Diversity of Actinomycetes in wheat rhizosphere and plant growth promotion activities

Abstract

In spite of the acknowledged importance of growth-promoting bacteria, only a reduced number of studies were conducted with Actinomycetes on wheat. The objectives of this work were to study the diversity of Actinomycetes associated with the rhizosphere of wheat as a first step in their application in plant growth promotion and biological control. The populations densities of Actinomycetes in wheat rhizosphere and bulk soil and Junagadh were different, with mean values of 1.44±0.1 x 104 and 0.8±0.03 x 103 CFU g-1 of soil for Idar, 1.04±0.89 x 105 and 3.5±0.07 x 104 CFU g-1 of soil for Junagadh, respectively. All isolates isolated and In vitro chitinolytic activity, indol acetic acid production, siderophore production and phosphate solubilization activities were observed in most of the isolates tested. Total 132 isolates were isolated. Of those 132 isolates, 37 isolates were able to solubilize phosphate and 43 isolates show chitinase activity, 20 isolates were able to produce IAA and non of them were able to produced siderophores. Additionally, Actinomycetes from the wheat rhizosphere are genetically diverse and have potential applications as agents of growth promotion.