摘要
森林食叶害虫的世代重叠会给防治造成巨大的困难。本文以杜仲梦尼夜蛾为研究对象,在灵宝市杜仲果园设立标准样地和样株,通过调查虫口密度,评估其危害,定期发布预警。经过2016-2017连续2年的研究发现,杜仲梦尼夜蛾世代重叠严重。2016年种群爆发,8月上旬叶面积损失率平均达21%,个别区域达100%;叶面积损失率与之前相隔20 d的虫口密度呈极显著的正相关关系。杜仲在5月初至6月初受害会严重影响果实正常发育,并造成种仁败育、果实提早脱落,最高落果率达50%。因此,5月初至6月中旬是杜仲梦尼夜蛾防治的最关键时期。2016年根据林间调查的虫口密度发布的短期预警,经叶面积损失率和落果率评判,准确率均在90%以上,说明短期预警具有良好可操作性。2017年将预警发布指标调整为株虫口密度≥3头/株,预警发布5 d内完成防治,并优先对发布灾害预警的区域开展防治。后期调查发现,在示范区和对照区,叶面积损失率均维持在1%以下。对世代重叠严重的食叶害虫,短期预警对及时采取应对措施可以起到关键作用。
Forest leaf-eating insect with generation overlap is difficult to control. In this paper,the damage to Eucommia ulmoides Oliver trees caused by Orthosia songi Chen et Zhang was assessed.Outbreaks of O. songi was forecasted periodically in 2016 and in 2017 through larval density survey in Eucommia orchard located in Lingbao,China. Results indicated that O. songi generation overlapped seriously. In 2016,the average leaf area loss rate was 21% or even 100% in some plots. The leaf area loss rate was significant positively related with larval density. Fruit growth was strongly affected by larval density from early May to Mid June; which the serious infestation caused seed abortion and pre-muture dropped. The highest fruit drop rate was over 50%. Therefore,the optimal time period for control ofO. songi was from early May to Mid June. Short term forecast in 2016 based on larval density was evaluated by leaf area loss rate and fruit drop rate. The over 90% accuracy of early warning suggested that short term forecast was operational for complementation of control activities. The warning index was adjusted to 3 larvae per tree in 2017. Control activities were carried out within 5 days strictly upon forecast,i. e. plantations prior to be controlled where larval density warning was released. Lower than1% of leaf area loss indicated the control was effective in both demonstrated plot and control area in2017. Our study revealed that short term forecast played a key role for control of the insect species with generation overlap life cycles.
作者
徐睿
刘慧东
朱景乐
殷世雨
杜红岩
孙志强
XU Rui;LIU Hui-Dong;ZHU Jing-Le;YIN Shi-Yu;DU Hong-Yan;SUN Zhi-Qiang(Henan Forestry Vocational College,Luoyang 471002,Henan Province,China;Paulownia RPD Center of China,CAF,Zhengzhou 450003,China;Eucommia Engineering Research Center of State Forestry Administration,Zhengzhou 450003,China;Xinyang Nanwan Experimental Forest Farm,Xinyang 464031,Henan Province,China)
出处
《环境昆虫学报》
CSCD
北大核心
2018年第3期593-600,共8页
Journal of Environmental Entomology
基金
国家林业公益性行业科研专项(201304406)
关键词
杜仲梦尼夜蛾
世代重叠
虫口密度
短期预警
杜仲果园化栽培
叶面积损失率
Orthosia songi Chen et Zhang
generation overlap
larval density
short term forecast
Eucommia ulmoides orchard
leaf area loss rate
