نوع مقاله : مقاله کامل علمی پژوهشی
نویسنده
هیات علمی
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسنده [English]
Abstract:
The phosphate solubilization capability of actinomycetes has recently attracted interest but the mechanism and medium composition effect involved in this process was not clarified. Seven actinomycetes isolates were characterized and evaluated for their plant growth promotion capabilities. The phosphate solubilizing activity, phytate degradation, siderophores, indole acetic acid (IAA) and hydrogen cyanide (HCN) production were investigated. Additionally, all isolates were evaluated as plant growth promoters to maize in pot experiment. The selected isolates were able of solubilizing tri-calcium phosphate (TCP) only when synthetic minimum medium (SMM-agar) was supplemented with ammonium nitrate. Similarly, TCP solubilizing activity in liquid cultures was also observed (from 11 to 216 µgml-1) when medium was supplemented with ammonium nitrate and this behavior was strongly associated with a pH reduction. Phytate degradation, indole acetic acid production (6.26 to 27.81 µg ml-1) and siderophore production (2.47 to 6.01 cm cm-1) was observed to all strains. Significant increase in maize shoot height, fresh weight, dry weight and P uptake (P<0.05) was observed to inoculated plants with respect to uninoculated control. Streptomyces sp. 47 showed the best plant growth promotion performance while plants inoculated with Streptomyces sp. 50 showed a remarkably higher P uptake; both strains were considered good potential inoculants for increasing early maize growth and P uptake.
کلیدواژهها [English]
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