Siderophore production by microbial isolates and their effect on nodulation attributes in green gram

Abstract

Many bacteria secrete ferric iron-specific ligands, generically termed siderophore, which aid in sequestering and transport of iron under iron limiting conditions. Eight microbial isolates were tested for their ability to produce siderophores using CAS-agar plate assay, a general test for siderophore detection, which is independent of siderophore structure. Among the isolates Pseudomonas flurescens was noted to 75 per cent siderophore production followed by Azospirillum lipoferum (67 per cent). The siderophore producing microbial isolates significantly enhanced nodulation attributes in green gram compare to absolute control. The ecological advantages in the synthesis of microbial siderophore encourage the use of such microbes as inoculants with root nodule bacteria.