棉田十一星瓢虫的种群动态

2001年5月15日至9月17日系统调查了不同棉花品种的棉田十一星瓢虫的种群动态。结果表明：尉犁县棉田瓢虫主要为十一星瓢虫（Coccinella undecimpunctata Linnaeus），它是控制棉田棉蚜危害的优势种天敌，占棉田瓢虫总数的81％。十一星瓢虫在棉田中的消长规律为：越冬代成虫5月底开始进入棉田取食棉蚜；卵期5月29日至7月14日，6月下旬进入产卵盛期；幼虫期6月5日至7月31日，高峰期7月7日左右；蛹期6月20日至7月21日，高峰期7月7日左右；成虫期6月20日至9月中下旬，高峰期7月7日至7月14日。十一星瓢虫的种群动态与棉田棉蚜数量有明显的跟随反应，棉田中的早播玉米带、棉田边缘的胡杨和沙枣树的树皮缝隙是瓢虫夏眠的场所。

The Population Dynamics of Coccinella undecimpunctata in the Cotton Fields in Yuli County, Xinjiang

The ladybird groups and the population dynamics of Coccinella undecimpunctata in the cotton fields of the different cotton varieties in Yuli County, Xinjiang, were investigated during the period from May 15 to September 17, 2001. The results show that the dominant species in the cotton fields is Coccinella undecimpunctata. The population dynamics of Coccinella undecimpunctata in the cotton fields shows that the egg period is from May 29 to July 14 and the fecundity is in the late June; the larva period is from June 5 to July 31 and its boom is about on July 7; the pupa period is from June 20 to July 21 and its boom is about on July 7; the adult period is from June 20 to mid or late September and its boom is from July 7 to 14. The population of Coccinella undecimpunctata changes with the number of cotton aphids, and Coccinella undecimpunctata aestivate generally on the girdles of spring maize in the cotton fields, foliages and in the bark apertures of Popular diversifolia and Elaeagnus angustifolia around the cotton fields.