Resistance to the Carboxylic Acid Amide (CAA) Fungicides in Phytophthora capsici
Phytophthora capsici, a heterothallic oomycete pathogen, causes destructive diseases on many vegetable crops all over the world. Carboxylic acid amide fungicides (CAAs) , such as flumorph, dimethomorph, iprovalicarb and mandipropamid, exhibit a high level of activity against members of the Peronosporaceae and the genus Phytophthora but not Pythium. In this study, sequences of four cellulose synthase (CesA) genes were analyzed between sensitive and resistant isolates of P. capsici obtained by spontaneous mutation from sexual progeny. Only two Amino acid changes in CesA3 were found to be linked with CAA-resistance. According to mutation locus, all resistant isolates were divided into two types. One carried mutation at codon 1105 with Gly to Ala, and another carried mutations G1105A accompanied with V1109L. Mutants with only one mutation exhibited lower resistant level to flumorph and dimethomorph than those with two mutations. These mutations located on the transmembrane domain near the Cterminal of CesA3.
CAA fungicides Phytophthora capsici resistance mechanism gentic mechanism
Lei Chen Xiaohong Lu Qian Wang Xili Liu
Department of Plant Pathology, China Agricultural University, Beijing, China
国际会议
北京
英文
444
2012-09-15（万方平台首次上网日期，不代表论文的发表时间）