Is there a secret to grain size? Scientists discover key gene regulating millet yield

Millet is a specialty grain crop originating in my country. It is drought-resistant and barren-resistant. It is an important crop for improving the efficiency of marginal land use in my country and an emerging model plant of the C4 grass family. Grain weight and grain size are important traits of grass crops, which directly affect the final yield of the crop. Discovering major effect loci and key genes that can be used in breeding is of great significance for exploring the genetic basis of high-yield crop breeding.

Recently, the team of the Institute of Crop Sciences of the Chinese Academy of Agricultural Sciences, which is dedicated to the discovery and innovative use of excellent germplasm resources of characteristic crops, discovered the key gene SGD1 for regulating crop grain yield using the millet model system, and analyzed its molecular mechanism for regulating grain development in cereal crops, providing a theoretical basis and genetic resources for increasing the yield of cereal crops. The relevant research results were published in Nature Communications.

Through positional cloning and analysis of millet mutants, the research team found that SGD1 encodes a ubiquitin ligase that can interact with brassinosteroid signaling receptors to enhance the stability of the signaling pathway and thus regulate plant cell size, affecting millet's plant height, grain weight, plant type and other key agronomic traits. The superior haplotype of this gene can significantly increase millet yield per plant and resistance to grain blast, and SGD1 has a conservative function of regulating crop grain yield in cereal crops such as rice, wheat and corn.

Identification and mechanism analysis of the key gene SGD1 regulating millet yield

Yin Weilun, an academician of the Chinese Academy of Engineering, said that the research has greatly promoted the development of millet as a model crop for gene function research and provided an important theoretical basis and new gene resources for improving the yield of gramineous crops. This achievement with important theoretical innovation and agricultural production application value will become a landmark achievement in the field of basic research on millet and gramineous crops.

"For decades, people have made tremendous efforts to discover and study the functions of genes that regulate grain size, but there are still very few excellent genetic resources that can be truly used in variety improvement." Qian Qian, an academician of the Chinese Academy of Sciences, said that this research has brought into play the advantages of the emerging model crop millet both in terms of production application and mechanism analysis, and has built a new platform in the field of basic crop research. It will surely contribute to ensuring national food security in the future.

A researcher at the Institute of Genetics and Developmental Biology, Chinese Academy of Sciences/Chief Scientist of Syngenta China National Innovation Center believes that the discovery of the new millet SGD1 gene resource is another breakthrough in the relevant field, providing an important theoretical basis for improving the yield and stress resistance of millet and other crops, and is also of great significance for agricultural production applications. (Song Yajuan)