Isolation and characterization of nitrogen fixing bacteria from raw coir pith

Abstract

Coir fibre is the hard fibre extracted from the coconut husk and coir pith is a lignocellulosic byproduct released during the extraction of coir fibre. The pith is not degraded under normal environmental conditions and accumulates in the fibre extraction units occupying sprawling space in the units. The inherent properties of coir pith make it useful as a plant nutrient. Nitrogen fixing bacteria could be isolated from the coir pith and four strains were amplified with nifH gene viz. NF-4 (Lysinibacillus sp.), NF-7 (Ochrobactrum sp.), NF-12 (Paenibacillus sp.) and an uncultured bacterial clone which shows only 50% similarity to NF-18 (Clostridium sp). The present study targeted the isolation and characterization of natural flora of nitrogen fixing organisms in the coir pith.

Key words: Coir pith, nifH gene, nitrogen fixation, organic manure.