Content of Hormones and Indole Acetic Acid Metabolism in Root Nodules of Tephrosea Purpurea Pers

Root nodules of Tephrosea purpurea Pers. a leguminous medicinal herb, contain high amounts of IAA, gihberellin (GA), cytokinin (CK) and abscisic acid (ABA) like substances. A tryptophan pool present in the nodule may serve as a source of IAA production. Metabolism of IAA in the nodules was evidenced by the presence of IAA metabolising enzymes, IAA oxidase and peroxidase. The symbiont from the nodules, a Rhizobium sp. produced high amount of IAA in culture when supplemented with tryptophan. For IAA production, the bacteria preferred the L-isomer over DL - or D- isomer of tryptophan.