Habitat-related mtDNA polymorphism in the stored-bean pest Callosobruchus chinensis (Coleoptera: Bruchidae)

Abstract

The genetic diversity of populations of the azuki bean beetle, Callosobruchus chinensis (Linnaeus) from natural, pre-harvest and post-harvest sites, was investigated to understand population structure and gene flow. A 522-bp fragment of the mitochondrial gene COI was sequenced for eight populations of C. chinensis from Japan, Korea and Taiwan collected from different habitats. Six haplotypes were detected, one of which, U1, occurred most frequently and widely. The following hypotheses were tested as a cause of the wide distribution of haplotype U1; (i) topographical separation (by national boundaries), (ii) host plant species, and (iii) habitat type (natural, pre-harvest crop, or post-harvest storage). Categorization of collection sites by country or by host species did not yield differences in the occurrence of haplotype U1, but habitat type did. Populations utilizing cultivated post-harvest hosts that were mass stored were highly likely to be the common haplotype, whereas host plants in natural habitats away from agriculture were utilized by populations with locally characteristic haplotypes. Sampling of commercial beans for quarantine and export purposes indicated that gene flow in C. chinensis was largely unidirectional into Japan at the present time.

Global Genetic Differentiation in a Cosmopolitan Pest of Stored Beans: Effects of Geography, Host-Plant Usage and Anthropogenic Factors

“…In crop pests, the trade of crops across the world tends to generate a global mixing of genetic variants in pest populations, whether these were generated and maintained either allopatrically (e.g., [1],[2]) or sympatrically (e.g., [3],[4]). However, the relative contributions of allopatric or sympatric genetic differentiation versus global genotypic intermixing by natural [5] or human-aided [6]–[8] dispersal to global (continental and island) population structures has rarely been evaluated quantitatively (but see [9],[10]). …”

“…Association with specific host plants may allow the formation of genetically distinct pest host races in some cases [6], but not in others [5]. It has been suggested that an increased use of dry crops may have led to the multivoltine life cycles, polyphagy and expanded geographic distribution of stored bean pests [11]–[16].…”

Wolbachiagenome integrated in an insect chromosome: Evolution and fate of laterally transferred endosymbiont genes

“…The current worldwide distribution of the pest of stored beans is probably mediated by human activities (Borowiec 1987). Mitochondrial DNA analysis of Asian populations of C. chinensis certainly showed that insect samples collected from bean field/storage/ market exhibited specific genotypes, while insect samples collected from wild leguminous plants were genetically diverse (Tuda et al 2004). Hence, it is expected that a worldwide survey of wild C. chinensis populations not infesting agricultural beans but feeding on wild legumes would lead to key discoveries, such as insect populations without the transferred Wolbachia genes or insect populations infected with a relict bacterial Wolbachia endosymbiont closely related to the transferred Wolbachia genome.…”

Resistance of Faba Bean and Pea Germplasm to <I>Callosobruchus chinensis</I> (Coleoptera: Bruchidae) and Its Relationship With Quality Components

“…; Li and Zhu 2009). As is typical of the life history of the Bruchidae, larvae bore into legume seeds on hatching and feed on the seed and consume the cotyledons (Tuda et al 2004). They pupate and metamorphose into adults within the seed and emerge to seek mates and new hosts, which causes secondary infestation and often causing considerable damage to stored food legumes (Tuda et al 2004).…”

“…As is typical of the life history of the Bruchidae, larvae bore into legume seeds on hatching and feed on the seed and consume the cotyledons (Tuda et al 2004). They pupate and metamorphose into adults within the seed and emerge to seek mates and new hosts, which causes secondary infestation and often causing considerable damage to stored food legumes (Tuda et al 2004). Usually, the afßicted legumes show an infestation percentage of 30 to 64%, or even as high as 80 to 100%, thereby signiÞcantly decreasing or even completely losing the thousand-kernel weight, nutritive value, and germination rate, which makes them unÞt for human consumption or for agricultural and commercial use (Umrao and Verma 2002, Chaubey 2008, Duan et al 2014.…”