POSTERS: Biological control
Potential of Beneficial Trichoderma isolates in Alleviating Drought Stress in Tomato
Ranjana Rawal - Department of Horticulture and Crop Science, Ohio State University. Maria Soledad Benitez Ponce- Department of Plant Pathology, The Ohio State University, Joseph Scheerens- Department of Department of Plant Pathology, Ohio State University
Tomato (Solanum lycopersicum) is the world’s second most important vegetable crop. Currently, global productivity of tomato is challenged by drought due to inadequate irrigation and erratic rainfall. Research in Trichoderma, a naturally occurring beneficial fungi suggests its role in abiotic stress tolerance. However, the efficacy of colonization and beneficial effects can be isolate specific and depend on plant genotype. The goal of this project is to examine the potentiality of Trichoderma isolates primarily native to Nepal to ameliorate drought stress in tomato. Forty-one Trichoderma isolates, collected from diverse agroecological regions of Nepal, two Ohio isolates and T. harzianum-T22 were selected for this study. An in-vitro assay was undertaken to identify Trichoderma isolates with potential to survive in low moisture environments induced by polyethylene glycol in Potato Dextrose Agar plates. Fourteen isolates were found to be desiccation tolerant and were able to grow up-to -8.5 Mpa. Twenty-four isolates were selected and tested for drought tolerance under greenhouse condition. Four isolates (T16, T31, T33, and T-37) resulted in reduced wilting symptoms under drought and recover faster after irrigation. Plants treated with these isolates had 25-30 % greater shoot biomass compared to control. Isolates collected from drier areas of Nepal were able to promote growth under drought stress as compared to wet areas, indicating a potential adaptation response.