Effect of Integrated Nutrient Management on Soil Health, Soil Quality, and Production of Cowpea (Vigna unguiculata L.)

Abstract

The integrated application of inorganic fertilizers, organic fertilizers, and biofertilizers helps sustain the nutrient pool and benefits the soil quality, thereby boosting plant health. The effect of different combinations of biofertilizers (consortium biofertilizer [CBF]—non-rhizobial PGPR), inorganic fertilizers, and organic fertilizers on soil health, growth, and yield of cowpea was evaluated by conducting a field experiment. The application of N₁₀₀ FYM + CBF resulted in significantly higher populations of bacteria, fungi, PSB, and diazotroph, as well as soil dehydrogenase and alkaline phosphatase enzyme activities. However, the application of N₁₀₀ FYM recorded a significantly higher actinomycetes population. The application of N₁₀₀ FYM + CBF resulted in significantly higher soil OC, available nitrogen, phosphorus, and potassium. The soil pH was recorded to be highest in control, and soil EC was recorded to be lowest in control. The plant uptake of nitrogen, phosphorus, and potassium was significantly higher with N₅₀ FYM + NP₅₀ + CBF. The root–shoot biomass, number of leaves, nodules/plant, number of pods/plants, pod biomass, pod length, and pod width were significantly higher in treatment having N₅₀ FYM + NP₅₀ + CBF. However, the height of the plant, number of branches, and biomass of leaves were highest in treatment with N₂₅ FYM + NP₇₅ + CBF. The pod and stover yield were significantly higher in treatment with N₅₀ FYM + NP₅₀ + CBF. The results showed that the integrated application of non-rhizobial PGPR along with organic and inorganic fertilizer helps to improve overall soil health, quality, and plant growth of forage cowpea contributing to an increase in crop yield.