Malini Periasamy, Ramasamy Srinivasan, Schafleitner Roland, Muthukalingan Krishnan
World Vegetable Center Shanhua Tainan Taiwan.
Bharathidasan University Tiruchirappalli Tamil Nadu India.
Ecol Evol. 2019 Jul 31;9(16):9239-9272. doi: 10.1002/ece3.5471. eCollection 2019 Aug.
Variations in the functional response of legume pod borer () populations to sex pheromone blends were observed in Asia and Africa. Hence, this study was carried out to understand the differences in pheromone-binding proteins (PBPs) among populations in Asia, Africa, Oceania, and South America. A de novo transcriptome assembly was adopted to sequence the entire transcribed mRNAs in from Taiwan. The raw-sequence data were assembled using homologous genes from related organisms in GenBank to detect PBPs (MvitPBPs). Sections of the cDNA of of different length were used to design primers to amplify the full-length cDNA of PBPs. All three PBP sequences comprised three exons interspersed by two introns. In total, 92 haplotypes, 77 haplotypes, and 64 haplotypes were identified in 105, 98, and 68 individuals, respectively. High pairwise values (0.41-0.73) and phylogenetic analyses distinguished the putative species in South America from those occurring in rest of the world, and possibly two putative subspecies in Asia and Africa. The haplotype networks and Automatic Barcode Gap Discovery analyses also confirmed these results. The negative Tajima's and Fu's values showed the recent demographic expansion of populations. Thus, this study confirmed the presence of different species and/or subspecies in different continents based on the diversity within PBP genes. Additional sampling and studies are suggested for Oceania and South America. The genetic differences among populations should be carefully considered while using sex pheromone lures and bio-control agents.
在亚洲和非洲观察到豆荚螟（Helicoverpa armigera）种群对性信息素混合物的功能反应存在差异。因此，开展本研究以了解亚洲、非洲、大洋洲和南美洲棉铃虫种群中信息素结合蛋白（PBPs）的差异。采用从头转录组组装对来自台湾的棉铃虫的全部转录mRNA进行测序。利用GenBank中相关生物的同源基因对原始序列数据进行组装，以检测棉铃虫PBPs（MvitPBPs）。使用不同长度的棉铃虫cDNA片段设计引物，扩增PBPs的全长cDNA。所有三个PBP序列均由三个外显子和两个内含子相间组成。分别在105、98和68只棉铃虫个体中鉴定出92个棉铃虫单倍型、77个烟芽夜蛾单倍型和64个棉铃虫单倍型。高双核苷酸差异值（0.41 - 0.73）和系统发育分析将南美洲的假定物种与世界其他地区的物种区分开来，亚洲和非洲可能存在两个假定亚种。单倍型网络和自动条形码间隙发现分析也证实了这些结果。负的Tajima's D值和Fu's Fs值表明棉铃虫种群近期的种群扩张。因此，本研究基于PBP基因内的多样性，证实了不同大陆存在不同的棉铃虫物种和/或亚种。建议对大洋洲和南美洲进行额外的采样和研究。在使用性信息素诱捕器和生物防治剂时，应仔细考虑棉铃虫种群之间的遗传差异。
