黄花蒿是绿盲蝽重要的秋季寄主，其释放的挥发物对绿盲蝽具有吸引作用。黄花蒿中的挥发性物质青蒿酸是合成青蒿素的前体物质，在中草药领域被深入研究。迄今为止，关于青蒿酸调控绿盲蝽趋向行为的生物学作用研究鲜有报道。本研究使用顶空固相微萃取（HS-SPME）收集幼苗期黄花蒿的挥发物，通过气相色谱-质谱联用仪（GC-MS）分析，在挥发性样品和研磨样品中检测到的青蒿酸的浓度分别为11.03±6.00 ng h^-1和238.25±121.67 ng h^-1。随后，在工程酿酒酵母中表达了青蒿酸合成的关键基因细胞色素P450（cyp71av1）加入外源的青蒿醇或青蒿醛为催化底物，工程酿酒酵母能够合成青蒿酸。在触角电位（EAG）测试中，3日龄的绿盲蝽成虫对青蒿醇、青蒿醛和青蒿酸均表现出强烈的电生理反应。行为学试验表明，浓度为10 mmol L^-1的青蒿酸和青蒿醇能够显著吸引3日龄的雌性绿盲蝽虫成虫，而10 mmol L^-1 青蒿酸和青蒿醛明显吸引3日龄的雄性绿盲蝽虫成虫。 因此， 青蒿酸及其前体物质可作为潜在的绿盲蝽引诱剂组分，用于设计绿盲蝽的综合防治策略。

Cry toxins produced by Bacillus thuringiensis (Bt) are effective biological insecticides against certain insect species. However, there are potential risks of the evolved resistance of insects to Cry toxin owing to decreased binding of toxins to target sites in the brush border membranes of the larva midgut. The Cry toxins with different binding sites in the larval midgut have been considered to be a good combination to deploy in delaying resistance evolution. Bioassay results demonstrated that the toxicity of different Cry toxins ranked differently for each species. The toxicity ranking was Cry1Ac>Cry1Ab>Cry2Ab for Helicoverpa armigera, Cry1B>Cry1C>Cry2Ab for Spodoptera exigua, and Cry2Ab>Cry1B> Cry1C for S. litura. Only Cry2Ab was toxic to Agrotis ipsilon. Binding experiments were performed with 125I-Cry1Ab, 125ICry1Ac, 125I-Cry1B, 125I-Cry1C, 125I-Cry2Ab and the brush border membranes vesicles (BBMV) from H. armigera, S. exigua, S. litura and A. ipsilon. The binding of Cry1Ab and Cry1Ac was shown to be saturable by incubating with increasing concentrations of H. armigera BBMV (Kd=(45.00±2.01) nmol L-1 and (12.80±0.18) nmol L-1, respectively; Bmax=(54.95±1.79) ng and (55.44±0.91) ng, separately). The binding of Cry1B was shown to be saturable by incubating with increasing concentrations of S. exigua BBMV (Kd=(23.26±1.66) nmol L-1; Bmax=(65.37±1.87) ng). The binding of 125ICry toxins was shown to be non-saturable by incubating with increasing concentrations of S. litura and A. ipsilon BBMV. In contrast, Cry1B and Cry1C showed some combination with the BBMV of S. litura, and a certain amount of Cry2Ab could bind to the BBMV of A. ipsilon. These observations suggest that a future strategy could be devised for the focused combination of specific cry genes in transgenic crops to control target pests, widen the spectrum of insecticide effectiveness and postpone insect resistance evolution.

A chemosensory protein named HarmCSP5 in cotton bollworm Helicoverpa armigera (Hübner) was obtained from antennal cDNA libraries and expressed in Escherichia coli. The real time quantitative PCR (RT-qPCR) results indicated that HarmCSP5 gene was mainly expressed in male and female antennae but also expressed in female legs and wings. Competitive binding assays were performed to test the binding affinity of recombinant HarmCSP5 to 60 odor molecules including some cotton volatiles. The resules showed that HarmCSP5 showed strong binding abilities to 4-ehtylbenzaldehyde and 3,4-dimethlbenz aldehyde, whereas methyl phenylacetate, 2-decanone, 1-pentanol, carvenol, isoborneol, nerolidol, 2- nonanone and ethyl heptanoate have relatively weak binding affinity. Moreover, the predicted 3D model of HarmCSP5 consists of six α-helices located among residues 33-38 (α1), 40-48 (α2), 62-72 (α3), 80-96 (α4), 98-108 (α5), and 116-119 (α6), two pairs of disulfide bridges Cys49-Cys55, Cys75-Cys78. The two amino acid residues, Ile94 and Trp101, may play crucial roles in HarmCSP5 binding with ligands and need further study for confirmation.

Cry toxins produced by Bacillus thuringiensis (Bt) are effective biological insecticides against certain insect species. In this study, bioassay results indicated that Cry1B and Cry1C were toxic to Spodoptera exigua. We also identified a cadherin-like gene in S. exigua that could enhance the toxicity of Cry1B and Cry1C. The cadherin-like gene identified from the larvae midgut tissue was cloned by reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE). The full-length cDNA of the gene consisted of 5 220 bp encoding 1 740 amino acid with a predicted molecular mass of 196 kD. BLAST search analysis showed that the predicted amino acid sequence had a high sequence identity to the published sequences of cadherin-like proteins from other Lepidoptera insects. Spatial expression of the cadherin-like gene detected by qRT-PCR analysis revealed that the cadherin-like gene was mainly present in the gut of 4th instar larvae and during different life stages. The results suggested that the commercial development of this synergist has the potential to enhance Cry1B and Cry1C toxicity against Lepidoptera insects.