共查询到19条相似文献，搜索用时 687 毫秒
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萧氏松茎象幼虫食性、危害及防治技术 总被引：24，自引：2，他引：24
萧氏松茎象幼虫在南岳衡山主要危害华山松，在寄主树干基部皮层和裸露的根皮层蛀食，造成大量流脂，导致生长衰弱，引起松墨天牛暴发；同时取食新鲜松脂，越冬后的幼虫仅靠取食新鲜松脂就能正常发育。幼虫只危害健康松树，不危害衰弱木、枯立木，说明其蛀食危害与松树能否分泌松脂有关。在被害松林内，单株幼虫数在0～6头之间。幼虫在有虫株之问分布较均匀，1头／株的占82．5％，平均为1．38头／株，且单株虫口密度与树干基部直径呈明显正相关。混交林和非松树林分能阻止该虫扩散。5—10月间在幼虫危害期和蛹期，采用人工清除幼虫和蛹的方法可有效控制该虫危害，而采用化学药剂防治该幼虫，效果不明显。 相似文献
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松瘤象幼虫危害马尾松活立木，在渝北区1a发生1代，以幼虫在被害树木质部越冬。翌年5月上旬开始化蛹，下旬始见成虫，6月上旬为成虫羽化高峰期，中旬为产卵盛期，幼虫孵化后即危害马尾松活立木的韧皮部及木质部表层，以后逐渐向木质部危害。可利用成虫具有较强趋光性的特性，设灯诱杀成虫；幼虫危害期对受害木进行拔除销毁，可降低虫口密度；加强检疫，防治人为传播。 相似文献
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沙棘主要蛀干害虫危害特性及种群动态变化 总被引：4，自引：0，他引：4
沙棘木蠹蛾主要危害沙棘栽植树的根部和干部，红缘天牛同时危害沙棘栽植树和根蘖苗的干部，已成为宁夏沙棘林中两大主要蛀干害虫。通过对沙棘树不同高度范围内沙棘木蠹蛾幼虫和红缘天牛幼虫的调查发现，沙棘木蠹蛾幼虫主要分布在地下根部和干部40～120cm的范围内，而红缘天牛主要分布在树干40～120cm的高度内。红缘天牛幼虫数量随时间变化大致呈现向树干上部增加的变化趋势。沙棘木蠹蛾幼虫数量随时间变化呈现明显的向根部转移的趋势，7月末，有近98％的幼虫在根部危害。之后，由于初孵幼虫的大量出现，使干部幼虫数量急剧增加，越冬前，虽然有部分转移至根部危害，但到9月末仍有近43％的幼虫停留在树干40～120cm处越冬，直到次年越冬结束。沙棘木蠹蛾和红缘天牛在沙棘树干部40cm以上危害位置的较大重叠，必然造成它们在时间、空间和营养上的激烈竞争。 相似文献
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松毛虫可分为落叶松毛虫与油松毛虫，属于鳞翅目枯叶蛾科，主要危害落叶松、红松、樟子松等，老龄幼虫危害最为严重，特别是越冬后的幼虫，取食量大增，被害林木常常大片光秃以致枯死，给林业生产带来了严重的危害。 1生活史 落叶松毛虫与油松毛虫的生活史基本相似，大多 1年发生 1代，以 3～ 4龄幼虫在树干基部周围的枯枝落叶层下卷曲越冬。翌年春 4～ 5月，油松毛虫在日平均气温达到 5.7℃、落叶松毛虫在日平均气温达到 8～ 10℃时上树危害， 6月中旬结茧化蛹， 7月上旬开始羽化， 8月初出现秋代幼虫， 10月份下树越冬。 2… 相似文献
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柳厚壁瘿叶蜂是发生在甘肃天水柳树上的中国新记录种,1年1代,以老熟幼虫在表土中结茧越冬,成虫于3月下旬羽化,产卵于芽尖叶片组织内,4月上旬幼虫危害并形成虫瘿,至11月下旬以老熟幼虫入土结茧越冬。幼虫期采用树干注射14%吡虫啉.敌敌畏液剂和30%敌敌畏.氧化乐果液剂,防效可达95.0%~91.2%。 相似文献
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浅谈营林技术与天牛治理 总被引：2，自引：0，他引：2
天牛是危害我国杨、柳、榆等树种的重要蛀干害虫,由于其蛀干危害、生活隐蔽、防治难度大而成为树木毁灭性害虫,多年来一直制约着杨树等树种的栽植和发展.回顾多年来防治天牛的实践,采用营林技术来治理天牛,可以实现有效控制天牛危害. 相似文献
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Insect samples were collected from the canopy of 24 willow short rotation coppice (SRC) sites on farmland in Britain and Ireland in 1995. The blue willow beetle Phratora (= Phyllodecta) vulgatissima (L.) (Coleoptera: Chrysomelidae), previously identified as the main defoliating pest of this crop, was recorded from 13 of these at varying levels of abundance. Data describing aspects of the environment at each site were also collected. These data were used to create potential explanatory variables for a regression analysis of beetle abundance. This analysis indicated that P. vulgatissima were most likely to occur and were more abundant at older willow sites on clay soils and at sites that bad certain free-living willow species growing nearby. Within sites, most willow clones sampled contained P. vulgatissima, although two, Salix burjatica‘Germany’ (‘Aquatica Gigantea’) and Salix mollissima‘Q83’ (Salix triandra × Salix viminalis), were avoided. Chrysomelid pest avoidance and clonal resistance could form part of an integrated pest management strategy for SRC crops. 相似文献
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Many willow species (genus: Salix) co-occur within habitats (α-diversity) and across the landscape (β-diversity) throughout North America. This high diversity is challenging to explain because closely related species often share similar functional traits and thus experience heightened competition and shared pest and pathogen susceptibility. To investigate whether traits related to drought survival are important in maintaining diversity, we conducted an experimental dry-down on six willow species in a greenhouse. We compared species' growth rates, stem and leaf hydraulics, leaf function and dieback and examined potential associations between their drought responses and habitat affinities. Habitat affinities were characterized based on species occurrence in randomly established field plots in central Minnesota. Overall, species that occur in drier, more seasonally variable habitats tended to have higher water-use efficiency, and faster growth rates than species from wetter habitats. However, the greatest difference in drought survival strategies was found between two species with similar habitat affinities. We conclude that differences in willow species could be important in both driving habitat differentiation and permitting temporal differentiation in resource utilization within habitats. Therefore, species' water-use strategies could be important in maintaining both α- and β-diversity across the landscape. 相似文献
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目前,化学防治是我国林业害虫的主要防治手段,但造成了严重的环境污染,破坏了生态平衡。本文对物理机械防治方法和技术进行了系统的介绍,采用物理机械防治可避免生态环境的破坏,且能收到良好的效果,保持林业的健康发展。 相似文献