北京顺义区八字地老虎的种群监测与发生世代分析

为了解北京地区八字地老虎的种群动态及其发生危害地位,2012年和2013年,在北京市顺义区龙湾屯镇使用佳多虫情测报灯对地老虎成虫种群动态进行了持续监测。监测结果表明,八字地老虎已成为当地最主要的地老虎类害虫,成虫的优势度最高可达83.8%,已超过常年优势种小地老虎。八字地老虎在北京顺义1年可见3代成虫,越冬代成虫期为5月中下旬,一代成虫期是7月中下旬,二代成虫期持续时间最长,从9月初开始,10月上旬逐渐消失。监测表明,八字地老虎在局部地区存在严重发生的可能性,建议各监测点密切关注其发生动态,为今后八字地老虎的预警和防治提供科学依据。

Monitoring the population dynamics and generations of Xestia c-nigrum (Lepidoptera: Noctuidae) in Shunyi, Beijing

In order to know the population dynamics of Xestia c-nigrum and ascertain its occurrence status in Beijing, Jiaduo forecast light for insects was being in operation at Longwantun of Shunyi District, Beijing, to catch the moths of cutworms during the monitoring seasons of 2012 and 2013. From the continuous monitoring and other evidences, we found out that X.c-nigrum had become a primary cutworm pest, and dominance of the adults was up to 83.8%, which was already more than the traditional dominant species Agrotis ipsilon. X.c-nigrum had 3 generations in a year, adult duration of overwintering generation was from the mid to late May, The first generation appeared in mid July and disappeared in late July. Duration of the second generation was the longest, which emerged from the beginning of September and disappeared until early October. Monitoring data showed that X. c-nigrum might cause great damages in some places, so we suggest that each monitoring station should pay close attention to the dynamic of X. c-nigrum and provide the basis data for early forecasting and control.