Response of Bioformulations and Inorganic Fertilizers for Productivity, Quality, and Soil Microbial Activity of Banana in the Subtropics

The present investigation assessed the impact of bioformulations and inorganic fertilizers on growth, yield, soil quality, leaf nutrient, and soil microbial status of banana in the subtropics during two consecutive seasons during 2019-2021. Ten different treatments were examined, namely, T1-absolute control (only farm yard manure); T2-recommended dose of nitrogen and phosphorus only; T3-recommended dose of fertilizers (100% NPK); T4-nitrogen, phosphorus, and organo-mineral formulation-K; T5-50% recommended dose of fertilizers +50% CSR Bio; T6-100% CSR Bio; T7-50% RDF +50% FUSICONT; T8. 100% FUSICONT; T9-100% CISH Bioenhancer; T10-50% RDF +50% CISH Bioenhancer in randomized block design with three replications. Among all treatment, the maximum pseudostem cross-sectional area (PCSA), leaf number (LN), functional leaf area (FLA), leaf area index (LAI), leaf retention index (LRI), fruit yield (FY), total soluble solids (TSS) of ripe fruit, TSS/acid ratio (T:A), and productivity efficiency (PE) were recorded in T3. In T1, there were increments of 39.62%, 16.07%, 48.05%, 47.59%, 15.87%, 139.6%, 9.36%, 22.95%, and 77.77% in the aforementioned parameters, respectively. The minimum crop duration from planting to harvesting was also noted in T3. Over T1, the 23 days early flowering and fruit maturity were observed in the T3. The available nitrogen (N), phosphorous (P), and potassium (K) were found to be maximum in T3-treated soil. Comparisons with the T1 value taken as 100% showed there were 131.55%, 35.47%, and 163.31% more N,P, and K content, respectively. Similarly, there was 93.27%, 47.82%, and 40.59% higher N, P, and K content in leaves in T3, respectively. The highest soil quality indicator enzymes, namely, dehydrogenase activity (DHA) and soil fluorescein diacetate (FDA) were found in T6. In T1, 325% and 332.53% more DHA and FDA content was recorded in the aforementioned treatments, respectively. The overall microbial population of bacteria and the actinomycete count (123 and 113 CFU/mL) were higher in the T9 treatment and the fungal population (15.5 CFU/mL) was the highest in the 100% FUSICONT treated plot (T8). In summary, the 100% RDF treatment showed maximum growth and plant yield; however, it was not very effective in improving the soil microbial population and its activity as assessed in the form of DHA and FDA. In conclusion, the co-application of inorganic fertilizers with compatible bio-enhancers should be used for plant growth and yield as well as soil health.