Population genetic structure of Chilo suppressalis (Walker) (Lepidoptera: Crambidae): strong subdivision in China inferred from microsatellite markers and mtDNA gene sequences

Abstract

Chilo suppressalis (Walker) displays significant geographical differences in ecological preference that may be congruent with patterns of molecular variation. To test this, we collected and analysed 381 individuals of this species from cultivated rice at 18 localities in China during the rice-growing season of 2005-2006. We used four microsatellite DNA markers and four mitochondrial DNA gene fragments. We found that this species is highly differentiated, coupled with an estimated population expansion date of at least 60 000 bp. Phylogenetic analyses, Bayesian clustering, and phylogeographical analyses of statistical parsimony haplotype network consistently divided the populations into three clades: a central China (CC) clade, a northern plus northeastern China (NN) clade and a southwestern China (SW) clade. Analysis of molecular variance indicated a high level of geographical differentiation at different hierarchical levels [F(ST) for microsatellite markers, COI, COII, 16S and ND1 is 0.06004 (P < 0.0001), 0.27607 (P < 0.0001), 0.22949 (P < 0.0001), 0.19485 (P < 0.0001) and 0.29285 (P < 0.0001), respectively]. Isolation by distance appeared among the samples from within China (r = 0.404, P = 0.0002); N(e)m values estimated using a coalescent-based method were small (< 2 migrants per generation), suggesting that the observed levels of differentiation are a result of migration-drift equilibrium. Our results imply that the genetic differentiation of this borer, which is approximately in accordance with its observed number of generations per year in different Chinese geographical regions, is probably attributed to climatic and/or geological events (e.g. the last glacial maximum) and subsequently strengthened by the domestication of rice.

Genetic Diversity in Apple Fruit Moth Indicate Different Clusters in the Two Most Important Apple Growing Regions of Norway

“…There are several other possible factors, which might be responsible for genetic differentiation among populations in insects species; low dispersal ability [15,55], habitat fragmentation [56][57][58] and host plant availability [6,55,59]. A. conjugella in different regions could be genetically distinct, considering the differences in eco-geographic factors and variable presence of this insect in the rowan and apple plants in Norway.…”

Genetic diversity of rice stem borer (Chilo suppressalis Walker) from Northern Iran and comparison with other countries

“…The similarity of the Iranian population Kiakola with one population from China suggests China as the origin of C. suppresalis. High genetic diversities of C. suppressalis were observed among the populations of stem borer from China (Meng et al, 2008), high diversities could be bound to long-time settlement of the pest in this country, the large extent of China, large distance between examined areas, climate variations and so on. However, the results of two mitochondrial genes (COI and COII) also indicated no significant genetic diversity among some Chinese populations (Liu et al, 2013).…”

“…Different DNA markers, such as microsatellite, nuclear genes, RAPDs and those derived from mitochondrial DNA, have been used in other infested countries such as China, Japan and South Korea to study genetic variation in striped stem borer populations (Ishiguro & Tsuchida, 2006;Meng, et al, 2008;Liu et al, 2013). However no research was previously carried out about genetic diversity and relationships of different populations of this pest in Iran, with the exception of the study of genetic diversity of stem borer among populations from the Guilan and west Mazandaran province by RAPD markers (Farahpour Haghani et al, 2014).…”

“…Ishiguro and Tsuchida (2006) investigated the polymorphic microsatellite loci for the rice stem borer. The genetic diversity of C. suppressalis, was investigated among 18 Chinese populations by microsatellite, COI, COII, 16S and ND1 (Meng et al, 2008). High genetic diversity was found among these populations, this was expected considering the large area of the country and climate variation.…”

Genetic variation of Chilo suppressalis Walker (Lepidoptera: Pyralidae) populations in Guilan and west of Mazandaran provinces analysed with RAPD markers

“…Up to now, despite the significance of RSSB, no assessment of the study about the genetic structure of RSSB by using molecular markers has been done in Iran. Papers on RSSB in other countries are limited study on geographic variation in susceptibility to Bacillus thuringiensis in China (Meng et al 2003), effects of Bt transgenic rice on RSSB and its consequences on egg parasitoid, Trichogramma brassicae (Marzban 2012), RSSB resistance to pesticides (Cao et al 2004;Li et al 2007), biochemical study (Zibaii 2008), geometric morphometric study (Zahiri et al 2006), isolation and characterisation of four polymorphic microsatellite loci ( Jiang et al 2005;Ishiguro et al 2006;Meng et al 2008), characterisation of complete mitochondrial genomes (Chai et al 2012), and limited divergence among RSSB populations caused by gene flow in southeast China . The objective of the present first study on genetic diversity of Chilo suppressalis in Iran is to explore the level of RAPD genetic variation among active RSSB populations in Guilan and west part of Mazandaran provinces, without any distinctive morphological deferens.…”