Immobilization of beneficial microbe Methylobacteriumaminovorans in electrospun nanofibre as potential seed coatings for improving germination and growth of groundnut Arachis hypogaea

Abstract Seed inoculation with microbial cells is one of the potential invigouration techniques for enhancing the emergence and growth of plants. Herein, we approached a new localized delivery of beneficial microbial cells (Methylobacterium) by invigorating seeds with electrospun Polyvinyl alcohol (PVA) nanofibre contains microbial cells. Methylobacterium is a growth promoting bacteria recently draws attention in agriculture particularly for drought management. PVA was used in this research because of its electrospinnability and biodegradability. Encapsulation study shows effective immobilization of bacteria cells (Methylorubrum aminovorans) in PVA nanofibre, and SEM and TEM characterization further confirmed the entrapment of microbial cells. The microbial plating enumeration reveals 6.6 x 105 CFU g− 1 of nanofibre to the initial loading population of 1 × 108 CFU. Viability of nanofibre encapsulated bacterial cells under ambient environment found 1.85 × 105 CFU g− 1, 2.2 × 104 CFU g− 1 and 1.2 × 104 CFU g− 1 on 10, 20 and 30 days after storage. In vitro bio-efficacy study exhibits that the seeds coated by PVA nanofibres containing M. aminovorans recorded higher germination, root & shoot length, seedling vigour, drymatter production, plant biomass, plant root volume, nodule numbers and fresh weight of nodules. The data of this study concludes that microbial cells could be immobilized in electrospun nanofibre for extended shelf-life of microbial cells and as effective seed coating for localized delivery.