Location: Crop Production Systems Research2015 Annual Report
1a. Objectives (from AD-416):
Objective 1: Optimize early soybean production system and associated pest management strategies for the Mid-Southern United States. Objective 2: Develop innovative cotton management approaches that will optimize physiological responses of the cotton plant to environmental factors so that it can make the most efficient use of production inputs to improve lint yield and fiber quality. Sub-objective 2.1: Quantify yield, fiber quality, growth and development for varying cotton plant population densities with adequate and less-than-adequate N fertilization, and under irrigated or dryland production. Sub-objective 2.2: Quantify yield, fiber quality, growth and development for varying cotton varieties grown in both twin-row and single-row planting patterns under irrigated or dryland production. Sub-objective 2.3: Assess benefits of transgenic and non-transgenic cotton-soybean rotation systems on soil properties, weeds, yield, and seed and fiber quality in the Mississippi Delta. Objective 3: Assess the benefits of new drought tolerant, multiple herbicide-resistant, and insect-resistant (stacked gene traits) in current or new production systems. Objective 4: Assess impacts of transgene and glyphosate applications on soil microbial communities, plant-microbe interactions, as well as plant health and productivity in corn and soybean. Objective 5: Identify new and/or alternative crops for the Mid-South, determine their potential, and develop management strategies for integration and production.
1b. Approach (from AD-416):
The purpose of this project is to develop productive, profitable, and sustainable crop production systems for three of the mid-southern major row crops (soybean, cotton, and corn) that increase yield, improve quality, and reduce production costs. Over the next five years, we will conduct customer-driven basic and applied research aimed at improving regional-specific cropping systems that are profitable, conserve natural resources, provide effective pest control, and make efficient use of production inputs. The specific production practices to be researched in these 3 major crops include row patterns and row spacing, seeding rates, new genotypes, nutrient management, crop rotations, irrigation, planting dates, and transgene and glyphosate effects on plant health and productivity of corn and soybean. In addition, alternative crops that could be produced using existing equipment and fit into rotation systems will be researched.
3. Progress Report:
The results from the agronomic, physiological, and crop culture studies gave insight to physiological mechanisms leading to cotton lint yield and fiber quality differences among diverse varieties and different cultural practices. Irrigation or sufficient soil moisture was necessary to get the most efficient use of nitrogen (N) fertilization and vice versa, regardless of the cotton seeding rate. Cotton grown in twin-row production system produced similar yields and fiber quality as cotton produced in the more traditional wide row pattern regardless of the irrigation regime or growth regulator applications. Growth and yield of cotton was superior when grown following soybeans rather than following cotton. Field data collection on soybean cultivars grown in early planting systems was successfully completed and laboratory analysis of harvested seed is underway. Complete data analysis will follow. A lack of drought due to substantial rainfall during the first growing season will necessitate a third growing season to complete the experiment on drought tolerant corn hybrids. Currently, the second planting has been made and data collection is underway. The initial experiment to evaluate grain sorghum hybrids, seeding rates, row-types, and irrigation of grain sorghum has been completed and published. Three more experiments are currently underway to determine the effects of 1) nitrogen rates and hybrids, 2) reduced seeding rates on yield and yield components, and 3) possible hybrid differences in resistance to sugarcane aphid, a new pest to appear in the crop. Assessment of glyphosate-resistant gene and glyphosate applications on soil microbial communities, plant-microbe interactions, as well as plant health and productivity in corn and soybean is underway. Soil and plant samples were collected and are being analyzed. A field experiment on guar (alternate crop for the mid-south) production was initiated in 2015 and field data is being collected.
1. Twin-row cotton production system. Most mid-south cotton producers no longer just grow cotton on all their planted acres; instead many acres are rotated to corn or soybean production. Many regional producers have also begun adapting twin-row planting patterns on their corn and soybean acreage. To make most efficient use of the twin-row planter, producers would prefer to plant as many acres with that twin-row planter as possible, including cotton acreage. An ARS scientist in the Crop Production Systems Research Unit at Stoneville, MS, examined how cotton lines varying in leaf shape and leaf size perform when grown under either twin-row (two rows spaced about 7 to 15 inches apart and centered on a 40 inch bed) or single row (spaced 40 inch apart) production systems. The response to twin-row planting compared to single row planting was consistent across all the cotton lines of varying leaf shape and size. Despite increased early season leaf area production and sunlight interception, no differences between planting patterns were detected for lint yield, yield components, or fiber quality traits. Although, twin row production did not improve yields or fiber quality, it did not hurt them either. This finding may allow producers to use the same planting pattern (twin-row) for multiple crops such as cotton, soybean, or corn.
2. Grain sorghum production in mid-south. Grain sorghum is not a major crop in the Mississippi Delta but has consistently been grown on a limited number of acres. Research on the crop in Mississippi, over the past 15 years, has been extremely limited. Being known to be drought tolerant though, makes it an attractive alternative cash crop that could help reduce irrigation demands on a decreasing ground water supply. An ARS scientist in the Crop Production Systems Research Unit at Stoneville, MS, conducted a field study to examine effect of various cultural practices on grain sorghum production. The results showed that seeding rates, twin-row vs. single-row seedings, and irrigation had no impact upon grain sorghum yields or yield components in seeding rates above 150,000 kernels per hectare. This was due to grain sorghum’s drought tolerance and strong ability to compensate among the various yield components to stabilize the yield. Rather than fallowing land for a year to conserve irrigation water, grain sorghum with a feeding value of 98% of corn may provide a source of income as a non-irrigated rotational crop in the Mississippi Delta region.
3. Late-season grass weed management in glyphosate-resistant soybean. Emergence of grasses late in the season has become a problem in glyphosate-resistant (GR) soybean production in the southern U.S. To reduce the risk of late-season weeds and to sustain crop yields, it is imperative to develop strategies to manage these weeds. ARS scientists in the Crop Production Systems Research Unit at Stoneville, MS, conducted a 3-yr field study to determine the efficacy of pyroxasulfone applied as preemergence coupled with post-harvest herbicides on late-season grass weeds and yield in twin-row GR soybean. Pendimethalin and paraquat were applied after soybean harvest (post-harvest) and five pyroxasulfone-based herbicides were applied in-crop in twin-row soybean. Browntop millet, Digitaria spp., and junglerice densities at 2 weeks after late postemergence, grass weed dry biomass at harvest, and soybean yield were similar regardless of post-harvest herbicides in all three years. At 2 weeks after late postemergence, browntop millet, Digitaria spp. and junglerice densities were reduced in all five in-crop herbicide treatments compared with no herbicide plot in all three years. The five herbicide treatments reduced grass weed dry biomass by at least 87, 84, and 99% in 2011, 2012, and 2013, respectively. Soybean yield was higher with all five in-crop herbicide treatments compared to no herbicide control in all three years. This study demonstrated that these grass weeds can be reduced with pyroxasulfone-based in-crop herbicide programs in twin-row GR soybean.
Reddy, K.N., Bryson, C.T., Nandula, V.K. 2015. Late-season grass weed management with in-crop and post-harvest herbicides in twin-row glyphosate-resistant soybean. American Journal of Plant Sciences. 6:213-218.
Pettigrew, W.T., Zeng, L. 2014. Interactions among irrigation and nitrogen fertility regimes on Mid-South cotton production. Agronomy Journal. 106:1614-1622.
Bauer, P.J., Pettigrew, W.T., Campbell, B.T. 2014. Response of four cotton genotypes to N fertilization for root hydraulic conductance and lint yield. Journal of Cotton Science. 18:362-366. Available: http://journal.cotton.org.
Pettigrew, W.T., Dowd, M.K. 2014. Nitrogen fertility and irrigation effects on cottonseed composition. Journal of Cotton Science. 18:410-419.
Zeng, L., Pettigrew, W.T. 2015. Combining ability, heritability, and genotypic correlations for lint yield and fiber quality of Upland cotton in delayed planting. Field Crops Research. 171:176-183.
Bellaloui, N., Bruns, H.A., Abbas, H.K., Mengistu, A., Fisher, D.K., Reddy, K.N. 2015. Agricultural practices altered soybean seed protein, oil, fattyacids,sugars, and minerals in the Midsouth USA. Frontiers in Plant Science. 6(31):1-14.
Reddy, K.N., Duke, S.O. 2014. Soybean mineral composition and glyphosate use. In: Processing and Impact on Active Food Components in Food, V.R. Preedy, Ed.,Elsevier, Inc., London. p. 369-376.
Reddy, K.N., Huang, Y., Lee, M.A., Nandula, V.K., Fletcher, R.S., Thomson, S.J., Zhao, F. 2014. Glyphosate-resistant and glyphosate-susceptible Palmer amaranth (Amaranthus palmeri S Wats.): hyperspectral reflectance properties of plants and potential for classification. Pest Management Science. 70:1910-1917.
Bruns, H.A. 2014. Stacked -gene hybrids were not found to be superior to glyphosate resistant or Non-GMO corn hybrids. Crop Management. p. 1-5.
Bruns, H.A. 2015. Irrigation seedling rates, and row type effects on grain sorghum in the Midsouth. Agronomy Journal. 107:9-12.
Bruns, H.A. 2015. Ear leaf photosynthesis and related parameters of transgenic and non-GMO maize hybrids. International Journal of Agronomy. 2015:1-5. doi:10.1155/2015/731351.
Nandula, V.K., Poston, D.H., Koger, C.H., Reddy, K.N., Reddy, K.R. 2015. Morpho-physiological characterization of glyphosate-resistant and -susceptible horseweed (Conyza canadensis) biotypes of US Midsouth. American Journal of Plant Sciences. 6:47-56.
Mengistu, A., Kelly, H.M., Bellaloui, N., Arelli, P.R., Reddy, K.N., Wrather, A.J. 2014. Tillage, Fungicide, and Cultivar Effects on Frogeye Leaf Spot Severity and Yield in Soybean. Plant Disease. 98(11):1476-1484.