Indole-3-Acetic Acid and its Metabolism in Root Nodules of Pongamia pinnata (L.) PIERRE

Production of indole acetic acid in root nodules and culture by a Rhizobium species from root nodules of the fodder legume Melilotus alba DESR.

“…Indole acetic acid (IAA) was extracted following SINHA and BAN [5] which was a modification of the method specifed for the purpose by different authors [MI. IAA was estimated colorimeeically following GORDON and WEBER [9] using the SALKOWSKI reagent.…”

“…Tryptophan was extracted following NITSCH [ 111 and estimated colorimeeically at 360 nm [lo]. IAA oxidase from the nodules was extracted and estimated following SINHA and BASU [5] after crushing the nodule tissues with 20 ml of cold 0.02 M KHZP04 buffer at pH 5.3. The enzyme was enriched by (NH4)2S04 saturation up to a 95% saturation level and by dialysis.…”

“…The medium was centrifuged and the cell-free supernatant was used for IAA estimation following SINHA and BASU [5], as stated earlier. The extracted IAA was purified by comparing the Rf (0.85) with authentic IAA on thin layer chromatography (TL,C) plates developed with the solvent system isopropano1:ammonia:water (10:1.4:0.6. v/v/v).…”

Pongamia pinnata: A Candidate Tree for Biodiesel Feedstock

“…In a survey, 8.67 nodules per plant along with high biomass were recorded in 1-year-old polybag seedlings of P. pinnata (Srivastava et al, 1999). Sinha and Basu (1981) reported the presence of IAA oxidizing enzymes in the nodules of P. pinnata. A study on nodulation work and nitrogenase activity in relation to nitrogen treatment and seasonal variations in potted P. pinnata seedlings showed that there was a progressive increase in plant growth from May to October in all treatments with no definite pattern per nitrogen treatment (Pokhriyal et al, 1996;Chaukiyal et al, 2000).…”

Studies of the root nodules of leguminous plants IV: Production of indole acetic acid by a bradyrhizobium sp. from the root nodules of a leguminous shrub, crotalaria retusa L

“…To estimate the IAA production, the medium was centrifuged a t 5,OOOg after the incubation time and the cell free supernatant was extracted for IAA according to SINHA and BASU [9] which was estimated colorimetrically according to GORDON and WEBER [lo]. At the beginning, different carbon sources were added separately to the tryptophan supplemented basal medium omitting mannitol.…”