甘薯小象甲发生特点调查与原因分析

Investigation and Analysis of the Occurrence Characteristics of Cylas formicarius

甘薯小象甲是福建省甘薯生长期和贮藏期的重要害虫,以幼虫蛀食薯蔓和薯块为主,该虫为害隐蔽,单一防治效果不理想,损失率一般为20%~30%,对翔安区甘薯生产为害极大。通过性诱剂监测甘薯小象甲田间虫口密度消长情况,分析了甘薯小象甲在翔安区的世代与越冬特性等发生特点,同时比较了不同农田类型及不同甘薯品种小象甲发生为害动态差异性。研究结果表明：甘薯小象甲在厦门市翔安区的发生特点为越冬基数旱地（138.56只/m2）大于水田（98.56只/m2）,越冬成虫中雌虫比例高于雄虫;株为害率旱地、农改地高于水田,分别为61.67%、48.33%、20%;为害高峰期为每年10—11月;主栽品种‘潮薯13’为害率高于‘配26’。

Cylas formicarius is an important insect pest during the growing and storage period of the sweetpotatoes in Fujian, the damage mainly caused by larva biting of the vines and potato chunks. Since the damagewas not obvious and the single control efficiency was not good, the loss ratio could be 20% to 30% and thedamage to the sweet potato production in Xiang＇an was serious. A research was made to analyze thecharacteristics of generations and overwintering of Cylas formicarius in Xiang＇an area after monitoring thegrowth and decline of Cylas formicarius in the field by using gyplure, and at the same time to compare thedynamic state differences of damage of different kinds of fields and Cylas formicarius. It showed that in Xiang＇anarea of Xiamen, the cardinality after wintering of Cylas formicarius in dry land（138.56 /m2） was bigger thanthat in paddy field（98.56 /m2）, and the percentage of female insects was higher than that of male insects amongthe imagoes after wintering; the ratio of damaged plants in dry land and farming changed field were higher thanthat in paddy field, with the percentage being 61.67%, 48.33% and 20%; the peak season of damage was fromOctober to November; the damage ratio of the main cultivar‘Chaoshu 13＇was higher than that of‘Pei 26＇.