山东部分地区棉花黄萎病菌的致病类型及毒性分析

Pathotypes and Virulence Analysis of Verticillium dahliae in Shandong Province

从德州、东营和泰安等棉花黄萎病田采集病株样本,经分离培养和鉴定,共获得Verticillium dahliae Kleb.分离物202株,分别用落叶型和非落叶型菌系特异引物INTD2f/INTD2r和INTND2f/INTND2r对各分离物进行PCR扩增,并随机选择8个菌株分析其产毒素及致萎能力。结果表明,202株分离物中,落叶型菌系201株,非落叶型菌系1株;落叶菌株HDF4-3-1产毒素能力最强,毒素浓度约50.82μg/m L,非落叶菌系HLX5-1-1产毒素能力较弱,毒素浓度约13.85μg/m L;落叶菌系HDF5-3-1的致萎指数最高,为72.5%,非落叶菌系HLX5-1-1的致萎指数最低,为42.5%。表明,落叶型菌系产毒素和致萎能力总体较高。

Verticillium wilt is one of the most destructive diseases of cotton in Shandong Province. The samples of diseased cotton plants were collected from Dezou, Dongying and Taian, and 202 strains of Verticilli- um dahliae Kleb. were isolated and identified. The primers of INTD2f/INTD2r and INTND2f/INTND2r, which were specific for identifying defoliating （D） and non - defoliating （ND） pathotype respectively, were used to amplify the specific segment by PCR. At the same time, 8 strains were randomly selected out to ana- lyze their toxin secretion ability and wilt index. The results showed that 201 strains were identified as D patho- type, and only 1 strain was identified as non - defoliating （ND） pathotype. The D pathotype of strain HDF4 - 3 - 1 showed the highest toxin secretion ability with the content of toxin as 50.82 μg/mL, however, the ND pathotype of strain HLX5 - 1 - 1 had lower toxin secretion ability with the toxin content as only 13.85 μg/mL. The wilt index of D pathotype of strain HDF5 -3 -1 was the highest as 72.5%, while that of ND pathotype of strain HLX5 - 1 - 1 was the lowest as 42.5 %. In a word, D pathotype of strains had higher toxin secretion a- bility and wilt index, overall.