Soybeans are photoperiod sensitive short day crops. The growth period and yield of soybeans are influenced by changes in the photoperiod. Seed weight is one of the key traits that determine soybean yield, but the key genes that control soybean seed weight and their mechanisms of photoperiodic effects are still unclear.

Hou Xingliang, the research group of Agriculture and Biotechnology Research Center of South China Botanical Garden, Chinese Academy of Sciences, used the soybean recombinant inbred line population to identify the key gene Dt1 that controls seed weight by map based cloning. Further research has found that under long day conditions, Dt1 is highly expressed during seed development. Its protein interacts with the sucrose transporter GmSWEET10a, negatively regulating the input of sucrose from the seed coat to the embryo, thereby regulating seed development. However, under short day light cycle conditions, the transcription level of Dt1 is lower and does not participate in seed development regulation. In addition, the study discovered a new natural allele (H4 haplotype) of Dt1. This haplotype can decouple its pleiotropic effects on seed size and growth habits, maintaining its function in seed development regulation without affecting soybean stem growth habits. This achievement provides new insights into the response of soybean seed development to photoperiod at different latitudes, and provides new genetic resources for improving soybean yield by controlling seed weight and growth habits.

This study further reveals the function of the photoperiod in regulating soybean seed development through Dt1 mediated sucrose transport. The relevant research results are published online in Molecular Plant. This work was completed in collaboration between South China Botanical Garden and Guangzhou University. The research work was supported by the major projects of the National Natural Science Foundation of China, the national key research and development plan and the strategic leading science and technology project of the Chinese Academy of Sciences.

Paper link:论文链接



A Model of Dt1 Regulating Photoperiod Dependent Soybean Seed Weight/Size