Characterization and establishment of rice endophytic bacteria from Pantnagar

Five true endophytic bacterial isolates were recovered from seed, root, shoot and tissue cultured rice plants of Pant Dhan 6, variety of G.B. Pant University of Agriculture and Technology, Uttaranchal. Presence of eubacterial sequences (an intact band of 1.4 kb) was confirmed by amplification of 16S rDNA in all the isolates. Amplification of nifH sequences (two bands of 800 and 700 bp) was possible in PS1 and PTR2 isolates but active nitrogenase activity was observed in PS1 only, when assayed by gas chromatographic system. All the isolates were siderophore producers. Production of indole acetic acid was reported in three isolates. Isolates PS1 and PTR2 were able to utilize ACC (1-amino cyclopropane 1-carboxylic acid) as a sole carbon source. A varied pattern of enzymes viz., cellulase, pectinase and gelatinase was observed in the recovered isolates. Stable establishment and colonization of inoculated endophytes in rice plants was correlated on the basis of antibiotic resistance and ARDRA profiles of isolated and inoculated endophytes.