The Effects of <i>Bradyrhizobium japonicum</i> Inoculation and Superphosphate Fertilizer on the Growth and Development of Lablab (<i>Lablab purpureus</i> L.)

Nutrient-poor savanna soils severely limit agricultural productivity in Africa, hindering crops and livestock intensification and threatening food security. Addressing these deficiencies is crucial to meeting the world’s growing food demands and ensuring sustainable agricultural development. The experiment was conducted in a greenhouse laid in a randomized complete block design with eight treatments, namely: (T1) control, (T2) 45 kg/ha superphosphate, (T3) 60 kg/ha superphosphate, (T4) 75 kg/ha superphosphate, (T5) Bradyrhizobium japonicum inoculant, (T6) Bradyrhizobium japonicum inoculant +45 kg/ha superphosphate, (T7) Bradyrhizobium japonicum inoculant +60 kg/ha superphosphate, and (T8) Bradyrhizobium japonicum inoculant +75 kg/ha superphosphate. The findings showed that the highest plant height was noted when lablab was supplemented with T4 treatment at day 21, while T2 of superphosphate had the highest leaf area. Conversely, soil supplemented with superphosphate at different levels and/or lablab seeds treated with Bradyrhizobium inoculant did not have a significant effect on the number of leaves. Overall, the application of superphosphate to the soil at different levels and treating lablab seeds with <i>Bradyrhizobium</i> inoculant did not have any significant effect on the plant height, number of leaves, and leaf area. On day 37, the highest leaf chlorophyll was recorded on T1 and became constant amongst all the treatments as the growth progressed. From the current study, it is concluded that growing lablab in a controlled environment would benefit subsistence farmers and rural communities for its leaves consumed as vegetables and ultimately ensure food security.