1a. Objectives (from AD-416)
1) Develop genetic resources and cropping practices that increase cotton water-use efficiency. 2) Develop new cotton genetic resources with improved fiber quality, lint yield stability, and adaptation. 3) Develop management techniques for cotton grown with conservation tillage after a winter biofuel crop.
1b. Approach (from AD-416)
Basic genomic and applied research will be conducted on improving cotton water use efficiency. In this research, molecular techniques will be used to search for genes that may provide more tolerance to water-deficit stress. Field studies will be conducted to screen cotton germplasm for water-deficit stress tolerance and to determine how agronomic practices affect plant water status. Contemporary plant breeding methods will be used to develop and release high yielding germplasm lines with improved fiber quality. Germplasm combining ability studies as well as studies determining genetic mechanisms for improved fiber quality will be conducted to accelerate the germplasm development program. We will evaluate cotton production potential when double cropped with winter crops harvested for biofuels. Winter crop biomass and energy content, cotton seedling establishment, and cotton fertility needs will be assessed.
3. Progress Report
This project was initiated in January of this year and follows the terminated project 6657-21000-005-00D ‘Enhancing the sustainability of cotton production in the southeast USA’. Gene Identification Research: Research was conducted on identifying the genes in cotton that provide the genetic code for the aquaporins in cotton. Aquaporins are proteins in cell membranes that facilitate water movement in and out of cells. Thus far, we have identified 60+ putative aquaporin genes and have found that the expression of the genes for some of these aquaporins depends on plant tissue types. We anticipate that this research will provide useful targets for the genetic improvement of water use efficiency in cotton. Cotton Germplasm Enhancement Research: Developing new cotton cultivars with improved fiber quality and lint yield potential is essential to maintain a sustainable and profitable US cotton industry. Research was initiated to screen cotton genotypes for tolerance to water deficit stress and to develop new cotton genetic resources with improved fiber quality, lint yield stability, and adaptation. Seed of approximately 300 cotton landrace accessions were requested and received from the US cotton germplasm collection so that experiments could be established to screen these accessions for tolerance to water deficit stress. Field genetic studies were established on cotton yield and fiber properties. These germplasm enhancement efforts will provide the industry optimum breeding schemes for high yield and fiber quality while also providing new cotton germplasm with increased genetic diversity, high yield, and excellent fiber quality. Fertilizer Management Research: Soil fertility, especially the availability of nitrogen in the soil, impacts the efficiency of cotton to use water from an irrigation or rainfall event. Field experiments were established to determine whether the root hydraulic conductance response of cotton to fertilizer nitrogen is genotype specific. Information gained from this research will be used in the development of improved cotton gentoypes. Data collection from this experiment is continuing. We also continued our research on phosphorus recovered from animal manures. Technologies were developed at this location to recover phosphorus from animal manure in a form concentrated enough to be used as a fertilizer material. Plant and soil samples were collected from a field study designed to evaluate the plant availability of two particle sizes of phosphorus recovered from swine wastewater. Data collection from this experiment is continuing. Cotton Following Winter Biomass Crops: Field studies were initiated to determine the potential of using species of plants currently used as winter cover crops in cotton as sources for biofuel. Plant samples have been collected from these trials and they will be analyzed for energy content and their suitability as a bioenegy feedstock blend with other biomass sources (i.e., animal manures) will be determined.
1. Release of High Fiber Quality Germplasm Lines of Cotton: The demand for high quality cotton cultivars continues to increase to meet the needs of the fiber processing and textile industry. In 2009, we co-released two sets of Upland cotton germplasm lines with excellent yield potential and superior fiber quality. One set of germplasm lines was co-released with the ARS Crop Genetics and Production Research Unit in Stoneville, MS (CRIS #6402-21000-033-00). A second germplasm line was co-released with the ARS Crop Germplasm Research Unit in College Station, TX (CRIS #6202-21000-031-00). The lines serve to broaden the genetic base of cotton to facilitate continual, long-term genetic improvement and cultivar development. These lines are now available for public and private breeders to use to develop high yield and high quality cotton varieties. High yield and high quality cotton production will enhance cotton farm profits and productivity of textile mills.