, publication in peer-reviewed journals and
publication of recommendations for buttermilk manufacturers in industry
newsletters and other outreach publications.
These findings will
form part of our DPTC ongoing short courses to the dairy industry.
back to top
02-3-032
Montecalvo, Joseph
Characterization and Food Product Applications of Acidified Tomato
By-Products
In order for the California tomato processing
industry to remain competitive in a global economy, significant
improvement of in-plant efficiencies must be developed.
In-plant efficiencies should be targeted at a reduction in
operational costs, such as that generated from waste stream discharge,
and utilization of process by-product, as technically and regulatorily
feasible. During the
processing of processed tomato products such as sauce, whole peeled and
paste, tomatoes must have their skins removed in a complete and
efficient manner. Lye
peeling using sodium hydroxide has been shown in plant trials to
significantly facilitate the peeling operation in comparison to steam
peeling, a less efficient method.
As a function of lye peeling, tomato skins
are generated, ground and pureed into a sauce, then acidified with food
grade hydrochloric acid to pH 4.2.
The acidified tomato by-product represents all of the skin and small
amounts of residual flesh from the tomato.
This project will compare the efficiency of
using potassium hydroxide as the alkali peel agent and to generate an
acidified tomato by-product low in sodium which will have significant
marketing advantage in creating low sodium tomato sauces for consumers
who must restrict dietary intake of sodium.
Additionally, storage studies will be used to determine how long
the acidified tomato by-product can be stored under both room
temperature and elevated (100-105oF) storage to simulate a
model warehouse condition. As a function of product development objectives, acidified
tomato by-product will be incorporated into tomato and pizza sauces as
well as salsa and as a topping sauce for canned whole peeled tomatoes.
Formulations for all ingredients will be optimized by sensory
evaluation. The
significance of this study would be to develop specific product
applications for the acidified tomato by-product.
Results from this study will aid commercial
tomato processors in establishing quality control data and regulatory
approval by the FDA.
back to top
02-3-035
Noland, Jaymie
Embryo Recovery Rates Using Fresh and Frozen-thawed Quarter Horse Semen
The use of embryo transfer in the Quarter
Horse (QH) industry has gained momentum over the last decade. Factors that effect embryo recovery rates include the day of
embryo recovery, age of donor, number of ovulations, and quality of the
sire’s semen. Until the approval
of the use of frozen semen as of January 1, 2001, fresh and cooled semen
was used exclusively with the breed in embryo transfer programs.
Little information is known regarding the effect of cryopreservation of
semen on the embryo recovery rates within the QH breed.
By approving the use of frozen semen, the American Quarter Horse
Association has provided the opportunity for faster genetic improvement
and corresponding financial rewards for the QH breeders in California, a
substantial portion of the 11.4 billion dollar equine industry in the
state. The influence of a
genetically superior sire can dramatically affect the industry by the
judicious use of cryopreservation of semen.
As the industry weighs the advantages and disadvantages of the use
of frozen semen, the shortage of useful data regarding its effect on
fertility in embryo transfer programs has created a dilemma for
breeders. The objective of this research project is to provide this
data comparing frozen-thawed semen to the standard fresh semen as it
relates to embryo recovery rates.
This information will assist the industry in making sound decisions
regarding the appropriate use of frozen semen in QH embryo transfer
programs.
back to top
02-3-006
Pedersen, Mary and Berner, Louise
Breastfeeding Duration and Other Infant Practices Among Mothers in San
Luis Obispo County
The purpose of this project is to evaluate
current infant feeding practices, particularly breastfeeding duration
rates and reasons for discontinuation of breastfeeding, among new
mothers in San Luis Obispo County in order to support development of
strategies for breastfeeding promotion.
Moreover, the results will provide baseline information on which to
evaluate success of future promotion programs.
Breast milk is widely regarded as the food of choice for the vast
majority of infants, and it is recommended as the exclusive source of
nourishment during the first six months of life.
While breastfeeding initiation rates are high in San Luis Obispo
and California, there is no statewide or local information on
breastfeeding duration for a cross-section of the population.
Data collected nationally and on subgroups of women, however,
reveal that most women discontinue breastfeeding after several weeks or
months – before the full economic and health benefits can be realized.
The US Department of Health Services, in its “Blueprint for Action
on Breastfeeding”, has called on researchers to “conduct research that
identifies the social, cultural, economic, and psychological factors
that influence infant feeding behaviors” and to “monitor trends on the
incidence and duration of exclusive, partial, and minimal breastfeeding,
including minority and ethnic groups.”
The study proposed here would do so.
We plan to conduct a longitudinal survey (primarily by telephone)
on infant feeding practices, with emphasis on breastfeeding duration and
reasons for discontinuation, of a representative sample of new mothers
in SLO County over a one-year period.
Selected mothers will be surveyed initially in the hospital (to
ascertain willingness to participate, initiation of breastfeeding, and
demographic characteristics). Follow-up phone calls will be made at 1 month postpartum, and
again at 3, 6, and 9 months.
Results will provide data on breastfeeding duration among mothers in SLO
County and the primary factors associated with discontinuation or
success of breastfeeding.
In the short term, results will provide important data in support of
nutrition education efforts of the United States Department of
Agriculture (especially the WIC program), County Cooperative Extension,
and local public health groups.
In the longer term, this study can contribute to better health and
financial savings for mothers and their children.
back to top
02-3-041
Piirto, Doug
Silviculture Management Strategies for Pitch Canker Infected Ano Nuevo
Stands of Monterey Pine – pt 2
Pitch Canker (Fusarium subglutinans) has
become a major cause of growth loss, mortality, and associated economic
impacts in California Monterey pine forests.
There remains a strong need for science based forest management
guidelines of the Monterey pine forest in California given the high
public interest and concern over the spread of pitch canker and the
decline of the Monterey pine forest.
An opportunity exists to develop long-term Monterey pine forest
management studies for pitch canker infected native stands at California
Polytechnic State University’s forest property in Santa Cruz county call
Swanton Pacific Ranch.
Funding was provided by the California Department of
Forestry and Fire Protection to: 1) initiate long-term forest management
studies in the native Monterey pine forests at Swanton Pacific; and 2)
develop guidelines for regeneration and management of Monterey pine
forests in California in the presence of pitch canker.
The research work is being done in collaboration with a number of
institutions, organizations, research scientists, and graduate student.
An initial ARI grant was awarded to cover the first
three of six proposed objectives: 1) install a Continuous Forest
Inventory System for the Scotts Creek Study Area; 2) collect seed from
Monterey pine pitch canker resistant trees; 3) plant this resistant seed
in greenhouse nurseries; $0 outplant these resistant seedlings as part
of the group selection experimental design; 5) evaluate the
effectiveness of broadcast seeding; and 6) develop a model to visually
characterize the influence of pitch canker on Monterey pine stands.
This project will address the last three objectives
and will overlap the longer-term of the CDF funding.
back to top
02-3-042
Pillsbury, Norm
Long-Term Growth, Sudden Oak Death Assessment and Economic Viability of
Coast Live Oak in Three California Counties – Third Remeasurement/17
Years
This study, which began in 1984, is the only
long-term sustainability study on oak woodlands in California.
Since little is known about economic sustainability, site
productivity, regeneration, tree growth and the potential effects of
harvesting on oak woodlands, this project continues to supply valuable
information to ranchers, landowners and foresters who wish to maximize
fiber production in existing stands or want to compare the potential for
different management strategies.
In addition, the recent development of the
devastating sudden oak death fungus has caused widespread concern
regarding the survival of native oak woodlands in Central California.
The study has been expanded to provide an assessment of the
occurrence of Sudden Oak Death and will provide baseline data on oak
mortality. It will also
document the rate of the disease spread in the central coast of
California. Sudden Oak
Death has been found in two of the three counties under study.
back to top
02-3-043
Plummer, William
Efficacy of Adding Platelet Activating Factor (PAF) to Extend Semen for
AI to Enhance Conception Rates
Recent collaboration with Dr. John Diehl of
Clemson University studied the levels of PAF in the gravid reproductive
tracts of swine. This new
study is designed to correlate PAF activity (ligand and receptor) in
sperm relative to fertility, circulating androgen levels, semen
characteristics, and pregnancy outcomes (ie. Litter size).
In particular, pregnancy outcomes will be studied in both pigs and
cattle under artificial insemination practices, with and without
additional PAF.
back to top
02-3-054
Vance, Robert
Development of a Low-fat, Cold Bound Restructured Lamp Chop Suitable for
Broiling
Consumers of meat generally look for products
that are lean, palatable and convenient to prepare.
Recent increases in US poultry, pork and beef consumption have been
attributed to the development of new products that are better portioned,
easy to prepare and have a unique taste characteristics. Lamb consumption in the US, on the other hand, has been on
the decline. Reasons for
this include perceived poor palatability, variability in portion size
and difficulty of preparation.
Recognizing these problems, California sheep producers are interested in
the development of lamb products that are low fat, consistent in size
and eating quality, easy to prepare, and can be competitively priced.
Lamb shoulder is a low value commodity that can be used to produce
such products. Lamb
shoulder meat, boned and trimmed of all external and seam fat, will be
combined with seasoning and a commercial cold meat binding material to
produce a restructured chop of uniform composition that can be portion
sized and cooked quickly on a broiler or grill.
Finished product acceptability will be evaluated via consumer
taste-testing. Successful
production could provide American consumers with a lamb alternative to
other similarly produced meat products.
back to top
02-3-056
Walter, Virgina
Continued Studies of the Effect of Retractable Roof Greenhouses on
Solarization
This project will help determine the effect
of seasonal solarization activities on weed population within
retractable roof greenhouse structure growing fresh cut flower crops. Current methods of soil disinfestations in field production
involve the use of methyl bromide, a chemical being phased out for
environmental concerns by 2005.
For fresh flower field producers to remain economically viable,
alternative methods of soil disinfestations must be developed.
Soil borne problems such as weeks, nematodes and diseases can be
controlled with the use of heat.
Generating it using solarization techniques has been demonstrated in
inland climates such as the Central Valley of California, but the
majority of fresh flowers are grown in cooler coastal climates of
California.
Field flower growers are also building retractable roof greenhouses
to aid in year round field production.
If the effect of solarization with such a structure can be
demonstrated successfully on a seasonal basis, this will help growers
remain economically viable in an environmentally friendly and legal way.
back to top
03-1-006
Mark, Walter
Sudden Oak Death Distribution, Detection, Ecological Impact, Control,
and Spread Modeling
In recent years, an alarming disease was found killing oaks in Marin
County and has now spread to 10 surrounding counties. The cause of this
disease was identified only last year to be a fungal pathogen
Phytophthera ramorum.
The disease this pathogen causes is called Sudden Oak Death (SOD).
Since 1995, SOD has been confirmed from southern Mendocino County to Big
Sur, and is particularly severe in Marin, Santa Cruz, and Monterey
Counties.
Dying trees have been observed in urban and rural forests and
woodlands. The main species
of affected overstory plants are coast live oak, California black, and
tanoak. The disease has
also spread to Shreve's oak, California laurel, California buckeye,
bigleaf maple, toyon, huckleberry, honeysuckle, rhododendrons, and
arrowroot.
Concern now exists that the pathogen may spread throughout
California oak forests, be transported to the forests of other western
states and even to the eastern United States.
In fact SOD was discovered in Southern Oregon through aerial survey
work in 2001. With the
discovery of the pathogen on rhododendrons, there exists a much greater
risk of human transport of the disease via ornamental plants.
The actual current geographic range of SOD
Phytophthera
is unknown.
Project
Objectives include:
1)
Statewide Survey of Extent of
SOD-this will result in a comprehensive analysis and reporting of
the extent of SOD in the State.
2)
Predicting SOD Spread using GIS and Remote Sensing:
A GIS model will be developed that will be verified by continued
monitoring of the spread of SOD.
At the end of the project a predictive spread model will be
available.
Landscape effects will also be modeled to show the impact of SOD on
landscapes.
3)
Ecological Consequences of
SOD progression in oak woodlands:
This data will become incorporated into the GIS model and will show
the impact of SOD on oak ecosystems.
4)
Testing of Existing
Phytophthora Control Compounds:
Efficacy testing will determine if a compound has the potential to
be utilized to control SOD.
back to top
03-3-006
Farkye, Nana
Studies on the Ripening of Cheddar Cheese: Identification of Nonstarter
Lactic Acid Bacteria Isolated from Cheese and their Role in Flavor
Development, and the Formation of Calcium Lactate Crystals
In 1999, U.S. natural cheese production had the
largest growth since 1992 – up 6% or 451.9 million pounds over 1998
levels. American-style
cheese varieties represented 45% of the total U.S. cheese production,
and Cheddar cheese accounted for 79% of the American-style cheese
produced.
This suggests the importance of Cheddar cheese to the U.S. cheese
industry, and California is the second leading producer of natural
cheese in the U.S.
Several quality attributes of Cheddar cheese are
taken into consideration in its suitability for marketing. For retail
cuts and slices, which are packaged in clear plastic wrapping, the
appearance of the cheese affects the visual appeal to customers. Some of
the body, textural and uniformity of color characteristics of retail
cuts of Cheddar cheese come into play in the visual appeal to the
customers. Open texture either caused by mechanical or gas-induced
openings, seamy curd defect, localized bleaching of color, and the
prevalence of white crystalline encrustations are some of the defects
that diminish the visual appeal of the cheese. Some consumers often
mistake the crystals to be surface mold growth. Visual defects are often
magnified in aged cheese, which fetch premium price. The occurrence of
white crystalline encrustation is a common defect.
Cheeses with such defects are generally returned and become an economic
loss to the manufacturer.
Although the identity of the white crystalline material and its probable
causative agents has more or less been established, a clear
understanding of the phenomenon of formation of the crystals is unknown.
Therefore, knowledge of how crystals form and why they form in
cheese would help derive control measures necessary to prevent crystal
formation and would lead to insuring quality cheese and increased
profitability to the cheese industry.
back to top
03-3-007
Gill, Samantha
Modeling Height to Crown Base and Ladder Fuels in Giant Sequoia Groves
This proposed research will develop models of the height to live crown
base of conifer trees within the new Giant Sequoia Monument in the
Sierra Nevada. One set of models will be developed using commonly
measured tree and stand density measures (called distance independent
models). Another set of models will be developed using information about
the neighboring trees and vegetation (distance dependent models). We
will investigate whether the inclusion of distance to neighbors is a
significant improvement over the distance independent models. Both types
of models can be incorporated into models of fire spread. Models of fire
spread are very important in the Giant Sequoia groves because they
currently have very high fuel loads due to decades of wildfire
exclusion. Most of the giant sequoia groves in the Giant Sequoia
National Monument are currently at high to extreme risk of catastrophic
loss to wildfire under 90th percentile burning conditions (recent
analysis done by Sequoia NF). Wildfire behavior in forested canopies is
not well understood. These new models will enable fire management
personnel to plan more effective fuel treatment strategies to protect
the groves. Also, distance dependent models of ladder fuels (vertical
structures that allow fires to spread to the tops of trees) will be
developed using the distance dependent data.
In addition to the development of models, inventories of the giant
sequoia groves will take place. Groves will be sampled for live trees,
dead trees, down logs, understory vegetation (hardwoods, shrubs, forbs
and grasses), surface fuels and duff. Sampling will be intense enough to
reasonably assure a standard error of 15 percent for basal area per acre
for live trees. Inventories use the U.S. Forest Service Forest Inventory
and Analysis (FIA) process and have proven to result in a detailed and
accurate documentation of existing forest structure and species
composition. These inventories will be used for comparisons across the
groves as well as for management purposes and future research projects.
back to top
03-3-008
Green, David
Evaluation of Annual Bluegrass Performance Under Different Soil Depths
in a Sand-Based Soil System
Annual bluegrass is a turfgrass species with
broad genetic diversity ranging from light green annual to dark green
perennial biovars. This grass species is one of four commonly used for
golf course greens due to its adaptation to the close mowing and high
wear associated with the game of golf. Annual bluegrass is the preferred
grass species for golf course greens throughout much of California,
where cool moist climates are found on irrigated turfgrass surfaces.
Unfortunately, this grass species has poor tolerance to temperatures
exceeding 30° C. Heat stress experienced during the summer months in
California results in reduced root depth and increased susceptibility to
several disease pathogens. During periods of heat stress, it is not
uncommon for these factors to cause necrosis on large areas of turfgrass
surfaces. Personal observations and industry interviews have identified
poor root depth and infection from fungal pathogens as two of the
primary casual agents for annual bluegrass failure on golf course greens
during heat stress. Previous research into proper management for annual
bluegrass has been limited to fertility regimes and pest control.
Funding of this research will be used to evaluate optimal management
techniques to improve root depth for annual bluegrass during heat
stress. One aspect of the study will examine moisture retention and
annual bluegrass performance under 4 root-zone media depths in
sand-based golf course greens constructed according to specifications
produced by the United States Golf Association. Specifically objectives
of this study will evaluate 3, 8, 10, and 12 inch root-zone profiles in
providing adequate moisture retention and soil media depth for optimal
root growth for this grass species. Secondly, this research will
evaluate integrated management programs for control of fungal pathogens
inhibiting root growth. Numerous chemical fungicides will be screened
alone and in an integrated program to define optimal control of the
fungal pathogens Colletotrichum graminicola and Sclerotinia homoeocarpa.
These screens will be conducted during periods of conducive
environmental conditions favoring each pathogens. Results from this
research will improve knowledge in management of annual bluegrass during
critical periods of heat stress.
back to top
03-3-010
Headrick, David
Ecological Studies and Natural Enemy Evaluations for Citrus Peelminer
The citrus peelminer, Marmara gulosa, is a
lepidopteran rind and stem miner of citrus and other plant species. The
peelminer was introduced into the southern San Joaquin Valley of
California from Coachella Valley approximately three to four years ago.
Subsequent to its introduction it has spread as far north as Fresno
County and populations have exploded on susceptible varieties with as
high as 70% fruit infestations in the Exeter area in 2001. Initial
studies (conducted by UC and CDFA personnel) have shown that natural
enemies endemic to the Central Valley that attack mining-type insects
are largely ineffective at population control. Initial field studies on
growth and development of peelminer on grapefruit indicated three
factors contributing to the economic threat posed by this species: 1.
Individual miners create extensive mines on fruit (average = 20 inches)
and that there are several individuals (~10) per fruit. 2. Out of 100
individuals, 30% survived through the winter as late instar larvae on
the rinds of infested fruit. Another 20% exited the fruit for pupation.
3. There was extensive mining on the stems of certain citrus varieties
and extensive use of alternate host plant species. Research objectives
include continuation of ecological studies of peelminer and releases of
natural enemies for its control.
back to top
03-3-013
Plummer, Bill and Beckett, Deborah
Development of Successful Sex Determination Method of Bovine Embryos
Utilizing Embryo Biopsy and PCR
Producers of domestic livestock strive to improve
genetic influences in their herds. This requires identification, and
propagation of animals that demonstrate desirable characteristics. The
more animals available from which to select, the greater the opportunity
to discover high-performance animals. Predetermination of the sex of
offspring would provide a greater number of males or females from which
to select the top individuals that will contribute the genetics to the
next generation. Many attempts at sexing semen and identification of sex
in preimplantation embryos have been mildly successful. However, 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 variable success in fresh embryos. However, manipulation
of cryopreserved embryos reduces viability of the embryos (Bredbacka,
1998). Therefore, novel approaches to improve pregnancy rates may result
in effective reproductive rates. One such approach is to vary the number
of manipulated, cryopreserved embryos transferred into each recipient to
increase the chances of successful pregnancy. The proposed research will
identify the most successful techniques to biopsy and sex embryos using
the mouse as a model animal. DNA from collected cells will be amplified
using polymerase chain reaction (PCR) or sex specific probes to
determine sex. Secondly, the most effective techniques will be applied
to cattle embryos and survival rates in micromanipulated, cryopreserved
embryos will be determined. Finally, recipients will be implanted with
one or two embryos that sex has been previously determined. Pregnancy
rates, including the incidence of twinning, will be recorded. The
hypothesis is: A single method for sexing bovine cryopreserved embryos
can yield high accuracy and high pregnancy rates for the desired sex.
back to top
03-3-014
Solomon, Ken
Estimation of Distribution Uniformity from Field Evaluations of
Irrigation Systems
Distribution Uniformity (DU) measures how
evenly an irrigation system distributes water to all portions of the
irrigated area. Field evaluations are conducted to assess the DUs of
actual operating irrigation systems, and to provide diagnostic guides
for system or management improvements. In the field evaluation
procedure, measurements are taken to characterize individual factors
(components) which each contribute to the overall system DU. Presently,
an approximate procedure is used to estimate the system DU from the
component DUs, until more correct mathematical procedures have been
developed. It is the goal of this project to establish those
mathematical procedures. Specifically, the objectives of the Estimation
of Distribution Uniformity from Field Evaluations of Irrigation Systems
project are to: (1) Collect field evaluation data on typical irrigation
systems within the San Joaquin Valley. (2) Develop the mathematical
procedures to determine the overall distribution of irrigation amounts
from the measurements on each component. (3) Describe the overall
distribution of irrigation amounts in a mathematical form that will
support further use of the data for uniformity and other studies. (4)
Validate or improve the currently used procedure for estimating system
DUs from field evaluation data on uniformity components. Prior work in
each of these areas has been limited to theoretical computer
simulations, and in many instances has not considered the full range of
components affecting overall uniformity. The opportunity exists to place
theory on a solid footing by basing the uniformity studies on real
irrigation systems and actual field evaluation measurements. The project
will result in improved tools for analyzing irrigation uniformity. The
currently used DU estimation techniques will either be validated, or
improved upon if they are found to be lacking. Farm cooperators,
irrigation districts and government agencies have expressed interest and
financial support for the field evaluations of irrigation systems in
order to improve irrigation systems, verify the performance of new
systems, and the characterize the irrigation systems within a region.
Improved tools for analyzing field evaluation data will strengthen the
evaluation program.
back to top
03-3-015
Steinmaus, Scott
Elucidating the Genetic Mechanism of Glyphosate (Roundup®)
Resistance in a Biotype of Weedy Ryegrass (Iolium spp)
In a project conducted during several labs in
Advanced Weed Science (PPSC 405), we demonstrated that the genetic
mechanism of glyphosate (Roundup) resistance in a weedy ryegrass was not
the result of genetic transfer from Roundup Ready ® crop species. We
propose to take the next step by isolating and sequencing the target
site in susceptible and genetically modified plant species so that we
can better understand how the resistant ryegrass may be so tolerant of
glyphosate. We will acquire the sequence for the "Roundup Ready ® gene"
(i.e.CP4-EPSPS) from the U.S. Patent Office under which Monsanto has
patents for its Roundup Ready® technology. Next, we will compare these
target site sequences with that of the glyphosate resistant ryegrass
biotype. Single amino acid substitutions in the EPSPS enzyme have
conferred glyphosate resistance to two other weed species, and we want
to see if one of these substitutions might be explaining the ryegrass
resistance. Understanding the mechanism for glyphosate resistance is
significant because Roundup Ready® crops on which Roundup® is applied
for weed control comprise a significant portion of farmed acreage in the
US and California. Over 50% of the cotton in California was Roundup
Ready® in 2001 and that number is projected to increase for 2002.
Glyphosate is currently a very effective broad-spectrum herbicide that
controls almost any plant species that isn't Roundup Ready®. It has no
soil activity, breaks down readily in the environment, and is relatively
non-toxic to humans or animals. Preserving its mode of action by slowing
down the development of resistance in the weed populations will increase
the useful life of this relatively nontoxic herbicide. We can better
understand how to preserve the glyphosate mode of action by
understanding how weeds are developing resistance to it. This project is
designed to answer questions regarding the genetic mechanisms of
glyphosate resistance and will accentuate an already successful,
meaningful lab exercise for undergraduate and graduate students. This
project is also designed for students to acquire data for their senior
projects and masters theses.
back to top
03-3-018
Williams, Doug
Data Collection from a Microturbine Operating on a Covered Lagoon
Methane Recovery System
This proposal is to fund the data collection
from the lagoon-type methane recovery system at the Cal Poly dairy,
which has approximately 300 cows, calves and heifers. The project at
present consists of a 14,000 cubic meter (4 million gallons) earthen
lagoon, with pump and piping to transfer the dilute dairy manure
wastewater from the solids separator to the new lagoon. Also included is
a 45-mil thickness, reinforced polypropylene lagoon cover of
approximately 4600 square meters including Styrofoam floats, weights,
tie-down and gas manifold system. This covers approximately 90% of the
total lagoon surface area. The existing biogas handing system includes
piping to condensate trap, gas meter, gas blower and continuous-ignition
flare. A 30 KW Capstone microturbine with associated compressor and heat
exchanger has also been obtained for converting the biogas into
electricity. Previous CSU-ARI and WRBEP grants have paid for purchase
and installation of the equipment, and this proposal is to fund the
operation of this equipment. Matching funding will be received from
FlexEnergy to test a "Flex-Microturbine" which is an improved model of
the Capstone unit. The research plan is to operate the lagoon-microturbine
system for one year in order to obtain a complete set of data including
all the operating parameters - wastewater flows, biogas production,
electrical production, and air emissions. This project will provide the
following environmental and economic benefits: odor control by capturing
the manure gases including ammonia; preventing methane, a significant
greenhouse gas, from escaping into the atmosphere; reducing water
pollution; and providing the economic benefit of electricity worth over
$15,000 annually.
