粘虫(Mythimna seperata)为害小麦的产量损失和幼虫密度及生育期的关系  

WHEAT YIELD LOSS IN RELATION TO DENSITY OF ARMYWORM(Mythimna seperata)LARVAE AND WHEAT DEVELOPMENT STAGE

作　　者：袁全昌[1] 余小兰[1] 

机构地区：[1]上海市农业科学院植物保护研究所,上海201106

出　　处：《上海农业学报》1993年第4期64-68,共5页Acta Agriculturae Shanghai

摘　　要：研究进一步确定了粘虫(Mythimna seperata)为害损失同幼虫密度和小麦生育期的关系。结果表明,在同样的幼虫密度下,生育期越晚,受害越轻。数据表明,临界受害期在5月10日前后,过了5月15日,即使全部叶片都受害,产量也不会受影响。本研究同时测定了各龄幼虫的食叶量和扬麦5号小麦的全株叶片面积,并根据上述结果分析推导出了包括幼虫数量和生育期在内的估计粘虫为害损失百分率的公式:DP=0.031L(71.23-1.480x),式中 DP=损失百分率,L=能发育到6龄并化蛹的幼虫数,X=从4月1日开始的日数。应用这个方程可很方便地估计不同时期不同幼虫数所造成的损失百分率。The relationship between wheat yield loss and armyworm larvae's density as well as wheat development stage was further investigated.The result showed that at the same density of larvae,the later the wheat devlopment stage the less the yield loss and the critical damaging stage was around May 15th,and thenceforth no yield loss was observed. The leaf consumption of larvae at different instars and the leaf area per wheat stem at different stages were determined and an equation for estimating percentage yield loss at dif- ferent development stages and larva densities was thus developed as DP=0.031L (71.23— 1.480X),where DP=percentage yield loss,L=density of larvae surviving to pupation,X= days beginning from April 1st,i.e.April 15th=15,May 15th=45.

关 键 词：粘虫 小麦 产量损失 密度 危害 

分 类 号：S435.122.9[农业科学—农业昆虫与害虫防治]