Soybean seed yield and quality under an ultra-short-season production system

Drought is a major yield-limiting factor for soybean [Glycine max.] in the southern U.S.A. The ultra-short-season production system (USSPS), which uses maturity group (MG) 00 through I cultivars planted in April in Arkansas, may minimize severe yield reduction by drought since this system allows growers to harvest soybeans before severe drought occurs. The objective of this study was to evaluate yield potential and seed quality of Northern MG 00 through I soybean cultivars in a mid-South environment. Average yields of MG 00, 0 and I were 2954, 3585, and 3782 kg ha-1, respectively, under irrigated conditions. Average yield under dryland production was significantly lower than that under irrigated production. However, some cultivars yielded significantly higher than the Arkansas state average (1881 kg ha-1). Infection by seedborne fungi was minimal for all cultivars. Average germination rates under irrigated and non-irrigated production were 71, 71, and 68% for MG 00, 0, and I, respectively. There were large genotypic variations for seed yield and germination rate, suggesting cultivar selection is important for MG00 through I cultivars to be successful under the USSPS. These results show the potential of USSPS to produce a profitable crop in 79 to 100 d in the mid-South under both irrigated and dryland conditions