Impact of Rhizobium Inoculation on the Growth and Yield of Soybean Varieties in Sudan Savanna, Nigeria

Soybean is an essential legume in sub-Saharan Africa, valued for its nutritional and economic benefits. However, its productivity in the Sudan Savannah of Nigeria is often constrained by soil nutrient deficiencies, particularly nitrogen. The use of rhizobium inoculation has emerged as an effective biological approach to enhance nitrogen fixation, promoting better growth and yield. The study aimed to evaluate the impact of rhizobium inoculation on two soybean varieties under Sudan Savannah conditions. Field experiments were conducted during the rainy season of 2021 at the Teaching and Research Farm of Aliko Dangote University of Science and Technology Wudil (Latitude: 11.9331° N, Longitude: 8.5216° E) and the Faculty of Agriculture Bayero University Kano (Latitude: 12.0027° N, Longitude: 8.5914° E) in Sudan Savannah, Nigeria. The experiments were conducted using a Randomized Complete Block Design (RCBD), involving treatments of two rhizobium inoculations (inoculated and un-inoculated) and two soybean varieties (TGX1447-2E and TGX1885-10E). Data were collected on number of nodules, fresh weight of nodules, dry weight of nodules, number of pods per plant, pod weight per plant (g), shelling percentage per plot, 100 seed weight, yield per plant, and yield per hectare. The study revealed that rhizobium inoculation affected the growth and yield characteristics of soybean varieties in the research areas. The growth and yield characteristics increased with rhizobium inoculation at both locations. The result also revealed that TGX 1448-2E had a significant advantage over TGX 1885-10E. The research therefore recommends inoculation of Soybeans and the application of phosphorous at 40kg/ha to optimize soybean production in similar agro-ecological contexts.