Entomological Science (2011) 14, 166-172

Hiroyuki Mano and Yukihiko Toquenaga (2011)
Contest-type competition between age classes in scramble-type Callosobruchus maculatus (Coleoptera: Bruchidae)
Entomological Science 14 (2), 166-172
Abstract: We examined the effect of age differences on competition type in individuals of a scramble-type strain of Callosobruchus maculatus (F.). When oviposition of two individuals on a bean was manipulated to introduce time intervals using two lines with different adult body colors, the frequency of two-adult emergence decreased with the introduction of sequential oviposition. This result indicates that an age difference between two individuals induces contest competition. The frequency of adult emergence in older individuals decreased, whereas in younger individuals it increased with the introduction of sequential oviposition. Using a dissecting microscope, we observed that bodies of older individuals that died in the bean during the 4-day oviposition interval were crushed at the pupal stage under the pupal chambers of younger individuals. These results show that an age difference between two larvae in a bean causes contest competition due to one-sided interference by a younger individual during pupation of an older individual. Based on these experimental results, we discuss the ecological cause of contest competition and the population-level consequences of identified interactions in scramble-type C. maculatus.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Hiroyuki Mano

Research topic(s) for pests/diseases/weeds:
general biology - morphology - evolution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Callosobruchus maculatus