Karyotype variations in Italian populations of the peach-potato aphid Myzus persicae (Hemiptera: Aphididae)

Abstract

In this study, we present cytogenetic data regarding 66 Myzus persicae strains collected in different regions of Italy. Together with the most common 2n = 12 karyotype, the results showed different chromosomal rearrangements: 2n = 12 with A1-3 reciprocal translocation, 2n = 13 with A1-3 reciprocal translocation and A3 fission, 2n = 13 with A3 fission, 2n = 13 with A4 fission, 2n = 14 with X and A3 fissions. A 2n = 12-13 chromosomal mosaicism has also been observed. Chromosomal aberrations (and in particular all strains showing A1-3 reciprocal translocation) are especially frequent in strains collected on tobacco plants, and we suggest that a clastogenic effect of nicotine, further benefited by the holocentric nature of aphid chromosomes, could be at the basis of the observed phenomenon.

Genomic and Cytogenetic Localization of the Carotenoid Genes in the Aphid Genome

“…The chromosome number and karyotype structure of aphids have been studied in a large number of species over the past few decades showing that chromosomal variations are relatively common within some species [Blackman, 1980;Manicardi et al, 2002Manicardi et al, , 2015aMonti et al, 2011Monti et al, , 2012aRivi et al, 2012Rivi et al, , 2013Mandrioli et al, 2014a]. This is not surprising since aphids have holocentric chromosomes with kinetic activity spread along the whole chromosome axis [Blackman, 1980].…”

“…The peach potato aphid Myzus persicae (Sulzer) is one of the most extensively studied aphid species in the world in terms of lifecycle, migration, population genetics, and cytogenetics, and several molecular and cytogenetic analyses have been performed in order to elucidate the structure of its genome and karyotype [Blackman, 1980;Manicardi et al, 2002Manicardi et al, , 2015aMonti et al, 2011Monti et al, , 2012aRivi et al, 2012Rivi et al, , 2013.…”

“…The standard karyotype of M. persicae comprises 12 chromosomes, including 5 pairs of homologous autosomes and 2 X chromosomes, but several variations in chromosome number and structure have been recently observed in Italy and Greece [Monti et al, 2011[Monti et al, , 2012aRivi et al, 2012Rivi et al, , 2013Kati et al, 2014]. In particular, the most common M. persicae chromosomal variant consists of a reciprocal translocation between autosomes 1 (A1) and 3 (A3) resulting in females with 12 chromosomes with a marked structural difference in heterozygotes [Blackman, 1980;Manicardi et al, 2015b].…”

Identification of Generalist and Specialist Phenotypes of the Peach-Potato Aphid <i>Myzus persicae</i> (Insecta : Hemiptera : Aphididae) in Agroecosystem of Northeast India

“…This view is vindicated by Ramsey et al 28 who identified 2423 novel genes specific to M. persicae from a large collection of aphids from different geographical regions and found high polymorphism in nucleotide sequence tags. The present and some previous studies from Tripura 2,5,8,19,26,27 bring out that discrimination in host plant utilization in asexual lineages of M. persicae and other aphid species appears to be a common phenomenon and, therefore, requires a focussed approach in understanding aphid-food plant relationship and management of aphid populations on specific host plants 2,4,7,22 .…”

“…Distinct phenotypes and genotypes of M. persicae have been recorded from different parts of the world under diverse conditions and from different host plants, both wild and cultivated 5,17,23,25,26 . The recorded differences in phenotypes, based on differences in genotypes, are from the secondary host plants of diverse plant families which vary from region to region 27,28 . Apterous viviparous female morph of aphids, which is the colonizer of food plants, appears to undergo constant changes in its structures and functions in order to adapt to variable conditions of host environments including presence of allelochemicals which profoundly influence the selection process of host plant 28,29 .…”