Mastrangelo Thiago, Fresia Pablo, Lyra Mariana L, Rodrigues Rosangela A, Azeredo-Espin Ana Maria L
Centro de Biologia Molecular e Engenharia Genética, Universidade Estadual de Campinas (CBMEG/UNICAMP), Av. Cândido Rondon 400, 13083-875, Campinas, Brazil.
Departamento de Entomologia e Acarologia, Escola Superior de Agricultura "Luiz de Queiroz" (ESALQ/USP), Av. Pádua Dias 11, 13418-900, Piracicaba, Brazil.
Acta Trop. 2014 Oct;138 Suppl:S26-33. doi: 10.1016/j.actatropica.2014.04.002. Epub 2014 Apr 13.
Cochliomyia hominivorax (Coquerel) is a myiasis fly that causes economic losses to livestock farmers in warmer American regions. Previous studies of this pest had found population structure at north and south of the Amazon Basin, which was considered to be a barrier to dispersal. The present study analyzed three mitochondrial DNA (mtDNA) markers and eight nuclear microsatellite loci to investigate for the first time the genetic diversity and population structure across the Brazilian Amazon region (Amazonia). Both mtDNA and microsatellite data supported the existence of much diversity and significant population structure among nine regional populations of C. hominivorax, which was found to be surprisingly common in Amazonia. Forty-six mtDNA haplotypes were identified, of which 39 were novel and seven had previously been found only at south of Amazonia. Seventy microsatellite alleles were identified by size, moderate to high values of heterozygosity were discovered in all regions, and a Bayesian clustering analysis identified four genetic groups that were not geographically distributed. Reproductive compatibility was also investigated by laboratory crossing, but no evidence of hybrid dysgenesis was found between an Amazonian colony and one each of from Northeast and Southeast Brazil. The results have important implications for area-wide control by the Sterile Insect Technique.
嗜人瘤蝇（Cochliomyia hominivorax，考克雷尔）是一种引起美洲较温暖地区畜牧业者经济损失的蝇蛆病蝇类。此前对这种害虫的研究发现，在亚马逊盆地南北存在种群结构，这被认为是扩散的障碍。本研究分析了三个线粒体DNA（mtDNA）标记和八个核微卫星位点，首次调查了巴西亚马逊地区（亚马孙地区）嗜人瘤蝇的遗传多样性和种群结构。线粒体DNA和微卫星数据均支持在嗜人瘤蝇的九个区域种群中存在大量多样性和显著的种群结构，这种情况在亚马孙地区出人意料地普遍。共鉴定出46种线粒体DNA单倍型，其中39种是新的，7种此前仅在亚马逊河以南发现。通过大小鉴定出70个微卫星等位基因，在所有区域均发现了中度到高度的杂合度值，贝叶斯聚类分析确定了四个非地理分布的遗传组。还通过实验室杂交研究了生殖兼容性，但在一个亚马逊殖民地与巴西东北部和东南部的各一个殖民地之间未发现杂种不育的证据。这些结果对采用昆虫不育技术进行区域控制具有重要意义。
