Israeli Researchers Successfully Develop Drought-Resistant Tomato Varieties

The research was led by doctorate student Shai Torgeman and professor Dani Zamir from the Hebrew University Robert H Smith Faculty of Agriculture, Food, and Environment and was recently published in the peer-reviewed journal Proceedings of the National Academy of Sciences.

The researchers discovered connections between two areas of the tomato genome that resulted in a 20% to 50% boost in overall output under irrigated and drought circumstances. "The unique structure of the new population, which enables precise mapping of tomato genes, has the potential for extensive application in other plants and could increase productivity," the researchers write.

Tomatoes grown in open fields require pest and fertilizer protection, as well as regular watering. However, the global climate crisis and severe water constraints necessitate the development of new kinds and production methods that ensure adequate returns for farmers.

The researchers crossed two tomato species--a wild tomato from western Peru's deserts and a cultivated tomato--to determine which sections of the genome affect critical agricultural properties like yields.

Individual genomes had no effect on agricultural fertility, but when these genome areas appeared together, they made a considerable contribution to crop fertility even under dry conditions. "Studies of complex traits in plants, such as yield and drought resistance, have relied on significantly smaller populations of 200 or more species," Torgeman explained.

"As a result, identifying all of the interactions (epistasis) between the genes, as well as their influence on important agricultural traits, is impossible. In this study, we genetically crossed two different tomato species and demonstrated that by using a larger population and a genetic map with thousands of markers, we can identify interactions that increase yield," he added.

Over the last four years, Zamir's lab has performed DNA sequencing and intensive data analysis on 1,400 plants. These new tomato varietals are being developed for commercialization by the researchers.

"With global warming, farmers need tomatoes that can cope with changing weather conditions," Torgeman explained. Because global warming causes not only higher temperatures but also extreme weather such as sudden torrential downpours or drought, we need plants with enhanced capabilities. The study was carried out as part of the European Union's "Horizon 2020" scientific cooperation programme.