Utilization of different carbon substrates by native pink pigmented facultative methylotrophs isolated from direct seeded rice

Abstract

Investigations were carried to study the pink pigmented facultative methylotrophs and their beneficial effects on direct seeded rice. Samples of phyllosphere leaves and rhizosphere soil were collected from major DSR growing districts of Hyderabad-Karnataka; about fifty isolates were isolated on selective AMS medium. Further the isolates were characterized based on their morphological and biochemical characteristics, based on the observed characteristics, the isolates obtained belong to the genus Methylobacterium. There after, all the isolates carried out for carbon source utilization for the purpose of tentatively identification of PPFM isolates. The twenty isolates selected on the bases of pigmentation were tested for the utilization of the different carbon compounds for the purpose of tentatively identification of PPFM isolates. The obtained results based on carbon source utilization all the isolates could be classified as follows: PPFM-8, PPFM-31, PPFM-32 Methylobacterium phyllosphaerae, PPFM-1, PPFM-5, PPFM-18 and PPFM-42 M. oryzae PPFM-3, PPFM-15, PPFM-16, PPFM-19 and PPFM-44 M. mesophilicum, PPFM-28, PPFM-29 and reference strain M. extorquens, PPFM-4, PPFM-17, PPFM-22, PPFM-30, PPFM-43 and PPFM-47 Methylobacterium sp.