Resistance Evaluation Of Rice Cultirars To Xanthomonas Oryzae Pv. Oryzae Race 9 In Northeast China And Testing Of Tale Genes

Bacterial blight(bacterial leaf blight, BLB) as one of the three major diseases on rice production,especially in the Asian region is particularly serious,occurring in our country is very serious,when it occurs will cause a large area of rice cut,a serious threat to the safety of food. The best method for controlling the disease is planting resistant cultirars of rice. As China’s main rice producing areas- the northeast region of the occurrence of bacterial blight shows a sudden and outbreak situation,clearing local rice disease resistance and pathogen virulence diversity is particularly important. With large areas of the northeast super rice cultivation, reducing genetic diversity in rice, accelerating the loss of varietal resistance and further changing in pathogenicity difference of bacterial blight,leading to a lot of trouble for the breeding for disease resistance. Therefore, the analysis of rice bacterial blight resistance in northeast China,learning toxicity characteristics of bacterial blight pathogens in various regions of the three northeastern provinces and the rational distribution of resistant cultirars,as well as the rational distribution of each resistant cultirars, it is of great significance have great significance.In this experiment, with the representative strain JYJ152 for the most toxic race 9, resistance of 255 rice cultirars was tested from the three northeastern provinces.The results shows the resistances of different cultirars of rice to bacterial blight race 9 are differences.There are no high resistant cultirars, they have the resistance(R),the moderate resistance(MR),the moderate susceptibility(MS),susceptibility(S)and the high susceptibility(HS),the main type of resistance is resistance(R)type,and the frequency is 42.4%. This shows that the resources of rice cultirars resistant to bacterial leaf blight are quite rich. We should take advantage of these resistant sources to reduce the occurrence of harmful bacterial blight and improve rice yields in production.Bacterial leaf blight pathogens occur with rice through the type III secretion system secretes effectors, tale genes(transcription activator-like effector) as the main effector are widely distributed in the bacterial blight pathogens. This study detects the northeast rice bacterial blight pathogens tale genes,selects tale gene conservative SphI fragment as a probe, uses Southern blot, preliminary masters tale genes distribution and the advantages tale of bacterial blight pathogens isolated on rice in northeast region. This test analyzes tale genes Southern blot of six rice bacterial blight pathogens. This result shows the hybridizing bands of six bacterial blight pathogen strains are consistent with PX099~A.The tale genes distribution are same. It shows the type and quantity of tale genes of bacterial blight pathogens in northeast region are no difference with PX099~A.