Premium
Establishment of Azotobacter on plant roots: chemotactic response, development and analysis of root exudates of cotton ( Gossypium hirsutum L.) and wheat ( Triticum aestivum L.)
Author(s) -
Kumar Rakesh,
Bhatia Ranjana,
Kukreja K.,
Behl Rishi Kumar,
Dudeja Surjit Singh,
Narula Neeru
Publication year - 2007
Publication title -
journal of basic microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.58
H-Index - 54
eISSN - 1521-4028
pISSN - 0233-111X
DOI - 10.1002/jobm.200610285
Subject(s) - biofertilizer , azotobacter chroococcum , azotobacter , rhizosphere , rhizobacteria , exudate , bacteria , biology , amino acid , malic acid , plant physiology , botany , chemistry , citric acid , food science , biochemistry , genetics
Biofertilizers contribute in N 2 fixation, P solubilization, phytohormone production and thus enhance plant growth. Beneficial plant‐microbe interactions and the stability and effectiveness of biofertilizer depend upon the establishment of bacterial strains in the rhizosphere of the plant. This interaction depends upon many factors, one of them being plant exudates. Root exudates are composed of small organic molecules like carbonic acids, amino acids or sugars etc., which are released into the soil and bacteria can be attracted towards these exudates due to chemotaxis. The chemotactic behaviour of Azotobacter strains was studied using cotton (Desi HD 123 and American H 1098) and wheat (WH 711) seedlings and the root exudates of these two plants were chemically characterized. Analysis of the root exudates revealed the presence of sugars and simple polysaccharides (glucose), amino acids (glutamate, lysine) and organic acids (citric acid, succinic acid, maleic acid, malonic acid). Differences between cotton cultivars in root exudates were observed which influenced chemotactic response in Azotobacter . These results indicate colonization with rhizobacteria which implies that optimal symbionts, on the sides of both plant cultivar and bioinoculant bacteria can lead to better plant growth under cultivation conditions. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)