滇西保山地区草地贪夜蛾的种群动态及其对气候因子的响应

Population dynamics of the fall armyworm(Spodoptera frugiperda)and its response to climatic factors in Baoshan,Yunnan

草地贪夜蛾(Spodoptera frugiperda)是联合国粮农组织全球预警的重大农业害虫,成虫具有较强的迁飞能力.滇西保山地区是草地贪夜蛾进入我国最早的地区之一,为监测其种群动态,本研究在云南省保山隆阳区芒宽乡和施甸县旧城乡,采用主要成分为顺-9-十四碳烯乙酸酯和顺-7-十二碳烯乙酸酯的草地贪夜蛾性信息素,通过带气候仪的自动监测设备对草地贪夜蛾成虫开展为期2 a的种群监测,并分析种群动态与气候因子的相关性.结果表明,草地贪夜蛾在云南保山玉米种植区全年有发生,种群波动在芒宽乡比旧城乡大,种群活动高峰出现在3—5月.与2020年相比,2021年草地贪夜蛾种群数量明显减少,这可能与开展的防治措施有关.在草地贪夜蛾种群发生的高峰月份,种群日动态变化分析显示,旧城乡和芒宽乡诱集到虫口数量最多的时间分别为晚上21:00和凌晨3:00;草地贪夜蛾种群存在一定的时空变化规律,但2个监测地的种群发生规律存在差异.此外,草地贪夜蛾种群动态受温湿度影响,与温度和湿度分别呈三次曲线和二次曲线关系,其成虫活动的最适温度为26.21℃,最适湿度为53.0%.研究结果为草地贪夜蛾的防控提供了科学依据.

Spodoptera frugiperda(fall armyworm,FAW)has been reported as a major agricultural pest worldwide by the United Nations Food and Agriculture Organization.Adult FAWs exhibit strong migratory capability.Baoshan,located in western Yunnan,is one of the early entry points for FAW in China.In this study,(Z)-9-tetradecenyl acetate and cis-7-dodecenyl acetate,the primary components of sex pheromone,were employed to monitor FAW populations in automatic insect monitors equipped with a microclimate instrument.This study was conducted over 2-years at Mangkuan and Jiucheng,located in the Baoshan region.Monitoring data showed that FAW occurred throughout the year in the corn planting area of Baoshan,and the population dynamics were greater at Mangkuan than at Jiucheng.The population peaks appeared from March to May.The FAW population density in 2021 was significantly lower than that in 2020 during the peak months,which may be due to the implementation of effective control measures.During the peak months of FAW occurrence,the daily activity peaked at 10:00 pm in Jiucheng and 03:00 am in Mangkuan.These results suggest that FAW populations exhibit spatiotemporal changes but without uniform monthly or diurnal occurrence patterns at the two sites.Furthermore,FAW population dynamics showed a cubic and quadratic relationship with temperature(optimum temperature of 26.21℃)and humidity(optimum humidity of 53.0%),respectively.Our results provide helpful scientific evidence for the prevention and control of FAW.