Isolation and Characterization of Streptomyces alkaliphilus from Thar Desert Rhizosphere with Plant Growth-Promoting and Antifungal Activities

The Indian Thar Desert presents a harsh environment characterized by extreme conditions such as low moisture in sandy soils, high salinity and elevated soil temperatures, which collectively limit its biodiversity.In the present study, actinobacteria were isolated from the soil of the Bikaner region in the Thar Desert and their potential as plant growth-promoting and antifungal agents was evaluated.A strain identified as Streptomyces alkaliphilus BKA-16 was isolated from the rhizosphere of the native plant Prosopis cineraria and identified through 16S rDNA sequencing.Strain BKA-16 demonstrated notable antifungal activity against Colletotrichum truncatum.Furthermore, it showed the ability to produce phytohormones, including indole acetic acid and ammonia production, and exhibited a clear zone indicating phosphate solubilization.These findings suggest that S. alkaliphilus BKA-16, isolated from the arid Thar Desert, holds promise as a plant growth-promoting bacterium and a biocontrol agent capable of suppressing C. truncatum, the causal organism of anthracnose in green gram, within arid ecosystems of India.