打开文本图片集
摘 要：為明确大理州烟草疫霉的群体结构和抗药性水平，采用对峙培养法和含药平板法研究了2013—2014年大理州烟区烟草疫霉的交配型和对甲霜灵敏感性。结果表明，测定的大理州烟区的150个烟草疫霉菌株全部为A2交配型，未发现A1或A0交配型;263个烟草疫霉菌株对甲霜灵的EC50值分布于1.0829～33.6227 mg/L，平均EC50为8.7599±0.0358 mg/L。大理州烟草疫霉菌株对甲霜灵的敏感性差异显著，敏感、中抗和抗性菌株在群体中的比例分别为14.83%、52.85%和32.32%。大理州烟草疫霉在其侵染循环中主要进行无性繁殖，病原菌对甲霜灵的抗药性水平较高，中抗和抗性菌株分布广泛，亟需加快其他新型高效安全替代制剂的筛选和应用。
关键词：烟草黑胫病;烟草疫霉;交配型;甲霜灵敏感性
中图分类号：S435.72 文章编号：1007-5119（2019）06-0049-06 DOI：10.13496/j.issn.1007-5119.2019.06.007
Mating Type and Metalaxyl Sensitivity of Phytophthora nicotianae on Tobacco Black Shank Disease in Dali， Yunnan
CAO Jifen1， HUO Chao1， HU Yanxia2， WANG Xinzhong2， XU Fahua2， ZHAO Zhijian1*
（1. Industrial Crops Research Institute，Yunnan Academy of Agricultural Sciences， Kunming 650205， China; 2. Dali Branch of Yunnan Tobacco Company， Dali， Yunnan 671000， China）
Abstract： In order to investigate population structure and metalaxyl resistance level of Phytophthora nicotianae on tobacco black shank disease， the methods of confrontation culture and fungicide-amended plate were used to determine mating type and sensitivity to metalaxyl of P. nicotianae isolates collected from 2013 to 2014 in Dali， Yunnan Province. The results showed that all 150 isolates of P. nicotianae from 12 counties were A2 mating type and A1 or A0 mating type was not identified. The EC50 values of a total of 263 isolates to metalaxyl distributed between 1.0829 and 33.6227 mg/L， with an average EC50 value of 8.7599±0.0358 mg/L. The ratio of sensitive， moderate resistant and resistant population was 14.83%， 52.85% and 32.32%， respectively， which means that sensitivity to metalaxyl of P. nicotianae isolates collected from Dali had significant differences. Our results suggest that the population structure of P. nicotianae was mainly maintained through asexual propagation in its life cycle in Dali. The pathogen had a high resistance level to metalaxyl and both moderate and resistant isolates were widely distributed. It is urgent to screen and make use of new high-efficiency and safe alternatives for black shank disease management.
Keywords： tobacco black shank disease; Phytophthora nicotianae; mating type; metalaxyl sensitivity