Significance of secondary metabolites elicited by Zhihengliuella sp. ISTPL4 in plant growth promotion under arsenic stress.

Bacterial secondary metabolites have an important role in encouraging the growth of plants by influencing phytohormone production and metabolism. The effect of secondary metabolites secreted by an actinobacterium Zhihengliuella sp. ISTPL4 (Z. sp. ISTPL4) on growth promotion in the Oryza sativa plant was studied. The growth of Z. sp. ISTPL4 has been evaluated in the presence of Arsenic (As) up to the concentration range of 0.2–1.9 mM followed by observing the growth of rice in the presence of As. The present study was carried out to analyze the significant role of metabolites released by Z. sp. ISTPL4 in growth-promoting activities of plants. We have also reported various metabolites released by Oryza sativa after microbial inoculation under normal growth conditions and in the presence of As stress. It was observed that 43 metabolites were released by Z. sp. ISTPL4 under normal conditions and 34 metabolites were released in the presence of As stress. Some of these metabolites including Hexadecane, Heptadecane, Hexadecanoic acid methyl ester, Eicosane, Cyclo (L-prolyl-L-valine) were common among metabolites released by Z. sp. ISTPL4 in the presence of normal growth conditions and under As stress. The area percentage of hexadecenoic acid methyl ester, methyl stearate, octadecanoic acid, 2,3-dihydroxypropyl ester was higher in the presence of As stress than its concentration under normal growth conditions while hexadecane is released in the presence of As stress only. These metabolites are involved in antimicrobial, antiproliferative antioxidants and plant growth promotion by stimulating gibberellin synthesis. The results of our research indicate that under different biotic and abiotic stress conditions, the actinobacterium Z. sp. ISTPL4 can be deployed to improve sustainable agricultural practices. [Display omitted] • Zhihengliuella sp. ISTPL4 tolerate up to 2 mM concentration of arsenate. • Secondary metabolite production in Zhihengliuella sp. ISTPL4. • Abiotic stress-mediated secondary metabolite production in rice. [ABSTRACT FROM AUTHOR]