Molecular mechanism of soybean adaptation to short-day high temperature environment cracked

A team led by Professor Nian Hai of the School of Agriculture, South China Agricultural University and Han Tianfu, a researcher at the Institute of crop Science of the Chinese Academy of Agricultural Sciences, announced on the 22nd that important progress has been made in the research on the molecular mechanism of soybean adaptation to short-day high temperature environment. They cloned the soybean puberty gene J, which has been searched for nearly half a century, and revealed the distribution of J in Chinese, American and Brazilian soybean varieties, the results of which were published in the journal Molecular plants.

The tropics have long been considered unsuitable for soybean cultivation. In the 1960s and 1970s, scientists found "long childhood" germplasm resources with delayed flowering under short-day high temperature, longer vegetative growth period and higher dry matter accumulation, and applied to soybean breeding to make soybean expand rapidly in low latitudes. But so far, geneticists and breeders have not been able to identify the specific genes that determine this trait and its mechanism of action.

Han Tianfu and other researchers constructed a recombinant inbred line population with the conventional variety "Zhonghuang 24" and the long childhood variety "Huaxia 3" as parents, constructed a genetic map by RAD-Seq technology, carried out linkage analysis and combined with the whole genome resequencing of the parents, and mapped the long childhood traits to the GmELF3 gene. It was found that the gene was missing a base in "Huaxia 3", which led to the frameshift of the gene sequence and the inactivation of the encoded protein, thus delaying flowering and producing long childhood traits. The transfer of the GmELF3 gene from "Zhonghuang 24", that is, J gene, into "Huaxia 3" can achieve functional complementarity and make the flowering of "Huaxia 3" earlier, which further proves that GmELF3 mutation leads to the emergence of long childhood traits.

It is reported that J gene cloning provides a technical way for the transformation of excellent soybean varieties in middle and high latitudes, and is of great significance for developing soybean production in low latitudes, expanding the planting area of soybean varieties and improving the guarantee capacity of plant protein. (reporter Li he)