Location: Coastal Plain Soil, Water and Plant Conservation Research
2018 Annual Report
Objectives
Objective 1. Determine the ability of cotton germplasm to withstand soil water deficits, identify and characterize drought tolerance genes, and develop innovative management practices for optimizing use of the improved genotypes in production systems.
Sub-objective 1A. Identify genotypes with fiber length stability when subject to water deficit stress during fiber elongation.
Sub-objective 1B. Identify cotton genotypes that withstand soil water deficits.
Sub-objective 1C. Evaluate variable rate irrigation using crop feedback for site-specific irrigation management of cotton in the Southeastern U.S. Coastal Plain.
Objective 2. Develop and evaluate new cotton germplasm with increased genetic diversity, improved fiber quality, and lint yield stability traits.
Approach
New technologies and new genetic resources are needed to help the nation’s cotton producers face increasing economic and environmental challenges. The proposed research will contribute to the industry’s ability to meet the nation’s fiber needs and become more competitive in world markets. Since water deficit stress is a serious limitation to cotton production, much of this research will be aimed at finding solutions to lessen the impact of this environmental stress. The research has two objectives: (1) determine the ability of cotton germplasm to withstand soil water deficits, identify and characterize genetic variation for drought tolerance, and develop innovative management practices; and (2) develop new cotton genetic resources with increased genetic diversity, improved fiber quality, and lint yield stability. In this research, we will conduct genetic studies on the effect of water deficit stress on fiber length and yield, determine how best to use proximal sensing data collected from high throughput phenotyping platforms, design innovative double crop cotton production systems, and develop new cotton genetic resources. Research methods include field experiments and statistical analyses using modern analytical equipment and innovative analytics. Research products include new knowledge of genetic variation for fiber length stability under water deficit stress, protocols for using proximal sensing data collected from high throughput phenotyping platforms as a water deficit stress breeding selection tool, new water efficient cotton cropping systems, and high quality cotton germplasm containing exotic introgression. All segments of the cotton industry and southern rural economies will benefit from the findings of this research.
Progress Report
Water deficit stress research. The first year of two 2-year field studies were initiated in 2018. The first field study is designed to determine the impact of water deficit stress on fiber length development. Bolls will be intensively sampled among a group of diverse genotypes in well watered and water deficit stress field plots every five days through the first 35 days of fiber development. Fiber lengths will be measured across the time series to develop growth curves for each genotype. This research should provide new insights into genetic diversity for fiber length under water deficit stress. The second field study is designed to determine if canopy temperature can be used to determine genotypic differences in drought tolerance. Research was initiated in 2017 and continued in 2018 to develop methods to improve the efficiency of collecting canopy temperature data with high throughput phenotyping equipment. Using a drought susceptible genotype and a drought-tolerant genotype with a known drought-tolerance mechanism, intense canopy temperature data collection was initiated to determine soil water levels, crop growth stage, and local weather conditions which provide the best opportunity to differentiate genotypes differing in drought tolerance. This research should provide new insights into optimizing high throughput phenotyping data collection and analysis.
Cotton germplasm development research. A multi-location (ARS Florence, South Carolina, ARS Maricopa, Arizona, and ARS College Station, Texas) field trial was initiated to evaluate advanced breeding lines derived from exotic landraces. Agronomic and fiber quality performance data will be used to support germplasm line release decisions to provide industry with new genetic diversity. Also, a project to develop genetic populations containing different levels of exotic introgression is being initiated. Initial crosses are being made to generate F1 seed. The introgression populations developed by the end of this project plan will provide a rich genetic resource to further study exotic landrace introgression in cotton. Together, the germplasm lines and introgression populations will also provide the cotton industry new breeding stock containing previously untapped and valuable genetic diversity.
Accomplishments
