Seed Biopriming with Trichoderma Harzianum for Growth Promotion and Drought Tolerance in Rice (Oryza sativus)

Water scarcity is one of the primary consequences of climate change, which negatively affects crop growth and productivity. Current research focuses on the effect of an antagonistic fungus, Trichoderma harzianum, on drought stress management in rice. Of 30 Trichoderma isolates examined, only seven isolates, namely IRRI 1, TH 28, TH 21, TH 30, TH 3, TH 26, and TH 7 were selected as drought tolerant due to their ability to colonize well on de-oiled cake of Neem at low moisture content of 10 to 20 percent. These isolates were used as seed biopriming to test their ability to improve drought tolerance in tillering stage of rice. T. harzianum strains IRRI-1, TH-28, TH-30, and TH-21 showed the greatest reduction in leaf rolling after six, nine, and twelve days of drought exposure. These most potent strains, IRRI-1, TH-28, TH-30, and TH-21, were also able to improve drought tolerance in rice plants by minimizing proline content and increasing the leaf total chlorophyll content, leaf area index, relative water content, and Membrane Stability Index. Thus, it was found that Trichoderma harzianum strains IRRI-1, TH-28, TH-30 and TH-21 are very effective in providing drought tolerance in rice plants by interfering with the morphological, physiological and biochemical activities of rice plants. Colonization of rice seeds by drought-tolerant Trichoderma harzianum strains increased growth and delayed drought response in rice, which could be very critical and helpful in rice crop production, especially under drought conditions.