A total of 210 locally actinomycetes isolates were screened for their potential to produce IAA and 138 (65.7%) isolates were able to utilize tryptophane and produce the IAA. The 12 isolates with high IAA production were secondary screened to select the most highest producer. It is worth mentioning that the most highest IAA producing isolate (22 µg/ml of IAA) was Streptomyces sp. ASU14 recovered from rhizospheric soil sample after wheat cultivation in New valley governorate in Egypt. TLC and HPLC analysis confirmed the IAA production in the cell filtrates of the strain. Sequencing of 16S rRNA genes of the Streptomyces sp. ASU14 isolate had 16S rRNA gene with 99% nucleotides identity to that of Streptomyces atrovirens NRRLB16357 available in Genbank database. The nucleotide sequences of the isolate Streptomyces atrovirens ASU14 was deposited in the GenBank nucleotide sequence database under accession number KC145267. IAA production by Streptomyces atrovirens ASU14 was optimized by studying some factors and the results revealed that the maximum IAA value was obtained when the isolate cultivated in tryptone yeast extract broth medium supplemented by tryptophane 5 mg/ml, adjusted at pH 6 and incubated at 30°C for 13 days. These results suggest that IAA-producing Streptomyces atrovirens ASU14 could be a promising candidate for utilization in growth improvement of plants of economic and agricultural value.
Research Abstract
Research Department
Research Journal
Biology and eart sciences
Research Member
Research Publisher
.tmkarpinski
Research Rank
1
Research Vol
3 (2)
Research Website
http://www.journals.tmkarpinski.com/index.php/jbes/article/view/76
Research Year
2013