A NEW Chinese scientific study has identified a combination of two crop genes that are in charge of controlling seed dormancy and could be used to reduce the costly phenomenon of pre-harvest sprouting (PHS) in crops such as rice and wheat.

Lead researcher Chu Chengcai said the findings are crucial to avoiding huge agricultural losses and ensuring food security.

Seed dormancy is an important survival tool for plants, allowing them to survive in negative weather conditions. However, excessive dormancy may shorten cultivation time, so many farmers like to plant low-dormancy species of rice and wheat to get a high rate of seed emergence after sowing.

This practice can lead to PHS, a worldwide production problem in which grains germinate on the mother plant before harvest time and often during wet weather, severely reducing grain yield and quality.

Researchers from the Institute of Genetics and Developmental Biology under the Chinese Academy of Sciences have identified two genes, namely SD6 and ICE2, that act in combination to control seed dormancy and have great potential for reducing PHS in rice and wheat.

They found that SD6 and its interaction partner ICE2 can antagonistically control rice seed dormancy by regulating plant hormones.

In the study, when seeds were at room temperature, SD6 was up-regulated to trigger seed germination. However, at low temperatures, SD6 was down-regulated, but ICE2 was up-regulated to keep the seed dormant.

The researchers edited SD6 in three rice species and found that editing the gene could be a rapid and useful strategy for improving PHS tolerance in rice. They then edited the genes in a wheat variety, showing that this provided a similar resistance to PHS. (Xinhua)