Abiotic stresses, such as drought, heat, and salinity, affect negatively fruit development posing severe constraints to plant growth and productivity

The Department of Agriculture National Institute of Food and Agriculture awarded Boyce Thompson Institute for Plant Research Inc. $649,672 on March 1, 2026, under the Agriculture and Food Research Initiative (AFRI) program to identify molecular mechanisms of blossom end rot (BER) resistance in tomato and develop resistant varieties.

The research integrates gene expression and metabolite analysis to characterize stress response in starch-deficient tomato fruit, which exhibits marked resistance to BER—a physiological disorder triggered by drought stress and irregular irrigation that renders fruit unmarketable and causes significant economic losses across tomato, pepper, squash, cucumber, and melon crops. The project will identify genes suitable as targets for breeding strategies to improve fruit resistance to BER and increase tolerance to water stress while maintaining or improving fruit quality, with long-term applications to other stress-induced damage in tomato and potential benefits to U.S. agricultural sustainability.

Performance occurs in Ithaca, New York. The period of performance runs from March 1, 2026, through February 28, 2029. This is a project grant, a form of assistance funding under AFRI's Foundational and Applied Science Program track, which supports competitive, peer-reviewed agricultural research addressing farm bill priority areas in plant health and production.

Cultivated tomato, a valuable vegetable crop, is sensitive to water deficit which limits yield and affects fruit quality. A common effect of drought stress or irregular irrigation in tomato, and other fruit crops (e.g., pepper, squash, cucumber, and melon), is the development of a fruit physiological disorder called blossom end ROT (BER), which results in unmarketable fruitsand important economic losses. Despite its economic importance the molecular mechanisms underlying BER development are not understood, making its prevention very difficult. Currently no cure, other than the use of specific agricultural practices and adequate fertilizer inputs, is available to reduce fruit susceptibility.notably, knowledge of the processes involved in BER resistance is still lacking, which limits the development of resistant tomato varieties. We have observed that tomato fruit with a deficiency in starch synthesisare remarkably resistant to BER, which makes the starch-deficient fruit a unique system to investigate the resistance to this disorder. The main goal of this project is to identify the molecular changes ocurring in the starchless fruit that lead to resistance to BER damage. Our approach will focus on integrating gene expression and metabolite changes to fully characterize the stress response in the starch-deficient fruit and to identify genes that will constitute targets in strategies to improve fruit resistance to BER. Our long-term goal is to generate tomato plants resistant to BER with the potential to withstand other types of stress-induced damage. The development of tomato plants that show an increased tolerance to water stress while maintaining or even improving fruit quality, is of high economic importance and has potential long-range benefits for the sustainability of US agriculture.