| 摘要: |
| 研究通过室内饲养和实地调查相结合的方法，掌握了广东地区樟巢螟（Orthaga achatina）的形态特征和发生及为害规律；并通过室内生测的方法，筛选出了防治樟巢螟幼虫的高效低毒药剂。主要研究结果如下：樟巢螟幼虫体棕黑色，中胸至腹末背面有1 条灰黄色宽带。成虫全身灰褐色，后翅棕灰色，雌雄成虫主要形态区别在于雄虫头部两触角间着生1~2 束向后伸展的锤状毛束。樟巢螟在广东省1年发生2 代，以幼虫群集筑巢啃食叶片。在广东省的寄主植物主要包括樟（Cinnamomun camphora）、肉桂（Cinnamomun cassia）、山胡椒（Lindera gluauca）、山苍子（Litsea cubeba）等，其中以香樟受害最为严重。不同浓度氯虫苯甲酰胺悬浮剂、毒死蜱乳油、马拉硫磷乳油对樟巢螟2~3 龄幼虫的毒力测定结果表明，毒死蜱100 倍稀释液处理24 h 后幼虫死亡率达100%，氯虫苯甲酰胺500 倍和马拉硫磷250 倍稀释液处理组24 h 的死亡率分别为55% 和80%，48 h 的死亡率分别为100% 和90%。毒死蜱1 000 倍稀释液对樟巢螟的LT50 最小，仅为12.6 h，击倒速度最快；其次为马拉硫磷250 倍稀释液，LT50 为15.8 h，氯虫苯甲酰胺的击倒速率相对毒死蜱和马拉硫磷较慢。综合防效和价格成本等因，70% 马拉硫磷乳油不仅成本较低，而且对樟巢螟幼虫的综合防效和毒死蜱相当，因此建议选择70% 马拉硫磷稀释250 倍用于林间防治樟巢螟幼虫。 |
| 关键词: 林业害虫 化学防治 樟科 触杀活性 生态保护 |
| DOI： |
| 投稿时间：2018-04-19修订日期：2018-05-12 |
| 基金项目:广东省林业科技创新专项（0835-1703228N2021)；广东省地方标准制（修）订林业项目 (2016-DB-02)。 |
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| The Biological Characteristics of Orthaga achatina and Screening of Contact Insecticides for Its Management |
| Li tinglu,Qin changsheng,Zhao danyang,Xu jinzhu,Yang hua,Jie yuze,Qiu Hua Long |
| (Forestry Pest Control and Quarantine Management Office of Guangdong Province;Guangdong Provincial Key Laboratory of Silviculture, Protection and Utilization/Guangdong academy of forestry) |
| Abstract: |
| In this study, morphological characteristics, occurrence and damage rule of Orthaga achatina were researched based on combination of insect indoor breeding and field surveys. High efficiency and low toxicity chemical pesticides were screened for the control of O. achatina larvae with normal bioassay method. The main results are as follows. larvae are brownish black, there is a broad band with grayish yellow color from the mesothorax to the end of abdomen in a dorsal view. The whole body color of adult is taupe, and the hind wings are brownish gray. The main morphological difference between male and female adults lies in the hammerlike hairs between two antennae on the head of male. There are two generations in a year of O. achatina in Guangdong province, larvae aggregate together to form a nest to damage the leaf. The hosts of O. achatina include Cinnamomum camphora, C. cassia, Lindera glauca and Litsea cubeba et al., in which C. camphora is injured most seriously. The results of contact toxicity of Chlorantraniliprole suspension, Chlorpyrifos EC and Malathion EC with various concentrations to 2~3 larvae of O. achatina showed that the mortality of larvae was 100% after 24 h with 100 times dilution of chlorpyrifos treatment, while the mortality in the 250 times dilution of Chlorantraniliprole and 500 times dilution of Malathion were 55% and 80%, respectively and then reached 100% and 90%, respectively, after 48h of treatment. The LT50 value of 1 000 times dilution of Chlorpyrifos against O. achatina larvae was 12.6 h, which is the lowest than that in other treatment, indicating its fastest knockdown speed against O. achatina larvae. The LT50 value was followed by 15.8 h in 250 times Malathion dilution treatment. Knockdown speed of Chlorantraniliprole is relative slower than that of Chlorpyrifos and Malathion. Take the control effects and prices into account together, 70% Malathion EC is not only cheaper in cost, but also have an approximate control effect with Chlorpyrifos. Therefore, we suggest that 250 times dilution of 70% Malathion EC could be used for management of O. achatina larvae in forest. |
| Key words: forest pests pesticide control Lauraceae toxicity activity ecological protection |
