Authors
Anmin
Wan
,
Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100094, China
;
Zhonghua
Zhao
,
Division of Crop Disease Control, National Agro-Technique Extension and Service Center, Ministry of Agriculture, Beijing 100026, China
;
Xianming
Chen
,
USDA-ARS, Wheat Genetics, Physiology, Quality, and Disease Research Unit, and Department of Plant Pathology, Washington State University, Pullman 99164-6430, USA
;
Zhonghu
He
,
Beijing Office of CIMMYT, Beijing 100081, China
;
Shelin
Jin
and
Qiuzhen
Jia
,
Gansu Institute of Plant Protection, Lanzhou 730070, China
;
Ge
Yao
and
Jiaxiu
Yang
,
Sichuan Institute of Plant Protection, Chengdu 610066, China
;
Baotong
Wang
and
Gaobao
Li
,
Northwestern University of Agricultural and Forestry Science and Technology, Yangling 712100, China
;
Yunqing
Bi
,
Yunnan Institute of Plant Protection, Yunnan 650200, China
; and
Zongying
Yuan
,
Shanxi Institute of Plant Protection, Taiyuan 030031, China
ABSTRACT
In China, wheat stripe rust, caused by Puccinia striiformis f. sp. tritici, is one of the most destructive diseases of wheat and can cause severe 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 Northwest, Southwest, and North China, and the spring wheat growing areas in Northwest China. In the 2001-2002 growing season, a widespread stripe rust epidemic affected about 6.6 million hectares of wheat in 11 provinces: Si-chuan, Chongqing, eastern Gansu, southern and western Shaanxi, southern and central Ningxia, Yunnan, Guizhou, Hubei, Henan, southern and central Hebei, and Shandong. The epidemic could be attributed to relatively warm weather from November 2001 to March 2002, high frequencies of stripe rust races CYR31 and CYR32, and widely grown susceptible cultivars. Race CYR31 was virulent on the Chinese differential cultivars Trigo Eureka, Fulhard, Lutescens 128, Mentana, Virgilio, Abbondanza, Early Premium, Funo, Danish 1, Fengchan 3, Lovrin 13, Shui-yuan 11, Lovrin 10, and Hybrid 46. Race CYR32 had all the virulence factors of CYR31, plus virulences on Chinese differential cultivars Jubilejina 2 and Kangyin 655, i.e., CYR32 was virulent on all differential cultivars, except Zhong 4. When tested on the world and European differential and some other resistant genotypes, CYR32 was virulent on 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 Dickkopf (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.