In this study, we report on the bacterial diversity and their functional properties prevalent in tea garden soils of Assam that have low pH (3.8-5.5). Culture-dependent studies and phospholipid fatty acid analysis revealed a high abundance of Gram-positive bacteria. Further, 70 acid-tolerant bacterial isolates characterized using a polyphasic taxonomy approach could be grouped to the genus Baci...

With the aim of micropropagation of Phyllanthus amarus, an important medicinal herb, shoot tips were cultured in Murashige and Skoog's medium supplemented with kinetin/ BAP singly or in combination with IAA. Growth regulators at lower range (0.1-1.0 mg L(-1)) stimulated direct regeneration of shoots. Kinetin was superior to BAP and kinetin-IAA combination was more suitable than kinetin alone. A...

The rhizosphere is known to harbour a number of bacteria and fungi that can improve plant growth productivity. This study investigated the abilities isolated from guinea corn solubilize phosphate, Idole Acetic Acid (IAA) ammonia production. Purified isolates were confirmed through biochemical test Gram staining. Phosphate solubilization was quantified using Pikovskaya’s, medium on standardized ...

The aim of the present study was to evaluate phytohormone production by symbiotic and saprophytic actinomycetes isolated from the actinorhizal plant Ochetophila trinervis which had previously proved to stimulate nodulation by Frankia. Three saprophytic strains out of 122, isolated from the rhizosphere of this plant with multiple enzymatic activities were selected for plant growth experiments in...

Xanthomonas campestris pv. campestris is the etiological agent of black rot of crucifers, a disease of major economic importance which is a threat to the production of cruciferous crops in many areas of the world [1], During a recent investigation of this patho­ gen for the production of phytotoxic metabolites in liquid culture we observed the biotransformation of certain amino acid constituent...

Background: It is assumed that plant growth regulators produced by beneficial bacterial species could also influence plant growth. IAA is a major plant growth regulator responsible for stimulation of plant growth. There are several microorganisms which are naturally responsible for L- tryptophan metabolism. Methods: In total, 56 indigenous morphologically distinct isolates from rice roots were ...

Plants derive a number of important secondary metabolites from the amino acid tryptophan (Trp), including the growth regulator indole-3-acetic acid (IAA) and defense compounds against pathogens and herbivores. In previous work, we found that a dominant overexpression allele of the Arabidopsis (Arabidopsis thaliana) Myb transcription factor ATR1, atr1D, activates expression of a Trp synthesis ge...

A genome-wide transcriptional profile of Bradyrhizobium japonicum, the nitrogen-fixing endosymbiont of the soybean plant, revealed differential expression of approximately 15% of the genome after a 1 mM treatment with the phytohormone indole-3-acetic acid (IAA). A total of 1,323 genes were differentially expressed (619 up-regulated and 704 down-regulated) at a two-fold cut off with q value ≤ 0....

In this work, we report the detection of aromatic amino acid aminotransferase (AAT) activity from cell-free crude extracts of nine strains of N(2)-fixing bacteria from three genera. Using tyrosine as substrate, AAT activity ranged in specific activity from 0.084 to 0.404 micromol min(-1)mg(-1). When analyzed under non-denaturating PAGE conditions; and using tryptophan, phenylalanine, tyrosine, ...

Rubrivivax benzoatilyticus JA2 and other anoxygenic photosynthetic bacteria produce indole derivatives when exposed to aniline, a xenobiotic compound. Though this phenomenon has been reported previously, the role of aniline in the production of indoles is still a biochemical riddle. The present study aims at understanding the specific role of aniline (as precursor or stimulator) in the producti...