Microbial Biofertilizers as a Sustainable Alternative to Synthetic Fertilizers in Crop Production

Abstract

The field based experimental design was used to evaluate the effect of using microbial biofertilizers as an alternative to synthetic fertilizers in the production of maize (Zea mays L.). The experiment was designed under randomized complete block design (RCBD) wherein five treatments were laid out, which included unfertilized control, application of microbial biofertilizer in the form of consortium of nitrogen fixing and phosphate solubilizing bacteria and application of microbial biofertilizer in combination with 50% RDF and 75% RDF, both in the form of seed coating and soil application. Plant height, leaves, growth of roots, production of biomass, chlorophyll content, yield components and final grain yield were measured and before and after the experiment soil properties such as available nitrogen, available phosphorus, organic matter and microbial activity were assessed. Analysis of variance (ANOVA) and Tukey's honestly significant difference (HSD) test at 5% significance level were used to analyze data. It was observed that all fertilized treatments significantly improved growth and yield parameters as compared to unfertilized control with the biofertilizer at 75% RDF giving the grain yield similar to 100% RDF recommended dose of synthetic fertilizer and the biofertilizer at 50% RDF gave yield intermediate. The biofertilizer treatments also had significantly higher soil microbial activity, available nitrogen and phosphorus after the experiment than the synthetic-fertilizer-only treatment. The results showed that the application of microbial biofertilizers was able to significantly reduce the use of synthetic fertilizers without affecting the productivity of the crops and also provided extra benefits for the soil health, which facilitated their use in sustainable crop production system.