Evaluation of drought tolerance in USDA tomato germplasm at seedling stage

Authors: CHIWINA, KENANI EDWARD - University Of Arkansas; BHATTARAI, GEHENDRA - University Of Arkansas; XIONG, HAIZHENG - University Of Arkansas; JOSHI, NEELENDRA - University Of Arkansas; DICKSON, RYAN - University Of Arkansas; PHIRI, THERESA - University Of Arkansas; ALATAWI, IBTISAM - University Of Arkansas; CHEN, YILIN - University Of Arkansas; Stansell, Zachary; Ling, Kai-Shu; SHI, AINONG - University Of Arkansas

Submitted to: Agronomy
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/13/2024
Publication Date: 2/16/2024
Citation: Chiwina, K., Bhattarai, G., Xiong, H., Joshi, N., Dickson, R.W., Phiri, T.M., Alatawi, I., Chen, Y., Stansell, Z.J., Ling, K., Shi, A. 2024. Evaluation of drought tolerance in USDA tomato germplasm at seedling stage. Agronomy. 14(2), 380. https://doi.org/10.3390/agronomy14020380.
DOI: https://doi.org/10.3390/agronomy14020380

Interpretive Summary: Drought, referred to as deficit irrigation or soil water deficit, has emerged as a pervasive global challenge. The crop and yield losses resulting from drought surpass the cumulative impact of other environmental factors. Tomato is a widely cultivated and consumed horticultural crop, with wild accessions demonstrating significant resilience to drought conditions unlike the cultivated varieties. In the present study, scientists at the U.S. Department of Agriculture (USDA) in Charleston, SC and Geneva, NY collaborated with researchers in the University of Arkansas to evaluate the effects of drought stress on 68 tomato accessions from the USDA plant germplasm collections. Results showed that four accessions PI 365956, PI 584456, PI 390510, and PI 370091, were considered as drought-tolerant. Those drought-tolerant accessions could potentially serve as parental materials in subsequent tomato breeding programs with a focus on enhancing genetic resistance or tolerance to drought stress.

Technical Abstract: Drought, a crucial abiotic stressor, markedly reduces the growth and yield of tomato crops (Solanum lycopersicum L.). Consequently, adopting drought-resistant cultivars and implementing breeding programs to enhance drought tolerance have emerged as enduring solutions to alleviate the adverse effects of drought in various tomato cultivation regions. In this study, 68 tomato accessions from the United States Department of Agriculture (USDA) were assessed in a controlled greenhouse experiment, encompassing both water deficit treatment and a control group subjected to standard watering conditions. The experiment was arranged in a randomized complete block design with three replications. The results of this study pinpointed four accessions PI 365956, PI 584456, PI 390510, and PI 370091, as drought-tolerant accessions. Additionally, high broad-sense heritability was revealed for leaf wilting, leaf rolling, and SPAD chlorophyll content (total leaf chlorophyll). Furthermore, positive correlations were found among parameters associated with leaf wilting, leaf rolling, and SPAD chlorophyll content. The findings of this study provide valuable insights relevant to tomato breeding initiatives, particularly those aimed at fortifying drought tolerance within the elite cultivars of this essential crop.