精练剂资料

ABSTRACT

FOOTE, WILLIAM RAY. Improving Cotton (Gossypium hirsutum L.) Production through Non-Traditional Practices. (Under the direction of Keith Edmisten.)

Cotton producers in the southeastern United States are highly competitive with foreign producers, despite being subjected to higher labor, shipping, and regulatory costs. Regardless, in order to remain competitive, fluctuation in market prices and input costs force producers to continually search for innovative methods to produce higher yield without incurring additional costs. In these studies, several aspects of cotton production were identified and researched to evaluate their potential cost savings and yield improvement. Experiments were designed to: increase land use and net returns through intercropping cotton (Gossypium hirsutum L.) and wheat (Triticum aestivum L.); reduce nitrogen costs by using winter legume cover crops; improve water conservation through furrow diking; and improve sensor-based variable nitrogen prescription rates by determining the effects of mepiquat chloride on normalized difference vegetative index values. Also, relay intercropping of cotton in wheat was researched as an alternative to traditional double-cropping in North Carolina.

The intercropping system produced wheat yield ranging from 65% to 85% of conventional wheat plantings, while maintaining cotton yield equal to mono-culture cotton. In addition, the intercropping system demonstrated the ability to suppress the population of thrips (Thysanoptera:Thripidae), with an economic return equaling that of conventional cotton planting and even exceeding that of double-cropped soybean. Furthermore, the use of legumes as a winter cover crop and a green manure was researched to determine the ease of establishment in un-harvested cotton in the fall and the ability to supply the total seasonal nitrogen requirement of cotton. Austrian winter pea (Pisum sativum L.) and crimson clover

第1页下一页