Abstract:

In order to learn the genetic structure of Phytophthora infestans in Fujian province and provide a theoretical basis for genetic evolution of this pathogen. Sequence related amplified polymorphism (SRAP) analysis was used to detect the genetic variation in populations of Phytophthora infestans in Fujian province. Among 110 combinations of primer pairs screened, 10 primer pairs that amplified consistent polymorphic bands with DNA of 10 isolates were generated. They were further applied to amplify the genomic DNA of 62 isolates collected from different areas and hosts in Fujian province. In total, 92 SRAP markers were obtained. Among the bands, 90 were polymorphic, which accounted for 97.8%. Based on the genetic distance, a dendrogram was constructed with the software NTSYSpc Version2.1. At genetic distance of 0.57, 62 isolates were divided into 4 SRAP groups. There was no correlation between SRAP group and the geographic origin or their hosts. The analysis showed that some strains from one area closely related to that from another area. Nonetheless, rich genetic variation existed among the tested strains in Fujian province.