Chinese scientists have successfully cloned the gene of "ksing" of rice white leaf disease

, Beijing, January 13 (Xinhua Huang Wei) Recently, Chinese scientists successfully cloned the rice white leaf disease "kexing" - long-lasting disease-resistant gene Xa7. By revealing the new disease-resistant molecular mechanism of Xa7's high resistance, broad spectrum, long-lasting and heat-resistant properties, the foundation is laid for the long-term prevention and control of rice white leaf disease.
white leaf disease is one of the "three major diseases" in rice production in China, which seriously affects the yield and quality of rice. Data show that before the 1980s, white leaf disease often led to rice production reduction of 20% to 30%, in severe cases up to 50%, or even the end of harvest.
according to Zhou Jianmin, a researcher at the China
Institute of Genetics and Developmental Biology, white leaf disease has been effectively controlled due to the introduction of resistant genes such as Xa4, Xa21 and Xa23 in China's main rice varieties. However, with the global warming, white leaf disease bacteria continue to mutate, a new type of pathogenic variants have emerged, resulting in the main rice varieties gradually lose disease resistance.
years, rice white leaf disease is increasing year by year, the problem of 'new diseases' is becoming more and more serious, and the loss of yield is huge. Zhou Jianmin said.
, Xa7 has long been the internationally recognized "star gene" that is most resistant to white leaf disease bacteria, 20 years after its enduring resistance was first discovered. However, due to the fact that the sequence of the disease-resistant genetic point is completely different from the reference genome, many laboratories in the world have not been successful in the identification of the Xa7 gene.
Zhejiang Normal University Ma Bojun team and China Rice Research Institute Qian Qian qian before the
team jointly attacked, recently made a breakthrough - on the basis of fine positioning, through radiation mutation and genetic screening, finally locked Xa7 in the 28kb range, and through a large number of molecular function verification, successful cloning of Xa7 gene.
, the study also showed that at high temperatures, Xa7 was induced to produce a defensive response to prevent the invasion of germs more prominent. In the context of global warming, the gene has greater breeding value.
, the study has been published in the journal Plant Communications.