中国云南西双版纳蟹蛛一新属及三新种描述(蜘蛛目,蟹蛛科)

描述了采自云南西双版纳热带雨林的蟹蛛1新属:副泥蟹蛛属Paraborboropactus gen.nov.及3新种:郑氏副泥蟹蛛,新种Paraborboropactus zhengi sp.nov.,豆荚副泥蟹蛛,新种 Paraborboropactus leguminaceus sp.nov.以及菱形副泥蟹蛛,新种Paraborboropactus rhombus sp.nov,.模式标本均保存在中国科学院动物研究所.     

The microbiota in spider mite feces potentially reflects intestinal bacterial communities in the host

Microorganisms provide many physiological functions to herbivorous hosts. Spider mites (genus Tetranychus) are important agricultural pests throughout the world; however, the composition of the spider mite microbial community, especially gut microbiome, remains unclear. Here, we investigated the bacterial community in five spider mite species and their associated feces by deep sequencing of the 16S rRNA gene. The composition of the bacterial community was significantly different among the five prevalent spider mite species, and some bacterial symbionts showed host‐species specificity. Moreover, the abundance of the bacterial community in spider mite feces was significantly higher than that in the corresponding spider mite samples. However, Flavobacterium was detected in all samples, and represent a “core microbiome”. Remarkably, the maternally inherited endosymbiont Wolbachia was detected in both spider mite and feces. Overall, these results offer insight into the complex community of symbionts in spider mites, and give a new direction for future studies.     

The invasive spider mite Tetranychus evansi (Acari: Tetranychidae) alters community composition and host-plant use of native relatives

The tomato spider mite Tetranychus evansi Baker and Pritchard (Acari: Tetranychidae), is a worldwide pest of solanaceous crops that has recently invaded many parts of the world. In the present study we examined the ecological impact of its arrival in the Mediterranean region. The spider mite and phytoseiid mite assemblages in various crop and non-crop plants in three areas of Valencia (Spain) were studied a few months before and 10 years after the invasion of T. evansi. According to rarefaction analyses, the invasion of T. evansi did not affect neither the total number of species in the mite community examined (spider mite and phytoseiid species) nor the number of species when the two communities were examined separately. However, after the invasion, the absolute and relative abundance of the native Tetranychus species was significantly reduced. Before the invasion, T. urticae and T. turkestani were the most abundant spider mites, accounting for 62.9 and 22.8 % of the specimens. After the invasion, T. evansi became the most abundant species, representing 60 % of the total spider mites recorded, whereas the abundance of T. urticae was significantly reduced (23 %). This reduction took place principally on non-crop plants, where native species were replaced by the invader. Null model analyses provided evidence for competition structuring the spider mite community on non-crop plants after the invasion of T. evansi. Resistance to acaricides, the absence of efficient native natural enemies, manipulation of the plant defenses and the web type produced by T. evansi are discussed as possible causes for the competitive displacement.     

Pest species diversity enhances control of spider mites and whiteflies by a generalist phytoseiid predator

To test the hypothesis that pest species diversity enhances biological pest control with generalist predators, we studied the dynamics of three major pest species on greenhouse cucumber: Western flower thrips, Frankliniella occidentalis (Pergande), greenhouse whitefly, Trialeurodes vaporariorum (Westwood), and two-spotted spider mites, Tetranychus urticae Koch in combination with the predator species Amblyseius swirskii Athias-Henriot. When spider mites infested plants prior to predator release, predatory mites were not capable of controlling spider mite populations in the absence of other pest species. A laboratory experiment showed that predators were hindered by the webbing of spider mites. In a greenhouse experiment, spider mite leaf damage was lower in the presence of thrips and predators than in the presence of whiteflies and predators, but damage was lowest in the presence of thrips, whiteflies and predators. Whitefly control was also improved in the presence of thrips. The lower levels of spider mite leaf damage probably resulted from (1) a strong numerical response of the predator (up to 50 times higher densities) when a second and third pest species were present in addition to spider mites, and (2) from A. swirskii attacking mobile spider mite stages outside or near the edges of the spider mite webbing. Interactions of spider mites with thrips and whiteflies might also result in suppression of spider mites. However, when predators were released prior to spider mite infestations in the absence of other pest species, but with pollen as food for the predators, we found increased suppression of spider mites with increased numbers of predators released, confirming the role of predators in spider mite control. Thus, our study provides evidence that diversity of pest species can enhance biological control through increased predator densities.     

Beat sampling accuracy in estimating spruce spider mite (Acari: Tetranychidae) populations and injury on juniper

The use of a standardized beat sampling method for estimating spruce spider mite, Oligonychus ununguis (Jacobi) (Acari: Tetranychidae), densities on a widely used evergreen ornamental plant species, Juniperus chinensis variety 'Sargentii' A. Henry (Cupressaceae), was examined. There was a significant positive relationship between total spruce spider mite densities and spider mite densities from beat sampling on juniper. The slope and intercept of the relationship may be used by pest managers to predict total spider mite densities on plants from beat sample counts. Beat sampling dramatically underestimates the total number of spider mites on a foliage sample. The relationships between spruce spider mite feeding injury and spider mite density estimates from beat sampling juniper foliage and total spider mite counts on foliage were also examined. There was a significant positive relationship between spruce spider mite density as estimated from beat sampling and injury to the plants. There was a similar positive relationship between the total number of spruce spider mites and injury to the plants, suggesting that a pest manager could use beat sampling counts to estimate plant injury and related thresholds. These findings have important implications to decision-making for spruce spider mite control, especially as it relates to threshold levels and determining rates of predator releases. Further assessment of the effectiveness of beat and other sampling methods across multiple spider mite- host plant associations needs to be examined to enable pest managers to select sampling plans that are feasible and reliable.     

Evaluation of predatory mite (Acari: Phytoseiidae) releases to suppress spruce spider mites, Oligonychus ununguis (Acari: Tetranychidae), on juniper

A laboratory trial evaluated four phytoseiid species for their potential as biological control agents of spruce spider mite, Oligonychus ununguis (Jacobi) (Acari: Tetranychidae). An augmentative biological control approach, using the predatory mites Neoseiulus fallacis Garman and Galendromus occidentalis Nesbitt (Acari: Phytoseiidae), was evaluated for reducing pest mite densities and injury, and economic costs on Juniperus chinensis 'Sargentii' A. Henry (Cupressaceae) in an outdoor nursery. Sequential releases of predator species, individually and in combination, were tested and compared with two commonly used miticides, a low-toxicity miticide, horticultural oil, and a conventional miticide, hexythiazox. Timing of treatments was based on grower-determined need, and predator release rates were based on guidelines in literature received from producers of beneficial organisms. Predator releases were more expensive and provided less effective suppression of spruce spider mites, resulting in greater spider mite injury to plants, compared with conventional pesticides. However, spider mite damage to plants did not differ in an economically meaningful way between treatments. Unsatisfactory levels of control seem related to under estimations of actual spider mite abundance based on grower perceptions and the beat sampling technique used to estimate predator release rates. These data suggest that when initial populations of spruce spider mite are high, it is unlikely that sequential releases of predator species, individually or in combination, will suppress spider mite populations. In this trial, augmentative biological control control was 2.5-7 times more expensive than chemical controls.     

华东地区园林叶螨的初步研究（蜱螨目：叶螨总科）

笔经过数年的调查研究,查知华东园林植物上叶螨种类90种,分属3科22属。章报道了这些种类及其新的寄主植物和分布,研究发现,酢酱草如叶螨,柑桔全爪螨、构始叶螨、截形如螨,神泽叶螨,柏小爪螨,合肥埃须螨,俄勒冈小扁螨,刘氏短须螨和卵形短须螨等为园林植物上的主要种类,二点叶螨和朱砂叶螨是世界性分布的重要害螨。通常被认为是主要种类,但在华东园林植物上分布尚有限,加强检疫防止它们的传播扩散是十分必要的,章讨论了其它有关问题,所有标本均存放于上海农学院园环系农螨研究室。     

巴基斯坦为害杧果树的短须螨属一新种(蜱螨亚纲,细须螨科)

在对巴基斯坦杧果种植区苏加堡的杧果树螨类区系研究中,发现短须螨属(蜱螨亚纲：细须螨科)1新种：礼短须螨。文中记录并描述了该新种。新种的背饰特点是：前背中侧近分颈沟处具网状纹、外侧具纵向条纹;具6对末体背侧毛。雄螨 未采到。正模♀,1994年1月1日采自巴基斯坦,苏加堡杧果园的落叶中;副模1,1994年11月3日采自马尔坦南3km处的杧果树叶,曼苏采。模式标本保存于农业大学农业昆虫系螨类研究室,费沙拉堡,巴基斯坦。新种的背饰独特,略与短须螨属中具7对末体背侧毛的种相像,但具6对末体背侧毛的种皆无此种背饰。     

Response of predatory mites with different rearing histories to volatiles of uninfested plants

The behavioural response of the predatory mite Phytoseiulus persimilis to volatiles from several host plants of its prey, spider mites in the genus Tetranychus, was investigated in a Y-tube olfactometer. A positive response to volatiles from tomato leaves and Lima bean leaves was recorded, whereas no response was observed to volatiles from cucumber leaves, or leaves of Solanum luteum and Solanum dulcamara.Different results were obtained for predators that differed in rearing history. Predators that were reared on spider mites (Tetranychus urticae) on Lima bean leaves did respond to volatiles from Lima bean leaves, while predators that had been reared on the same spider mite species but with cucumber as host plant did not respond to Lima bean leaf volatiles. This effect is compared with the effect of rearing history on the response of P. persimilis to volatile allelochemicals of prey-infested plant leaves.     

LASOFINIUS GEN. N. (COLLEMBOLA: TOMOCERIDAE) FROM TASMANIA AND A RE-EXAMINATION OF NEOPHORELLA DUBIA WOMERSLEY (TOMOCERIDAE)

Lasofinius gen. n. is erected for L. willi sp.n. (type species) and L. gemini sp.n., both from Tasmania. The species are described and a key to separate them is given. Lasofinius is characterised by the retention of a postantennal organ in adults which is unusual in the Tomoceridae. The closely related monobasic genus Neophorella Womersley from South Africa (type species N. dubia ) is redescribed. The phylogenetic relationships of both genera are discussed and comments made on the distribution and zoogeography of Tomoceridae in Australia.     

壳二孢属几个新种和新记录种

本文报告了壳二孢属(Ascochyta)新种4个:(木忽)木壳二孢(Ascochyta araliae Sun et Bai),朝鲜槐壳二孢(A.maackiae Sun et Bai),假酸浆壳二孢(A.nicandrae Sun et Bai)和花椒壳二孢(A.zanthoxyli Sun et Bai)。建立了新组合1个,即淡竹壳二孢(A.osmophila(Davis)L(?) et Bai))。此外,报告了国内新记录种19个。新种有拉丁文和中文描述及图。标本保存于沈阳农业大学真菌标本室(MHSAU)。     

Spider Mites of Japan: Their Biology and Control

Spider mite biology and control in Japan were reviewed. Seventy-eight spider mite species of 16 genera (Family Tetranychidae) have been recorded in Japan. Several of the species recently described were separated from a species complex comprising strains with different ecological performance such as host range. These separations were first supported by crossing experiments and then confirmed by molecular genetic studies. Spider mite control in Japan is still dependent on heavy acaricide spraying in order to attain products of extremely high quality. The commercial use of natural enemies in spider mite management has just started.