氧化乐果与敌敌畏乳油混剂防治华山松大小蠹试验报告

选择初侵染木作为防治对象,使用农药氧化乐果与敌敌畏乳油混剂(1),采取打孔注药法对华山松树体内大小蠹虫进行了防治试验.结果表明,施药浓度为30-35倍液,其杀虫率可达85%以上,防治效果较好.     

利用捕食性天敌大唼蜡甲防治大小蠹属害虫的研究进展

综述云杉大小蠹的重要捕食性天敌昆虫大唼蜡甲在国内外的研究、应用情况,对大唼蜡甲的生物学和习性、化学生态研究情况、人工大量饲养和储存方法进行详细介绍,并对法国、英国等国家运用大唼蜡甲防治云杉大小蠹的实践进行总结.根据其特性及近年来国际生物防治理论的新发展,以引入大唼蜡甲对已传入我国的重大外来入侵害虫--红脂大小蠹进行生物防治的成功实践为例,讨论引入大唼蜡甲防治其他针叶树大小蠹的可能性和必要条件以及应采取的策略.     

Response of bark beetles and their natural enemies to fire and fire surrogate treatments in mixed-conifer forests in western Montana

Four treatments (control, burn-only, thin-only, and thin-and-burn) were evaluated for their effects on bark beetle-caused mortality in both the short-term (one to four years) and the long-term (seven years) in mixed-conifer forests in western Montana, USA. In addition to assessing bark beetle responses to these treatments, we also measured natural enemy landing rates and resin flow of ponderosa pine (Pinus ponderosa) the season fire treatments were implemented. All bark beetles were present at low population levels (non-outbreak) for the duration of the study. Post-treatment mortality of trees due to bark beetles was lowest in the thin-only and control units and highest in the units receiving burns. Three tree-killing bark beetle species responded positively to fire treatments: Douglas-fir beetle (Dendroctonus pseudotsugae), pine engraver (Ips pini), and western pine beetle (Dendroctonus brevicomis). Red turpentine beetle (Dendroctonus valens) responded positively to fire treatments, but never caused mortality. Three fire damage variables tested (height of crown scorch, percent circumference of the tree bole scorched, or degree of ground char) were significant factors in predicting beetle attack on trees. Douglas-fir beetle and pine engraver responded rapidly to increased availability of resources (fire-damaged trees); however, successful attacks dropped rapidly once these resources were depleted. Movement to green trees by pine engraver was not observed in plots receiving fire treatments, or in thinned plots where slash supported substantial reproduction by this beetle. The fourth tree-killing beetle present at the site, the mountain pine beetle, did not exhibit responses to any treatment. Natural enemies generally arrived at trees the same time as host bark beetles. However, the landing rates of only one, Medetera spp., was affected by treatment. This predator responded positively to thinning treatments. This insect was present in very high numbers indicating a regulatory effect on beetles, at least in the short-term, in thinned stands. Resin flow decreased from June to August. However, resin flow was significantly higher in trees in August than in June in fire treatments. Increased flow in burned trees later in the season did not affect beetle attack success. Overall, responses by beetles to treatments were short-term and limited to fire-damaged trees. Expansions into green trees did not occur. This lack of spread was likely due to a combination of high tree vigor in residual stands and low background populations of bark beetles.     

茶藨生柱锈菌致病性分化的初步研究

采用交互接种的方法对华山松疱锈病、红松疱锈病的病原菌茶藨生柱锈菌的致病性分化进行了研究。结果表明:(1)红松疱锈病的病原菌锈孢子只能侵染其本地的转主寄主植物东北茶藨子;(2)华山松疱锈病的病原菌锈孢子能转主侵染多种不同地区的茶藨子植物;(3)所有华山松疱锈病病原菌的锈孢子均不能转主侵染东北茶藨子;(4)初步认定马先蒿属植物不是华山松疱锈病病原菌的转主寄主。     

不同发育阶段华山松林下药用植物多样性及其数量特征

对昆明西山幼林期和杆材林期两个不同发育阶段华山松林的药用植物多样性及其数量特征进行了研究。结果表明:不同发育阶段的药用植物主要优势种组成不一,其重要值也不同;在灌木层,华山松幼龄林优势种为火把果,杆材林期优势种为小铁子,幼龄期草本层优势种为土牛膝,而杆材林期优势种为小铁子。就药用植物多样性指数而言,杆材林期灌木层物种数及香农-威纳指数分别比幼龄期的大,而杆材林期的均匀度指数却比幼龄期的小;杆材林期草本层的物种数、香农-威纳指数及均匀度指数分别比幼龄期的大;表现出林下药用植物多样性指数随着林分年龄的增长而呈上升的趋势。     

油松挥发性物质分析及红脂大小蠹的触角电位反应

分布于山西的油松树脂中的挥发性物质主要成份为(R)-( )-α-蒎烯、(S)-(-)-β-蒎烯和(S)-( )-3-蒈烯,占萜烯总量的97%以上,其中(S)-( )-3-蒈烯的比例最大,另外还有香叶烯、( )-柠檬烯、莰烯、孟二烯和水芹烯等成份.触角电位反应中,雄性红脂大小蠹对油松挥发性物质中(S)-(-)-α-蒎烯、柠檬烯和(S)-( )-3-蒈烯的反应较为强烈,而雌性红脂大小蠹对油松挥发性物质中(S)-( )-3-蒈烯、柠檬烯、(S)-(-)-α-蒎烯和香叶烯的反应较为强烈.雌性红脂大小蠹较雄性红脂大小蠹对这些挥发性物质更为敏感.寄生于我国油松的红脂大小蠹对树体挥发物的反应与原产地美国有较大的差异,产生变化可能与寄主挥发物成分和环境变化有关,但其机制还有待于进一步研究.     

秦岭华山松小蠹消化道结构与食性分化的研究

对华山松小蠹的消化道结构及食性的对比分析表明,小蠹虫的消化道结构随食性的不同而发生相应的结构变化.取食木质部营养的小蠹虫,由于主要利用在寄主树木木质部组织内培养的茵类,导致其消化道结构简单,取食韧皮部组织的小蠹虫消化道结构复杂.同时,寄主树木抗性与小蠹虫消化道结构间存在密切的关系,寄主树木抗性越强,则小蠹虫中肠越长,以更加有效地抵御健康寄主树木抗性和利用寄主树木树脂等营养物质.小蠹虫前胃板结构也表现出食性的分化和变异,入侵木质部的小蠹前胃板板状部缩短,韧皮部小蠹前胃板骨化程度较大,且前胃板的复杂程度与消化     

我国三种大小蠹危害及其天敌昆虫应用

华山松大小蠹、红脂大小蠹和云杉大小蠹是危害中国松属的重要大小蠹属害虫,给森林生态系统带来极大破坏。华山松大小蠹是先锋型害虫,可直接危害健康华山松。红脂大小蠹和云杉大小蠹为检疫性害虫,主要危害衰弱木,有些情况下也可侵染健康木。由于大小蠹危害隐蔽,一经发现便已造成林木死亡,给森防工作带来极大困难。通过概述三种大小蠹的生物学习性,分析了入侵机制、适生性和风险评估情况,并在此基础上对三种大小蠹的天敌昆虫进行了统计和预估分析,可为进一步开发和利用天敌昆虫提供参考依据。     

华山松有害生物灾害经济损失初步研究

在毕节地区华山松害虫种类调查研究中,应用常国彬等提出的林业有害生物灾害经济损失评估计算方法,对赫章县水塘林场2004年生物灾害经济损失进行计算.结果:直接经济损失L直接667万元,间接经济损失L间接在4000万元到1.3亿元之间.     

华山松大小蠹对9种植物挥发物的EAG和行为反应

选取5种非寄主挥发性化合物水杨醛、壬醛、三氯乙烯、二氯甲基甲醚和顺-3-己烯-1醇,4种寄主挥发性化合物β-蒎烯、(+)-3-蒈烯、β-石竹烯和(+)-α-蒎烯,应用触角电位仪和Y型嗅觉仪初步研究了华山松大小蠹成虫对这9种化合物的EAG反应和趋向反应。结果表明:雌虫对三氯乙烯、(+)-3-蒈烯和β-石竹烯,雄虫对壬醛、二氯甲基甲醚、(+)-3-蒈烯和(+)-α-蒎烯有明显的EAG反应;β-蒎烯、(+)-3-蒈烯和(+)-α-蒎烯对华山松大小蠹雌成虫有较强的引诱作用;三氯乙烯对雄成虫有较高的引诱率,且显著高于对雌成虫的引诱率。试验结果可为华山松大小蠹的行为控制技术研究提供借鉴。