Bemisia tabaci (Homoptera: Aleyrodidae) instar effects on rate of parasitism by Eretmocerus mundus and Encarsia pergandiella (Hymenoptera: Aphelinidae)

Studies were conducted to compare preference among Bemisia tabaci Gennadius, biotype B instars for parasitization by Eretmocerus mundus Mercet and Encarsia pergandiella Howard when provided one instar only, two different instars, and four different instars simultaneously. In the single‐instar no choice treatment, Er. mundus was more successful in parasitizing the younger host instars, while En. pergandiella parasitized a greater proportion of the older instars. Similar results were observed when parasitoids were provided a choice of two instars in six different pair combinations. When all four instars were provided simultaneously, the numbers of first, second, and third instars parasitized by Er. mundus were not significantly different from each other (range 10.3–16.4%), but all were significantly higher than parasitism of fourth instar nymphs (2.1%). The highest percentage parasitization by En. pergandiella was in third instar (17.2%), and the lowest in first instar (2.8%).     

放蜂密度对桨角蚜小蜂Eretmocerus sp.控制烟粉虱效果的影响

研究了不同放蜂密度对桨角蚜小蜂Eretmocerussp .控制烟粉虱种群效果的影响。结果表明 ,按 1头、2头、3头、5头雌蜂 /株的密度释放桨角蚜小蜂 ,3周后烟粉虱种群的增长趋势指数分别为 2 4 .13、18.5 1、12 .4 1和 8.0 6 ,随着放蜂密度的增加 ,烟粉虱种群增长趋势指数逐渐减小 ,蚜小蜂寄生对烟粉虱种群增长的干扰作用控制指数分别为 0 .80 5 1、0 .6 176、0 .4 14 1和 0 .2 6 89。研究表明在生产中以 3头或 5头雌蜂 /株的密度释放桨角蚜小蜂Eretmocerussp .,对烟粉虱种群的控制效果较好     

Effects of bio-pesticides on Eretmocerus warrae (Hym., Aphelinidae), a parasitoid of Bemisia tabaci (Hom., Aleyrodidae)

The sweet potato whitefly Bemisia tabaci (WF) can be controlled by two commercial neem products, NeemAzal-T/S^® (1% azadirachtin) for foliar application, and NeemAzal-U (17% azadirachtin) for soil application, alongwith two biorational products of microbial origin, Abamectin (avermectin) and Success^® (spinosad). Side effects of these products were tested in a laboratory bioassay against a native aphelinid, Eretmocerus warrae (EW). Eggs and early larval instars of the parasitoid, commonly found outside the host body, were highly susceptible to foliar spray of neem with only 8%, 18% and 55% emergences of adults from treated eggs. larval and pupal stages respectively at recommended dose-rates of 5 ml/l and 1%, 8% and 40% at twice recommend dose-rate (10 ml/l). Soil application with NeemAzal-U marginally affected EW. At highest tested dose-rate of 3.0 g/l, 46%, 64% and 81% emergence was recorded after treatement of plants harbouring WF parasitized by egg, larval and pupal stages of EW respectively. In contrast to neem application, Success^® and Abamectin caused high mortality in development stages of the parasitoids. In particular, abamectin was highly toxic to the parasitoids with less than 1% emergence from either of the three development stages if treated with 1–2 ml/l.     

两种蚜小蜂对烟粉虱寄主的产卵选择性(英文)

双斑恩蚜小蜂和桨角蚜小蜂是华南地区烟粉虱的两种优势种寄生蜂。本文研究了两种寄生蜂对不同龄期烟粉虱寄主的产卵选择特性。结果表明:两种寄生蜂均可寄生烟粉虱的1~4龄若虫。当只有1个龄期的烟粉虱若虫存在时,双斑恩蚜小蜂更多地寄生3龄和4龄若虫,较少寄生1龄和2龄若虫;而桨角蚜小蜂则更多地寄生3龄和2龄若虫,较少寄生1龄和4龄若虫。在4个龄期若虫同时存在时,双斑恩蚜小蜂会明显增加对3龄和4龄若虫的产卵寄生,降低对1龄和2龄若虫的寄生;而桨角蚜小蜂则增加对2龄和3龄若虫的寄生,减少对1龄和4龄若虫的寄生。寄主植物的差异不影响这二种蚜小蜂对各龄期烟粉虱若虫的产卵选择倾向。结果提示,烟粉虱若虫3龄和4龄是双斑恩蚜小蜂最适宜的寄主,而桨角蚜小蜂最适宜的寄主是烟粉虱2龄和3龄若虫。     

两种蚜小蜂对烟粉虱寄主的产卵选择性（英文）

双斑恩蚜小蜂和桨角蚜小蜂是华南地区烟粉虱的两种优势种寄生蜂。本文研究了两种寄生蜂对不同龄期烟粉虱寄主的产卵选择特性。结果表明: 两种寄生蜂均可寄生烟粉虱的1～4龄若虫。当只有1个龄期的烟粉虱若虫存在时,双斑恩蚜小蜂更多地寄生3龄和4龄若虫,较少寄生1龄和2龄若虫;而桨角蚜小蜂则更多地寄生3龄和2龄若虫,较少寄生1龄和4龄若虫。在4个龄期若虫同时存在时,双斑恩蚜小蜂会明显增加对3龄和4龄若虫的产卵寄生,降低对1龄和2龄若虫的寄生;而桨角蚜小蜂则增加对2龄和3龄若虫的寄生,减少对1龄和4龄若虫的寄生。寄主植物的差异不影响这二种蚜小蜂对各龄期烟粉虱若虫的产卵选择倾向。结果提示,烟粉虱若虫3龄和4龄是双斑恩蚜小蜂最适宜的寄主,而桨角蚜小蜂最适宜的寄主是烟粉虱2龄和3龄若虫。     

国内烟粉虱B生物型的分布及其控制措施研究

收集了国内 15个省 2 6个不同地区的烟粉虱种群 ,根据有关报道合成了一个随即引物H16 ,对不同地区的烟粉虱DNA进行了RAPD -PCR扩增 ,根据扩增结果分析了不同烟粉虱种群的生物型。结果表明 ,在以上不同省市和地区中 ,北京、山东等 11个省 19个地区都有烟粉虱B型的分布。以烟粉虱B型为防治对象 ,比较了使用高效氯氰菊酯、高效大功臣 2种化学农药 ,和应用桨角蚜小蜂、粉虱座壳孢 2种寄生性天敌 ,对黄瓜上烟粉虱种群的控制效果 ,结果表明在一个世代内 ,喷施高效大功臣 (10 0 0× ,1次 ) ,喷施粉虱座壳孢 (5× 10 6 个孢子 /ml,2次 ) ,和释放桨角蚜小蜂 (3头雌蜂 /株 ,2次 ) ,对烟粉虱种群的控制作用分别达到 78.2 1%、95 .74 %和 5 7.5 8% ,三者都可以对烟粉虱起到较好的防治效果。     

烟粉虱生物型对浅黄恩蚜小蜂寄主选择及个体发育的影响

为探讨寄生蜂在Q型烟粉虱Bemisia tabaci替代B型烟粉虱的过程中是否起作用, 我们在实验室条件(温度27±1℃, 光周期16L∶8D, 相对湿度RH 70%～80%)下, 观察了浅黄恩蚜小蜂Encarsia sophia寄生B型和Q型烟粉虱若虫的行为, 研究了浅黄恩蚜小蜂对B型和Q型烟粉虱若虫的选择性、 烟粉虱生物型对浅黄恩蚜小蜂取食数量及个体发育的影响。结果发现, 浅黄恩蚜小蜂体外检测时间在B型和Q型烟粉虱若虫间差异不显著, 而寄生Q型烟粉虱若虫时的体内检测和产卵时间(190.2±14.6 s）显著高于寄生B型时所用时间(140.0±7.5 s)。在非选择条件下, 浅黄恩蚜小蜂寄生B型烟粉虱若虫的数量(8.1±0.5头)及总产卵量（9.3±0.6粒）显著高于仅提供Q型烟粉虱的寄生数量(6.3±0.5头)及总产卵量(7.0±0.6粒); 而被寄生若虫单头着卵量在处理间差异不显著。在选择性条件下, 该蜂寄生B型烟粉虱若虫量(3.1±0.4头)、总产卵量(3.8±0.5粒)及被寄生若虫单头着卵量(1.2±0.1粒)都显著高于寄生Q型烟粉虱时的情况(1.8±0.3头、1.8±0.4粒、0.7±0.1粒)。被寄生蜂取食的B型与Q型烟粉虱数量间差异不显著, 但对于同一生物型而言, 交配过的雌蜂能够取食更多的烟粉虱若虫。以B型烟粉虱为寄主时, 浅黄恩蚜小蜂雌蜂卵-黑蛹(7.2±0.1 d)、黑蛹-羽化(5.2±0.1 d)的发育时间与以Q型烟粉虱若虫为寄主时的相应发育时间(7.3±0.1 d, 5.6±0.1 d)间无显著性差异。以B型烟粉虱为寄主时寄生蜂的羽化率（73.55%±1.42%）与以Q型烟粉虱为寄主时的羽化率（68.42%±13.01%）间差异不显著。这些结果表明, 虽然浅黄恩蚜小蜂发育时间、 羽化率在烟粉虱2种生物型间无显著差异, 但该小蜂倾向于B型烟粉虱若虫作为寄主, 而且, 以B型烟粉虱若虫为寄主时, 小蜂的产卵量和寄生若虫数量均增加。但田间浅黄恩蚜小蜂的存在是否有助于Q型烟粉虱成为B型和Q型混合种群的优势种群, 还需进一步研究。     

Development and reproduction of ‘B＇ biotype Bemisia tabaci （Gennadius） （Homoptera： Aleyrodidae） on four ornamentals

Abstract Effects of four commercial ornamentals on the development, survivorship and reproduction of the whitefly B biotype Bemisia tabaci (Gennadius) were studied in the laboratory (temperature 26 ± 1 °C; relative humidity 75%–90%; L: D 14:10). The total survivorship from egg to adult on hibiscus ( Hibiscus rosa-sinensis L.), poinsettia ( Euphorbia pulcherrima Will), cottonrose hibiscus ( Hibiscus mutabilis L.) and variegated leafcroton ( Codiaeum variegatum'Aucubaefolium' ) were 33.69%, 40.55%, 79.11%, and 29.39%, respectively. The developmental periods from egg to adult varied from 23.12 days on cottonrose hibiscus to 32.13 days on hibiscus. The average longevity of adult females ranged from 6.87 days on variegated leafcroton to 21.07 days on poinsettia. The average numbers of eggs laid per female were 9.20, 25.13, 54.45, and 26.79 on the above respective hosts. The intrinsic rates of natural increase ( r_m ) for B biotype B. tabaci on cottonrose hibiscus was the highest. Based on life table analyses of whitefly populations, cottonrose hibiscus was the most suitable host for B biotype B. tabaci in this study.     

氟吡呋喃酮对蒙氏桨角蚜小蜂生物学及温室种群动态的影响

氟吡呋喃酮和蒙氏桨角蚜小蜂Eretmocerus mundus均是控制烟粉虱Bemisia tabaci的有效作用因子,明确氟吡呋喃酮对蒙氏桨角蚜小蜂的作用对协调应用化学农药和生防天敌绿色防控烟粉虱有重要意义。本研究首先在室内测定了氟吡呋喃酮对蒙氏桨角蚜小蜂的亚致死浓度（LC15）和致死中浓度（LC50）,并研究了氟吡呋喃酮亚致死剂量对蒙氏桨角蚜小蜂的寿命、寄生率、发育历期和羽化率等生物学指标的影响,进一步在温室内研究了氟吡呋喃酮推荐浓度对蒙氏桨角蚜小蜂种群动态的影响。结果表明,氟吡呋喃酮对蒙氏桨角蚜小蜂亚致死浓度（LC15）和致死中浓度（LC50）分别为4.397 mg ai/L和35.1 mg ai/L,与对照相比,在两种浓度处理下蒙氏桨角蚜小蜂的寿命分别缩短39.3%和59%,发育历期分别延长5.9%和39.3%,寄生率分别减少22.5%和23.5%,羽化率分别减少4.43%和8.36%。温室试验表明,随用药时间的延长,蒙氏桨角蚜小蜂数量降低。药后3~15 d蒙氏桨角蚜小蜂种群数量减少21.7%~62.9%,显著低于对照,但用药18 d后种群下降趋势逐渐平缓,与对照处理相比差异不显著。该研究结果为协调应用氟吡呋喃酮和桨角蚜小蜂绿色防控烟粉虱提供了依据。     

Contagious sterility in the parasitoid wasp Eretmocerus mundus (Hymenoptera: Aphelinidae)

The parasitoid wasp Eretmocerus mundus (Hymenoptera: Aphelinidae) is used commercially to control the sweet potato whitefly Bemisia tabaci (Homoptera: Aleyrodidae). Recently, a rapid deterioration of E. mundus populations has been documented under mass-rearing conditions. We found that deteriorating cultures consist of increasing proportions of sterile individuals, up to 90% within 6 months. Microscopic examination revealed that the gonads of wasps from both sexes are severely underdeveloped. Preliminary screening for potential pathogen candidates by means of polymerase chain reaction and denaturating-gradient gel electrophoresis did not provide any indication of possible causative agents.     

三种杀虫剂对烟粉虱优势寄生蜂海氏桨角蚜小蜂的安全性评价

为评价噻虫嗪、阿维菌素和氟啶虫胺腈对烟粉虱优势寄生蜂海氏桨角蚜小蜂Eretmocerus hayati的安全性,采用琼脂保湿浸叶法分别测定了3种杀虫剂对烟粉虱成虫和海氏桨角蚜小蜂成蜂的室内毒力以及对海氏桨角蚜小蜂蛹羽化率的影响.结果表明,噻虫嗪、阿维菌素和氟啶虫胺腈对烟粉虱的LC50分别为453.76 mg/L、2.00 mg/L和29.47 mg/L,对海氏桨角蚜小蜂成蜂的LC50分别为0.23 mg/L、1.07 mg/L和0.64 mg/L.通过风险系数评估,表明阿维菌素对海氏桨角蚜小蜂成蜂安全,而噻虫嗪和氟啶虫胺腈对该蜂成蜂具有轻微到中度毒性.3种杀虫剂在烟粉虱和寄生蜂之间的选择性毒力指数表明噻虫嗪对海氏桨角蚜小蜂的负向选择性最强,其次是氟啶虫胺腈,阿维菌素最弱.3种杀虫剂均可显著降低海氏桨角蚜小蜂蛹的羽化率,对蛹的毒性为轻微有害,风险等级为2级.本研究结果将为烟粉虱综合治理中协调使用寄生蜂和化学药剂奠定理论基础.     

寄主作物对B型烟粉虱生长发育和种群增殖的影响

在恒温28℃、湿度80％的条件下研究了5种寄主植物对B型烟粉虱(Bemisia tubaci)生长、发育和繁殖的影响。结果表明：取食棉花、烟草、花生、大豆和玉米的烟粉虱。其形态、发育历期、存活率、成虫繁殖力和寿命等生命参数均有明显差异。棉花、大豆和玉米不利于烟粉虱卵和若虫的生长发育。表现为虫体较小、卵期和生命周期延长、存活率降低。烟粉虱在棉花、大豆、花生、烟草和玉米上的生命周期分别为32．03d、32．11d、25．69d、24．43d和20．68d。其存活率分别为49．86％、54．41％、86．86％、69．93％和29．38％。与烟草和玉米相比。棉花、大豆和花生明显有利于烟粉虱的种群繁殖．在棉花、大豆、花生、烟草和玉米上生长发育的成虫寿命和单雌产卵量分别是27．8d和235．O粒、23．2d和191．1粒、22．Od和131．1粒、6．25d和28．O粒、2．42d和5．1粒。在花生、大豆、棉花、烟草和玉米上的内禀增长率(rm)分别为O．1590、O．1364、O．1236、O．0841和-O．0285．其种群趋势指数(I)分别为113．85、117．38、103．98、19．58和O．4274。     

海氏桨角蚜小蜂对两种生物型烟粉虱的功能反应研究

本文报道海氏桨角蚜小蜂Erelmocerus hayati在室内对不同寄主密度下的B型和Q型烟粉虱Bemisiatabaei寄生和取食情况,并比较了该蜂对两种生物型烟粉虱功能反应的差异。结果表明,海氏桨角蚜小蜂对两种生物型烟粉虱的寄生率和致死率可分别达到60％和70％以上,平均每日最大致死量可达40头烟粉虱若虫。该蜂对两种生物型烟粉虱的功能反应曲线符合Holling Ⅱ型,随寄主密度的增加对烟粉虱若虫的寄生和致死数量均增加直至达到每日最大致死数量,而寄生率和致死率则随寄主密度的增加而显著下降。该蜂对两种生物型烟粉虱的功能反应没有显著的差异。     

Intraguild predation of Serangium parcesetosum (Coleoptera: Coccinellidae), on whitefly Bemisia tabaci (Homoptera: Aleyrodidae) parasitized by Eretmocerus mundus (Hymenoptera: Aphelinidae)

We studied intraguild predation of Serangium parcesetosum on Eretmocerus mundus, both natural enemies of Bemisia tabaci, on eggplant under laboratory conditions. Fourth instar and adult predators attacked parasitized and unparasitized hosts equally if immature parasitoids were larvae, but avoided predating on parasitized hosts containing pupae.     

Suitability of Bemisia tabaci (Hemiptera: Aleyrodidae) instars for the parasitization by Encarsia bimaculata and Eretmocerus sp. nr. furuhashii (Hymenoptera: Aphelinidae) on glabrous and hirsute host plants

The host instar preferences of Encarsia bimaculata and Eretmocerus sp. nr. furuhashii parasitizing Bemisia tabaci and their development on four host plants, collard, eggplant, cucumber and tomato, were studied in the laboratory. Both of the parasitoids accepted all nymphal stages of B. tabaci, but E. bimaculata preferred third and fourth instars while Er. sp. nr. furuhashii preferred second and third instars under both choice and no choice conditions. Regardless of host stage parasitized, adults of parasitoids emerged only from fourth instars. When given the simultaneous choice of all instars, E. bimaculata reduced parasitization of first and second instars (3.73 and 4.76%, respectively) while increasing parasitization of third and fourth instars (5.44 and 6.93%, respectively), in contrast Er. sp. nr. furuhashii increased its parasitization of second and third instar nymphs (1.27 and 3.17%, respectively) and decreased that of first and fourth instars (7.0 and 3.06%, respectively). Host plants did not significantly influence instar preference for either parasitoid. Developmental periods of both the parasitoids from egg to adult emergence were longest when first instars were parasitized and shortest when fourth instars were selected. Parasitoid developmental time was generally shorter on glabrous plants than on hirsute plants.     

Development and reproduction of Bemisia tabaci （Homoptera： Aleyrodidae） on three bean species

Abstract The development, survivorship and reproduction of Bemisia tabaci B-biotype on three bean species were studied at 26±1°C in the laboratory. The developmental periods from egg to adult varied from 27.80 days on garden beans to 18.20 days on soybeans. The survivorship from egg to adult on soybeans, cowpeas and garden beans was 77.14, 70.14 and 64.28%, respectively. The average longevity of female adults ranged from 12.30 days on soybeans to 9.80 days on garden beans, and the oviposition of B. tabaci varied from 160.85 eggs on soybeans to 98.00 eggs on garden beans. Life table parameters were calculated as biological attributes for Bemisia tabaci populations fed on three bean species. The results indicated that the intrinsic rate of increase (r_m), the finite rate of increase (λ) and net reproductive rate (R₀) were high for populations fed on soybeans, with values of 0.1857, 1.2041 and 82.1576, respectively. The corresponding values were less for populations fed on garden beans, with values of 0.1097, 1.1159 and 31.2661, respectively. The parametric values for cowpeas were intermediate between soybeans and garden beans but no significant difference were observed for the r_m values for soybeans and cowpeas. Experimental evidence in our investigation indicated that Bemisia tabaci is best adapted and shows the greatest preference for soybean of the three bean species tested in this study.     

B型烟粉虱与浙江非B型烟粉虱的竞争

为了了解近年来入侵中国的B型烟粉虱(Bemisiatabaci)取代本地非B型烟粉虱的潜能,在室内将一个B型与一个浙江非B型烟粉虱种群混合饲养在不同寄主植物上,跟踪观察混合种群中两个生物型个体数量相对比例的变化。结果表明,当两种生物型在棉花(Gossypiumhirsutum)上以相同初始数量共存竞争时,经过6代,非B型完全被B型替代;而在西葫芦(Cucurbitapepo)上以相同初始数量共存竞争时,只经过2代,非B型即完全被B型替代。在棉花上,即使以非B型占87%、B型占13%开始共存竞争,经过225d后,非B型也完全被B型替代。这说明B型烟粉虱具有在短期内竞争取代浙江非B型烟粉虱的能力。经分析,B型除了寄主范围比非B型的宽这一点对其竞争有利外,较强的内在竞争潜能也是其能成功入侵并替代本地非B型烟粉虱的一个重要原因。     

Effects of temperature on development,survival, longevity,and fecundity of Serangium japonicum (Coleoptera: Coccinellidae), a predator of Bemisia tabaci Gennadius (Homoptera: Aleyrodidae)

In this study, we evaluated the effect of temperature on the development and reproductive biology of Serangium japonicum (Coleoptera: Coccinellidae) at seven constant temperature regimes (17, 20, 23, 26, 29, 32 and 35°C) for its effect as a predator of Bemisia tabaci (Homoptera: Aleyrodidae). Results indicated that the duration of the egg, larval and pupal stages were significantly affected by temperature. The developmental time gradually declined with the increase of temperature from 17 to 29°C, however an extension in the developmental periods was observed in the temperature range of 32 to 35°C. The survival rates of different insect stages were stable at temperatures between 20 and 32°C; however at extreme temperatures of 35°C, a sharp decrease was evident. The highest fecundity of the female (387.2 eggs per female) was recorded at 20°C. Based on these results, life tables of S. japonicum were constructed for temperatures in the range 20–35°C. The maximum reproductive rate (R ₀=279.9) occurred at 26°C. The maximum values for innate capacity for increase (r _m=0.1131) and the finite rate of increase (λ=1.1197) occurred at 29°C. The mean generation time (T) decreased with increased temperature, the longest of which was 76.0 days (at 20°C) and the shortest was 36.6 days (at 32°C). These results offer valuable insight on the importation and establishment of S. japonicum into new environments with diverse temperature regimes.     

番茄感染双生病毒对叶毛密度和海氏桨角蚜小蜂搜寻行为及适合性的影响

植物病毒可通过影响植物形态和生理特性从而对媒介昆虫和寄生性天敌产生作用。然而, 在植物 媒介昆虫 寄生蜂三营养级关系研究中有关植物病毒的影响很少被考虑。本研究测定和分析了番茄植株感染番茄黄化曲叶病毒（tomato yellow leaf curl virus, TYLCV)后叶毛密度的变化及对烟粉虱Bemisia tabaci (Gennadius)重要寄生性天敌海氏桨角蚜小蜂Eretmocerus hayati Zolnerowich and Rose行为与适合性的影响。结果表明： 携带TYLCV病毒番茄植株叶毛密度显著增加, 为健康植株叶毛密度的1.8倍。海氏桨角蚜小蜂在带毒植株叶片上的寄主处置时间和寄主块停留时间显著长于其在健康植株叶片上的时间, 分别为其2倍和1.5倍, 但寄生蜂的寄生率、 羽化率及发育历期差异不显著(P>0.05)。本文首次报道了双生病毒侵染可引起叶毛密度的增加, 对理解植物-双生病毒-烟粉虱-寄生蜂四方关系提供了新的数据。     

寄主植物对双斑恩蚜小蜂的发育、存活和繁殖的影响

研究了茄子和扶桑两种不同寄主植物对烟粉虱寄生性天敌双斑恩蚜小蜂Encarsia bimaculata发育、存活和繁殖等特性的影响。在26±0.5℃的条件下,在扶桑上,双斑恩蚜小蜂卵至成虫的发育历期为13.6天,2龄幼虫至成虫的存活率为93.2%;而在茄子上双斑恩蚜小蜂卵至成虫的发育历期和2龄幼虫至成虫的存活率分别为12.1天和91.1％。扶桑上双斑恩蚜小蜂雌性成虫的平均寿命为8.0天,平均单雌产卵量为35.9粒;而在茄子上雌性成虫的平均寿命为6.6天,平均单雌产卵量为27.6粒。双斑恩蚜小蜂在扶桑和茄子植物上的种群内禀增长率分别为0.2081和0.892。两种不同寄主植物对双斑恩蚜小蜂在若虫发育历期和存活率、成虫寿命和平均产卵量以及内禀增长率等方面均存在着显著差异。研究结果表明,寄主植物对双斑恩蚜小蜂的发育、存活和繁殖有较大的影响。