Comparison of reproductive strategy between Chrysolina aurichalcea species complex by using the methods of cytogenetics and population genetics.

1994 Fiscal Year Final Research Report Summary

• Project/Area Number: 05640708
• Research Category: Grant-in-Aid for General Scientific Research (C)
• Allocation Type: Single-year Grants
• Research Field: 生態
• Research Institution: Shinshu University
• Principal Investigator: FUJIYAMA Shizuo Shinshu University, Department of Biology, Associate Professor, 理学部, 助教授 (70109164)
• Project Period (FY): 1993 – 1994
• Keywords: reproductive strategy / species complex / adult behavior / life history strategy / mixed population / species interaction / color dimorphism / diurnal activity

Research Abstract

The comparison of reproductive strategy between two species of Chrysolina aurichalcea complex having different chromosome numbers were studied under contant environmenal and field conditions. The most of the behaviors of both adults were nearly the same but the immature adults with 41 chromosome type were active on the host under light while those with 31 type (follow to above) remained resting under the host. The reproductive curves were different, the former having short reproductive life span but the latter, long one. These differences might explain their parapatric distribution, because early reproductionof former dominates at mountainous areas. The host plants defoliate earlier in autumn than those at open lands. Further, the mixed population of the two species showed non-symmetric cross mating, namely 32*x41* is more common than 42*x31*, though the intra-specific matings were the most common. The results might cause the selection to the segregation of reproductive season in the two speceis.