The influence of pollen on combining predators to control Frankliniella occidentalis in ornamental chrysanthemum crops

Small scale glasshouse trials showed that second instar nymphs of Orius laevigatus reduced Frankliniella occidentalis numbers (78-92%) more than Neoseiulus cucumeris (0-30%). Combining the predators did not increase reduction of thrips numbers (84-93%). Pollen did not increase thrips control, but led to an increase in the number of thrips.     

Influence of species of host plants on the predation of thrips by Neoseiulus cucumeris, Iphiseius degenerans and Orius laevigatus

A leaf-disc bioassay was used to compare the predation levels of two species of predatory mites (Neoseiulus cucumeris (Oudemans) and Iphiseius degenerans (Berlese)) and a predatory bug (Orius laevigatus (Fieber)), on the thrips Frankliniella occidentalis (Pergande) and Heliothrips haemorrhoidalis (Bouché), feeding on a range of susceptible plant species from twelve plant families. The predatory bug, O. laevigatus, reduced the number of thrips to a greater extent than the predatory mites and all three predators showed greater levels of predation on F. occidentalis than on H. haemorrhoidalis. The level of predation caused by each predator varied among the species of plants; the variation was greater on the plant hosts of H. haemorrhoidalis than of F. occidentalis.     

Suppression of aphids on strawberry by augmentative releases of larvae of the lacewing Chrysoperla carnea (Stephens)

In laboratory feeding experiments, larvae of Chrysoperla carnea consumed up to 790 Chaetosiphon fragaefolii during their development. In gauzehouse experiments, releases of C. carnea larvae significantly reduced numbers of C. fragaefolii on potted strawberry plants. In open field experiments numbers of C. fragaefolii were significantly reduced at release rates of eight chrysopid larvae per plant, but a release experiment on larger strawberry plants grown under protection did not give a significant reduction in aphid numbers, even at a release rate of 25 larvae per plant.     

Effectiveness of Orius laevigatus (Hem.: Anthocoridae) for the control of Frankliniella occidentalis on cucumber and pepper in the UK

Biological control of Western Flower Thrips was sought by the use of Orius laevigatus, an anthocorid bug indigenous to the UK. Rearing methods were successfully devised for this species and glasshouse trials on cucumbers and peppers were conducted. It was not possible to obtain full establishment of O. laevigatus on a cucumber crop, but breeding populations established satisfactorily in the flowers of sweet peppers. On peppers, releases totalling one to two Orius per plant resulted in good thrips control over several months providing that initial thrips numbers were low. Early season supplementary lighting using tungsten bulbs to extend the photoperiod ensured good control of thrips on peppers in February and March by promoting Orius breeding on the crop.     

多次释放胡瓜新小绥螨对橘园节肢动物群落多样性的影响

为了探明长期多次释放胡瓜新小绥螨(Neoseiulus(Amblyseius)cucumeris)是否会对橘园节肢动物群落的生物多样性产生影响,我们在福州马尾和晋安试验区的2个橘园分别设置生防园、自然园和化防园,连续两年每月两次在各处理橘园的树冠和地面杂草中采集并记录节肢动物的种类和数量,结果表明两个试验区的物种丰富度(S)均以生防园最高,且都显著高于相应的化防园和自然园;马尾试验区三种处理的多样性指数(H’)和均匀度指数(E)的大小依次为生防园>自然园>化防园,晋安试验区则为自然园>生防园>化防园,表明释放胡瓜新小绥螨防治柑橘害螨,减少农药的使用,能恢复或增加橘园节肢动物群落的生物多样性。此外,释放胡瓜新小绥螨未对橘园原有的捕食螨类群产生影响。     

西花蓟马、二斑叶螨与黄瓜新小绥螨的相互关系研究

西花蓟马Frankliniella occidentalis（Pergande）和二斑叶螨Tetranychus urticae Koch是温室花卉与蔬菜上的重要害虫（螨）。植物常被两者同时危害。黄瓜新小绥螨Amblyseius cucumeris（Oudemans）是世界上广泛应用的温室蓟马的生物防治物,有时也被用来防治二斑叶螨。本研究中,在人工气候室盆栽条件下利用黄瓜新小绥螨防治西花蓟马和/或二斑叶螨。结果显示,当每豆株上接入10或20头二斑叶螨时,按照1∶4的益害比释放黄瓜新小绥螨可有效控制二斑叶螨。同样密度比的情况下,5和10头黄瓜新小绥螨的释放量可显著控制西花蓟马的接入量。二斑叶螨密度的增加没有显著影响到黄瓜新小绥螨对西花蓟马的控制作用。西花蓟马可捕食黄瓜新小绥螨的卵,日捕食量达1.2粒。本文对利用黄瓜新小绥螨防治温室中西花蓟马进行了讨论。     

草莓毛管蚜性外激素腺体的形态及组织观察

本文通过对草莓毛管蚜Chaetosiphon fragaefolii(Cockerell)性外激素腺体外部形态的扫描电镜观察,对腺体的外形、大小、位置、数目作了描述;通过对腺体组织不同发育时期的电镜观察,揭示了该虫性外激素腺体的形成期、释放性外激素期和衰老期等不同发育阶段的变化过程.     

Life tables and predation activity of Orius laevigatus and O. albidipennis at three constant temperatures

Effects of three constant temperatures (15, 25, and 35 -C) on development and reproduction of Orius laevigatus (Fieber) and O. albidipennis (Reuter) (Heteroptera: Anthocoridae) and on their predation activity against the western flower thrips Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) were investigated in the laboratory. Small rooted plants of Spanish pepper (Capsicum annuum L. cv. Creta, long red) served as oviposition substrate and moisture source. Survival of eggs and nymphs of both species was high at 25 and 35 °C. At 15 °C, none of the eggs of O. albidipennis hatched and the number of nymphs completing the immature stage was extremely low. Developmental time of nymphs was not significantly different between species at 15 °C, but at 25 and 35 °C nymphs of O. laevigatus took significantly longer to develop than those of O. albidipennis. Females of O. albidipennis lived longer than those of O. laevigatus at 15 and 35 °C, but no differences were observed at 25 °C. Fecundity of O. albidipennis was greatly reduced at 15 °C, whereas a temperature of 35 °C was close to the upper reproduction threshold of O. laevigatus. Fecundity was highest at 25 °C for both species. At 15 °C, the intrinsic rate of increase (r_m) reached a minimum for both species. For O. albidipennis, the r_m-value increased with temperature (0.121 at 25 °C and 0.202 at 35 °C), whereas for O. laevigatus it peaked at 25 °C (0.105) but decreased at 35 °C (0.051). At 15 and 25 °C, adults of O. laevigatus consumed more F. occidentalis adults during their total lifespan than those of O. albidipennis, but the latter showed a better predation activity at 35 °C; in all treatments, however, adults of O. laevigatus consumed more prey per day than did those of O. albidipennis. The performance of both anthocorids at the different temperatures is discussed in relation to their practical use in integrated pest control programmes.     

Taxonomy and biological control: Neoseiulus cucumeris (Acari: Phytoseiidae), a case study

The predatory mite Neoseiulus cucumeris (Oudemans) (Acari: Phytoseiidae) is an important biological control agent of thrips and other small pests worldwide. Yet, despite its economic importance, this species is poorly defined taxonomically and cannot be reliably separated from other species on the basis of morphology alone. Neoseiulus cucumeris has been reported from Australia, although considerable confusion exists as to whether the Australian material is actually N. cucumeris or a presumed endemic species, Neoseiulus bellinus (Womersley). A morphological investigation of N. bellinus and several geographical 'strains' of N. cucumeris demonstrated that: (i) N. bellinus is a distinct species, the males of which can be morphologically separated from those of N. cucumeris , using setal and cheliceral lengths and number of teeth on the fixed digit; and (ii) N. cucumeris , or a morphologically identical species, is present in Australia. Despite behavioural differences, there are no significant morphological differences between the 'strains' of N. cucumeris . Biosystematic research is a more reliable method of species separation, and such a method is suggested for future work with phytoseiid mites.     

东亚小花蝽(Orius sauteri)成虫对入侵害虫西花蓟马(Frankliniella occidentalis)成虫的捕食作用

为探明东亚小花蝽对西花蓟马的控制效能,开展了东亚小花蝽成虫对西花蓟马成虫的捕食功能反应与寻找效应研究。试验结果表明,在供试温度下,其捕食功能反应符合HollingⅡ型方程。在相同温度下,东亚小花蝽成虫的捕食量随着猎物密度的增加而增大,搜寻效应随着猎物密度的增加而降低。在18～26℃,随着温度的升高,东亚小花蝽成虫对西花蓟马成虫的捕食量增加,而在26～34℃则有相反的趋势。在相同猎物密度条件下,随着东亚小花蝽成虫密度的增大,其平均捕食量逐渐减少,捕食作用率E也相应地降低,捕食作用率E与东亚小花蝽成虫密度P的关系为E=0．5224P^-0.7148,分摊竞争强度,与东亚小花蝽成虫密度P的关系为I=0．9689logP＋0．0763。     

Effect of Amblyseius cucumeris and Amblyseius barkeri as biological control agents of thrips tabaci on glasshouse cucumbers

Biological control of Thrips tabaci by the phytoseiid mites Amblyseius cucumeris and Amblyseius barkeri was investigated on glasshouse parthenocarpic cucumbers. The mite species were used in combination and singly. Successful thrips control was obtained with A. cucumeris alone, whereas control was not reliable with A. barkeri alone nor with the combination of A. cucumeris and A. barkeri. The establishment period was long for both phytoseiid species. At the beginning of the trial, when thrips were absent or very low in numbers, only A. cucumeris was found on the leaves. Mite populations did not increase until the number of thrips were ca. two and five per leaf for A. cucumeris and A. barkeri, respectively. A. cucumeris seemed to show a better numerical response to T. tabaci than A. barkeri. At the end of the trial (three months after the last introduction of mites) only A. barkeri was found in the combination plot, indicating that A. cucumeris is displaced by A. barkeri in situations of interspecific competition between the two species on glasshouse parthenocarpic cucumbers.     

不同温度下双尾新小绥螨对西花蓟马的捕食功能反应

为明确双尾新小绥螨Neoseiulus bicaudus各螨态对西花蓟马Frankliniella occidentalis不同龄期若虫的捕食量及不同温度对其捕食量的影响。本研究通过测定不同温度下24 h内双尾新小绥螨各螨态对不同密度西花蓟马若虫的捕食情况(西花蓟马猎物密度分别为5、10、15、20和25头/室,温度分别设置为23、26、29、32和35℃)。研究结果表明,双尾新小绥螨各螨态对猎物的捕食量随猎物密度的升高而增加。当温度为29℃,雌成螨对西花蓟马1龄若虫捕食量最高,在猎物数为25头/室时,可达4.4头/日。23~32℃内,双尾新小绥螨的雌成螨的捕食量随温度的上升而增加,到达35℃时开始降低。29~32℃双尾新小绥螨的雌成螨对西花蓟马1龄若虫的捕食量最高,可达6.7头/日,最适于其捕食。结果表明双尾新小绥螨对西花蓟马若虫的捕食功能反应类型符合Holling II模型,其对西花蓟马有较好的捕食能力,可利用于西花蓟马的生物防治。     

南方小花蝽对西花蓟马和蚕豆蚜的捕食作用

南方小花蝽Orius similis是多种小型害虫的重要天敌昆虫,为了掌握其控制潜能,本文研究了南方小花蝽对西花蓟马Frankliniella occidentalis和蚕豆蚜Aphis craccivora的捕食作用。研究结果表明南方小花蝽3～5龄若虫和雌成虫对西花蓟马和蚕豆蚜的功能反应均符合HollingⅡ型方程,南方小花蝽3～5龄若虫和雌成虫对西花蓟马2龄若虫的瞬时攻击率均高于蚕豆蚜。南方小花蝽5龄若虫对蚕豆蚜的控制能力比雌成虫强,而对西花蓟马的控制能力比雌成虫差。南方小花蝽5龄若虫对西花蓟马2龄若虫和蚕豆蚜的捕食率（E）随着捕食者自身的密度（P）的增加而下降,其干扰反应方程分别为E=0.412P-1.623和E=0.416P-1.639。南方小花蝽5龄若虫对西花蓟马2龄若虫和蚕豆蚜有明显的选择性,5龄若虫喜欢取食西花蓟马2龄若虫,但前期取食的猎物对其选择性有明显的影响,更喜欢选择前期取食过的猎物。     

外源茉莉酸诱导菜豆对西花蓟马和南方小花蝽的行为反应

【目的】为明确茉莉酸诱导的菜豆对西花蓟马Frankliniella occidentalis和南方小花蝽Orius similis的行为反应。【方法】采用四臂嗅觉仪测定了西花蓟马和南方小花蝽对不同浓度茉莉酸诱导菜豆后的行为反应,并用气相色谱-质谱联用仪测定了不同浓度茉莉酸处理后菜豆挥发物的成分。【结果】不同浓度茉莉酸处理的菜豆植株对西花蓟马和南方小花蝽分别有不同程度的驱避和吸引作用,以1 mmol/L的茉莉酸处理植株对西花蓟马的驱避作用最强,0.1 mmol/L的茉莉酸处理植株对南方小花蝽的吸引作用最强。不同处理菜豆的挥发物在含量和成分上存在显著差异,(Z)-3-己烯丙酸酯、2-异丙基-甲氧基毗嗦只有在茉莉酸处理植株中检测到。结合不同浓度茉莉酸处理植株对西花蓟马和南方小花蝽的行为反应及菜豆挥发物含量的变化趋势,推测(E)-2-己烯醛对西花蓟马有驱避作用,(E)-2-乙酸叶醇酯对南方小花蝽具有引诱作用。【结论】茉莉酸处理菜豆后,植物挥发物种类和含量发生了变化,在增强菜豆植株抗虫性的同时,还可增强捕食性天敌南方小花蝽的搜索和捕食能力。     

东亚小花蝽成虫对西花蓟马若虫的捕食功能反应与搜寻效应

为探明东亚小花蝽对西花蓟马的控制效能,开展了东亚小花蝽成虫对西花蓟马若虫的捕食功能反应与搜寻效应研究。结果表明,在供试温度下,该捕食功能反应符合HollingⅡ型方程。在相同温度下,东亚小花蝽成虫的捕食量随着猎物密度的增加而增大,搜寻效应随着猎物密度的增加而降低。在18℃～26℃内,随着温度的升高,东亚小花蝽成虫对西花蓟马若虫的捕食量增加,而在26℃～34℃则有相反的趋势。在相同猎物密度条件下,随着东亚小花蝽成虫密度的增大,其平均捕食量逐渐减少,捕食作用率也相应地降低,东亚小花蝽成虫之间存在分摊竞争。