安徽庐江褐飞虱的抗药性监测及不同杀虫剂对其田间防效评价

近年来,褐飞虱田间种群已对多种药剂产生了抗性,为筛选可防控褐飞虱的高效药剂,2020年-2022年采用稻茎浸渍法连续测定了安徽省庐江县褐飞虱种群对三氟苯嘧啶、呋虫胺、烯啶虫胺、吡蚜酮、氟啶虫胺腈等5种药剂的抗性水平,并在庐江县开展了不同药剂对褐飞虱田间防效试验。室内抗性监测结果表明,2020年-2022年褐飞虱种群对吡蚜酮始终处于高水平抗性(抗性倍数104.6~154.4倍),对呋虫胺的抗性从中等水平上升至高水平(抗性倍数77.7~157.2倍),对氟啶虫胺腈、烯啶虫胺处于中等水平抗性(氟啶虫胺腈抗性倍数21.3~64.5倍、烯啶虫胺抗性倍数14.6~22.6倍),对三氟苯嘧啶处于敏感状态。庐江单季稻试验田田间试验结果表明,在推荐高剂量下,20%三氟苯嘧啶WG、10%异唑虫嘧啶SC等介离子杀虫剂对褐飞虱速效性和持效性表现较好,除了药后1 d 20%三氟苯嘧啶WG防效为74.72%外,2种药剂3~14 d的防效都在80%以上;50%烯啶虫胺SG、22%氟啶虫胺腈SC防效次之,药后1 d防效在67.63%~71.61%,药后3 d至7 d防效有所提高,为77.16%~84.13%,而药后14 d防效降为71.52%~75.77%;50%吡蚜酮WG药后1~7 d防效均在约70%,而药后14 d下降为62.12%;20%氟啶虫酰胺SC、20%呋虫胺WG、10%醚菊酯SC速效性和持效性都表现较差,药后1~14 d防治效果都在80%以下。结合室内抗药性监测和田间防治效果,说明三氟苯嘧啶等介离子类杀虫药剂作为新型杀虫剂品种,可与新烟碱类、吡蚜酮及其混剂交替轮换使用,用于抗药性褐飞虱的治理。

Resistance monitoring and field control efficacy of different insecticides on Nilaparvata lugens in Lujiang county, Anhui province

Brown planthopper, Nilaparvata lugens, has developed resistance to many kinds of insecticides. To screen highly effective insecticides against brown planthopper, resistance of triflumezopyrim, dinotefuran, nitenpyram, pymetrozine, and sulfoxaflor against a field population, which collected from Lujiang county, Anhui province, were monitored by the rice stem dipping method from 2020 to 2022. Meanwhile, field trial was carried out to investigate the efficacy of these insecticides against brown planthopper in Lujiang county. Resistance monitoring test showed that Lujiang populations developed high resistance to pymetrozine (RR:104.6-154.4-fold), moderate to high resistance to dinotefuran (RR:77.7-157.2-fold), moderate resistance to sulfoxaflor and nitenpyram (21.3-64.5-fold and 14.6-22.6-fold, respectively), and still kept susceptible to triflumezopyrim. At the recommended high concentration, triflumezopyrim 20% WG and yizuochongmiding 10% SC showed quick and persistent effects on brown planthoppers, except of a 74.72% control efficacy on the first day after treated with triflumezopyrim 20% WG. The control effect of nitenpyram 50% SG and sulfoxaflor 22% SC was the second, 67.63%-71.61% control efficacy on the first day, and increased to 77.16%-84.13% at the 3rd day to the 7th day after treatment, but reduced to 71.52%-75.77% on the 14th day. The control efficacy of pymetrozine 50% WG was about 70% at the 1st to the 7th day but decreased to 62.12% at the 14th day. For flonicamid 20% SC, dinotefuran 20% WG and etofenprox 10% SC, the control efficacy kept below 80% from the 1st to the 14th day. Combined with the results of resistance monitoring and field trial efficacy, we concluded that the triflumezopyrim and other mesoionic insecticides could be used alternately with neonicotinoids, pymetrozine or their mixtures for the control of resistant brown planthopper.