Yield and yield components of soybean cultivars grown in late season were statistically heavier than those grown in the early cropping season. The TGX 1830-20E, 1888-15F 1485-ID and 1740-2F cultivars were the heavy yielders and moderate in soil fertility enhancement in both seasons. The cultivars TGX 1838-12F and 1485-ID enhanced the soil fertility remarkably. Finally, further research is needed to integrate soybean production into the existing dominant farming system of South Eastern Nigeria including maize- soybean relay system for enhanced productivity and improved soil fertility. Это и многое другое вы найдете в книге Soybean cultivars and soil fertility (Ifeoma E. Christo)