215 – California Berry Crops: Improving Water Efficiency
Principal Investigator: Dr. Ramiro Lobo, Small Farms and Agricultural Economics Advisor, UC Cooperative Extension. For more project information, click here.
Escalating water prices and prolonged drought conditions throughout various regions of the state have forced specialty crop growers to re-assess their irrigation practices and determine if they can reduce their water use in the production of blueberries, blackberries and strawberries without sacrificing yields and quality. The near and long term effects of decreased water availability will alter the way berry crops are grown; farming practices will need to be modified to use water more efficiently, with concomitant adjustments for salinity and nitrogen management. This project will assess the effects of reduced irrigation on yield, normal growth parameters, postharvest quality and profitability of strawberries, blueberries, and blackberries through replicated trials in the Central Coast region, Sothern San Joaquin Valley and Southern California. We use a randomized complete block design with 4 replications and 5 irrigation treatments, varying from 80% to 120% of ET for strawberries and 25% to 125% of ET for blueberries and blackberries. Postharvest assessment measures include nutritional content, shelf-life, flavor, texture and consumer preferences. We revise existing cost and returns studies to assess the potential impact of reduced irrigation levels on crop profitability. We disseminate our findings through field days / workshops and published reports. Our UC Davis and UC Cooperative Extension team include horticulturalists, irrigation specialists, postharvest physiologists, and agricultural economists with extensive specialty crops experience.
226 - UC Davis Short-Day Strawberry Breeding Program and Research
Principal Investigator: Dr. Steve Knapp, Department of Plant Sciences, University of California - Davis. For more project information, click here.
The UC Davis Short-Day Strawberry breeding program and research has historically been conducted at the South Coast Research and Extension Center, and we would like to resume that collaboration. Our breeding program will encompass the seedling phase from sowing to selection, and advanced selection trials. The research efforts will encompass a genome wide association study focused on fruit quality traits and may include disease resistance research for both Macrophomina phaseolina and Colletotrichum sp. We anticipate that both the research and breeding efforts will result in the release of commercially-relevant short-day varieties that excel in their yield, fruit quality and disease resistance.
31 – Experimental Nematicides
Principal Investigator: Dr. Becky Westerdahl, Department of Nematology, University of California – Davis. For more project information, click here.
Current control methodology for root-knot nematode relies on the use of Metam sodium and Telone II. Metam sodium, for example, was used on 33% of California’s carrot acreage in 1997 and Telone II was used on 10%. The potential for loss of the standard chemical nematicides due to various environmental concerns is great enough to warrant a continued search for alternatives. Each year, a number of “promising” candidates are promoted by various sources. These include chemical nematicides, and what are termed natural or novel products or soil amendments. Even though many of these may not prove to be efficacious, demonstrating this by comparison to a standard nematicide treatment provides valuable justification for maintaining current registrations. Such a process succeeds in sorting out those that do truly have potential for nematode management such as the Valent (formerly Abbott Laboratories) “biological nematicide” DiTera which has recently obtained California registration.
65 – Nematode Control
Principal Investigator: Dr. Philip Roberts, Department of Nematology, University of California – Riverside. For more project information, click here.
The project site is infested with three distinct populations of root-knot nematode, two of Meloidogyne incognita and one M. javanica. We will continue to use the site to identify, characterize and breed host plant resistance to root-knot nematodes into a series of advanced breeding lines and varieties of susceptible field and vegetable crops, especially cowpea (blackeye beans) and carrot, and possibly large and baby Lima beans. The site is used comparatively with other infested sites at field stations in the San Joaquin Valley (KREC) and Coachella Valley (UCR-CVARS). The research is part of a focused effort to develop nematode resistant commercial varieties suitable for California, thus providing alternatives to soil fumigation for nematode management. We are evaluating different breeding populations, genetic stocks, and germplasm lines of blackeye beans and carrots with and without nematode resistance genes, in plots with different nematode population levels. These experiments provide assessment of the relative value of several resistance genes in each crop for protecting against nematode infection and promoting yield. The research is conducted in cooperation with breeding programs from the industry, USDA, and UC, and it is a long-term effort necessitated by cycles of screening, selection, and re-screening and selection as resistant materials are identified and advanced. The project site is an important resource in development of nematode resistant crops and their effective deployment in annual crop systems for California and elsewhere.
104 – Alternatives to Nematicides
Principal Investigator: Dr. J. Ole Becker, Department of Nematology, University of California – Riverside. For more project information, click here.
For more than half a century, methyl bromide (MBr) alone or in combination with chloropicrin has provided growers of high value crops with a very effective tool to control plant pathogens, parasitic nematodes and weeds. The US ban of MBr dictates a major production change that requires the evaluation of alternative methods and pesticides. Furthermore, many organophosphate and carbamate pesticides that include all of the currently California registered non-fumigant nematicides will be severely restricted or even taken off the market as a consequence of the Food Quality Protection Act. This project is designed to evaluate new nematicides and crop production strategies for management of plant-parasitic nematodes.
114 – Biology and Management of Sugar Beet Cyst Nematode
Principal Investigator: Dr. Edward Caswell-Chen, Department of Nematology, University of California – Davis. For more project information, click here.
In 1987, plant-parasitic nematodes were estimated to cause a 12.3% reduction in yields of the world's major crops, and a 10% reduction in sugar beet yields. The cyst nematodes are considered the third most important group of plant-parasitic nematodes in the world. Heterodera schachtii, the sugar beet cyst nematode (SBCN), is the most important nematode pathogen of sugar beets, and it occurs in areas where sugar beet and cole crops are grown. Our research addresses this species. Estimated sugar beet losses attributed to SBCN range from 1 - 70%. SBCN is a serious pathogen of sugar beets and cole crops (broccoli, Brussels sprouts, cabbage, cauliflower, kale, rape, rutabagas, spinach, and turnip).
Nematodes are often managed by nematicides. "Sustainable'' or "alternative'' agricultural systems need to be developed which will integrate naturally occurring beneficial interactions to manage nematodes. Achieving successful integrated management will depend on combinations of tactics including, resistant cultivars, and crop rotations, each providing a limited level of population suppression.
Research objectives cover several different aspects of sugar beet cyst nematode (SBCN) management including experiments to assess: the damage threshold of SBCN on sugar beets and cole crops growing in sandy-loam soil in southern California, the relationship of the damage threshold to planting date and soil temperature, nematode population dynamics relative to planting date and temperatures, and evaluation of chemical and non-chemical methods of control.
174 – Cover Cropping to Manage Pests in Vegetable Production
Principal Investigator: Dr. Antoon Ploeg, Department of Nematology, University of California – Riverside. For more project information, click here.
Suppression of pests and pathogens has often been highlighted as a valuable “byproduct” resulting from a high degree of biodiversity. However, current agriculture practices (e.g. monocropping, increased use of external inputs) have caused a decline in biodiversity. When pest control and other ecosystem services previously contributable to biodiversity are lost, the economic and environmental costs can be significant. Cover crops are non-cash crops that are typically grown during the off-season for their indirect beneficial effects. In agricultural systems, cover crops may aid in the control of insects, pathogens or weeds. Societal demand for environmentally friendly crop production has increased the demand for pest suppressive cover crops. Although cover crops have been shown to reduce plant damage caused by weeds, nematodes, and insects an integrated approach for using cover crops to manage pests is lacking. Vegetables are attacked by insects, disease, and nematodes which significantly reduce yield and quality. Weeds compete with vegetables further reducing yield. Cover crops may directly affect pests, and also enhance beneficial organisms.
The study proposed here would address the lack of an integrated approach to evaluate the effect of cover. The results from this study will provide data that ultimately will lead to lessening the reliance on synthetic pesticides, particularly on soil fumigants. The latter group of pesticides are being targeted for restrictions because they are the main contributors to the emission of volatile organic compounds (VOC) a serious threat to air quality.