2008 Annual Report
1a.Objectives (from AD-416)
1) Optimize cotton production systems for the southeastern U.S.A. that incorporate soil conservation and sustainable technologies, such as winter cover crops, reduced tillage, and poultry waste. Subobjectives are (a) to develop improved management practices in cotton production systems that include poultry litter or materials derived from poultry litter; (b) assess the feasibility of using late-summer legumes for soil improvement in rotations with cotton; and (c) relate water use to within-canopy boll size and quality distribution in a conservation production system and determine how patterns of water use affect whole crop fiber quality of genotypes differing in genetic potential for fiber properties..
2)Identify sources of traits to improve cotton performance in production systems in the southeastern USA and introgress the associated genes into enhanced germplasm suitable to be made available to cotton breeders for variety development.
1b.Approach (from AD-416)
Cotton production and processing are an important part of the economy of the southeastern U.S.A., and development of sustainable production systems and improved germplasm will be key to sustaining and enhancing the industry. We intend to conduct research that will result in improved cotton production systems that provide higher yield, improved fiber processing quality, and lessen risk of non-point source pollution to the environment. We will.
1)identify management options and search for genetic traits that can be used to overcome factors that inhibit optimum productivity in conservation systems;.
2)evaluate the agronomic and environmental value of potential resources (poultry litter and products extracted from litter; summer legume cover crops) available to growers in the southeast; and.
3)evaluate genotypes and develop germplasm with enhanced fiber yield for profitable production and improved fiber properties for efficient yarn and textile processing into consumer acceptable products. Methods consist of field, greenhouse, and laboratory investigations. The expected benefits of this research are crop management systems with higher yield, more environment-friendly growing practices, and the development of germplasm with improved fiber properties which will benefit all segments of the cotton industry, including cotton farmers, agricultural supply companies, ginners, and mills.
This research contributes to the goals of National Program 305, Crop Production, Problem Statement 1A.1, Develop Integrated Strategies for Soil, Water, and Nutrient Management for Optimal Yield and Economic Returns in Annual Cropping Systems, Subcomponent 1A, Annual Cropping Systems, Component 1, Integrated Sustainable Crop Production Systems.
Agronomic Research: Data analysis was completed on experimental results from a two-year field study evaluating within-canopy distribution of cotton fiber quality. Among other conclusions, this research was the first to describe the within-canopy distribution of fiber sucrose and salt content; two variables that influence the efficiency of fiber processing and yarn quality. A paper entitled ‘A comparison of two cotton cultivars differing in maturity for within-canopy fiber property variation’ has been submitted to Crop Science. Field and laboratory data were collected from a study to evaluate the nitrogen contribution of two summer legumes to a succeeding cotton crop. Analysis of the data suggests that, though substantial nitrogen accumulation occurs with summer legumes, rotations with these crops would not be advisable for cotton since most of the nitrogen was lost through the winter and early spring. A draft manuscript was prepared and is currently in review by coauthors. In our recovered phosphorus from animal manure research, data were analyzed from greenhouse experiments comparing soil movement of phosphorus recovered from animal manures to broiler litter and commercial fertilizer. Data was collected in the fall of 2007 from a field experiment using phosphorous recovered from animal manure as a fertilizer source for cotton. The results were inconclusive because of field variability, so a new field was prepared during the summer of 2008 which will be used for this line of research in the next three cotton growing seasons.
Cotton Genetics Research: Yield and fiber quality field performance data were collected on 90 preliminary and 108 advanced cotton breeding lines. Among the advanced cotton breeding lines evaluated, 4 were selected for further performance testing in the South Carolina Official Cotton Variety Trial and the Regional Breeder Testing Network Trial to determine if they should be officially released. Agronomic and fiber quality data were collected from a study to evaluate the type of gene action controlling yield and fiber quality properties. In a Crop Science manuscript, we report that breeding methods predominantly used over the last 50 years have capitalized on additive gene action while unintentionally ignoring non-additive gene action. This study suggests that cotton breeders should consider incorporating alternative breeding methods to increase yield potential by capturing the positive effects of non-additive gene action. With the recent hiring of a post doctoral molecular biologist, experiments are underway to study and identify genes in cotton possibly related to drought tolerance.
Release of PD 99035 and PD 98066 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 2007, we officially released two Upland cotton germplasm lines with superior fiber quality. The lines provide public and private breeders genetic resources for concurrent improvement of fiber quality and yield performance. The lines serve to broaden the genetic base of cotton to facilitate continual, long-term genetic improvement and cultivar development. By publicly releasing and distributing seed of PD 99035 and PD 98066, these lines can be used to develop new, commercial cultivars with improved fiber quality potential. The release of these germplasm lines contributes to the goals of National Program 305, Crop Production, Problem Statement 1A.1, Develop Crop Production Systems that are Productive, Profitable, and Environmentally Acceptable, Subcomponent 1A, Annual Cropping Systems, Component 1, Integrated Sustainable Crop Production Systems.
Soil Sampling for Fertilizer Recommendations in Conservation Tillage. A representative soil sample is a critical component of soil testing for fertilizer and lime application recommendations. We conducted this research to determine if modifications from established sampling depths were needed for collecting soil samples for recommendations in conservation tillage systems that included using a paratill subsoiler. We found that for phosphorous (P) and potassium (K), either a shallow (0 – 3 in) or deep (0 – 6 in) sample was acceptable in this tillage system. However, for lime, a shallow sampling depth was a better sampling depth in the years following a lime application. With rapidly rising costs for these amendments, this information is important to growers who need to maximize economic returns from crop production inputs. This research contributes to the goals of National Program 305, Crop Production, Problem Statement 1A.1, Develop Integrated Strategies for Soil, Water, and Nutrient Management for Optimal Yield and Economic Returns in Annual Cropping Systems, Subcomponent 1A, Annual Cropping Systems, Component 1, Integrated Sustainable Crop Production Systems.
Improving the Precision of Cotton Cultivar Evaluation Trials on Variable Soils. Inherent soil variability in fields where cotton cultivar evaluation trials are conducted can reduce the ability of researchers to identify superior lines. We conducted this research to evaluate techniques that may increase the ability to statistically separate cotton cultivars for yield and fiber quality traits. We found that precision can be increased by using a two-step approach in which first, experimental data are evaluated to detect the amount of variability due to soil, and second, to adjust means if necessary using statistical techniques to account for the soil variability. Farmers depend on accurate cultivar evaluations by public scientists for choosing varieties to grow. These methods provide researchers a method to increase the precision of their experiments so farmers can make better planting decisions. This research contributes to the goals of National Program 305, Crop Production, Problem Statement 1A.1, Develop Crop Production Systems that are Productive, Profitable, and Environmentally Acceptable, Subcomponent 1A, Annual Cropping Systems, Component 1, Integrated Sustainable Crop Production Systems.
Recovered Phosphorous from Swine Wastewater. Scientists at this laboratory developed a method of recovering phosphorous (P) from animal manure to reduce the environmental impact of this nutrient in regions with large animal feeding operations. In this research, we determined the value of the recovered P as a fertilizer material. We found the material can be used as a readily available fertilizer source for plant production when applied in small particles (0.5 - 1.0 mm). The material was not readily available when applied to soil as large particles (2.0 - 4.0 mm), which suggests it may be a good source as a slow-release fertilizer. These results.
1)may enhance economic returns when adopting animal manure treatment, and.
2)are important because world P reserves are a finite resource; this research demonstrates the potential of recovered P as fertilizer. This research contributes to the goals of National Program 305, Crop Production, Problem Statement 1A.1, Develop Integrated Strategies for Soil, Water, and Nutrient Management for Optimal Yield and Economic Returns in Annual Cropping Systems, Subcomponent 1A, Annual Cropping Systems, Component 1, Integrated Sustainable Crop Production Systems.
5.Significant Activities that Support Special Target Populations
|Number of the New MTAs (providing only)||7|
|Number of New Germplasm Releases||2|
|Number of Web Sites Managed||1|
|Number of Non-Peer Reviewed Presentations and Proceedings||3|
Bauer, P.J., Szogi, A.A., Vanotti, M.B. 2007. Agronomic effectiveness of calcium phosphate recovered from liquid swine manure. Agronomy Journal. 99:1352-1356.
Campbell, B.T., Bauer, P.J. 2007. Improving the precision of cotton performance trials conducted on highly variable soils of the southeastern USA Coastal Plain. Plant Breeding 126:622-627.
Bauer, P.J., Frederick, J.R., Busscher, W.J., Novak, J.M., Fortnum, B.A. 2008. Soil sampling for fertilizer recommendations in conservation tillage with paratill subsoiling. Crop Management doi:10.1094/CM-2008-0218-01-RS.
Campbell, B.T., Bowman, D.T., Weaver, D.B. 2008. Heterotic effects in topcrosses of modern and obsolete cotton cultivars. Crop Science 48:593-600.