Inhibition of egg development by phosphine in the cosmopolitan pest of stored products Liposcelis bostrychophila (Psocoptera: Liposcelididae)

Phosphine-induced delay in development of eggs was investigated as a mechanism of resistance to this fumigant in Liposcelis bostrychophila Badonnel. One-day-old eggs of a susceptible and a strongly resistant strain of L bostrychophila were exposed to a range of phosphine concentrations for 6days at 30 (+/- 1) degrees C and 70 (+/- 2)% RH. Delay in mean hatching period occurred in both susceptible and resistant eggs, although it was more pronounced in the latter. A maximum delay of 2.65 days was recorded for eggs of the susceptible strain at 0.01 mg litre(-1) (the highest concentration at which eggs survived) and 13.39 days for the resistant strain at 1 mg litre(-1) (the highest concentration tested). Delay in egg development time was positively correlated with increasing phosphine concentration. Our results reveal that the most successful strategy to control resistant L bostrychophila is to apply relatively low concentrations of phosphine for extended exposure times (eg 0.05 mg litre(-1) for 16 days) that allow all eggs to hatch to the much less tolerant nymph stage.     

双斑截尾寄蝇对草地螟寄生的主要生物学特征及饲养技术

首次报道了双斑截尾寄蝇(Nemorilla maculosa Meigen)对草地螟(Loxostege sticticalis L.)的寄生行为及发育特征和饲养技术。研究结果表明:双斑截尾寄蝇将卵产在5龄草地螟幼虫的胸部,蝇蛆孵化后直接钻入寄主体腔内发育,幼虫发育成熟后便会钻出寄主体外化蛹。完成卵到幼虫期的发育需约12 d。蛹经11 d左右即可以羽化为成虫。从卵到成虫的发育历期约25 d。雌雄之间卵和幼虫的发育历期没有显著差异,但雌蛹的发育比雄蛹慢。雌蝇羽化后可以立即交配,而雄蝇羽化后约2 d后才能交配。补充营养的雌蝇平均产卵量约为130粒/头。还初步研究了影响双斑截尾寄蝇寄生能力的因素。简单介绍了其室内饲养繁殖技术。     

Development of Khawia sinensis Hsü, 1935 (Cestoda: Caryophyllidea) in the fish host.

The development of the tapeworm Khawia sinensis has been observed up to the stage of sexually mature parasites releasing eggs in an experimentally infected definitive host (Cyprinus carpio) at 15-16 degrees C. Juvenile, maturing, adult and gravid tapeworms were found 2-12, 19-24, 36-62, and 78-91 days post infection, respectively. No apparent size difference between tapeworms from carp kept at 20-22 degrees C, examined 1-16 days post infection, and those from 15-16 degrees C was observed. In naturally infected and fed carp, kept at 21-22 degrees C, some tapeworms survived till the end of experiment (44 days) while in unfed fish they survived only 15 days from the beginning of experiment.     

短时高温暴露对草地贪夜蛾存活及生殖的影响

本文研究短时高温暴露对草地贪夜蛾存活和生殖的影响,为其夏季的预测预报及综合防治提供技术支持.分别以卵、不同龄期幼虫、蛹、成虫作为研究对象进行不同时间高温暴露处理,研究高温暴露处理后幼虫和成虫的成活率,幼虫的化蛹率、羽化率、蛹重以及成虫的生殖能力.结果 表明.37℃对卵的孵化率无显著影响,40℃暴露4h卵的孵化率显著降低...     

Egg-sterilizing effect of benzoylphenylureasvia the adult stage of the nitidulid beetleCarpophilus hemipterus

The effect of a 24-h exposure of adults ofCarpophilus hemipterus to artificial diets treated on the surface with different concentrations of benzoylphenylureas, on the hatchability of eggs laid during the subsequent 14 days, was investigated. The order of persistence of sterilization at 5 ppm was chlorfluazuron (IKI-7899), 12 days > XRD-473, 10 days > diflubenzuron, 6 days > teflubenzuron (CME 134), 4 days. Three of the substances (chlorfluazuron, diflubenzuron and teflubenzuron) had no direct ovicidal effect whenC. hemipterus eggs were dipped in 1000 ppm dilutions, but the larvae that hatched from the treatments died within 2 days.     

Effects of two different neem products on different stages of Nezara viridula (L.) (Heteroptera, Pentatomidae)

In this study, the effects of two different commercial neem insecticides (NeemAzal T/S and Neem Oil) were determined on different stages of Nezara viridula (L.) (Heteroptera: Pentatomidae) under laboratory conditions. Neem Azal and Neem Oil were applied at concentrations of 0.5 % and 2 %, respectively. Mortality was recorded after 3, 7 and 14 days for nymphs and adults; 7 and 14 days for old (4-day-old) eggs; and 14 days for newly laid (one-day-old) eggs. Both products have no significant effect on adults and newly laid eggs. However Neem Oil was found to be more effective than NeemAzal T/S on nymphs and on old laid eggs after 7 and 14 days. It can be concluded that both neem products have potential for insecticidal efficacy (approximately 60 %) against nymphs of N. viridula. at concentrations recommended by manufacturers for registered pests.     

Effects of two different neem products on different stages of Nezara viridula (L.) (Heteroptera, Pentatomidae)

In this study, the effects of two different commercial neem insecticides (NeemAzal T/S and Neem Oil) were determined on different stages of Nezara viridula (L.) (Heteroptera: Pentatomidae) under laboratory conditions. Neem Azal and Neem Oil were applied at concentrations of 0.5 % and 2 %, respectively. Mortality was recorded after 3, 7 and 14 days for nymphs and adults; 7 and 14 days for old (4-day-old) eggs; and 14 days for newly laid (one-day-old) eggs. Both products have no significant effect on adults and newly laid eggs. However Neem Oil was found to be more effective than NeemAzal T/S on nymphs and on old laid eggs after 7 and 14 days. It can be concluded that both neem products have potential for insecticidal efficacy (approximately 60 %) against nymphs of N. viridula. at concentrations recommended by manufacturers for registered pests.     

松毛虫赤眼蜂不同放蜂密度对松毛虫控制效果

使用松毛虫赤眼蜂不同放蜂密度分别于7月30日和8月10日两次放蜂防治松毛虫,第二次放蜂后10d分别调查卵寄生率和虫口密度。结果表明,松毛虫赤眼蜂块剂50、60、70块/667m2三种放蜂密度防治松毛虫均有良好的防治效果,卵寄生率分别为78.8%、75.3%、90.1%,虫口防效达89.1%、84.6%9、1.6%。从经济成本预算,每亩放蜂50块,就可以达到较好的控制效果。     

Toxicity and sublethal effects of an insecticidal soap on Aphidius colemani (Hymenoptera: Braconidae)

BACKGROUND: The effects of an insecticidal soap on the survival, fitness and behaviour of an aphid parasitoid wasp, Aphidius colemani (Viereck), were studied in the laboratory. The LC(50) (soap concentration causing 50% mortality 24 h after treatment) was determined. The survival of parasitoid larvae (% adult emergence), fitness (tibia length of adults) and number of eggs produced per female parasitoid that survived in third- and fourth-instar aphids treated with insecticidal soap LC(50) were also assessed. The LC(50) for third- and fourth-instar aphids was determined to be 3.25 g L(-1). Acceptance by female parasitoids of aphids that survived their LC(50) was also tested. RESULTS: The soap concentration causing 100% mortality in adult wasps 24 h after treatment was 17.5 g L(-1). The LC(50) was 2.75 g L(-1). Soap did not have any effect on the survival of parasitoid immatures or on the fitness or number of eggs produced per female parasitoid. Wasps that were in contact with treated aphids did not oviposit as much in them as in untreated aphids, indicating that female parasitoids detected aphids treated with insecticidal soap. CONCLUSION: These data suggest that aphid parasitoids released following treatment with insecticidal soap are likely to accept a lower proportion of the surviving aphids. Biological control programmes could be ameliorated by soap applications if the latter were made 1 day before the release of wasps in the greenhouse.     

The action of phosphine against the eggs of phosphine-resistant and -susceptible strains of Rhyzopertha dominica F

The effect of phosphine at exposure periods of 24, 48 and 120 h on hatching and mortality of 0- to 1-day-old eggs of susceptible (TN6) and resistant (FC10) strains of Rhyzopertha dominica of field origin was investigated. The fumigant affected hatching in both the strains. In a 48-h exposure at 27 (+/- 2) degrees C, the LD99 doses for the eggs of TN6 and FC10 were 0.56 and 3.25 mg litre-1, respectively. Significant reduction in hatching was observed in treated batches with progressive increase of phosphine dose in the first 2-3 days. On subsequent days the numbers hatching were often similar to those in controls, and sometimes exceeded control hatch, especially following a 5-day exposure. A critical change in the order of susceptibility of egg and adult stages of the two strains was noticed. In 48-h exposures, eggs of the susceptible strain were more tolerant than their adults, whilst the reverse was true in the resistant strain.     

大灰食蚜蝇成虫饲养研究

实验室内用蜂花粉、花粉健美酥、10％蜂蜜水及10％蔗糖水饲养大灰食蚜蝇成虫时,证明大灰食蚜蝇的产卵量、卵的孵化率及成虫寿命均受补充营养物的影响。以蜂花粉饲养的效果为最佳,平均产卵量为970.7粒(最高2212粒),孵化率达91.4％,雌雄成虫寿命分别为19.4和17.4天。交尾次数、产卵时期对卵的孵化率均无影响。为使成虫正常产卵,除合适的补充营养外,提供蚜虫及其寄主植物也是必要的。     

二点委夜蛾形态特征及生物学特性

二点委夜蛾是近年来我国夏玉米上发现的一种新害虫,目前在我国玉米产区有加重为害和成灾的趋势。为便于田间准确识别该虫、调查其发生为害规律以及掌握其主要生物学特性,在室内对二点委夜蛾不同发育阶段的形态特征和主要生物学特性进行了系统观测。结果表明,在温度为(26±1)℃、相对湿度70%左右、光周期L14 h∥D10 h、人工饲料饲养条件下,二点委夜蛾卵期平均为4.25 d;幼虫一般为5龄,幼虫期平均为18.28 d;蛹期平均为7.69 d,蛹重平均可达75.77 mg;成虫产卵前期平均为3.29 d,产卵可持续9.13d,平均每雌产卵量为305.3粒,最多产500粒,最少132粒。雌雄蛾平均寿命分别为14.75 d和18.88 d。整个世代发育历期约为33.35 d。     

The toxic effect of diflubenzuron on Spodoptera littoralis eggs and on their respiration

The mortality rates of Spodoptera littoralis eggs of different ages when dipped in aqueous dilutions of a liquid diflubenzuron formulation were investigated. Eggs 2-3 days old were less sensitive than younger eggs, 0-1 day old. The respiratory rate of eggs 0-1 day old, 1 or 2 days after treatment, was the same as in the control. Eggs in the control hatched on the next day; on this day, respiration in the treated eggs decreased rapidly, but further decrease was then gradual and the base line was not reached until 11 days after treatment, or 9 days after the maximum respiratory rate had been obtained. The curve with diflubenzuron resembled that obtained with parathion.     

日本刀角瓢虫形态特征及生物学特性研究

日本刀角瓢虫是粉虱类害虫的重要捕食性天敌之一、本文详细地描述了日本刀角瓢虫的形态特征，并附有各虫态的特征图。且对日本刀角瓢虫的生活习性进行了观察、以烟粉虱卵为食料，日本刀角瓢虫世代发育历期平均为22．56天，成虫平均寿命为9l94天，平均每雌产卵量为564．8粒：以烟粉虱若虫为食料，日本刀角虫世代发育历期平均为21．70天，成虫平均寿命为81．62天，平均每雌产卵量为650．0粒：瓢虫可捕食烟粉虱的卵、若虫、“蛹”、成虫各虫态，是烟粉虱的有效天敌，具有很好的保护利用价值。     

补充营养对草地贪夜蛾成虫存活和繁殖的影响

草地贪夜蛾Spodoptera frugiperda（Smith）是一种远距离迁飞害虫,其成虫生存期间会取食,但是取食获得的水和糖在其交配繁殖中的作用目前并不清楚。本研究利用卵巢解剖法和行为观察法,详细研究了成虫喂食对草地贪夜蛾存活、卵巢发育和繁殖的影响。发现饥饿不喂食草地贪夜蛾成蛾存活时间短（约3 d）,卵巢发育不成熟（低于2级）、交配率低（22.00%）、几乎不产卵（5.8枚）,卵几乎不孵化（3.0%）。喂食纯水或蜂蜜水成蛾存活时间长（6~8 d）,雌蛾卵巢发育成熟（3.4~3.6级）、交配率高（61.1%~66.7%）、产卵量大（436~1281枚）、卵孵化率高（大于95%）,均显著大于不喂食成蛾。喂食对交配雌蛾的交配次数（1.1~1.7次）和未发育成熟雌蛾的交配率（18.2%~22.9%）无显著影响。喂食蜂蜜水雌蛾的存活时间（8.06 d）和产卵量（1281枚）显著大于喂食纯水（分别为6.57d和436枚）,而雄蛾存活时间、雌蛾卵巢发育等级、交配率、卵孵化率在喂食纯水和蜂蜜水之间无显著差异。本研究结果认为水是草地贪夜蛾成蛾存活和繁殖必须补充的物质,糖仅能增加雌蛾的产卵量。仅仅利用花香气味进行草地贪夜蛾的监测和防控,效果可能不理想。这些结果为草地贪夜蛾的精准监测和有效防控提供理论依据。     

东方钝绥螨生物学及食量研究

东方钝绥螨在昌黎地区每年大约发生23代左右。平均卵期1.8天,幼虫期0.7天、第一若虫期1.0天、第二若虫期1.5天、产卵前期4.6天、产卵期15.2天、雌成螨期20.5天、雄成螨期15.6天、生命周期为25.5天。平均日产卵量1.5粒,总卵量16粒。雌成螨日捕食山楂叶螨卵3粒及若螨0.46头,总捕食量为卵91粒,若螨43头及成山楂叶螨14头,对苹果全爪螨捕食量3.4头(雌成螨)。     

Evaluating Pochonia chlamydosporia in a double-cropping system of lettuce and tomato in plastic houses infested with Meloidogyne javanica

The effect of Pochonia chlamydosporia , a facultative fungal parasite of nematode eggs, alone or in combination with oxamyl was evaluated in a double-cropping system of lettuce and tomato in unheated plastic houses infested with Meloidogyne javanica at two sites for two consecutive growing seasons. An additional treatment of methyl bromide fumigation was included to compare crop yield in nematode-free vs. nematode-infested soil. Final population densities, reproductive rate, root gall rating, and egg production were determined after each crop. Pochonia chlamydosporia was isolated from nematode eggs up to nine months after application to soil. The fungus survived in the rhizosphere for the entire growing season at one site, but only at low densities. Final population densities of M. javanica decreased after cultivation of lettuce and increased after tomato, and this pattern of population fluctuation was unaffected by treatment, experiment or site. The reproductive rate on lettuce was equal to or below 1, and it was similar among treatments in both experiments at both sites. Eggs were not found on lettuce roots. On tomato, the reproductive rate in the fungus + oxamyl treatment was significantly lower ( P  < 0·05) than other treatments in experiment 1 at both sites. Fungus + oxamyl consistently reduced root gall ratings on tomato in all cases, but numbers of eggs per g root varied depending on treatment. Methyl bromide-treated plots remained free of M. javanica at the end of the 2-year study.     

拟澳洲赤眼蜂对小菜蛾卵的适应能力

本文比较经米蛾卵繁殖的拟澳洲赤眼蜂在小菜蛾卵和米蛾卵上的产卵差别，结果为：不喂蜜糖水，拟澳洲赤眼蜂寿命短，不到一天，可在小菜蛾卵上产卵的雌蜂比 只有４５．４５％，比可在米蛾卵上产卵的雌蜂比例低得多，可产卵雌蜂的平均产卵量亦是在小菜蛾卵上的低，喂以蜜糖水，拟澳洲赤眼寿命得以延长，平均寿命达１２天以上，可在小菜蛾卵上产卵的雌蜂比例为９６．１３％，与可在米蛾卵上产卵的雌蜂比例相当，并且在两种寄主卵上可产     

Uptake of DDT and DDE by the quail embryo and chick

Adult female Japanese quail (Coturnix coturnix japonica) were dosed orally with pp'-DDT in order to produce residues of pp'-DDT and pp'-DDE in their eggs. Eggs were incubated and insecticide uptake by the developing embryos and chicks was compared with the results of other authors, who had injected chicken eggs with insecticide solution before incubation. Rate of uptake by quail embryos increased throughout the incubation period. At hatching and 2 days after hatching, the yolk sac was estimated to contain mean amounts of 37% and 7%, respectively, of the total residues in the chick. Quail eggs, without detectable organochlorine residues, were injected with either pp'-DDT or pp'-DDE in olive oil. At 6 days incubation significantly more DDE than DDT was found in the embryo, but this trend had stopped by 10 days incubation. Metabolism of pp'-DDT to pp'DDE was first detected after 9 days incubation. Embryonic development was slower in injected eggs than in eggs from treated females.     

三种杀螨剂对山楂叶螨的毒力评价

为筛选出高效防治山楂叶螨Amphitetranychus viennensis Zacher的杀螨剂,利用玻片浸渍法和叶片残毒法测定了3种杀螨剂对其3种螨态的室内毒力,并对不同浓度杀螨剂的田间防效进行了测定。结果表明:240 g/L螺螨酯、110 g/L乙螨唑和43%联苯肼酯中仅联苯肼酯对山楂叶螨雌成螨有毒力,其LC50为37.65 mg/L;3种杀螨剂均能毒杀卵及幼螨,毒力大小依次为乙螨唑联苯肼酯螺螨酯;同一杀螨剂对幼螨的毒力均高于对卵的毒力。240 g/L螺螨酯和110 g/L乙螨唑对山楂叶螨的总体防效较好,除螺螨酯4 000倍液处理的防效在药后30 d达到最大97.11%外,其余各处理均在药后15 d达到最大,防效为88.76%~96.14%;但二者速效性较差,药后1~7 d防效均低于对照;而螺螨酯4 000、5 000倍液处理及乙螨唑5 000倍液处理的持效性较好,药后30 d防效仍有97.11%、90.90%和93.06%,均显著高于对照。43%联苯肼酯对山楂叶螨的总体防效在3种杀螨剂中最高,其1 800、2 500倍液处理分别在药后7 d和3 d时防效达到最大99.79%和98.64%;1~7 d防效为97.45%~99.79%,显著高于其余杀螨剂和对照;30 d时防效分别达98.14%和96.19%,速效性和持效性均较好。表明螺螨酯和乙螨唑对山楂叶螨的持效性较好,联苯肼酯则有良好的速效性和持效性,可以按照其不同特点推广应用。