The Characteristic Of Different Vegetative Compatibility Groups Of Verticillium Dahliae On Sunflower

Sunflower Verticillium dahliae is generally occurred on the sunflowers as a fungal disease, In China, it occurs in Inner Mongolia. Heilongjiang, Gansu, Jilin and etc. Infected samples were collected from different planting area in China analysisze the characteristic of different vegetative compatibility groups of Verticillium dahliae., Effect of different temperature on pathogen’s growth and the pathogenesis pathogenecity of Verticillium dahliae to different hosts were tested and the ISSR molecular marker technology was used to analysize the genetic diversity of Verticillium dahliae on sunflower in our country.1. After20d’s growing at different temperature, growth rate of different vegetative compatibility groups of Verticillium dahliae in the PDA is not identical also, at15℃～30℃all can grow, and the optimal temperature for growth is25℃, at30℃all strains show slow growth and sparse hyphae. Different groups of Verticillium dahliae at different temperature bacteria raise, VCG1grows fastest and well, VCG2grows slowest.2. Carbendazim concentration in64μg/ml has excellent control effect. Different carbendazim concentrations have different effect on different groups of sunflower Verticillium dahliae. The colonial growth rate has obvious difference; No.7from VCG2shows weak resistance to Carbendazim which has best control effect, EC50is1.549ug/ml; Carbendazim shows worst inhibition effect to No.85from VCG1, its EC50is2.988ug/ml. Carbendazim has less inhibitory effect on VCG1compared with VCG2, VCG3.3. Different group of sunflower Verticillium dahliae have different pathogenicity to different hosts.30strais of sunflower Verticillium dahliae have the strongest pathogenicity on cotton and sunflower, but weakest on chili Among these three groups, VCG1is most virulent to sunflower and also cotton, okra, alfalfa, eggplant, tomato, and pepper. According to disease index, pathogenicity of VCG1is higher than VCG2, VCG3.4. Among100sunflower Verticillium dahliae strains, ISSR analysis results show genetic diversity. Amplification result with four primers (889,842,885and818)are clustering analysized. the genetic similarity coefficient range from0.51～0.97, the data show that strains of different groups have large genetic differences. Most of the strains in one group can be divided into one genetic group of V. dahliae.