Study on the evolution of obligatory cecidophagy as an example of an indirect host utilization through food sources induced by a third organism

Research Project

Project/Area Number	21770095
Research Category	Grant-in-Aid for Young Scientists (B)
Allocation Type	Single-year Grants
Research Field	Biodiversity/Systematics
Research Institution	National Institute for Agro-Environmental Sciences
Principal Investigator	YOSHITAKE Hiraku 独立行政法人農業環境技術研究所, 農業環境インベントリーセンター, 主任研究員 (50517662)
Project Period (FY)	2010 – 2012
Project Status	Completed (Fiscal Year 2012)
Budget Amount *help	¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000) Fiscal Year 2012: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000) Fiscal Year 2011: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000) Fiscal Year 2010: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000) Fiscal Year 2009: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
Keywords	生物多様性 / 生物間相互作用 / 資源利用 / 間接効果 / 植食者 / クロツヤサルゾウムシ / タニウツギ / 虫こぶ
Research Abstract	Obligatory cecidophagy is a unique insect-plant interaction, because it is an indirect host plant utilization through galls induced by a third organism. The genus Wagnerinus (Coleoptera: Curculionidae) is known to contain species feeding exclusively on axillary bud galls induced on Weigela species (Caprifoliaceae) by a gall midge (Diptera). In this research project, an evolutionary study of the cecidophagous habit of Wagnerinus weevils was conducted in order to consider the adaptive significance of obligatory cecidophagy. Ecological data were gathered through field surveys and experiments. Phylogenetic relationships among Wagnerinus weevils were inferred from sequences of the mitochondrial COI gene. The evolutionary process of the obligatory cecidophagy was inferred from the results of phylogenetic analyses and ecological studies. A classification system of the genus was reconstructed based on various biological data accumulated in the course of this study.