Evaluation of arbuscular mycorrhizal fungi on the growth and yield of soybean [Glycine max (L.) Merrill]

Abstract

Soybean [Glycine max (L.) Merrill] is a vital grain legume and oilseed crop, valued for its protein and oil content, and increasingly cultivated in Nigeria’s rainforest and savanna agro-ecological zones. Its productivity is often limited by poor soil nutrient availability, particularly phosphorus. Arbuscular mycorrhizal fungi (AMF) enhance nutrient uptake, water relations, and stress tolerance, thereby improving crop yield. This study evaluated the effects of AMF inoculation on soybean growth and yield under field conditions at the Federal University of Agriculture, Abeokuta, Nigeria. A split-plot randomized complete block design was used, with two soybean cultivars (TGx 1448-2E and TGx 1440-1E) as main plots and four AMF treatments (Funneliformis mosseae, Rhizophagus irregularis, Clariodeoglomus etunicatum, and a non-inoculated control) as subplots. Plant growth variable data was collected and subjected to analysis of variance and significant means were separated using Fisher’s Least Significant Difference at p < 0.05. Results showed that TGx 1448-2E recorded higher leaf numbers, early leaf area, and yield attributes, while TGx 1440-1E attained greater plant height at 8 weeks after sowing. Inoculation with Funneliformis mosseae and Rhizophagus irregularis produced the most significant improvements in plant growth and yield compared to the control. These findings show the potential of indigenous AMF, particularly Funneliformis mosseae, as sustainable biofertilisers for enhancing soybean productivity in phosphorus-deficient soils. The study provides a foundation for integrating AMF inoculation into soybean production systems, contributing to food security, soil fertility improvement, and climate-resilient agriculture in tropical environments.