Soybean domestication was originated in China and introduced to various parts of the world. Soybean provides plant oil and protein to human and is significant grain and economic crops worldwide. As population increases and dietary structure changes, demands have been increasing year by year. Further increasing yield per unit area and improving quality is important to safeguard world soybean production.
Wild soybeans are small, low in oil and high in protein. Domestication produces bigger soybeans with higher oil and lower protein content. In the process of soybean domestication and improving, it’s not clear whether single-gene can complete simultaneous regulation and control of yield and quality previously.
Prof. Shou Huixia from the College of Life Sciences had been searching for key genes that influence seed development using top soybean technology system and research platform in our country and discovered discover GmSWEET10a/b (gene with specific expression) first. Meanwhile, the research team led by Tian Zhixi from Institute of Genetics and Developmental Biology, CAS conducted whole genome sequencing and character evaluation for over 870 soybean samples. After comparison, researchers from both sides discovered that GmSWEET10a/b is the most efficient gene in yield increasing and quality improvement ever discovered.
Further research revealed that GmSWEET10a/b express itself in the parenchymatous tissue of seed coat and mediate sucrose, glucose and fructose from seed coat to embryo. Knocking GmSWWEET10a/b will decrease hundred-grain weight and oil content and increase protein content. If two genes are both knocked out, hundred-grain weight will decrease by 40.2%, oil content by 40.7% but increase protein content by 32.1%. If two genes are overexpressed, hundred-grain weight and oil content will increase significantly, and yield for single plant will increase by 11-20%. The study is important to increase soybean yield and quality through molecular breeding, introduced Prof. Shou Huixia, the research results can be directly used for next generation breeding, soybean quality screening and crossbreeding assisted by molecular markers, thus having positive meaning for yield increasing and quality improvement.
The study discovered that GmSWEET10a/b can simultaneously regulate seed size, oil content and protein content and plays a key role in soybean domestication and improvement. The research result has been published in National Science Review titled Simultaneous changes in seed size, oil content, and protein content driven by selection of SWEET homologues during soybean domestication by the research teams led by Shou Huixia from ZJU, Tian Zhixi from Institute of Genetics and Developmental Biology, CAS, Guan Yuefeng from Fujian Agriculture and Forestry University and Chen Liqing from University of Illinois.
Link of the paper：https://doi.org/10.1093/nsr/nwaa110
Domestication Process of GmSWEET10a/b
(Compiled based on Qiushi Newsroom)