[Objective] This study aimed to investigate the resistance to different fungicides in Phytophthora parasitica var. nicotianae. [Method] Under indoor incubation conditions, the resistance to dimethomorph, metalaxyl-man...[Objective] This study aimed to investigate the resistance to different fungicides in Phytophthora parasitica var. nicotianae. [Method] Under indoor incubation conditions, the resistance to dimethomorph, metalaxyl-mancozeb, propamocarb and ovraclostrobin.dimethomorph in P. parasitica strain isolated from Zhenyuan County in Qiandongnan State was analyzed with colony growth measurement method. [Result] P. parasitica exhibited different levels of sensitivity to four fungicides. To be specific, P. parasitica exhibited the highest resistance to dimethomorph, and ECho reached 1.19 μg/ml. [Conclusion] In Zhenyuan tobacco-growing area, long-term single use of dimethomorph possesses certain resistance risk in prevention and control of black shank disease.展开更多
Total 69 isolates of Phytophthora nicotianae var. nicotianae were isolated and identified from tobacco black shank samples collected from different areas of Anhui province,and mating types of the oomycete were investi...Total 69 isolates of Phytophthora nicotianae var. nicotianae were isolated and identified from tobacco black shank samples collected from different areas of Anhui province,and mating types of the oomycete were investigated by the method of partnership culture in vitro on L-tryptophan medium with β-sitosterol.The results showed that A2 mating type was the predominant in isolates of P.nicotianae var.nicotianae,next was A0 mating type,A1 and other mating types were not observed.It was suggested that sexual reproduction of P.nicotianae var.nicotianae might not take place frequently,and Anhui province might not be the original center of P.nicotianae var.nicotianae.The results indicated further that mating type geographical distribution of P.nicotianae var.nicotianae in Anhui province was in line with that in China.In addition,the significance of the test results and the possible reason for A1 mating type being absent were discussed.展开更多
文摘[Objective] This study aimed to investigate the resistance to different fungicides in Phytophthora parasitica var. nicotianae. [Method] Under indoor incubation conditions, the resistance to dimethomorph, metalaxyl-mancozeb, propamocarb and ovraclostrobin.dimethomorph in P. parasitica strain isolated from Zhenyuan County in Qiandongnan State was analyzed with colony growth measurement method. [Result] P. parasitica exhibited different levels of sensitivity to four fungicides. To be specific, P. parasitica exhibited the highest resistance to dimethomorph, and ECho reached 1.19 μg/ml. [Conclusion] In Zhenyuan tobacco-growing area, long-term single use of dimethomorph possesses certain resistance risk in prevention and control of black shank disease.
文摘Total 69 isolates of Phytophthora nicotianae var. nicotianae were isolated and identified from tobacco black shank samples collected from different areas of Anhui province,and mating types of the oomycete were investigated by the method of partnership culture in vitro on L-tryptophan medium with β-sitosterol.The results showed that A2 mating type was the predominant in isolates of P.nicotianae var.nicotianae,next was A0 mating type,A1 and other mating types were not observed.It was suggested that sexual reproduction of P.nicotianae var.nicotianae might not take place frequently,and Anhui province might not be the original center of P.nicotianae var.nicotianae.The results indicated further that mating type geographical distribution of P.nicotianae var.nicotianae in Anhui province was in line with that in China.In addition,the significance of the test results and the possible reason for A1 mating type being absent were discussed.
