B和Q型烟粉虱种群竞争与抗药性的关系

在室内用棉花植株饲养情况下,对采自浙江杭州的烟粉虱Bemisia tabaci(Gennadius)B型和Q型混合种群的生物型组成以及抗药性水平进行了多代的监测。在室内饲养的F0代,两种生物型比例相当;在F10代,Q型已经完全被B型所取代。与F0代相比,F10代烟粉虱种群对吡虫啉、阿维菌素和氟虫腈的抗性水平明显下降,而对α-氯氰聚酯的抗性保持稳定。该研究表明:在没有杀虫剂选择压力的室内条件下,B型比Q型更具生存优势。然而在烟碱类杀虫剂广泛使用的田间条件下,烟粉虱Q型因比B型对烟碱类杀虫剂具有更强的抗性而获得竞争优势。

Competition between the B and Q biotypes of Bemisia tabaci and its relevance to insecticide resistance

The insecticide resistance of specimens of a mixed population of the B and Q biotypes of Bemisiatabaci （Gennadius） collected in Hangzhou,Zhejiang Province,was monitored for several generations. Whenthe population was reared on cotton without insecticides for 10 generations,the proportion of B-type to Q-type individuals in the F0 population was similar,however the B-type completely replaced the Q-type in theF10 population. Resistance to imidacloprid,abamectin and fipronil in the F10 population was significantly reduced compared with the F0 population,but resistance to α-cypermethrin was similar between the F0 andF10 populations. These results indicate that the B-type is competitively superior to the Q-type in the absence of insecticide selection pressure under laboratory conditions. However,the Q-type is competitively superior infield conditions where neonicotinoids are widely used,presumably because it has greater potential to developres istance to neonicotinoids than the B-type.