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Aproceros leucopoda has been found at nine locations in urban areas and in forests in the Czech Republic. Aproceros leucopoda was first reported at a location 700 m a.s.l. in the northern part of the country in 2011. The other locations range in elevation from 150 to 460 m a.s.l. In the current study, A. leucopoda was studied in four plots, where larvae and their zigzag feeding tracks were observed on 10 Ulmus trees located south of Lanžhot (southeastern Czech Republic) in 2014 and 2015. In 2014, feeding tracks and larvae were detected in late May, from 22 June to 13 July, and from 9 August to 6 September, suggesting the occurrence of three generations per year in the southeastern Czech Republic. The southern Czech Republic has been colonized much earlier than other parts of the country because of its proximity to localities with A. leucopoda in Slovakia and Austria. The presence of larvae or evidence of larval feeding was detected on only 2.84% of monitored leaves. We suggest that A. leucopoda endangers solitary elms in urban greening areas more than elms in forests.  相似文献   
2.
中国纽扁叶蜂属一新纪录种(膜翅目,扁叶蜂科)   总被引:1,自引:1,他引:1       下载免费PDF全文
本文记述纽扁叶蜂属中国一新纪录种——珍珠梅纽扁叶蜂Neurotoma sibirica Gussakovskij。其中卵、幼虫及蛹(浸渍标本)的形态均为首次记载。  相似文献   
3.
丝角叶蜂属一新种(膜翅目:叶蜂科)   总被引:1,自引:0,他引:1       下载免费PDF全文
本文记述叶蜂科、丝角叶蜂亚科一新种——杏丝角叶蜂Nematusprunivorous。本种在浙江省淳安县严重危害杏树。  相似文献   
4.
This study aimed to draw the attention of the all stake holders attention to an underestimated insect pest of wheat in Southeastern Anatolia. The field studies were carried out in the experimental field of GAP Training, Extension and Research Center in Koruklu in 2003–2004 cropping season.

It was found that the number of sawfly damaged spikes varied between 6 and 12% in durum wheat and 8 and 12% in bread wheat. Comparing healthy grains, grain weight spike−1 decreased significantly, giving 0.430 g less kernel weight in durum wheat and 0.385 g in bread wheat. Some of the grain quality characteristics of both sawfly damaged and healthy spikes were tested and it was found that protein content (%) in durum wheat, and 1000 kernel weight in bread wheat were reduced significantly, whilst, the SDS sedimentation value in bread wheat increased significantly for sawfly damaged grains. Grain yield losses by sawfly infestation were found to be 2.23% in durum wheat and 3.32% in bread wheat. Marketing price studies showed that sawfly damage reduced it significantly, resulting in $ 0.016 kg−1 less price in bread wheat. But this was not serious for durum wheat.

It was concluded that income loss, depending on grain yield loss, un-harvestable broken spikes and lower marketing price of sawfly damaged grains, could be no less than $ 68.8 ha−1 in durum wheat and $ 68.6 ha−1 for bread wheat. Therefore, some control methods are required for sawfly infestation, where damage is already over the economic threshold (10–15% stem cut by pest) especially in bread wheat.  相似文献   

5.
落叶松叶蜂生物学特性及防治方法的研究   总被引:4,自引:0,他引:4  
李惠成  王建中 《林业科学》1992,28(4):317-322
落叶松叶蜂是危害华北落叶松的重要害虫,在内蒙古乌兰察布盟地区一年发生一代,以预蛹在茧内越冬。林分郁闭度在0.6以上时,用烟雾剂0.75kg/mu防治2—3龄幼虫,效果达70.1—83.2%;25%灭幼脲Ⅲ号20—30g/mu低容量喷雾防治2—3龄幼虫,效果81.1—95.5%;人工搂树盘暴露越冬预蛹,效果95.9%。  相似文献   
6.
斯氏线虫CB—2Y品系对李实蜂的侵染试验   总被引:10,自引:0,他引:10  
刘奇志 《昆虫天敌》1993,15(2):84-87
李实蜂是李子果实的重要害虫。本文探讨了斯氏线虫 CB-2Y 品系对李实蜂幼虫、茧的室内及田间侵染力。结果表明:1.李实蜂幼虫对该线虫很敏感,96小时死亡率93.3%~100%,茧不敏感,死亡率0~6.2%。2.该线虫对李实蜂幼虫侵染力很强,幼虫死亡率随作用时间及剂量浓度增加而增高。3.该线虫侵染李实蜂的田间效果7天后死亡率为70%左右,18天后死亡率达75%以上。  相似文献   
7.
记述了我国主要森林害虫叶蜂类天敌姬蜂种类及其寄生特点、控制作用、研究现状,并对姬蜂的应用前景和研究方向进行了讨论。  相似文献   
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