The profit potential of soybean production rotation systems in Arkansas

The objective of this study was to provide agronomic, nematode, and economic analysis of alternative production rotation systems for soybeans (Glycine max L. Merr.) on a silt loam soil association in Arkansas. Monocropped soybeans and soybeans double-cropped with wheat (Triocum aestivam L.) was included as well as grain sorghum (Sorghum bicolor L. Moench) under dryland conditions in order to reduce soybean cyst nematode (SCN, Heterodera glycine Ichinohe) populations. A total of seven crop rotations and eleven treatments that included alternative tillage conditions and wheat stubble management practices were analyzed using data from 1980-1984 experiments conducted at the Arkansas Cotton Branch Experiment Station on a silt loam Loring-Calloway-Henry Association (Alfisols). Although crop rotation was effective for nematode suppression, yields for double-cropped soybeans were comparable to soybean yields under monocropped' continuous management practices. Economic results indicated that average net returns of $338.50 per hectare (about $137 per acre) were highest for the continuous double-cropped wheat-soybean production management systems which combine the conventional tillage method with burning of wheat stubble. For the conditions analyzed and level of SCN present, this research provides evidence that control of the soybean cyst nematode through rotation practices that utilize grain sorghum is not economically efficient where continuous double-cropped wheat-soybeans systems can be incorporated.