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本文以光照周期和温度与发育、滞育关系的试验为基础,探讨了草地螟的滞育诱导因素和临界条件,以探索越冬虫源。证实草地螟在前蛹期可出现滞育,其主要诱导因素为当代幼虫期的光照周期和温度,这两者有交互作用,趋向高适温和长光照时滞育比率降低,直至不出现滞育,属兼性滞育。计算出滞育比率在50—90％之间的相应条件光照周期为13、16小时,温度为25.4—23.3℃、18.3—14.5℃。认为这一范围即为滞育临界区。讨论提出我国北方各地草地螟种群,通过迁飞互相渗透,成为同一地理种群,在其分布区内存在着适于越冬的地带。这一地带的虫源成为我国周年种群发生和长周期发展消长的基础。
In this paper, the diapause inducing factors and critical conditions of Meadow Stem Borer were studied on the basis of the experiment of relationship between light cycle and temperature and development and diapause, in order to explore the overwintering insect source. Confirmed that diapause occurred in the pupal stage, the main inducing factor was the light cycle and temperature of contemporary larval stage, both of which had an interaction. The diapause rate of high and moderate temperature and long-term light decreased until diapause did not occur , Is a facultative diapause. The corresponding conditions for diapause rates between 50-90% were calculated as 13,16 hours with temperatures of 25.4-23.3 ° C and 18.3-14.5 ° C. That this range is the critical area for diapause. The discussion proposed that the populations of Meadow Stem Borer in northern China should migrate to and penetrate each other to become the same geographical population. There exists a suitable zone for overwintering in their distribution areas. The source of this zone has become the basis for the occurrence and development of the annual population in our country.