云南省德宏州亚洲玉米螟发生动态及主要危害区域调查

利用亚洲玉米螟信息素监测亚洲玉米螟在云南省德宏州的种群动态,结果表明,亚洲玉米螟在德宏州发生可分为两种类型,一是在低海拔(1 000m)地区亚洲玉米螟全年均有发生,二是在高海拔(1 200m)地区集中在4-8月份发生为害。亚洲玉米螟在德宏州世代重叠严重,因海拔高度不同,每年发生4~7代。高海拔地区以老熟幼虫滞育越冬,低海拔地区部分幼虫不滞育,但种群数量较低。田间调查结果表明,亚洲玉米螟在德宏州分布较广,不同地区发生为害存在着显著性差异,发生严重地区亚洲玉米螟为害率最高可达97%,为害级别多为3~4级,集中分布于东经97°51′~97°60′区间,呈带状分布。亚洲玉米螟发生为害在不同经度上存在显著性差异,平均为害率和为害级别分别是57.75%和4级。在不同海拔和纬度之间亚洲玉米螟发生概率也存在显著差异,在901~1 100m和1 301~1 500m海拔和24°46′~25°59′纬度之间发生概率高。

Population dynamics and major damage region of Asian corn borer Ostrinia furnacalis in Dehong Prefecture of Yunnan Province

Population dynamics and major damage area of Asian corn borer (ACB),Ostrinia furnacalis (Guenée), were investigated in Dehong Prefecture of Yunnan Province by using sex pheromone traps and field survey.The results indicated that the population dynamics of ACB differed in terms of latitude.ACB occurred all year around in low altitude (<1 000 m)areas;while in high altitude (>1 200 m)areas,ACB occurred between April and Au-gust.There were 4 to 7 generations of ACB yearly in Dehong Prefecture,and the generations of ACB were over-lapped.ACB entered a winter diapause in the mature larvae in high altitude areas,while some larvae did not enter a diapause in low altitude areas in winter season with low ACB population.Field survey indicated that ACB dis-tributed widely in Dehong Prefecture.Maize damage caused by ACB differed significantly in different regions with different longitudes,with the average damage rate of 57.75% and damage level of grade 4.Serious damage on maize plants was commonly observed between east longitude 97°51′and 97°60′.There was no significant differ-ence in different altitude and latitude.Occurrence probabilities of ACB differed significantly at different altitude and latitude,and which were higher at 901-1 100 m,1 301-1 500 m and from 24°46′to 25°59′than other regions.