Factors Causing the Difference in Parasitism Pattern between Two Parasitoid Wasps, Atanycolus initiator(FABRICIUS)and Spathius brevicaudis RATZEBURG(Hymenoptera:Braconidae), on Subcortical Beetles in Japanese Pine Trees

概要

論文の詳細を見る
The seasonal changes in species composition and spatial distribution of the subcortical beetles infesting Japanese pine trees and their two major parasitoid wasps, Atanycolus initiator and Spathius brevicaudis, were examined to analyze factors causing the difference in parasitism patterns between the wasps in the trees. Both parasitoids emerged between April and November, during which time the species composition of the host larvae changed largely with the season. S. brevicaudis could exploit smaller host species in which A. initiator with its larger body size could not attain a successful development. Conversely, A. initiator with its longer ovipositor could parasitize the hosts distributed almost anywhere on the tree stems, prevailing over S. brevicaudis particularly on the lower part of the stems having a thick bark. It was suggested that the seasonal changes in the species and the size composition of host beetles, and/or their spatial distribution, are likely to be the crucial factors responsible for the differences in parasitism patterns between the two parasitoid species.
日本応用動物昆虫学会の論文
1991-11-25