Effect of fungal biocontrol agents on enhancement of drought stress tolerance in rice (Oryza sativa L.)

Rice is the staple food crop for about half of the population of the world. Drought is a major stress limiting factor of this crop. In the recent years, biocontrol agents like Trichoderma spp. have become popular as plant growth promoter and shown to enhance drought tolerance in plants. Therefore, present investigation investigation was undertaken to evaluate the different biocontrol agents i.e. Trichoderma harzinum 1, Trichoderma harzianum 2, Chaetomium globosum and Talaromyces flavus against the drought in resistant (DRR 42 and Sahbhagi Dhan) and susceptible (IR 64) varieties of rice. Prior to sowing seeds were bioprimed separately with each isolates of Trichoderma harzianum @ 10g/kg and were sown in pots. Drought treatment of 4 days, 7 days, 10 days and 13 days were given as per the standard protocol. Biocontrol agent Trichoderma harzianum (T2) was observed most effective for drought tolerance followed by Chaetomium globosum. After 13 days of drought treatment minimum wilting (20%) was observed in Sahbhagi Dhan treated with Trichoderma harzianum 2. Four and 10 days drought stressed plants were subjected to different biochemical analysis. Significantly positive correlation (r = 0.91) was observed between wilting and Malondialdehyde (MDA) content. While negative correlation (r = −0.67) was observed between wilting and average plant weight. Study suggested that Trichoderma harzianum 2 treatment during drought stress in rice plants can delay the drought upto 3-5 days