A study conducted by Prof. XU Cao's team from the Institute of Genetics and Developmental Biology (IGDB) of the Chinese Academy of Sciences reports a novel breeding strategy to rapidly create climate-smart crops with higher yield under normal conditions and greatly rescue yield losses under heat stress both in staple grain and vegetable crops.
Prof. XU Cao's research team developed a strategy based on climate-responsive optimization of carbon partitioning to sinks (CROCS) by rationally manipulating the expression of cell wall invertase gene (CWIN) genes in fruit and cereal crops. CWIN is the crucial gene that regulates the source-sink relationship in plants. The researchers knocked-in a 10-bp heat-shock element (HSE) into promoters of CWIN genes in elite rice and tomato cultivars, using self-developed high-efficiency, prime-editing tools. HSE insertion endows CWINs with heat-responsive upregulation in both controlled and field environments to enhance carbon partitioning to rice grains and tomato fruits.
Multi-location and multi-season yield tests conducted on tomatoes in greenhouses and open fields showed that the CROCS strategy increased tomato yields by 14% to 47%. Under heat stress, it increased per-plot fruit yield by 26%–33% over controls and rescued 56.4%–100% of fruit yield losses caused by heat stress. In rice cultivars improved by this strategy, a yield increase of 7% to 13% under normal conditions was observed, and a 25% grain yield increase over controls under heat-stress conditions. Specifically, up to 41% of heat-induced grain losses were rescued in rice.
Source: ISAA