Comparative Study On Populations Of The Striped Stem Borer, Chilo Suppressalis, Hosted On Oryza Sativa And Zizania Latifolia

This thesis was conducted from morphology, sex pheromone, biochemistry and molecular ecology and made a preliminary study on the difference between the striped stem borer populations hosted on oryzasaiiva and zizanialah/olia. The main conclusion was as follows: (I) Twelve quotas of the striped stem borer pupae ( female, male) hosted on oryza sativa and zizania laqfo/ia during overwir)terring generation were analyzed by ANOVA. The result suggested that difference on eight quotas of them was significant and was not diterentiatecl completely. Individuals from differen-t hosts overlapped on twoimension figure that was drawn by principle component analysis. Therefore it was difficult to differentiate the stri ped stem borers hosted on oryza saliva and zizania latjfolia by means of traditional morphology accurately. (IT) The striped stem borer male moths were trapped by sex attractant in different sites (hosts). Wingength of.trappecl male moth was compared by Duncans DMRT. The result illustrated that difference on wingength of trapped moths in different sites was not significant. Therefore it may be believed that the striped stem borers hosted on oryza saUi and zizania lauifolia occurred sympatricly. (111) Esterase isoenzyme of the striped stem borers hosted on oryza sat/va and zizanialatfolia was analyzed by PAGE electrophoresis and scanning. Twentyeven bands were revealed, each of which existed in oryza sat/va or zizania. Protein content of each band was compared by Duncan DMRT. There was no significant difference on protein content of each band except one band (minor band). Clustering analysis showed that the striped stem borers hosted on oryza sativa and zizania lat~folia were not distinctly clustered into group. (N) Marco opulation ecology was combined with micro olecular ecology by RAPDCR. By analyzing quota for average polvnum, average gene diversity and clustering analysis, genome DNA of the striped stem borers was studied. The result suggested that there was difference on different individuals within and between different host populations. Gene diversity in the striped stem borer population hosted on zi:ania /ati/b/ia was higher than that hosted on oryza sat/va. Genetic distance between different host populations was very small. Conclusion was preliminarily drawn from the aboved: From individual perspective, there was some difference in the striped stein borer individuals hosted on oryzu sat/va and zizanialauifo/i However, from population perspective, the relative was close and there was no difference.