Pantnagar Journal of Research

Abstract

Trichoderma spp. is widely recognized as promising bioagent for sustainable agriculture due to their multi- dimensional roles in enhancing plant growth, improving soil nutrient availability, and suppressing a wide range of soil-borne phytopathogens. Their ability to solubilize phosphate, produce phytohormones, and secrete hydrolytic enzymes contribute to improved plant health and productivity. Considering the plant growth promoting mechanisms of Trichoderma, eight strains were isolated from rice and guava rhizosphere thriving in Almora and Udham Singh Nagar districts of Uttarakhand. The isolates were assessed in vitro for their phosphate solubilizing potential using TCP (10g/L) amended Mineral Salt medium. During qualitative analysis by plate assay, only 3 isolates showing vigorous growth on TCP amended MSM medium were selected and quantified for phosphate solubilization. The concentration of phosphate mobilized from TCP in culture filtrates was maximum in the culture filtrate of the hilly isolate RAF5 showing 417. 40 µg/mL and RAF6 showing 377.03µg/mL of phosphate after 72h and 96h of incubation respectively. These two potential strains (RAF5 and RAF6) were further investigated for their phosphatase enzyme production, heavy metal tolerance, phytohormone production, siderophore production and hydrolytic enzyme production. The cultures exhibited tolerance towards Cadmium and Lead up to 50ppm concentration. The study reveals a green strategy, using a potential bioagent Trichoderma equipped with both biocontrol and plant growth promoting activities as an alternative to chemical fertilizer, for enhancing plant growth and soil health management in areas contaminated with heavy metals.