Vol. 1, Issue 1, Part A (2019)

Salinity stress is an important environmental problem that adversely affects crop production by reducing plant growth. The impact of rhizobacterial strains to alleviate salinity stress on the germination of Arachis hypogea seeds were assessed using different concentrations of NaCl. Plant growth hormones, also known as phytohormones, regulate plant development and evoke a specific physiological response in plants, at very low concentration. Indole acetic acid (IAA) is one of the most important physiologically active auxins.IAA is a general product of L-Tryptone metabolism produced by many microbes including Plant Growth Promoting Rhizobacteria (PGPR). Tryptophan is an essential amino acid that can undergo oxidation by the action of the bacterial enzyme tryptophanase. Not all bacteria possess this enzyme and so this test can be used as a biochemical differentiators this tryptophanase is mainly use in production of plant growth hormones using rhizobacteria. The most important effect of indole acetic acid is to promote development of roots and stems, through stretching of the newly formed cells in the meristem. Effect of IAA producing Rhizobium, sp and Serratia, sp bacteria on plant growth was studied by pot culture experiments by using sterilized air dried soil and viable ground nut seed. Both bacteria demonstrated increase in root length, shoot length, root and shoot fresh and dry weight, on bacterial inoculated ground nut seeds over control. The main goal of this study is to isolate and screen indigenous Indole acetic acid-producing bacteria from different rhizospheric soil.