V Joseph Shimat
Department of Entomology, University of Georgia, UGA Griffin Campus, 1109 Experiment Street, Griffin, GA 30223, USA.
Insects. 2020 Apr 1;11(4):216. doi: 10.3390/insects11040216.
Azaleas ( L. spp.) are widely grown ornamental plants in eastern and western regions of the USA. The azalea lace bug, (Scott) (Hemiptera: Tingidae), is an important insect pest of azaleas. Adults and nymphs of consume chlorophyll in azalea foliage, and severely affected plants appear bleached. Neonicotinoid insecticides are effective and widely used for control; however, nursery growers and landscape professionals are concerned about nontarget effects on beneficial insects and demand neonicotinoid-free plants. There is clearly a need to develop reduced-risk control strategies for . The insect growth regulator (IGR) novaluron elicits transovarial activity when adult are exposed to it. However, it is not certain whether transovarial effects can be observed when adults that colonize the abaxial leaf surface ingest novaluron residues deposited on the adaxial leaf surface. Experiments were conducted to assess transovarial activity upon exposure to various application rates of novaluron alone and novaluron with various adjuvants. The numbers of nymphs were significantly lower when the full rate of novaluron was applied on the adaxial surface of leaves compared to the number of nymphs on non-treated leaves. The densities of nymphs were not significantly different between the half and full rates of novaluron treatment. When novaluron with various adjuvants was applied to the adaxial surface of the leaves, the densities of nymphs were significantly lower under the novaluron treatments compared to the non-treated leaves, regardless of the type of adjuvant added. There was no significant difference between treatment with novaluron alone and the treatments of novaluron with adjuvants. These data show that transovarial activity was elicited in adults of when novaluron was applied on the adaxial leaf surface.
杜鹃花（L. spp.）是美国东部和西部地区广泛种植的观赏植物。杜鹃网蝽（Stephanitis pyrioides (Scott)，半翅目：网蝽科）是杜鹃花的一种重要害虫。杜鹃网蝽的成虫和若虫会取食杜鹃叶片中的叶绿素，受严重影响的植株会出现白化现象。新烟碱类杀虫剂对防治杜鹃网蝽有效且应用广泛；然而，苗圃种植者和园林专业人士担心其对有益昆虫的非靶标效应，因此需要无新烟碱类药物的植株。显然，有必要为杜鹃网蝽制定降低风险的防治策略。昆虫生长调节剂（IGR）诺瓦隆在成年杜鹃网蝽接触时会引发经卵传递活性。然而，当在叶背表面定殖的杜鹃网蝽成虫摄取沉积在叶面的诺瓦隆残留时，是否能观察到经卵传递效应尚不确定。开展了实验以评估单独使用不同施用量的诺瓦隆以及诺瓦隆与不同助剂组合时的经卵传递活性。与未处理叶片上的若虫数量相比，在叶片正面施用全量诺瓦隆时若虫数量显著更低。诺瓦隆半量和全量处理下若虫密度无显著差异。当将添加不同助剂的诺瓦隆施用于叶片正面时，无论添加何种助剂类型，诺瓦隆处理下的若虫密度均显著低于未处理叶片。单独使用诺瓦隆处理与诺瓦隆加助剂处理之间无显著差异。这些数据表明，当在叶片正面施用诺瓦隆时，杜鹃网蝽成虫会产生经卵传递活性。
