Submitted to: Plant Disease
Publication Type: Peer reviewed journal
Publication Acceptance Date: 4/1/2004
Publication Date: 7/1/2004
Citation: Wan, A.M., Zhao, Z.H., Chen, X., He, Z.H., Jin, S.L., Jia, Q.Z., Yao, G., Yang, J.X., Wang, B.T., Li, G.B., Bi, Y.Q., Yuan, Z.Y. 2004. Wheat stripe rust epidemics and virulence of puccinia striiformis f. sp. tritici in china in 2002. Plant Disease. 88(8):896-904. Interpretive Summary: Stripe rust is one of the most important diseases of wheat in China. In the 2001- 2002 growing season, stripe rust epidemic affected about 6.6 million hectares in 11 provinces and autonomous regions. The epidemic was the most severe and widespread since 1990. The wide use of fungicides reduced yield loss to 1.3 million metric tons. The epidemic could be attributed to relatively warm weather from November 2001 to March 2002, high frequencies of highly virulent races, and widely grown susceptible cultivars. Virulences of the rust population were identified using a set of 17 wheat genotypes that have been used to differentiate Chinese races of the pathogen. More than 45 virulence patterns and their frequencies were determined from 926 stripe rust samples collected throughout the disease-occurring regions. Race CYR32, which was virulent on 16 of the 17 Chinese differential genotypes, had the highest frequency and was predominant throughout the epidemic regions. CYR32 also was virulent on many wheat genotypes with reported stripe rust resistance genes. Resistance genes in wheat genotypes Zhong 4, Triticum spelta var. Album, and Moro were still effective against all races identified thus far. Integrated control strategies were recommended to include development and use of cultivars with effective and durable resistance, application of effective fungicides when necessary, and appropriate crop management.
Technical Abstract: In China, wheat stripe rust, caused by Puccinia striiformis Westend. f. sp. tritici Eriks., is one of the most destructive diseases on wheat and can cause sever yield losses when susceptible cultivars are grown and weather conditions are favorable for the disease. Wheat stripe rust most frequently affects the winter wheat growing areas in the Northwest, Southwest, and North China, and the spring wheat growing areas in Northwest China. In the 2001-2002 growing season, stripe rust epidemic of wheat affected about 6.6 million ha in 11 provinces: Sichuan, Chongqing, eastern Gansu, southern and western Shaanxi, southern and central Ningxia, Yunnan, Guizhou, Hubei, Henan, southern and central Hebei, and Shandong. The epidemic was the most severe and widespread since 1990. The wide use of fungicides reduced yield loss to 1.3 million tons nationwide. The epidemic could be attributed to relatively warm weather from November 2001 to March 2002, high frequencies of races CYR31 and CYR32, and widely grown susceptible cultivars. Races CYR31 and CYR32 were virulent on Chinese differential cultivars Trigo Eureka, Fulhard, Lutescens 128, Mentana, Virgilio, Abbondanza, Early Premium, Funo, Danish 1, Fengchan 3, Lovrin13, Shuiyuan 11, Lovrin10, and Hybrid 46. Race CYR32 was also virulent on Jubilejina 2 and Kangyin 655. Race CYR32 was also virulent on wheat genotypes Chinese 166 (Yr1), Heines VII (Yr2, Yr25, and YrHVII), Vilmorin 23 (Yr3a and Yr4a), Heines Kolben (Yr6 and YrHK), Lee (Yr7, Yr22, and Yr23), Clement (Yr9, Yr25, YrCle), VPM1 (Yr17), Selkirk (Yr27), Anza (YrA), Carstens V (YrCV1, YrCV2, and YrCV3), Gaby (YrG), Strubes Dickopf (Yr25), and Suwon 92/ Omar (YrSO). Resistance genes in Triticum spelta album (Yr5), Zhong 4, and Moro (Yr10 and YrMor) were effective against all races identified so far. To control stripe rust in China, we propose an integrated management strategy consisting of developing and growing cultivars with effective and durable resistance, applying effective fungicides when necessary, and using appropriate cultural practices.