Sensitivity and resistance monitoring of Colletotrichum panacicola to difenocon-azole and tebuconazole in Northeast China
In this study,the sensitivity of Colletotrichum panacicola to difenoconazole and tebuconazole was determined with 109 isolates collected from the main ginseng-growing regions in Jilin,Liaoning and Heilongjiang provinces by measuring mycelial growth rate in vitro.Meanwhile,the resistance level of 435 C.panacicola isolates from 15 villages and towns in Jilin and Liaoning provinces was evaluated via the minimum concentration inhibition method.The result showed that the sensitivity frequency of the 109 isolates of C.panaci-cala to difenoconazole and tebuconazole presented a normal distribution,with the average EC50 values of 0.4044±0.1996 μg·mL-1and 0.1717±0.0045 μg·mL-1,respectively,which could be adopted as the relative susceptible baselines of C.panacicola to these two fungicides.Moreover,C.panacicola strains from different regions displayed no significant difference in the sensitivity to difenoconazole and tebuconazole.Spearman correlation analysis of log10EC50 values of the 109 isolates of C.panacicola showed no cross resistance between the two fungicides.Here,only one strain of C.panacicola showed low resistance to difenoconazole,with a resistance frequency of 0.22％;no tebuconazole-resistant isolate was detected.In conclusion,the C.panacicala populations from Northeast China exhibited high sensitivity to difenoconazole and tebuconazole,indicating that the two fungicides can still be used for the control of anthracnose of ginseng.The results lay a basis for the assessment of resistance risk of C.panacicala to fungicides and also for the rational application of fungicides in the chemical control of ginseng anthracnose in Northeast China.
NETL
NSTL
万方数据
