Azotobacter chroococcum encapsulated Chitosan/PVA composite nanofiber coated seeds for enhancing germination, seedling vigor and growth of green gram (Vigna radiata)

Abstract

Abstract Seed treatment with plant growth promoting rhizobacteria (PGPR) is an idyllic tool for improving germination, growth and productivity of crop. However, the maintenance of viable microorganisms in biofertilizers is a major issue during the seed and soil application. In this work, a superlative methodology was made for encapsulation of Azotobacter chroococcum in Chitosan/Polyvinyl alcohol (PVA) composite nanofiber by electrospin technique and evaluated its effect in improving green gram seed quality. The morphology and functional group of microbes loaded in Chitosan/PVA nanofibers were characterized and confirmed by Scanning Electron Microscope and FT-IR. The results of microbial plating technique showed that nanofiber has maintained the viability of microbes for prolonged time. In addition, Exopolysaccharide and IAA production by Azotobacter chroococcum loaded in nanofiber was estimated and found with constructive outcomes. The bio-efficacy studies exposed that the seeds coated with Azotobacter chroococcum loaded nanofiber, improved the germination percentage, seedling vigor, plant height, plant root length, plant biomass, nodule count and nodules fresh weight. This study concluded that immobilizing PGPR bacteria in nanofiber could improve prolonged shelf-life of microbes and as a potential seed invigoration technique for smart delivery of microbes, and efficient colonization at rhizosphere for better emergence and growth.