Tomato triumph: Unraveling the genetic loss of saline-alkaline tolerance

A pivotal study has identified a natural genetic variation in the promoter of the tomato gene SlSCaBP8 that has resulted in reduced saline-alkaline tolerance in modern tomato cultivars. This discovery is key to understanding the genetic basis of stress response and could guide future breeding programs to enhance crop resilience against soil salinization.

Saline-alkaline stress significantly impacts crop yield and quality worldwide, posing a greater threat than neutral salt stress due to its combination of high pH and ion toxicity. Over 950 million hectares of soil are affected, leading to substantial agricultural challenges. Researchers are exploring genetic mechanisms that enable crops to withstand saline-alkaline conditions. Understanding these mechanisms is crucial for developing resilient crop varieties that maintain productivity and quality under adverse environmental conditions.

A team from Shandong Agricultural University, in collaboration with Beijing University of Agriculture, published their findings (DOI: 10.1093/hr/uhae055) on February 23, 2024, in the journal Horticulture Research. The study explores the genetic mechanisms underlying the loss of saline-alkaline tolerance in tomatoes, focusing on the SlSCaBP8 gene. Researchers discovered that variations in this gene's promoter region significantly impact the plant's stress response.

The study revealed that the SlSCaBP8 gene, an EF-hand Ca²⁺ binding protein, plays a critical role in regulating saline-alkaline tolerance in tomatoes. Through genetic and biochemical analysis, the researchers found that a specific natural variation in the promoter of SlSCaBP8 contributed to the loss of tolerance observed in domesticated tomato varieties compared to their wild counterparts. The introgression line Pi-75, which contains the SlSCaBP8 gene from wild tomato, showed enhanced tolerance to saline-alkaline conditions. This was linked to higher expression levels of SlSCaBP8 under stress. The research provides crucial insights into the genetic basis of stress tolerance, highlighting the importance of the SOS pathway in managing ion homeostasis in plants.

Dr. Qian Chen, one of the corresponding authors, stated, "Our findings underscore the importance of understanding genetic variations that occur during crop domestication. By identifying the key promoters affecting stress tolerance, we can develop more resilient crop varieties, ensuring better yield and quality even under adverse conditions."

This study opens new avenues for breeding salt-tolerant tomato varieties. By leveraging the natural variations in the SlSCaBP8 promoter, breeders can enhance the saline-alkaline tolerance of commercial tomato varieties, potentially improving crop performance in salt-affected soils worldwide. This advancement not only benefits tomato cultivation but also sets a precedent for improving other crops facing similar stress challenges.

###

References

DOI

10.1093/hr/uhae055

Original Source URL

https://doi.org/10.1093/hr/uhae055

Funding information

This work was supported by the National Natural Science Foundation of China-Shandong Joint Fund (Grant U22A20459 to C.L. and Q.C.), the National Natural Science Foundation of China (32272701 to Q.C., 32000364 to X.M.), the Agricultural Seed Project of Shandong Province (2020LZGC005 and 2021LZGC017 to C.L. and Q.C.), and the Tai-shan Scholar Program from the Shandong Provincial Government (tsqn20161021 to Q.C. and tsxk20150901 to C.L.).

About Horticulture Research

Horticulture Research is an open access journal of Nanjing Agricultural University and ranked number one in the Horticulture category of the Journal Citation Reports ™ from Clarivate, 2022. The journal is committed to publishing original research articles, reviews, perspectives, comments, correspondence articles and letters to the editor related to all major horticultural plants and disciplines, including biotechnology, breeding, cellular and molecular biology, evolution, genetics, inter-species interactions, physiology, and the origination and domestication of crops.