Consortium biofertilizers to economise nutrient use and sustain productivity in cassava (Manihot esculenta Crantz)

ABSTRACT

Climate change events and the COVID-19 pandemic have brought to focus the significance of cassava as a supplementary food crop worldwide. However, the high yield potential of the crop necessitates timely and adequate enrichment of the soil with nutrient inputs. Consortium biofertilizers offer a viable option for reducing intensive fertilizer use to sustain soil health and productivity in cassava. The efficacy of a liquid consortium biofertilizer, specifically a plant growth-promoting rhizobacteria (PGPR) Mix - I, in economizing nutrient use in cassava was evaluated in a 4 x 3 factorial randomized block design, replicated thrice. The treatments consisted of combinations of four levels of biofertilizers and three levels of nutrients. Biometric and yield observations were recorded, and soil properties were analyzed before and after the harvest of the crop. The results showed that the liquid biofertilizer consortium at a concentration of 5% + 75% of the recommended dose, with 37.537.575 kg NPK/ha as chemical fertilizers, recorded significantly superior tuber yield in cassava. Considering the economics, the application of the PGPR liquid formulation (5%) thrice (basal, 2 and 4 MAP) along with 37.537.575 kg NPK/ha, or at a concentration of 2% with 5050100 kg NPK/ha, realized higher benefit-cost ratios and can be recommended for use in cassava.