Hlaoui Amen, Boukhris-Bouhachem Sonia, Sepúlveda Daniela A, Correa Margarita C G, Briones Lucía M, Souissi Rebha, Figueroa Christian C
Laboratoire de Protection des Végétaux, Institut National de Recherche Agronomique de Tunisie INRAT, Rue Hédi Karray, Ariana 2049, Tunisia.
Département Santé Végétale et Environnement, Institut National Agronomique de Tunisie INAT, Université de Carthage, 43 Avenue Charles Nicolle, Cité Mahrajène Tunis 1082, Tunisia.
Insects. 2019 Oct 1;10(10):330. doi: 10.3390/insects10100330.
The peach potato aphid, (Sulzer), is a worldwide pest of many crops, and the most important aphid pest of peach and potato crops in Tunisia, mainly due to virus transmission, for which insecticides are frequently applied. We studied the genetic structure of populations in Tunisia, in order to further our understanding of the biotic and abiotic factors shaping populations and to predict their evolutionary responses to the present management practices. We monitored peach orchards and seed potato crops in different seasons and regions from 2011-2013 and in 2016 (19 populations), assessing the genetic diversity of at six microsatellite loci. Temporal and spatial changes in the frequency and distribution of 397 genotypes in 548 sampled aphids were studied. Only 37 genotypes were found more than once (clonal amplification), as most genotypes were found only once (91.60% in peach; 88.73% in potato crops). A similarly high genetic diversity was observed in aphids sampled from peach (G/N = 0.76; Ho = 0.617) and potato (G/N = 0.70; Ho = 0.641). Only a weak genetic differentiation among populations was found, mainly between geographic locations. Clustering analysis revealed genotypes to be grouped mainly according to host plant. The availability of the primary host, high proportion of unique genotypes, high genetic diversity and lack of structuring suggest that the aphid reproduces mainly through cyclical parthenogenesis in Tunisia. On the other hand, we provide a farm-scale study that shows how easily can colonize different areas and hosts, which may have important implications in relation to plant virus vectoring.
桃蚜（Myzus persicae (Sulzer)）是一种危害多种作物的世界性害虫，也是突尼斯桃树和马铃薯作物最重要的蚜虫害虫，主要因其传播病毒，为此经常使用杀虫剂。我们研究了突尼斯桃蚜种群的遗传结构，以便进一步了解塑造种群的生物和非生物因素，并预测它们对当前管理措施的进化反应。我们在2011年至2013年以及2016年监测了不同季节和地区的桃园和种用马铃薯作物（19个种群），评估了桃蚜在六个微卫星位点的遗传多样性。研究了548只采样蚜虫中397种基因型的频率和分布的时空变化。仅发现37种基因型出现不止一次（克隆扩增），因为大多数基因型只出现一次（桃树中为91.60%；马铃薯作物中为88.73%）。从桃树（G/N = 0.76；Ho = 0.617）和马铃薯（G/N = 0.70；Ho = 0.641）采样的蚜虫中观察到了同样高的遗传多样性。仅在种群间发现了微弱的遗传分化，主要存在于地理位置之间。聚类分析表明基因型主要根据寄主植物进行分组。主要寄主的可获得性、独特基因型的高比例、高遗传多样性和缺乏结构表明，突尼斯的桃蚜主要通过周期性孤雌生殖进行繁殖。另一方面，我们提供了一项农场规模的研究，表明桃蚜能够多么容易地定殖于不同区域和寄主，这可能对植物病毒传播具有重要意义。
