MYC 8005, an antibiotic against spider mites. 2. Growth inhibition and pseudo-sterilization in insects and mites

The antibiotic MYC 8005, known as an acaricide, appeared to possess strong growth inhibiting properties, not only in immature stages of spider mites but also in larvae of several insect species. Adult mites and insects seemed not to be affected. However, the fecundity of femaleTetranychus cinnabarinus was strongly reduced by deposits of MYC 8005 on the leaves of bean plants. The feeding of adult houseflies and Colorado potato beetles with MYC 8005 resulted in complete or almost complete sterilization of the insects. The sterilizing effect appeared to be caused by inhibition of maturing processes, in particular of yolk formation in the eggs, whereas follicles looked normal. These facts, and the strong reduction of the fat body in treated insects, suggest that the lipid and protein metabolism are disturbed by MYC 8005.     

Pharmacokinetics of pyrethroids in twospotted spider mites

The penetration and degradation of six pyrethroids were examined in the twospotted spider mite, Tetranychus urticae Koch, and the results were related to their toxicity as measured by inhibition of respiration using the Warburg technique and mortality using the slide-dip bioassay. FMC-54800 [1,1′-biphenyl-3ylmethyl cis-3-(2-chloro-3,3,3-trifluoro-1-propenyl)-2,2-dimethylcyclopropanecarboxylate] was the most toxic pyrethroid to the mites based on both respiration and mortality studies. It and flucythrinate had the highest pharmacokinetic efficiency as determined by delivery and maintenance of internal levels of parent compounds. Permethrin, fenvalerate, and fluvalinate were intermediate in pharmacokinetic efficiency, whereas cypermethrin was significantly lower. The highest intrinsic activity, as estimated by the percentage inhibition of respiration per microgram of internal parent, was possessed by cypermethrin and FMC-54800. Fenvalerate and fluvalinate had intermediate levels, while permethrin and flucythrinate had significantly lower capacities to inhibit respiration. The combination of relatively high pharmacokinetic efficiency and intrinsic activity of FMC-54800 appeared to be responsible for its high toxicity. In addition to these findings, differences in the kinetics for cis and trans isomers were observed for permethrin but not cypermethrin. This study has yielded evidence that acaricidal activity of pyrethroids can be enhanced by optimizing the structure for increased pharmacokinetic efficiency and increased intrinsic activity.     

影响捕食螨防治柑橘害螨效果的主要因素与对策

由于过渡依赖化学农药防治柑橘病虫害,诱发柑橘害螨猖獗,为害程度加剧。为提高害螨综合防控效果,推广以螨治螨技术,本文对影响捕食螨防治柑橘害螨田间效果的果园生态系统、释放时机、田间管理与化学防控等主要因子进行了分析,同时提出了应对策略。     

Bud necrosis,a storage disease of tulips. III. The influence of ethylene and mites

Experiments demonstrated that bud necrosis in tulip bulbs is caused by mites that penetrate the flower bud during storage. This penetration is only possible if the buds, which are normally closed, are open at their tips. Such buds were found after administration of ethylene (3 ppm) during storage at 20°C shortly after lifting and in Red Champion also after storage at higher temperatures (20 to 23°C) in ethylene-free atmospheres. Open buds, caused by ethylene, resulted from unequal growth inhibition of the young leaves and stamens. The difference in sensitivity of both organs to ethylene decreased during storage. later on, the growth inhibition of stamens and leaves became equal, and the buds remained closed. Then ethylene caused blasting of the flower buds. Open buds in Red Champion, caused by higher storage temperatures, resulted from aberrant differentiation of the tips of the young leaves.The production of ethylene by tulip bulbs infected withFusarium oxysporum f.tulipae was measured and proved to be sufficiently high to cause open buds in non-infected bulbs stored in the same room if ventilation is not adequate. The highest production of ethylene, averaging 140 l/24 h/bulb was found at a storage temperature of 20°C.Samenvatting Proeven toonden aan dat kernrot in tulpebollen wordt veroorzaakt door mijten (Rhizoglyphus echinopus Fumouze & Robin enTyrophagus spp.) als deze tijdens de bewaring in de bloemknoppen binnendringen (Tabel 2 en 3). Dit konden mijten alleen bij knoppen die aan de top open waren; normaal zijn de knoppen gesloten. Open knoppen ontstonden door blootstelling van de bollen aan ethyleen (3 dpm) bij 20°C vlak na het rooien (Tabel 1 en Fig. 2) en bij bollen van Red Champion ook door bewaring bij hoge temperaturen (20 tot 23°C) in een ethyleen-vrije atmosfeer. Dit laatste berustte op een afwijkende differentiatie in de top van de pas aangelegde bladeren (Fig. 3). Ethyleen kon open knoppen doen ontstaan, doordat de lengtegroei van de jonge bladeren sterker werd geremd dan die van de meeldraden (Fig. 1). De snellere groei van de binnenste delen van de knop resulteerde dan in open knoppen. Het verschil in gevoeligheid van beide organen voor ethyleen was het grootst vaak na het rooien en nam af gedurende de bewaring. Later in het seizoen (na augustus) was de remming van meeldraden en jonge bladeren gelijk (100%) en ontstonden geen open knoppen meer. Ethyleen veroorzaakte toen verdroging van de bloemknoppen.De door ethyleen geïnduceerde groeiremming was ten dele reversibel. De groei van de jonge bladeren herstelde gedeeltelijk; de groei van de meeldraden geheel, tenzij verdroging van deze organen had plaats gehad als gevolg van blootstelling aan ethyleen laat in het seizoen. Door het verschil in reversibiliteit van de groeiremming van meeldraden en loofbladen kan de toename van de mate van knopafwijking tijdens verdere bewaring na de toediening van ethyleen verklaard worden (Tabel 1).De ethyleenafgifte van bollen die metFusarium oxysporum f.tulipae waren geïnfecteerd, is gemeten. De geproduceerde hoeveelheden ethyleen bleken afhankelijk te zijn van de bewaartemperatuur. Gemiddeld werd de grootste hoeveelheid gevonden bij 20°C, namelijk: 140 l per dag per bol (Fig. 4). Deze hoeveelheid blijkt voldoende te zijn om in slecht geventileerde ruimten bij bollen die niet doorFusarium zijn aangetast, bovengenoemde abnormale groei te veroorzaken.     

广州市植绥螨调查名录

2006年,经2次本底资源调查共得到广州市植绥螨科5属28种,其中尼氏真绥螨是优势种,占采集标本总数的45%。本文还对一些在生物防治上有利用价值的种类作了重点介绍。     

螨类核酸分子系统学研究概况

本文从研究对象、方法、内容等方面概述了近年来螨类,尤其是粉螨科、叶螨科等种类核酸分子系统学研究进展情况。     

Mango Eriophyid mites in relation to inflorescence

Following the appearance of inflorescence malformations on mango trees in some orchards in Israel, a survey was carried out of the presence of Eriophyid mites on mango, and their possible effect on inflorescence malformation was studied. Two Eriophyid species were recorded for the first time from this area. One of them,Erio-phyes mangiferae, associated with mango trees, has no direct effect on inflorescence malformation, but its interaction with another biotic factor is not excluded.     

同工酶技术在螨类研究工作中的应用概况

对同工酶技术在螨类研究工作中的应用概况作一简要综述。     

12种橘园常用农药对3种捕食螨的毒力

采用玻片浸渍法测定了12种药剂对3种捕食螨的毒力.结果表明,在5种杀螨剂中,炔螨特的毒力最低,阿维·哒螨灵的毒力最高;在5种杀虫剂中,噻嗪酮的毒力最低,高效氯氰菊酯的毒力最高;在2种杀菌剂中,代森锰锌的毒力低于咪鲜胺.但同种药剂对不同捕食螨的毒力不同,3种捕食螨对炔螨特的敏感性依次为胡瓜钝绥螨[Amblyseius(Neoseiulus) cucumeris]＜巴氏钝绥螨[Amblyseius(N.) barkeri]＜尼氏真绥螨(Euseius nicholsi),而对阿维·哒螨灵则为尼氏真绥螨＜胡瓜钝绥螨＜巴氏钝绥螨.     

Metabolism of diflubenzuron by spider mites and bean plantsa

Diflubenzuron was absorbed and metabolised relatively slowly by the two-spotted spider mite Tetrunychus urticae Koch. Diflubenzuron metabolites, tentatively identified by coincident chromatography with reference standards, included 4- chlorophenylurea, 2, 6-difluorobenzoic acid, 4-chloroformanilide, 2, 6-difluoro-benzamide, and two compounds monohydroxylated in the chloroaniline moiety. There was little absorption of diflubenzuron when applied topically to leaves of bean plants. However, there was translocation of radioactive material when diflubenzuron was injected into the stern. In this case, the radioactivity, which was confined largely to vascular tissue, apparently moved acropetally but exhibited very little or no basipetal movement. Bean plants metabolised injected diflubenzuron, and certain of the metabolites were similar to those isolated from mites.     

利用植绥螨为主的粉虱生物防治研究进展

粉虱是严重为害农林生产的类群。当前已研究利用较多的粉虱天敌主要是寄生蜂、瓢虫、捕食蝽、病原微生物等。植绥螨是农林害虫、害螨的重要天敌。同时,植绥螨作为粉虱天敌的利用已渐被认可,因其易人工大量饲养、生产成本低、有较强的种群控制能力等,使其对粉虱的防治具有较好应用前景。     

进口原糖中甜果螨和粗角粉螨的分离与鉴定

近几年来,我国检疫工作者多次从进口的原糖中发现螨类,本文对在原糖中发现的甜果螨和粗脚粉螨从形态特征、检验方法方面进行了介绍.     

Effects of acaricides on Oligonychus sp. and compatibility with predatory mites Neoseiulus californicus and Phytoseiulus persimilis

Journal of Plant Diseases and Protection - In Mexico, outbreaks of phytophagous papaya mites (Oligonychus sp.) can threaten papaya production by damaging young leaves, causing a reduction in plant...     

浙江柑橘全爪螨对炔螨特的敏感性变化

2004年比较了浙江省4个橘园柑橘全爪螨对炔螨特的敏感性差异,仅发现LC50相差1.1～1.4倍。同一地区的全爪螨田间种群在1998-2004年间对该杀螨剂的敏感性也基本保持不变。结果表明:浙江橘区的柑橘全爪螨对炔螨特仍未产生明显的抗性,仅部分用药较多、用药历史较长地区的敏感性有所下降。连续4年停用炔螨特后的橘园,其柑橘全爪螨对炔螨特的敏感性得到明显恢复。     

Testing banker plants for biological control of mites on roses

We tested whether plant species used in a banker plant system influence the success of a biological control program with predatory mites. Banker plants (BP) may sustain a reproducing population of predators and provide long-term pest suppression. In an experiment lasting 12 weeks, we analyzed the responses of the predatory mite Amblyseius californicus and the pest mite Tetranychus urticae to eight species of potential BP with different morphological structures. Every BP was paired with a rose plant and infested with pest and predatory mites. The measured parameters were vitality and growth of the plants and numbers of predators, pests and their eggs. Reproduction and establishment of the pest and predatory mites differed among plant species as well as plant growth and vitality. Vitis riparia and Viburnum tinus were the most efficient BP in this combination of pest–predator species. Their presence resulted in best health of the rose crops, highest number of predatory mites and lowest number of pests. Both these BP possess domatia which may be responsible for the efficiency in hosting predatory mites. Overall, the species which fulfilled the requirements of a BP best was the local shrub V, tinus, which bore no pests and a very large number of predators and has a compact growth form suited for application in greenhouses. Although our study gives only evidence for an artificial system with a high BP:crop ratio, high numbers of introduced predators and short distances between plants, this study contributes to knowledge of BP systems and to improve the understanding of the criteria for the choice of local plant species to be used as BP for biological control in IPM.     

Efficacy of selected pesticides against synanthropic mites under laboratory assay

BACKGROUND: The efficacies of organophosphate pesticides, single‐compound versus multicompound pyrethroid formulations and relatively novel unclassified insecticides/acaricides were compared to find the lowest dosage and highest efficacy for the control of Dermatophagoides farina (Hughes), D. pteronyssinus (Trouessart) and Tyrophagus putrescentiae (Schrank). Formulated active ingredients (AIs) were diluted in water and applied onto filter paper in experimental chambers with ten unsexed adult mites in six replicates. Mite mortality was checked after 24 h. The security index (SI) was calculated for all of the AIs by dividing the recommended rate by the LD₉₀ determined for each species. RESULTS: The tested organophosphates had high LD₉₀ and low SI values. The single‐compound pyrethroids were ineffective (deltamethrin and beta‐cyfluthrin) or had high LD₉₀ and low SI values (cyphenothrin, permethrin, pyrethrum and bifenthrin). The multicompound miticides had low LD₉₀ and high SI values which increased from deltamethrin/S‐bioallethrin to permethrin/S‐bioallethrin/piperonyl butoxide to permethrin/pyriproxyfen/benzyl benzoate. Abamectin, pyridaben, propargite and flufenoxuron were highly active against Dermatophagoides spp. Neem (Acarosan duo) was highly active against all mite species tested. CONCLUSION: The available formulations of multicompound pyrethroids (permethrin/S‐bioallethrin/piperonyl butoxide, permethrin/pyriproxyfen/benzyl benzoate), benzyl benzoate, neem and some field acaricides are effective in suppression of synanthropic mites in laboratory assays. Their LD₉₀ are lower than those of traditionally used organophosphates or single‐compound pyrethroid formulations. Copyright © 2011 Society of Chemical Industry