梨和苹果种质对阿太菌果腐病菌的抗性评价及其防治药剂筛选

为明确不同梨和苹果种质对阿太菌果腐病菌Athelia bombacina的抗性以及筛选防治其有效杀菌剂,采用离体菌丝块有伤接种方法对40份梨种质和154份苹果种质进行病斑直径测定,通过聚类分析法和平均病斑直径法对不同种质进行了抗病性分级,并利用菌丝生长速率法测定了13种常用杀菌剂对阿太菌果腐病菌的毒力。结果表明,根据聚类分析法和平均病斑直径法均可将梨和苹果种质划分为高抗、抗、中抗、感和高感5类。与平均病斑直径法相比,梨和苹果种质分别以欧式距离为14和10作为最佳聚类分割点时进行聚类分析能够更加科学地划分类别,从40份梨种质中筛选出金锤子梨1个高抗种质,仅占总数的2.50%,从154份苹果种质中筛选出垂丝海棠、莫斯科透明、新疆苹果、路边石、伏帅等32个高抗种质,占总数的22.73%。药剂试验结果表明,戊唑醇、腈菌唑、咯菌腈和噻呋酰胺对阿太菌果腐病菌菌丝生长的抑制效果较好,抑制中浓度EC_(50)分别为0.027、0.048、0.054和0.095 mg/L。表明梨和苹果种质均可被阿太菌果腐病菌侵染,但不同种质间抗病性差异明显,戊唑醇是采前防治阿太菌果腐病菌菌丝生长的最佳药剂。

Evaluation of resistance to fruit rot pathogen Athelia bombacina for pear and apple germplasms and screening of fungicides

In order to determine the resistance of different pear and apple germplasms to Athelia bombacina and the virulence of different fungicides to Athelia bombacina, 40 pear germplasms and 154 apple germplasms were inoculated in vitro with wounded mycelium, and the diameter of lesions was determined by cluster analysis and average lesion diameter method was used to classify the resistance of different germplasms, and mycelial growth rate method was used to determine the virulence of 13 commonly fungicides to Artemisia fruit rot fungi. The results showed that pear and apple germplasms could be classified into five categories:high resistance, resistance, moderate resistance, susceptibility and high susceptibility by cluster analysis and average lesion diameter method. Compared with the average lesion diameter method, pear and apple germplasms were divided into 14 and 10 European distances as the best clustering points, clustering analysis could classify pear germplasms more scientifically. Among 40 pear germplasms, Jinchuizi was selected as the high resistance germplasm, of which only 2.50% was high resistance, while 154 apple germplasms were screened out. Thirty-two high resistance germplasms, including Chuisihaitang, Mosiketouming, Xinjiangpingguo, Lubianshi, Fushuai and so on, accounted for more than 22.73% of them. Athelia bombacina hyphae were sensitive to triazole fungicides such as tebuconazole, myclobutanil, flusilazole and thifluzamide, the concentration for 50% of maximal effect (EC50) were 0.027, 0.048, 0.054 and 0.095 mg/L, respectively. It was concluded that both pear and apple germplasms could be infected by fruit rot of A. bombacina, but there were obvious differences in resistance among different germplasms, and tebuconazole was the best agent to control the mycelial growth of fruit rot of A. bombacina before harvest.