2008 Annual Report
1a.Objectives (from AD-416)
Changing consumer demands for more nutritious and culturally diverse foods are driving vegetable production into new arenas. Producers who diversify their agricultural operations will be in a position to capitalize on these changes. The overall objective of the project is to develop improved and sustainable systems that vegetable producers can use to maintain a competitive advantage while delivering safe produce of high quality to consumers. Specific objectives are:.
1)Develop integrated, sustainable, including organic, production systems for vegetables;.
2)Identify components of vegetable production systems that influence phytonutrients, and related quality factors, in vegetables;.
3)Identify and prioritize key weed/crop interactions and characterize the optimum control mechanisms for those weeds in vegetable crops;.
4)Develop economical, sustainable, including organic, and ecologically sound integrated production strategies that control weeds in vegetables; and.
5)Determine application timing and rate of manure needed for organic vegetable crop production systems.
1b.Approach (from AD-416)
Components of vegetable production systems, including organic methods, will be studied in the greenhouse and field to determine how they interact with environmental and soil characteristics. To this end components that limit, or enhance, quality of transplants, or quantity of yield, will be identified, long-term sustainable, including organic, production systems will be developed, and effects of the production systems on expression of quality factors will be determined. In support of these efforts, weed/crop problems in horticultural crops (emphasis on onions, peppers, sweet corn, squash, melons, and watermelon) will be identified and prioritized, and effects of cultural practices, including use of allelopathic compounds and other biological control agents on weed species determined. Cultural practices that improve crop yield will be developed so that superior products will be delivered to consumers in a sustainable manner.
Substantial results were realized, and others will be completed during 2008. A production system using organic materials was developed, with transplants being equivalent to those produced with conventional methods and materials. It was determined that addition of bacteria in the potting medium beneficially affected transplant production. Similarly treated seedlings were moved to the field to determine if effects found in the greenhouse carried over to the field. Production during the 3-year transition period from conventional to organic can be affected by inputs. A study of the transition period using multiple crops and inputs determined that production during the transition period is costly, but yields increased over time. The soil was inoculated with beneficial microbes. Peanut was planted in the first year and followed by vegetable crops in three subsequent years. Inoculation with microbes did not provide benefits to plant development and yield. In order to maximize yields multiple crops could be planted in the same year. Early maturing ryegrass was followed by two additional vegetable crops; all crops were harvested with sufficient time left to re-establish the cover crop. Establishment of onions with greenhouse-grown transplants is feasible. It was found that yield increased as plant density increased, but additional fertilizer is not needed. When harvested at different levels of top breakover it was found that harvest could be earlier and nutrients in bulbs maximized. Whether it is necessary to apply manure every year in production of organic vegetables has been examined; results will be obtained in 2008. Weeds in vegetable crops are a major problem regardless of whether the production system is organic or conventional. Corn gluten meal was deemed safe to use when applied to spring-transplanted onions and non-pungent jalapenos, and provided good to excellent early weed control. The synthetic herbicide pendimethalin provided superior weed control and crop yields compared to corn gluten meal. There are potential benefits when corn gluten meal is used for initial preemergence weed control. It was determined that corn gluten meal can be safely band applied for weed control to direct-seeded organically grown vegetables. The phytotoxicity, application rates, and incorporation methods of corn gluten meal for direct-seeded cucurbits and beans were determined. The impact of the research was that production systems were designed to give producers flexibility in determining levels of inputs to use to maximize efficiency. Additional impact was that organic post-emergence weed control strategies were developed for early season weed control; integrated systems need to be developed for season long control. Impact is derived from use of application technology with other powdered or granulated materials in organic production. The overall impact of the accomplishments is that producers have new information on which to make decisions concerning production systems to maximize profits while sustaining yield. (NP 305, Component I, Problem Statement C)
Long growing season conducive to biofuel crop production:
The southern portion of the US has an extended growing season which is conducive to development of production systems that include biofuel crops. Research was conducted by a scientist at the South Central Agricultural Research Laboratory, Lane, OK, to determine if bioethanol crops (sorghum, sweet corn) and biodiesel crops (canola, sunflower) can be established at various planting dates and brought to harvest. All crops were harvested; some were more sensitive to planting date than others. The impact is that producers have been informed of the ability to include biofuel feedstocks into diversified production systems. (NP 305, Component I, Problem Statement C)
Irrigation necessary after prolonged rain events:
There was an unusually high amount of precipitation during the 2007 growing season. Research was conducted by a scientist at the South Central Agricultural Research Laboratory, Lane, OK, to determine if it would be necessary to provide irrigation during the growing period of vegetable crops established after cessation of the rains. Irrigation was needed to improve yields of vegetable crops (cucumber, pepper, sweet corn), indicating that there was not sufficient water stored in the soil to support growth after cessation of rain. The impact is that producers understand that they can not rely on stored water from heavy rainfall to maintain the production of vegetable crops. (NP 305, Component I, Problem Statement C)
Organic weed control for spring-transplant vegetables with Corn Gluten Meal:
Weed control ranks as the number one priority among producers of organic vegetables. Corn gluten meal has potential as an organic preemergence weed control. Research was conducted by a scientist at the South Central Agricultural Research Laboratory, Lane, OK, to determine the impact of corn gluten meal as an organic herbicide on spring-transplanted onions and non-pungent jalapenos. It was determined that corn gluten meal was safe when applied to spring-transplanted onions and non-pungent jalapenos, and provided good to excellent early weed control. This research will directly benefit certified organic producers by providing application rates, weed control efficacy, and safety information for corn gluten applications, and increase use of corn gluten meal for transplanted organic vegetable crops. The research will have impact for researchers, industry, and producers by providing the foundation to investigate and use supplemental post-emergence weed control for organic crops using corn gluten meal as a preemergence herbicide. (NP 304, Component VIII, Problem Statement A, C, and D)
Corn Gluten Meal can be safely applied to direct-seeded organic vegetables for weed control:
Due to corn gluten meal's phototoxicity to germinating and emerging seedlings, it is not recommended for use as a preemergence weed control method for direct-seeded crops, but limited use to established crops, i.e., turf. Research was conducted by a scientist at the South Central Agricultural Research Laboratory, Lane, OK, to develop application technology for safe use of corn gluten mean with direct-seeded vegetables. Equipment was designed, developed, and evaluated in such a manner to apply corn gluten meal to protect direct-seeded vegetables, while continuing to control weeds. This research provides the potential application of corn gluten meal as an organic preemergence herbicide for direct-seeded vegetable crops. The research has provided impact in that the technology is being accepted for application of other powdered or granular materials with potential for use in organic production. (NP 304, Component VIII, Problem Areas A, C, and D)
Amount of top breakover indicates nutrient content in onion bulbs:
As onion plants mature the tops breakover; an acceptable industry standard for harvest is when 50% of the tops have broken over. Research was conducted by a scientist at the South Central Agricultural Research Laboratory, Lane, OK, to determine if the amount of top breakover (10-50%) is related to nutrient content of bulbs. Most nutrients were at maximum levels in bulbs at 20% breakover. The impact is derived from the finding that time of harvest might be adjusted so that bulbs can be harvested earlier to maximize nutrients available to the human diet. (NP 305, Component I, Problem Statement C)
5.Significant Activities that Support Special Target Populations
a) Surplus produce, approximately three tons, from vegetable field plots distributed to local food banks and similar operations through the USDA Gleaners program.
b) Abstracts submitted by students for presentation at the annual meeting of the Society for Advancement of Chicanos and Native Americans program were critiqued and returned to the Program Manager.
c) Day-long outreach to Native Americans (students, teachers, families, farmers, and community), USDA/Oaks Mission School 2007, Native American Career and Information Fair.
d) Presentation and planning sessions with Texas Landowner Association at their annual conference, and information on specialty crops and niche markets was provided to members of the organization.
e) Provided mentoring to a female, Hispanic, graduate student through MentorNet.
|Number of Web Sites Managed||1|
|Number of Non-Peer Reviewed Presentations and Proceedings||6|
|Number of Newspaper Articles and Other Presentations for Non-Science Audiences||1|
Russo, V.M. 2008. Plant density and N fertilizer rate on yield and nutrient content of onion developed from greenhouse grown transplants. HortScience. 43(6):1759-1764.