Aerially applied methylcyclohexenone-releasing flakes protect Pseudotsuga menziesii stands from attack by Dendroctonus pseudotsugae

We tested methylcyclohexenone (MCH), an anti-aggregation pheromone for the Douglas-fir beetle (Dendroctonus pseudotsugae), for protection of Douglas-fir (Pseudotsuga menziesii) stands by applying MCH-releasing polymer flakes by helicopter twice during summer 2006 to five 4.05-ha plots in the State of Washington, USA. Five similar plots served as untreated controls. We assessed D. pseudotsugae flight into study plots using baited pheromone traps, and tallied D. pseudotsugae attack rates on all P. menziesii trees in 2005 and 2006. We also measured stand basal area and incorporated that as an explanatory variable in the analysis. Significantly fewer D. pseudotsugae were trapped in treated plots than in control plots, and significantly fewer P. menziesii trees were attacked in treated plots than in control plots. The attack rate in untreated stands was nearly 10 times that of treated plots, and stands with higher basal area were significantly more likely to be attacked by D. pseudotsugae than were stands of lower basal area. Attack rates in 2006 and 2005 were significantly correlated, regardless of treatment.     

信息化合物对西花蓟马的行为调控及其应用

西花蓟马(Frankliniella occidentalis)是一种危险性的外来入侵害虫,其寄主范围广、繁殖速度快、抗药性强、防治难度大,在我国发生后对蔬菜、花卉等经济作物造成了严重的损害。信息化合物在昆虫与植物或昆虫与昆虫之间的化学联系中起着决定性的作用,它调控着昆虫的多种行为。本文主要综述了植物挥发性物质及昆虫信息素对西花蓟马的行为调控及其在防治中的应用研究进展。     

Protection of spruce from colonization by the bark beetle, Ips perturbatus, in Alaska

Field bioassays were conducted in south-central Alaska in a stand of Lutz spruce, Picea × lutzii, to determine whether a semiochemical interruptant (verbenone and trans-conophthorin) and/or a defense-inducing plant hormone (methyl jasmonate, MJ) could be used to protect individual standing trees from bark beetle attack. During two experiments (initiated in May 2004 and 2005, respectively), attacks by Ips perturbatus on standing trees were induced by using a three-component aggregation pheromone (ipsenol, cis-verbenol, and ipsdienol) and prevented by using the interruptant. In 2005, treatments from 2004 were repeated and additional treatments were evaluated by using MJ spray or injection with and without the interruptant. Aggregation began before 3 or 7 June, and attack density was monitored through 3 or 16 August. During both years, tree mortality caused by I. perturbatus was recorded twice (in August, and in May of the following year). In both experiments, attack density was greatest on trees baited with the three-component attractive pheromone, but was significantly reduced by addition of the semiochemical interruptant to trees baited with the attractant. There were no significant differences in attack density between attractant + interruptant-treated trees and unbaited trees. In 2004, mortality was highest among attractant-baited trees, whereas addition of the interruptant significantly reduced the level of initial (10 week post-treatment) and final (54 week post-treatment) mortality. In 2005, no significant reduction in attack density occurred on trees baited with the attractant when MJ was sprayed or injected. The highest initial (10.6 week post-treatment) and final (49.4 week post-treatment) mortality was observed among trees that had been injected with MJ and baited with the attractant. Mortality at the final assessment was significantly lower in all other treatment groups. As in 2004, addition of the interruptant to attractant-baited trees significantly reduced the level of final mortality compared to attractant-baited trees. MJ was not attractive or interruptive to I. perturbatus or associated bark beetles in a flight trapping study. However, MJ-treated trees (sprayed or injected) exuded copious amounts of resin on the bark surface. Anatomical analyses of felled trees from four treatment groups [Tween (solvent)-sprayed, MJ-sprayed, Tween-injected, and MJ-injected + attractant baited] showed that treatment with MJ increased the number and size of resin ducts produced following treatment. These analyses also revealed a reduction in radial growth in MJ-treated trees. Our results show that during both years, treatment with a simple, two-component interruptant system of verbenone and trans-conophthorin significantly reduced I. perturbatus attack density and tree mortality on attractant-baited trees and provided a full year of protection from bark beetle attack.     

华山松大小蠹化学信息物质

在常温下(25℃)解剖华山松大小蠹(Dendroctonus armandi Tsai et Li)的雌、雄虫,以正己烷为溶剂提取华山松大小蠹的后肠和粪便挥发物,并进行GC-MS分析。结果表明:在室温状态下,雌虫后肠挥发物中含有23种物质,主要为萜酸类、萜烯类、雌雄甾类、醇类和醛类等;雄虫后肠中有25种,以有机酸(树脂型萜酸居多)、酯类化合物和萜烯类化合物为其主要成分;粪便中有33种,树脂型的萜酸最多。华山松大小蠹的化学活性物质以萜类化合物为主。     

寄主树木、小蠹与天敌三重营养关系的化学生态学研究进展

综述了寄主植物、小蠹、天敌三重营养关系的化学生态学研究。重点阐述了三方面:①信息化合物的来源及基本特性;②信息化合物在小蠹选择寄主行为过程中的作用;③信息化合物对天敌选择寄主行为的影响。④对寄主植物、小蠹和天敌三重营养关系的全面了解,将为小蠹的综合治理提供新思维。     

A pheromone trap monitoring system for the saddle gall midge,Haplodiplosis marginata (von Roser) (Diptera: Cecidomyiidae)

Outbreaks of saddle gall midge, Haplodiplosis marginata (von Roser) (Diptera: Cecidomyiidae) have been reported in Belgium and other European countries since 2010. Because of the sporadic nature of this pest, which can sometimes be very harmful to cereal crops, an effective monitoring tool is required, both to determine the optimal timing for insecticide applications, and to understand the enigmatic population dynamics of this insect. Following the recent identification of the major sex pheromone component of the saddle gall midge, non-2-yl butanoate, a slow-release dispenser was developed using rubber septa. The release rates of 5 mg and 10 mg-loaded dispensers were initially measured under laboratory conditions, and their effectiveness in terms of pheromone loading and use duration was assessed in the field. The experiments showed that sticky traps baited with 5 mg pheromone-loaded rubber dispensers, renewed every 6 weeks, are suitable for accurately monitoring male H. marginata flights.     

Aerially applied verbenone-releasing laminated flakes protect Pinus contorta stands from attack by Dendroctonus ponderosae in California and Idaho

We tested a new formulation of verbenone, an antiaggregation pheromone of the mountain pine beetle (Dendroctonus ponderosae Hopkins) (Coleoptera: Curculionidae: Scolytinae), for area-wide protection of lodgepole pine (Pinus contorta Douglas ex Loudon) stands in the western United States. Helicopter applications of verbenone-releasing laminated flakes were made at the rate of 370 g of active ingredient/ha to two sites, one in California and one in Idaho, during summer 2005. Each site consisted of five 20.23-ha treated plots and five matching 20.23-ha untreated plots. We assessed D. ponderosae flight into study plots using traps baited with aggregation pheromones and we tallied D. ponderosae attack rates on P. contorta trees in treated and control plots before and after application. There were no significant differences between numbers of D. ponderosae trapped on treated and control plots. However, a significantly smaller proportion of P. contorta trees was attacked in treated plots than in control plots at both sites; the attack rate in untreated stands was roughly three times that of treated stands in both California and Idaho, even at this low application rate. Furthermore, attack rate in 2004 was a significant explanatory variable for the response in 2005 regardless of treatment in both California and Idaho. There was no significant treatment effect at either site on attraction of Temnochila chlorodia (Coleoptera: Trogositidae) Mannerheim, a key predator of D. ponderosae, to the prey aggregation pheromone.     

寄主树木、小蠹与天敌三重营养关系的化学生态学研究进展

综述了寄主植物、小蠹、天敌三重营养关系的化学生态学研究。重点阐述了三方面：①信息化合物的来源及基本特性;②信息化合物在小蠹选择寄主行为过程中的作用;③信息化合物对天敌选择寄主行为的影响。④对寄主植物、小蠹和天敌三重营养关系的全面了解,将为小蠹的综合治理提供新思维。     

松纵坑切梢小蠹信息化学物质野外诱集效果试验

为了研究信息化学物质对松纵坑切梢小蠹的林间引诱活性，探讨用信息化学物质防治与监测松纵坑切梢小蠹的方法，2002年利用从加拿大引进的人工合成缓释性聚集信息化合物诱芯以及Lindgren漏斗式诱捕器，在长春市净月潭林场进行了信息化学物质的诱集效果试验。结果表明，供试的5种α-蒎烯同分异构体中有4种对松纵坑切梢小蠹有明显的引诱效果，其中(5％ ／95％-)α-蒎烯的诱集效果极显著地高于其它几种同分异构体。同时试验了3种信息化学物质壬醛(NL)、桃金娘烯醇(ML)和反式马鞭草烯醇(TV)对(5％ ／95％-)α-蒎烯的诱集增效作用，试验结果表明，壬醛(NL)和反式马鞭草烯醇(TV)的组合对(5％ ／95％-)α-蒎烯的增效作用极显著。