杨大透翅蛾习性观察及防治试验

杨大透翅蛾(Aegeria apiformis Cl.)属鳞翅目、透翅蛾科。是陕西省榆林地区危害杨树极为严重的一种蛀干害虫。为了掌握其发生规律,迅速解决防治问题,近年来我们调查了它的危害情况,定位观察了生活习性,并进行了防治试验。现将初步研究结果报告于下。     

白蜡吉丁虫肿腿蜂对三种蛀干害虫的寄生效能研究

利用白杨透翅蛾Paranthrene tabaniformis、杨十斑吉丁虫Melanophila picta和纳曼干脊虎天牛Xylotrechus namanganensis幼虫作为替代寄主对天敌昆虫白蜡吉丁虫肿腿蜂Sclerodermus pupariae进行人工饲养，成功繁殖出了成蜂。人工繁蜂的条件为：温度26℃，相对湿度70%，接蜂的蜂虫比3:1，三种替代寄主白杨透翅蛾、杨十斑吉丁虫和纳曼干脊虎天牛幼虫的被寄生率分别为43.77%、87.12%和82.41%；平均繁蜂时间分别为42 d、33.17 d和34.58 d；白杨透翅蛾、杨十斑吉丁虫和纳曼干脊虎天牛单个幼虫平均繁殖白蜡吉丁肿腿蜂分别为4083头、9033头和5092头；子代蜂的雌性率分别为9553%、9670%和94.57%。在7℃，相对湿度70%的条件下储藏，白蜡吉丁肿腿蜂子代成蜂的平均寿命150 d；寿命超过一个月的雌蜂占95%，雄蜂寿命5-7 d。     

吉林省杨树蛀干害虫的三种姬小蜂天敌(膜翅目:小蜂总科, 姬小蜂科)

1986年,原吉林省林业生防中心站(现为吉林省林业科学研究所)同中国科学院动物研究所合作,对吉林省杨树蛀千害虫的寄生蜂资源进行了开发利用研究。本文是该项研究成果的第一篇报道,记述了三种姬小蜂天敌,包括寄生白杨透翅蛾的透翅蛾黑姬小蜂Elachertus nigritulus(Zett.)和寄生杨窄吉丁的一新种丽凹面姬小蜂 Eniedon epicharisHuang及一新记录种 Eniedon zanara Walker。其它研究成果将陆续报道。     

浅谈白杨透翅蛾防治的几种方法

本文介绍了白杨透翅蛾的概念、特点及它的生长过程,适合它的生长环境,总结了它的生长过程及环境,介绍了它的几种防治措施。     

醋栗透翅蛾的发生及其防治

<正> 醋栗透翅蛾Synanthedon tipuliformis(Clerck)属鳞翅目透翅蛾科,是目前黑龙江省黑穗醋栗的重要新害虫。其幼虫为害新梢和多年生枝条。一般老栽培区重于新栽培区,枝条受害率达20～50％。1986年作者对其发生及防治进行了较为系统的研究,现将结果整理于下。     

截干及修枝整形对有效枝条萌发能力及其对紫胶虫产紫胶的影响

为了研究紫胶虫的寄主植物久树抚育对紫胶产量的影响,通过对云南元江和红河干热河谷区中的久树分别进行截干和修枝整形处理,调查有效枝条的萌发能力和紫胶产量。结果表明,截干高度及截干处的平均直径对有效枝条的总长度和数量无显著影响,但截干位置的分支数量与有效枝条的总长度和数量显著正相关。保留12支左右枝条的中度模式的修枝整形较轻度和重度模式中有效枝条的长度、直径和表面积更加有利于紫胶生产;截干的高度和截干处平均直径对紫胶产量无显著影响,但截干位置的分支数量、萌发的有效枝条总长、数量和着胶枝长与紫胶产量显著正相关,中度模式的修枝整形亩产和单数紫胶产量最高。截干和修枝整形能够影响紫胶的产量,对寄主植物合理的抚育有助于提高紫胶产量。     

北疆高产棉花密度与打顶时序调控的生态位适宜度研究

以北疆棉区高产 (2 0 0 0kg·hm-2 )棉花 (G .hirsutumL .)为研究对象 ,引进生态位适宜度理论对受密度和打顶时序调控的高产棉花生态位适宜度进行了研究。经果表明 ,在密度梯度上 ,随密度增加棉花生态位适宜度值增加。 1 5 0× 1 0 3 株·hm-2 密度下 ,分次打顶降低了生态位适宜度 ,导致减产 ;在高密度种植条件下 ,分期打顶能提高生态位适宜度 ,有利于提高产量。在 2 2 5× 1 0 3 和 30 0× 1 0 3 株·hm-2 密度条件下 ,与同密度下 1次打顶 (7/5 )相比 ,2次打顶增产 4 5 %和 1 1 3%,3次打顶增产 7 5 %和 5 9%。 1 5 0× 1 0 3 株·hm-2 密度下 ,棉田苗蕾期LAI较小、漏光损失大 ,光合势低 ,是实现超高产的主要限制因子 ,花铃期的分期打顶导致减产。在 2 2 5× 1 0 3 和 30 0× 1 0 3 株·hm-2 密度条件下 ,棉花苗蕾期LAI增加 ,分期打顶保证了花铃期较适宜的LAI ,提高了棉花生态位适宜度 ,有利于提高产量 ;1次打顶处理 (7月 5日 )比本区生产上的打顶时间 (7月 1 0日左右 )提早了 5d左右 ,使高密度棉花群体LAI的发展受到了一定程度地限制 ,避免了因密度高群体透光条件的恶化而降低了其生态位适宜度值 ,造成减产损失。     

三唑磷对葡萄透翅蛾毒力作用方式研究

三唑磷（triazophs）是一种中等毒性的有机磷触杀、胃毒杀虫剂。葡萄透翅蛾幼虫接触或取食10mg/L药液处理的葡萄茎叶就可致死;100mg/L以上药液对葡萄新梢枝有较强内渗作用,能渗入梢内组织毒杀施药前10余天至施药后10余天孵化蛀入的幼虫。1次施药的有效杀虫时间前后长达20多天,相当葡萄透翅蛾全年孵化期。掌握孵化高峰喷施100～200mg／L三唑磷农药,1年只要施药1次就能消除葡萄透翅蛾的危害,是目前年一次性药剂防治的首选药剂。     

杨干透翅蛾生物学及防治

杨干透翅蛾Sesiasiningensis（Hsu）是杨树的重要蛀干害虫之一。在国内主要分布于山西、青海、甘肃、内蒙古。在晋中地区为害猖獗。1980年以来,太谷县、祁县、榆次市等平川6县（市）大面积杨树遭受危害。树干基部被钻蛀,不仅影响树木生长,而且极易风倒。太谷县1986年一场6级大风刮倒26万株被害杨树,可见其对杨树生长已构成严重威胁。1986～1993年作者对该虫在晋中地区的发生为害特点和防治方法进行了研究。1形态特征（见图）成虫：前后翅均透明,前翅狭长,后翅扇形,缘毛深褐色。雌虫体长25～30mm,翅展45～S50mm,触角棍棒状,端部…     

弗氏窄吉丁对山杨和钻天杨危害特性的差异

[目的]弗氏窄吉丁Agrilus fleischeri Obenberger是我国东北地区新发现的一种杨树蛀干害虫。为探讨该害虫的有效防治策略,指导生产上科学营林,我们调查研究了弗氏窄吉丁对本地杨树山杨Populus davidiana及外来引种杨树钻天杨Populus nigra var.italica的危害情况。[方法]试验设置了钻天杨与山杨两块纯林样地,采用完全随机取样法于两样地内各选取20株样木进行环割以诱集弗氏窄吉丁。调查两树种的自然受害和人工胁迫后的受害情况,通过解剖感虫株分析虫口密度、死亡率及天敌种类。[结果]钻天杨的自然受害株率(11.76%)显著高于山杨(0),人工环割后钻天杨和山杨的受害株率分别为90%和65%,感虫的钻天杨和山杨平均虫口密度分别为61.95头/株和34.89头/株。钻天杨树上的卵孵化率(91.78%)显著高于山杨(77.61%)。弗氏窄吉丁幼虫在钻天杨树上的蛀道长度(48.68 cm)与山杨(29.59 cm)相比差异显著。对比两树种上的蛹室,发现其长度、宽度和深度差异不明显。分析比较弗氏窄吉丁成虫羽化孔在两树种上的分布,发现在钻天杨上主要分布在1~6m的主干,山杨为1~3m。此外,两样地中弗氏窄吉丁幼虫的生态位宽度也存在不同,钻天杨林中为0.53,山杨林中仅为0.32。[结论]研究结果显示,相对于本地树种山杨而言,非本地的引种树种钻天杨更易感虫。研究结果可为生产上防治该害虫和受害林分的合理改造提供基础信息和科学依据。     

Notes on the biology and ecology of the parasitoids of the poplar clearwing moth, Paranthrene tabaniformis (Rott.) (Lep., Sesiidae) in Bulgaria. II. Eriborus terebrans (Gravenhorst, 1826) (Hym., Ichneumonidae)

The biology and ecology of Eriborus terebrans (Grav.), a parasitoid of the poplar clearwing moth, Paranthrene tabaniformis (Rott.), were studied during the period 1987–98. One-year-old poplar ( Populus spp.) shoots infested with P. tabaniformis larvae were collected from poplar seedlings at 11 localities in Bulgaria and examined in both field and laboratory conditions. Eriborus terebrans was recorded in seven localities as a solitary internal larval parasitoid of P. tabaniformis which developed two generations in early and mid-stage host larvae. Eriborus terebrans overwintered as a larva in P. tabaniformis overwintering larvae. In the field adult parasitoids of the overwintering generation appeared between late April/early May, and June or July. The peak activity of E. terebrans adults only coincided with the beginning of host emergence, which resulted in low levels of parasitism, being no more than 6.2%. Parasitoid adults of the summer generation appeared in late June–mid August. In this period enough larvae of the host were suitable for attacking and parasitism reached 24.4–39% in some cases. The average mortality of P. tabaniformis overwintering larvae caused by this parasitoid in Bulgaria during the period of the study was 4.7%. A significant part of the parasitized P. tabaniformis larvae constructed tunnel structures of frass and silk threads over the external openings of the galleries. It is possible that these structures protect the parasitoid cocoons from natural enemies – hyperparasitoids and predators.     

Notes on the biology and ecology of the parasitoids of the poplar clearwing moth, Paranthrene tabaniformis (Rott.) (Lep., Sesiidae) in Bulgaria. I. Apanteles evonymellae (Bouché, 1834) (Hym., Braconidae)

Aspects of the biology and ecology of Apanteles evonymellae (Bouché), a parasitoid of the poplar clearwing moth, Paranthrene tabaniformis (Rott.), were studied during the period 1987–96. One-year-old poplar ( Populus spp.) shoots infested with P. tabaniformis larvae were collected during the winter months at 11 localities in Bulgaria and examined in the field and laboratory. Apanteles evonymellae was recorded in all areas studied in Bulgaria. The mortality of P. tabaniformis caused by this parasitoid in various regions of Bulgaria varied from 2.4 to 35.4%; the average for the country was 17.3%. Laboratory observations showed that A. evonymellae is a solitary endoparasitoid of the poplar clearwing moth. It develops in early-stage (first- to fourth-instar) host larvae and overwinters as a larva in the host. Apanteles evonymellae is bivoltine, but only the second generation is associated with P. tabaniformis . In the field, adult parasitoids of first generation appear in April about 1 month before the emergence of P. tabaniformis . The longevity of A. evonymellae adults is a maximum of 6 days. Therefore, in the spring, A. evonymellae cannot attack neonate P. tabaniformis larvae and must develop in alternative hosts. Prior to their death the parasitized P. tabaniformis larvae construct conical structures, 'refuges' of frass and silk threads over the external openings of the larval galleries. Apanteles evonymellae pupates in these refuges after the host's death. This modified behaviour of the parasitized host larvae probably protects the pupae of A. evonymellae from hyperparasites and predators.     

The physiological role of abscisic acid in the rooting of poplar and aspen stump sprouts

The better rooting performance of stump sprouts offers the means of mass-producing rooted cuttings of many difficult-to-root genotypes. To study the physiological basis of rooting, stem cuttings were taken from stump sprouts of the more readily-rooted hybrid poplar cultivar DN ( P. deltoides × P. nigra ) and the difficult-to-root aspen hybrid cultivar AE ( P. alba × P. tremula ). Seasonal variation in rooting percentage of both the AE and DN cultivars (higher in winter and lower in late summer and fall) of poplar was correlated with higher and lower levels of abscisic acid (ABA), respectively, in fractionated extracts of poplar. The presence of ABA in the purified inhibitory fraction was unequivocally confirmed by (i) co-chromatography, (ii) gas chromatography-electron capture detector and isomerization with UV light and (iii) combined negative chemical ionization-mass spectrometry. Although ABA was identified in the inhibitory fractions of mung bean bioassays of both poplar and aspen extracts, exogenous ABA did not inhibit rooting when applied at physiological concentrations. Since ABA levels were higher in the more readily-rooted hybrid poplar cultivar DN and were higher in February, close to the time of maximal rooting of cuttings, this suggests that ABA levels may possibly explain clonal and seasonal variation in rooting patterns of poplar stump sprouts. This interpretation is supported by the fact that lower, physiological concentrations increased rooting percentage, root number and root elongation when ABA was added to poplar and aspen cuttings.     

Species richness and altitudinal variation in the aquatic metazoan community in bamboo phytotelmata from north Sulawesi

We compared the aquatic metazoan community structure in bamboo stumps between a lowland (Kosinggolan; 200 m a.s.l.) and a highland site (Moat; 1030–1050 m a.s.l.) in North Sulawesi. The lowland bamboo stumps harbored 38 taxa including 2 predators, and the highland stumps harbored 35 taxa including 2 predators. In total 45 taxa were recorded, including 3 predators. Dominant detritivores were Tipulidae, Scirtidae, Chironomidae, Culicidae and Ceratopogonidae. The sole dominant predators wereToxorhynchites mosquito larvae, which occurred in 67% and 28% of stumps at the lowland and the highland sites, respectively. Although the mean biomass per stump did not differ significantly between the sites, the mean number of species per stump was significantly smaller at the lowland site. In addition, the variation in species composition among stumps was greater at the lowland site than at the highland site. Among dominant taxonomic groups, the number of non-predatory culicid species per stump was smaller at the lowland site where their predator,Toxorhynchites, was more abundant, although both sites had the same number of culicid species. In the presence ofToxorhynchites, the density and biomass of other culicids per stump were reduced significantly. The difference in predator density might affect differences in the local-scale community structure of individual bamboo stumps.     

Distributions of larval mosquitoes among bamboo-stump pools which vary in persistence and resource input

We studied the seasonal occurrence and the distribution patterns of larval mosquitoes in a bamboo grove in northern Kyushu, Japan. The number of pools was large from June to August and was small in winter. Deep stumps and semi-closed-type stumps held water more persistently than shallow and open-type stumps, respectively. Open-type stumps trapped more leaves than semi-closed-type stumps and the number of leaves trapped in the open-type stump was positively correlated with the area of the pool. The incidences ofTripteroides bambusa andAedes albopictus were low early in their breeding season and gradually increased thereafter. In August, the density ofT. bambusa larvae per pool was higher in the old (>2 months) pools than in the new pools and was positively correlated with the depth of the stumps. In contrast, the density ofA. albopictus did not differ significantly between the new-and old pools and was not significantly correlated with the depth of the stump. The density ofA. albopictus was positively correlated with the number of leaves that had been trapped in the stump, whereas the density ofT. bambusa was not. In addition to the seasonal fluctuation in habitat-patch availability, the variations in habitat persistence and resource input among bamboo stumps may facilitate the coexistence of the two mosquitoes that were differentially limited by these factors.     

Sprout recruitment and self-thinning of Erica multiflora after clipping

Regrowth after clipping and the effect of local competition were studied in a natural population of Erica multiflora in a Mediterranean shrubland, by removing neighbours at 1 and 2 m around the target plants during four growing seasons. Removal of surrounding natural vegetation increased the number, the density (number of sprouts per stump area) and the biomass of the sprouts growing from clipped plants. Target plants ònly interacted with their near neighbours. Target plants had a negative relative increment in the number of sprouts per stump during the 18 months immediately following treatment, but a positive increment thereafter, which suggests that there was a constant or episodic recruitment of sprouts within the stump after clipping. Competition treatment had a non-significant effect on the negative increment of sprouts per stump. The self-thinning trajectory was different for the different competition treatments: there was an allometric negative relationship between density of sprouts and mean biomass of survivors during all sampling periods in genets without neighbours in a 1-m radius; the self-thinning trajectory of sprouts in genets without neighbours in a 2-m radius was short, a net increase in sprouts per stump area was accompanied by an increase in mean sprout biomass 30 months after clipping. During the same period, however, plants with neighbours showed a decline in both the sprout biomass and density.     

Screening hybrid poplar clones for susceptibility to Cryptorhynchus lapathi (Coleoptera: Curculionidae)

The poplar-and-willow borer, Cryptorhynchus lapathi (L.) (Coleoptera: Curculionidae), is a wood-boring pest of economic importance in irrigated hybrid poplar (Populus spp.) farms in eastern Washington and Oregon. There is no practical insecticide control tactic against either the larval or adult stage of C. lapathi. To assess variability in C. lapathi toward clone preference, we initiated a no-choice study on 180 caged trees that consisted of five clones in a randomized complete block design. C. lapathi was significantly more successful at establishing a population in two clones with Populus trichocarpa X P. deltoides (TxD) parentage (female x male) than in either of two clones with P. deltoides x P. nigra (DxN) parentage (female x male), or a single clone with P. deltoides x P. maximowiczii (DxM) parentage (female X male). There were no significant differences in the rate of weevil development among infested clones, with the exception of DxM trees. Larvae in DxM clones developed on average to the fourth size grouping and those in the two TxD clones developed on average to the fifth size grouping, and this difference was significant. These results corroborate our general damage surveys conducted in the field. Our findings provide growers with the option to choose less susceptible varieties when replanting.     

Patterns and monitoring of Sesia apiformis infestations in poplar plantations at different spatial scales

Poplar plantations are expanding worldwide but little is known about the hornet clearwing moth, Sesia apiformis, one of their most severe pests. Thirty‐two poplar plantations of I‐214 clone were sampled in Spain, according to a factorial design combining stand age, site condition and understorey management to investigate the main drivers of S. apiformis habitat selection at both tree and stand level. In each plantation, one pheromone trap was activated during the flight season to test the correlation between captures and percentage of attacked trees. The proportion of other poplar forests in surrounding landscapes was calculated and used as a covariate in predictive models of trap catches. There were significantly more attacked trees in older stands. In young stands, the percentage of infested trees increased with the percentage cover of understorey vegetation. There was no significant effect of site quality on the rate of infestation and no difference in tree height, diameter or crown condition between attacked and un‐attacked trees within each stand, suggesting that S. apiformis could behave as primary pest. We hypothesized that the critical stage in the life cycle of the moth was the first instar larvae, which may benefit from protection of deep bark cracks in older stands and understorey vegetation in younger stands. We observed a positive correlation between trap capture and percentage of attacked trees in a radius of 100 m around the trap. The regression of trap catches against percentage of attacked trees was improved when the area of other poplar plantations within a distance of 600 m was incorporated in the model. This suggests that surrounding poplar stands may act as sources of immigrating moths in monitored stands. Our findings confirm that S. apiformis should be considered as a potential threat to poplar plantations and that pheromone trapping provides a suitable monitoring tool.     

温度对转基因741杨抗虫性的影响

在不同温度下测定转基因741杨的抗虫性,发现转抗虫基因741杨的抗虫性与温度密切相关．随着温度的升高,舞毒蛾幼龄幼虫的总死亡率、累计死亡率均明显升高,且随着昆虫龄级的增加,幼虫对转基因株系和温度的敏感性逐渐降低．温度对取食对照株系的昆虫生长发育有促进作用．温度高,舞毒蛾幼虫的生长发育明显加快,历期缩短,各龄期体重、排粪量增长快,而以转基因杨饲喂的昆虫发育进度随温度变化差异不显著．对1998～2000年温度资料和相应的杨扇舟蛾死亡率建立了回归方程,各高抗和中抗株系的温度-昆虫死亡率曲线均表现为明显的回归关系．     

Oviposition patterns of the pine weevil Hylobius abietis

Spatial and temporal distributions of eggs laid by the pine weevil Hylobius abietis (L.) (Coleoptera: Curculionidae) were studied by taking root and soil samples around pine stumps on a clear-cutting in central Sweden. In addition, first-instar larvae migrating in the soil were sampled using traps baited with host-odour. Eggs were found in the soil rather than in the bark of stump roots, which previously has been regarded as the usual oviposition site. Based on an oviposition experiment and additional field observations we conclude that eggs are laid in the bark of roots only when the surrounding material is likely to dry out. We suggest two explanations for why weevils oviposit mainly in the soil, although they are known to show stereotypic behaviour when inserting eggs in stump roots: (1) egg predation by other arthropods or by conspecifics is avoided, and (2) newly hatched pine weevil larvae are better than ovipositing females at locating suitable sites for larval feeding.