几种木材小蠹幼虫的鉴别

从香港进口木材检疫中,常发现成虫、幼虫同居一室,也有幼虫单独出现。目前国内资料报道的小蠹多为成虫,极少报道幼虫,而幼虫在昆虫学上是一个重要虫态,有必要对小蠹幼虫的形态特征进行探讨。本文着重描述八种木材小蠹幼虫的主要特征。     

进境木材的有害生物幼虫截获风险分析

[目的]我国每年进口大量木材,引起了外来有害生物的传入,其中包含种类繁多的检疫性有害生物幼虫,由于形态特征不明显,难以准确鉴定,增加了我国口岸进境木材的疫情防控压力.摸清由进境木材截获的有害生物幼虫的发生危害特点,并对检疫鉴定手段进行分析,可对进境木材的检疫工作提供参考,有效降低外来有害生物的传入风险.[方法]通过对全国口岸进境木材总体情况和有害生物幼虫危害情况的调查,并结合现有的各种检疫鉴定方法分析.[结果]进境木材数量稳中有升,携带外来有害生物幼虫数量不断增多.由于有害生物幼虫特征不典型,传统的形态学鉴定方法存在一定局限性,完善发展有害生物分子检测技术是我国进出境植物检疫工作的重点内容之一.[结论]研究结果可为有害生物幼虫的检疫鉴定和防控提供参考.     

日本在输入木材中截获的小蠹虫类

日本横滨植物防疫所调查研究部害虫课,早濑猛将1960～1979年20年间输入木材检疫截获小蠹科及长蠹科成虫标本,经有关人员鉴定确认者,件数多的苏联输入木材(日本称北洋材)小蠹13种218件,东南亚输入木材(日本称南洋材)小蠹8种432件,美国输入木材小蠹虫24种553件,按月分别集中统计其截获频度图型可分为3个类型。     

小蠹虫的检疫问题

随着我国经济建设速度的加快,木材的进口量会与日俱增,木材检疫工作也应予以特别重视。在木材检疫中,有关虫害问题最重要的应是小蠹虫了。原因是小蠹虫发生的机率大,虫体细小,种类繁多,不易鉴定。依照笔者所了解的各口岸近十来年的检疫情况,总地说来,在小蠹虫问题上存在着这样两种情况:一是按照检疫名单,从未放进过     

云南昭通蜜柑大实蝇和橘大实蝇的DNA条形码鉴定

蜜柑大实蝇(Bactrocera tsuneonis)和橘大实蝇(Bactrocera minax)属果实蝇属(Bactrocera)大实蝇亚属(Tetradacus),是为害柑橘类作物的两种检疫性实蝇。两种实蝇为近似种,仅成虫可通过形态特征进行鉴定,幼虫等非成虫虫态需采用分子生物学技术才能实现快速、准确的鉴定。本研究对采自云南省昭通市大关县、彝良县和永善县的大实蝇成虫及幼虫样品分别进行了形态鉴定和DNA条形码鉴定。结果表明,通过形态特征的对比以及DNA条形码序列的测定、比对和分析,采自大关县和彝良县的20头成虫样品分别为蜜柑大实蝇和橘大实蝇,采自彝良县和永善县的20头幼虫样品均为橘大实蝇。本研究实现了云南昭通地区两种大实蝇的DNA条形码鉴定,为我国植物检疫相关部门提供实用技术及决策支持。     

水浸处理原木杀虫效果的研究

对水浸处理原木杀灭木材中的松褐天牛、横坑切梢小蠹、材小蠹及病害松材线虫的效果进行了研究。结果表明天牛成虫、蛹及小蠹虫较易死亡，而天牛幼虫和松材线虫抗逆性强，需长时间浸泡。结论认为水浸处理原木需1年时间或在高温季节处理3个月才能达到检疫杀虫的目的。     

小蠹虫鉴定卡的制作

随着进口木材量的增加,人们对其所携带的害虫越来越关注。对木材危害最大,数量最多,种类最广的小蠹虫也越来越被科学工作者所重视。笔者通过几年的木材检疫工作的实践,试着将小蠹虫标本制成鉴定卡形式,使用起来准确、方便、现把方法总结如下,以供同行指正。     

澳洲大蠊二种同工酶谱及胆碱酯酶活性的研究

本文采用聚丙烯酰胺凝胶盘状电泳研究澳洲大蠊三个发育阶段酯酶同工酶，过氧化物酶同工酶谱的变化，并分别测定了发育三阶段和成虫头、胸、腹、脚胆碱脂酶活性。结果发现过化物酶同工酶与酯酶同工酶酶谱各有特征，从卵到二龄幼虫发育过程中表现最大活性的同工酶的酶带位置各不相同，胆碱酯酶活性在卵、一龄、二龄幼虫中以一龄幼虫活性最高，成虫中以头部活性最高，腹部活性最小。     

发生在葡萄上的蠹虫种类及成虫分类检索表

对采自全国的6种葡萄上钻蛀性蠹虫类害虫（2种小蠹和4种长蠹）成虫的形态进行了描述,根据其鉴别特征制作了成虫分类检索表,为葡萄蠹虫类害虫的识别和防治提供参考。     

吉林局首次截获断纹尼虎天牛

20 0 1年 4月 1 6日 ,吉林检验检疫局检疫人员对来自美国的红橡木单板及木托盘实施检疫时 ,发现木托盘一块木板上蛀道密布 ,斧劈检查发现 1种天牛成虫和活幼虫。经吉林省林业科学院专家初步鉴定 ,认为我国无此种天牛 ,后经国家总局动植物检疫实验所张生芳、陈乃中专家鉴定为断纹尼虎天牛Ｎｅｏｃｌｙｔｕｓｃａｐｒｅａ (Ｓａｙ)。本文对断纹尼虎天牛的有关资料进行了翻译和整理 ,并对其危害进行了分析 ,供检验检疫鉴定参考。1　形态特征成虫 :体长形 ,略粗壮 ;表皮黑色 ,附肢有时略带红色 ;前胸背板前缘有一条由密集白色柔毛组成的带 ,常在…     

Effect of log seasonality on reproductive potential ofMonochamus galloprovincialis reared in scots pine logs under laboratory conditions

Insect reproduction may be affected by a number of factors including seasonal changes in larval or adult nutrition. The effect of season on the reproductive potential ofMonochamus galloprovincialis (Olivier) females reared inPinus sylvestris L. (Scots pine) logs was investigated by constructing fertility tables for each log that differed only in the season they were cut. Population parameters were compared among three seasonal cohorts. The intrinsic rate of increase and most of the associated population parameters of beetles that emerged from logs cut during spring were higher than for beetles emerged from summer and autumn logs. Slight differences were found between summer and autumn cohorts. We suggest that seasonal differences in the nutritional quality of logs caused differences inM. galloprovincialis survival and reproductive potential. http://www.phytoparasitica.org posting March 16, 2008.     

A two-year study of parasitoid entomofauna associated with spruce bark beetles (Coleoptera: Curculionidae) in the altimontane belt of Slovenia (Pohorje)

Parasitoids are known to be an important factor in the population density regulation of bark beetles. In our study of the parasitoid complex of spruce bark beetles in 2011 and 2012, we collected bark samples from trees infested with I. typographus from spruce stands in the altimontane belt of Slovenia. The samples were taken at different altitudes: 450, 700 and 1230 m above sea level. A total of 9 bark beetle species and 12 parasitoid species was found. Ips typographus was most abundant, with 93% of all species of scolytids. The parasitoid species that were found belonged mainly to the Pteromalidae and Braconidae families. By far the most abundant and frequent species was Roptrocerus xylophagorum, which represented 84% of all parasitoids and was present in all study samples. Differences in species composition, parasitoid species diversity, species abundance and parasitism rate were confirmed between locations and also between both years of our study.     

Metabolism of juvenile hormone I by microsomal oxidase,esterase, and epoxide hydrase of Musca domestica and some comparisons with Phormia regina and Sarcophaga bullata

House fly (Musca domestica L.) microsomes prepared from larvae, pupae, or adults contain three enzyme system which can metabolize juvenile hormone I: an esterase, an oxidase, and epoxide hydrase. The presence of the oxidase is indicated by the increased metabolism when microsomes are supplemented with NADPH and by the occurrence of additional metabolites tentatively identified as products arising from oxidation of the 6, 7 double bond. Additional evidence of the activity of the oxidase system is the increased metabolism of juvenile hormone I by the NADPH-dependent system from phenobarbital-induced insects, by inhibition of the oxidation by piperonyl butoxide and carbon monoxide, and by the greater metabolism of the hormone by microsomes from insecticide-resistant (high oxidase) strains. In vivo studies of house fly adults treated with ³H-labeled juvenile hormone I reveal a pattern of metabolism similar to that seen during NADPH-supplemented in vitro metabolism. The three enzymes have somewhat different patterns of activity during the larval stage of the house fly, juvenile hormone esterase and epoxide hydrase beginning at a high level of activity in the young larvae while the juvenile hormone oxidase is low at this stage. In the late larval stage all three enzymes show increased activity followed by declines during the pupal stage and further increases in the adult stage. Comparison of in vitro enzyme levels of the house fly, flesh fly (Sarcophaga bullata Parker), and blow fly [Phormia regina (Meigen)] showed that, although the enzymes were present in the latter two species, their activity on a per insect basis was considerably less than that of the house fly.     

Daily consumption and predation rate of different<Emphasis Type="Italic">Stethorus punctillum</Emphasis> instars feeding on<Emphasis Type="Italic">Tetranychus urticae</Emphasis>

Laboratory experiments were conducted to evaluate the prey stage preference and the daily consumption of each stage of the coccinellid predatorStethorus punctillum Weise (Coleoptera: Coccinellidae) feeding on the two-spotted spider miteTetranychus urticae (Koch) (Acari: Tetranychidae). Groups of different life stages of the prey were offered (eggs, larvae, nymphs and adults). The prey preference varied with the stage ofS. punctillum. First larval instars had no significant preference among theT. urticae stages offered. Second larval instars consumed significantly more spider mite larvae in comparison with nymphs. In contrast, third larval instars indicated a strong preference for mite eggs. Significantly fewerT. urticae larvae were consumed by the fourth larval instars ofS. punctillum, in comparison with the three other mite stages. Finally, adult predators consumed significantly more mite eggs than the other stages offered. This preferential trend was similar for all adults tested, whether during the pre-oviposition or the oviposition period. http://www.phytoparasitica.org posting Feb. 17, 2004.     

Reduced viability of Colorado potato beetle, Leptinotarsa decemlineata, eggs exposed to novaluron

BACKGROUND: Novaluron is a benzoylphenyl urea chitin synthesis inhibitor that combines good activity against larval stages of the Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae), with low mammalian toxicity. Previous studies suggest that it has deleterious sublethal effects on adults. RESULTS: Continuous exposure of adult Colorado potato beetles to novaluron-treated foliage as both ovipositional and feeding substrate did not affect their survivorship or the number of eggs produced, but viable larvae hatched only from the eggs that were laid on the first day of the experiment. Viability was restored after adult beetles spent 48-96 hours on untreated leaves. In a separate experiment, direct exposure to novaluron of eggs laid by unexposed beetles also reduced the number of larvae hatching. CONCLUSIONS: Results confirm a negative effect of novaluron on the number of progeny produced by the Colorado potato beetle. Direct toxicity did not explain all of the reduction in egg hatch observed, suggesting that novaluron probably acted on reproductive adults as well as on eggs after they were deposited.     

New occurrence of Ips duplicatus Sahlberg in Herstal (Liege, Belgium)

The double-spined spruce engraver Ips duplicatus is not present in Belgium and France. In summer 2003, several adult Ips duplicatus beetles were caught near quays in Herstal (Liege) during a survey. Large volumes of spruce logs, from Russia and the Baltic countries, had been imported to the immediate locality where the beetles had been caught. Thus, it is most likely that the capture specimens were introduced with these consignments.     

Proteolytic enzymes secreted by larval stage of the parasitic nematode Trichinella spiralis

Excretory/secretory products (ES), collected from in vitro cultures of muscle larvae (L1) of Trichinella spiralis (Owen, 1835) were examined for the presence of proteolytic enzymes. Several discrete proteinases in the size range of 25-55 kDa were identified by substrate gel electrophoresis and were characterised according to pH optima, substrate specificity and inhibitor sensitivity using azocasein assay. Serine, cysteine and metalloproteinases active at pH 5-7 were identified. The serine proteinases were found to predominate and some of them were found to be specific for the larval stage of the parasite. The results from the substrate analysis indicated the presence of collagenolytic and elastolytic activities. The proteinase activity was inhibited by IgG isolated from T. spiralis-infected mice, an observation of relevance to understanding host/parasite interactions and, ultimately, the development of anti-Trichinella vaccine.     

Beetles (Coleoptera) caught with pheromones of Gnathotrichus retusus and G. sulcatus (Col., Scolytidae) in southern Finland

The ambrosia beetle Gnathotrichus materiarius, which originally came from North America, was discovered in southern Finland in 1996. In 1997, using Norwegian drainpipe traps baited with pheromones of Gnathotrichus retusus and G. sulcatus, we collected beetles in the region where the first specimen had been caught in order to determine whether this potential pest species had become established in the area. Samples from a total of 16 traps included 79 species of beetles and 719 individuals, but no specimens of G. materiarius. The most abundant species in the samples were the ambrosia beetles Xyleborus dispar and Trypodendron lineatum. Several predators and other associates of bark beetles were also captured. The majority of the beetles caught were saproxylic species.     

Beetles (Coleoptera) caught with pheromones of Gnathotrichus retusus and G. sulcatus (Col., Scolytidae) in southern Finland

The ambrosia beetle Gnathotrichus materiarius, which originally came from North America, was discovered in southern Finland in 1996. In 1997, using Norwegian drainpipe traps baited with pheromones of Gnathotrichus retusus and G. sulcatus, we collected beetles in the region where the first specimen had been caught in order to determine whether this potential pest species had become established in the area. Samples from a total of 16 traps included 79 species of beetles and 719 individuals, but no specimens of G. materiarius. The most abundant species in the samples were the ambrosia beetles Xyleborus dispar and Trypodendron lineatum. Several predators and other associates of bark beetles were also captured. The majority of the beetles caught were saproxylic species.