摘要
甜菜夜蛾是我国严重为害蔬菜的害虫之一,本文测定了粘质沙雷氏菌菌株PS-1对甜菜夜蛾的致病力及其试验种群增长的抑制作用.用菌株PS-1菌悬液与人工饲料混配饲喂甜菜夜蛾2龄幼虫48 h,对其幼虫的存活有明显的抑制作用,对其蛹和成虫有明显的后致死作用.在2×10^1～2×10^8 cfu/g的浓度范围内,有明显的浓度效应.随着处理浓度的升高,甜菜夜蛾幼虫的死亡率明显提高,蛹的存活率明显降低,成虫产卵量明显减少,其试验种群的增长分别比对照降低了74.4％～100％.用浓度为1×10^3、1×10^5和1×10^7 cfu/mL的PS-1菌悬液分别配制成10％蜂蜜水饲喂甜菜夜蛾成虫2d,各浓度处理组成虫的寿命分别比对照缩短了5.70、5.91和7.16d,产卵量也明显减少.用浓度为1×10^9cfu/mL的PS-1菌悬液离心后,取上清液加入到人工饲料中饲喂甜菜夜蛾2龄幼虫48 h,幼虫8d累积死亡率达70.0％,显著高于对照.用组建生命表的方法评价了菌株PS-1对甜菜夜蛾的全面作用,该菌株对甜菜夜蛾试验种群增长的抑制作用,主要是其抑制了甜菜夜蛾幼虫和成虫的存活率以及成虫的生殖力.这些结果为甜菜夜蛾的生物防治和粘质沙雷氏菌PS-1的进一步开发利用提供了依据.
The beet armyworm, Spodoptera exigua, is one of the serious vegetable pests in China. In this study, toxicity of virulent Serratia marcescens isolate PS-1 originating from the larvae of Phyllotreta striolata were determined against S. exigua under laboratory conditions. The second instars ofS. exigua were fed for 48 h with an artificial diet which had been dipped in a suspension culture of PS-1. The treated larvae exhibited mortality in a dose dependent manner. Larval mortality significantly increased with increase in PS-1 concentration in the range of 2 ×10^1-2 ×10^8 cfu/g, and pupal survival and adult fecundity showed obvious decrease. Population growth orS. exigua was decreased by 74.4%-100% compared to the control. When S. exigua adults were fed for 2 d with honey solutions containing PS-1 at 1 ×10^3, 1 ×10^5 and 1 ×10^7cfu/mL, longevity of treated adults decreased by 5.70, 5.91 and 7.16 d, respectively, and fecundity was significantly reduced. When the artificial diet was dipped in supernatants of PS-1 suspension cultures （1×10^9cfu/mL） and used for the second instars for 48 h, larval mortality reached 70% in 8 days, which was higher than that in the control. Life table analysis demonstrated that PS-1 had a strong toxic effect on larvae and adults of S. exigua. These results show that S. marcescens PS-1 is a potential biocontrol agent against S. exigua.
出处
《中国生物防治学报》
CSCD
北大核心
2015年第4期501-507,共7页
Chinese Journal of Biological Control
基金
国家科技支撑计划(2012BAD19B0107)
