摘要
对江苏和安徽几个不同稻螟发生区螟卵寄生蜂的调查表明 ,稻螟赤眼蜂为优势种。在一代二化螟中 ,以二化螟特大发生的常熟地区稻螟赤眼蜂寄生率最高达 1 0 0 % ,每卵块羽化寄生蜂数也高达 82 3头 ;三化螟和二化螟发生均较重的安徽省和县稻螟赤眼蜂寄生率为 1 7 1 % ,每一卵块羽化的蜂仅 3 5头。由于地区间卵块大小有差别 ,寄生蜂对二化螟实际控制效果以金坛西部最高。一代三化螟中 ,常熟及金坛西部的寄生率均高达 1 0 0 % ,其它地区寄生率为 46 7%～ 79 1 % ,每一卵块羽化的蜂数则较少。赤眼蜂在不同代次螟虫间变动较大 ,金坛东部地区 ,一代二化螟到二代二化螟 ,每卵块寄生蜂数量由 3 8 3头下降为 0头 ,这主要是由于化学农药影响。在和县 ,寄生蜂随三化螟代次增加而增加 ,但在高淳 ,寄生蜂却在二代出现最低峰 ,三代最高。寄生蜂性比也因地区、螟虫种类和代次不同而变化。
Egg parasitism of rice stem borers in Changshu, Jiangyin, Jintan, Gaochun of Jiangsu province, and Hexian, Anhui province with different stem borer occurring patterns were investigated. The results showed that Trichogramma japonicum Ashmead was the dominant species in all these regions. There was significant difference in parasitism of striped stem borer in different regions. 100% egg masses in Changshu was parasitized by Trichogramma in the 1st generation of Chilo supperssalis and 82.3 wasps emerged from each egg mass. And in western Jintan only 17.1% eggs was parasitized and 3.5 wasps emerged per egg mass. Since the egg masses differed in size in different regions, so the control efficacy in Jintan was considered as the most prominent. In 1st generation Tryporyza incertulas eggs in Changshu and eastern Jintan were 100% parasitized and more wasps (31.3-28.7 wasps) emerged per egg mass than those in the other regions. Egg parasitism of rice borers of different generations varied greatly, e.g. in Jintan 38.3 wasps emerged per egg mass in the 1st generation, but no egg was parasitized in the 2nd generation, because frequent use of pesticides in the rice fields was fatal to Trichogramma wasps. In Hexian egg parasitism was higher in the 2nd generation than that of the 1st generation. The sex ratio of the Trichogramma wasps also varied with borer species and generations.
出处
《中国生物防治》
CSCD
北大核心
2002年第1期13-16,共4页
Chinese Journal of Biological Control
基金
"九五"国家重点攻关 (96 - 0 0 5 - 0 1- 0 1)
江苏省重大攻关 (BG96 5 13- 2 )项目
