【目的】了解不同种植模式的小菜蛾Plutella xylostella(L.)田间种群对氟啶脲(Chlorfluazuron)的抗性动态,旨在为该药剂的田间抗性管理提供参考。【方法】参照中华人民共和国农业行业标准"十字花科蔬菜小菜蛾抗性监测技术规程"(NY/T 2360-2013)进行。【结果】与敏感种群相比,不同监测点小菜蛾种群由于地理位置、种植模式、用药习惯等的不同,对氟啶脲的抗性表现出地区差异和年度间差异。小户型连年种植模式的广东广州地区小菜蛾田间种群对该药剂抗性相对最高,以中等及以上抗性水平为主,最高抗性比(RR值)为437.58;而规模化连年种植模式的广东惠州地区小菜蛾种群对该药剂的抗性仅次于广东广州地区,也以中等及以上抗性水平为主,最高RR值为337.18;小户型连年种植为主的连州地区小菜蛾种群对氟啶脲的抗性动态与广东惠州地区的非常相似,抗性水平比广东广州地区和广东惠州地区稍轻;山区小户型多样化种植模式的广西柳州地区小菜蛾田间种群对该药剂的抗性相对最低,以低水平抗性为主,最高RR值仅为23.24。但4个抗性监测点也存在抗性发展大趋势基本一致的共同点。具体表现在4个监测点小菜蛾种群对该药剂的抗性在2008年均为中等以上抗性水平,随后通过调整了用药策略,多数地区2009—2011年抗性下降至低水平(RR值小于10)。2012年随着田间防治压力的上升,氟啶脲用药量和用药频次再次增加,造成多数地区抗性再次上升至中等及以上水平,并持续到2014年。【结论】小菜蛾对氟啶脲的抗性田间稳定性不高,停用或过度依赖该药剂一段时间,抗性即出现下降或上升,基本与用药情况、频次和强度等呈正相关。
[Objectives] To investigate the development of resistance to chlorfluazuron in the diamondback moth(DBM), Plutella xylostella(L.), in fields with different cropping patterns, and thereby provide information useful for managing the development of resistance to this insecticide. [Methods] Data were obtained during the agricultural industry standard of the People's Republic of China's "Crucideline monitoring program for insecticide resistance in P. ylostella on cruciferous vegetables"(NY/T 2360-2013). [Results] Compared to a DBM sensitive strain, resistant strains from four monitoring stations differed in their resistance to chlorfluazuron due to differences in geographical locations, vegetable cropping patterns, and methods of insecticide use. On the whole, the resistant strain from Guangzhou, Guangdong, where there was a small-scale, year by year, planting model, was the most resistant, with moderate, or high-moderate resistance to chlorfluazuron being the norm(maximum RR value = 437.58). The next most resistant strain was that from Huizhou, Guangdong, where there was a scale-successive cropping pattern, in which moderate, or high-moderate, resistance to chlorfluazuron was typical(maximum RR value = 337.18). Resistance of the Lianzhou, Guangxi strain was similar to that of the Guangzhou and Huizhou strains, but was slightly less than that of these strains. This strain had the lowest resistance to chlorfluazuron(maximum RR value = 23.24), due to the small scale of the planting model in the mountainous region inhabited by this strain. Resistance data from the four monitoring stations showed a similar trend. In 2008, resistance at most monitoring stations was moderate, or high-moderate, then decreased in 2009-2011 after the use of chlorfluazuron was discontinued. However, in 2012, chlorfluazuron was once again used to control DBM at the four monitoring stations with the not unexpected result that resistance once again increased. [Conclusion] The resistance of DBM to chlorfluazuron is u