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The most significant area for U. S. organic cotton production is in the High Plains of Texas. Availability of planting seed suitable for organic production in this region is a primary concern of organic cotton producers because major seed companies have discontinued non-genetically modified varieties. Major constraints to organic cotton production include early-season insect pressure from thrips complex, as well as drought tolerance and fiber production in cooler environments. Ongoing research at Texas AgriLife Research breeding program includes screening wild cotton collections for thrips tolerance, developing varieties for limited water production and a long history of fiber quality improvement. <P>This project focuses on introgression of thrips tolerance into high quality, sustainable cotton varieties and developing integrated pest management solutions for production of new, conventional varieties. <P>The long term goal of this project is to develop adapted, high quality cotton cultivars resistant/tolerant as seedlings to damage by the Texas High Plains thrips complex. At present, the major cotton industry exclusively uses insecticides for thrips control. Since this type of control is not available to organic cotton growers they are at the mercy of this pest.<P> It is expected that a thrips resistant cultivar will be developed and made available to organic growers through a partnership with All-Tex Seed Inc / Levelland Delinting at the termination of the project, along with best management practice guidelines for growing the new varieties.<P> An ongoing breeding program with lines developed from this project will seek to provide a pipeline of improved non-transgenic cotton cultivars that address the primary constraints of organic cotton production in the major organic cotton growing region in the U. S. Without this potential pipeline, organic cotton producers are at risk of losing available planting seed options.<P> The extension and education components of this project will be developed, disseminated, and evaluated with input from grower clientele and other key stakeholders.<P> The evaluation of the impact of the outreach program will include two major components: 1) measuring delivery of practical information to growers and pest control advisers (short term outcomes) and 2) measuring changes in grower and pest control adviser knowledge, skills, and thrips management practices and linking those changes to specific outreach products (medium-term outcomes). Additionally, economic impacts of changes in thrips management practices as a result of these outreach efforts will be quantified. <P>These assessments will be made at various venues where information delivery has been made (county and regional meetings), and by surveying individual organic cotton growers identified by our advisory panel.
Non-Technical Summary: More than 90% of the cotton grown in Texas currently comes from varieties with biotechnology traits and commercial seed developers are not releasing new conventional varieties. GMO varieties are both unapproved in organic cotton production and prohibitively expensive for many low-input producers on the Texas High Plains, which produce a majority of the cotton grown in the U. S. A. The Texas High Plains represents the most viable production region for organic cotton, with significant insect pressure coming mainly in the first 40 days of growth. Targeting early-season insects through tolerant conventional varieties and their interaction with approved insect control strategies can have potential economic benefit to producers who use organic methods. Organic cotton fiber is an emerging specialty market, both domestically and internationally. In 2008, approximately 50% of cotton planted in the Texas High Plains was treated with a preventative insecticide and 17% of the acres were treated with at least one foliar remedial insecticide. In conventional cotton, the high front-end cost of all effective preventative thrips management tactics is a limiting factor for producers when considering the adoption of preventative thrips management strategies. Organic cotton growers are currently not afforded the luxury and simplicity of utilizing effective at planting, preventive treatments for thrips; no such options exist. Currently, few Texas organic cotton growers utilize any treatments to manage thrips. A combination of greenhouse screening of ancestral cotton accessions, modified pedigree breeding methods, choice and no-choice field resistance screening and factorial experiments with approved substances for organic cotton production targeting pest resistance will be used to develop cotton cultivars suitable for organic cotton production. It is expected that a thrips resistant cultivar will be developed and made available to organic growers through a partnership with a seed company at the termination of the project, along with best management practice guidelines for growing the new varieties. An ongoing breeding program with lines developed from this project will seek to provide a pipeline of improved non-transgenic cotton cultivars that address the primary constraints of organic cotton production in the major organic cotton growing region in the U. S. Without this potential pipeline, organic cotton producers are at risk of losing available planting seed options. This project focuses on introgression of thrips tolerance into high quality cotton varieties and developing integrated pest management solutions for production of new, conventional varieties. The project most significantly addresses the OREI legislatively-defined goal 8. "Developing new and improved seed varieties that are particularly suited for organic agriculture" in its primary objective of creating thrips-tolerant cotton cultivars. Goal 1, "Facilitating the development of organic agriculture production, breeding and processing methods" is also addressed in the objective of combining thrips resistance with drought tolerance and improved fiber quality. <P> Approach: The initial screening method uses greenhouse grown wheat to rear thrips for uniform, medium to excessive thrips pressure. Visual ratings, differential leaf surface area reduction, and a plant washing method to accurately recover thrips are used to calculate indicators of resistance. The method for no-choice screening uses cages to restrict movement of thrips between test plants, eliminating antixenosis as a mechanism of resistance. Accessions that show resistance in the free-choice testing are tested in no-choice screening. Standard methods that plot plant health against insect health indicators are used to identify the mechanism of resistance as tolerance or antibiosis. Existing F2 populations (G. barbadense accession TX110 x breeding program elites) from a thrips tolerant cultivar and 2 adapted breeding lines have been screened in the field and plants identified and selected that show resistance in the early seedling stage to the thrips complex and exhibit day-neutral flowering characteristics. F3 plant selections will be crossed to G. hirsutum backgrounds screened for drought tolerance and fiber quality characteristics and to cold tolerance selections exhibiting improved thrips tolerance. Tolerance of selections will be confirmed by paired-plot studies with and without approved products for thrips avoidance. Multi-location performance testing, including certified organic farms, will begin in the F4-F5 generation. The effectiveness of OMRI approved insecticides for managing western flower thrips infesting conventional and thrips tolerant cotton cultivars will be evaluated using factorial design with 4 replicates. Orthene will be included as a conventional standard for comparison purpose if the test is not conducted on an organically certified field. The compensatory ability of selected thrips tolerant and susceptible cotton cultivars (3 tolerant and 3 susceptible cultivars) to thrips-induced plant growth and maturity delays will be examined. Fruit retention will be monitored using standard COTMAN SQUAREMAN protocols throughout the growing season. The variation in carpel wall thickness among cultivars with varying levels of thrips tolerance will be quantified. Greenhouse screening for thrips tolerance uses a simple randomized block design measuring differences in leaf surface area biomass and is analyzed using SAS. A completely randomized design or randomized block design will be used for field trials depending on irrigation type. These designs will allow for statistical comparison between cultivars no matter the variable. Any cultivar developed that has potential use in organic cotton production will be registered with the Texas A&M Office of Technology and Commercialization. Breeder seed will be maintained by Texas AgriLife Research. Cultivars will be used for planting seed in organic cotton production. Recommendations on OMRI-approved material for early season insect control will be disseminated to organic cotton growers. Results from compensatory and carpel wall studies will be used in the cotton breeding program to develop a pipeline of potential cotton seed varieties for organic cotton production.