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。     

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     

宁波地区烟粉虱及其寄生蜂调查

烟粉虱Bemisia tabaci(Gennadius)是重要的世界性害虫之一,对农业生产造成了严重的危害.利用天敌对烟粉虱进行生物防治已经成为研究重点.本文于2007年6月至2008年11月对宁波地区不同寄主作物上烟粉虱虫口数量及其寄生蜂种类进行了调查.结果查得烟粉虱寄生蜂共7种,它们是恩蚜小蜂属Encarsm Forster的浅黄恩蚜小蜂En.sophia、日本恩蚜小蜂En.japonica、丽蚜小蜂En.formosa、黄盾恩蚜小蜂En.smithi和桨角蚜小蜂属Eretmocerus Haldeman的蒙氏桨角蚜小蜂Er.mundus、狄氏桨角蚜小蜂Er.debachi、盾黑桨角蚜小蜂Er.melanoscutus,其中优势种为浅黄恩蚜小蜂En.sophia、蒙氏桨角蚜小蜂Er.mundus和狄氏桨角蚜小蜂Er.debachi,这3种寄生蜂分别占收集到寄生蜂总数量的35.89%、49.66%和11.01%;此外,田间十字花科蔬菜上的烟粉虱虫13数量最高峰在2007年12月,自然寄生率最高峰在2008年10月,寄生率可达到13.86%;田间黄瓜上的烟粉虱虫口数量最高峰出现在2007年11月,自然寄生率最高峰在2007年8月,寄生率可达到8.22%;田间茄子上的烟粉虱虫口数量高峰出现在2007年7月和9月及2008年10月,自然寄生率高峰出现在2007年7月和9月及2008年9月,分别达到13.25%,10.30%和5.92%.     

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。     

利用黄板监测烟粉虱及其寄生蜂的种群动态

研究了黄板不同放置高度、不同时间内对日光棚室内番茄上烟粉虱Bemisia tabaci(Gennadius)及其寄生蜂种群的诱集监测效果。结果表明,在同一时间内以黄板上部与植株顶部持平的高度悬挂的黄板对烟粉虱和蚜小蜂的诱集效果最好,其次是以黄板上部与植株中部持平的高度悬挂的黄板,当黄板的底部高出植株顶部30 cm时对烟粉虱及其蚜小蜂的诱集效果最差。在5~10月份,随着季节的变化,同一位置的黄板对烟粉虱及蚜小蜂的诱集数量逐渐增加。调查发现,番茄上烟粉虱的寄生蜂主要为桨角蚜小蜂属EretmocerusHaldeman和恩蚜小蜂属EncarsiaF erster,2个属的蚜小蜂在季节上呈互补之势,因此总体上蚜小蜂对烟粉虱的寄生率在5~10月之间呈不断上升的趋势。     

海氏桨角蚜小蜂对不同龄期“Q”烟粉虱的取食和寄生反应

【背景】近年来＂Q＂烟粉虱在我国快速扩张,已成为农业生产上的一种重要入侵害虫。由于化学农药的大量使用,＂Q＂烟粉虱已对多种农药产生高抗药性,保护和利用天敌昆虫对其进行控制具有重要意义。【方法】本文在室内研究了近年引入我国的海氏桨角蚜小蜂对不同龄期＂Q＂烟粉虱若虫的取食和寄生能力。【结果】各龄期的＂Q＂烟粉虱若虫均可被海氏桨角蚜小蜂取食和寄生。在48h内,寄生蜂取食1、2、3、4龄烟粉虱若虫的数量分别为10.7、6.4、6.7、5.0头,呈现随龄期增大取食数量下降的趋势;海氏桨角蚜小蜂对不同龄期烟粉虱若虫的寄生能力存在明显差异,其更偏好寄生2、3龄若虫（25.4和27.5头）,其次是1龄若虫（22.1头）,而寄生4龄粉虱的数量最低（16.5头）。【结论与意义】寄主龄期对海氏桨角蚜小蜂的取食和寄生能力具有显著影响。综合来看,该寄生蜂表现出对＂Q＂烟粉虱较好的生物防治潜能,是防治烟粉虱的理想寄生性天敌昆虫。     

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.     

烟粉虱及海氏桨角蚜小蜂对中国番茄黄化曲叶病毒感染烟草的嗅觉反应

双生病毒可通过调控寄主植物促进媒介昆虫烟粉虱种群增长,然而病毒侵染植物后是否通过调控植物挥发物来影响烟粉虱及其天敌的嗅觉反应还未见报道。【目的】本文旨在研究烟草植株感染中国番茄黄化曲叶病毒(Tomato yellow leaf curl China virus,TYLCCNV)后对烟粉虱Bemisia tabaci(Gennadius)及其重要寄生性天敌海氏桨角蚜小蜂Eretmocerus hayati(Zolnerowich and Rose)嗅觉反应行为的影响。【方法】利用Y形嗅觉仪方法,我们测试了烟粉虱及海氏桨角蚜小蜂对带毒植株、健康植株及烟粉虱危害植株的选择偏好性。【结果】烟粉虱及海氏桨角蚜小蜂选择携带TYLCCNV病毒的烟草显著多于健康烟草植株,但烟草被病毒与烟粉虱共同侵染时,烟粉虱对带毒烟草的选择仍显著多于无毒植株,而寄生蜂虽然仍较多选择带毒植株,但无显著差异。【结论】这些结果表明烟粉虱及海氏桨角蚜小蜂偏好选择携带TYLCCNV病毒的烟草,但这种偏好作用在烟粉虱取食共同危害时有一定程度的减弱。本研究首次报道了双生病毒侵染植物可增加烟粉虱及其天敌对植物的选择作用,并就其功能及机制进行了讨论。     

天津地区寄生烟粉虱的桨角蚜小蜂分子鉴定和遗传多样性分析

挖掘本土天敌资源是害虫生物防治的有效手段。桨角蚜小蜂Eretmocerus spp.是烟粉虱Bemisia tabaci重要的寄生性天敌之一,明确桨角蚜小蜂本地种类及遗传分化关系,对本土天敌资源挖掘具有重要意义。本研究在天津5个地区采集了13个地理、寄主的桨角蚜小蜂种群,利用线粒体mtDNA COI基因片段作为分子标记,进一步通过MEGAX、DnaSP 5.10等软件进行遗传分化分析。结果表明,本研究所采种群中包含2种桨角蚜小蜂,其中测得蒙氏桨角蚜小蜂Eretmocerus mundus mtDNA COI基因序列20条（755 bq）,未命名桨角蚜小蜂Eretmocerus sp. WTT-2016 mtDNA COI基因序列20条（739 bq）。两种桨角蚜小蜂的遗传多样性均较低,其中蒙氏桨角蚜小蜂Hd = 0.368,Pi = 0.00557,K = 4.205;未命名桨角蚜小蜂Hd = 0.616,Pi = 0.00106,K = 0.784。错配分析表明,蒙氏桨角蚜小蜂在天津种群较稳定,近年来未出现扩张现象。     

Seasonal occurrence of key arthropod pests and associated natural enemies in Alabama Satsuma citrus

Six Alabama Satsuma mandarin orchards (four conventionally sprayed and two unsprayed) were surveyed during 2005 and 2006 to determine the population dynamics of arthropod pests and their natural enemies. Twenty-eight arthropod pest species were encountered; the major foliage pests were citrus whitefly, Dialeurodes citri (Ashmead); purple scale, Lepidosaphes beckii (Newman); Glover scale, L. gloveri (Packard); and citrus red mite, Panonychus citri (McGregor). Two distinct population peaks were recorded for citrus whitefly at most locations. The most important direct sources of citrus whitefly mortality were parasitism by Encarsia lahorensis (Howard) and infection by the pathogenic fungus, Aschersonia aleyrodis Webber. In general, all stages of both scale insects (purple scale and Glover scale) were present in the orchards year-round, indicative of overlapping generations; however, the highest densities were recorded during the early season. Citrus whitefly, purple scale, and Glover scale were more abundant on leaves collected from the interior of the tree canopy than in the exterior canopy. Citrus red mite densities were highest in the spring, with populations declining at the start of the summer, and were more abundant in the exterior canopy than in the interior canopy. The most important natural enemies of citrus red mite were predatory mites belonging to several families, of which Typhlodromalus peregrinus Muma (Phytoseiidae) was the predominant species. Major differences were recorded in the relative abundance of different arthropod pest species in the orchards: citrus whitefly, purple scale, and Glover scale predominated in the unsprayed orchards, whereas citrus red mite infestations were more severe in the sprayed orchards. The results are discussed in relation to the possible effect of orchard management practices on abundance of the major pests.     

Augmentation and evaluation of a parasitoid,Encarsia inaron,and a predator,Clitostethus arcuatus,for biological control of the pomegranate whitefly,Siphoninus phillyreae

The aim of this study was to evaluate the biological control potential of Encarsia inaron (Walker) (Hymenoptera: Aphelinidae) and a predator Clitostethus arcuatus (Rossi) (Coleoptera: Coccinellidae) against the pomegranate whitefly, Siphoninus phillyreae (Haliday) (Homoptera: Aleyrodidae) on pomegranate (Punica granatum L.) by mass rearing and augmentative releases of these two natural enemies during a long-term field study in Egypt. A study was conducted to evaluate the biological control potential of this pest by augmentation with a parasitoid, En. inaron, and a predator, C. arcuatus. Both species were mass reared and monthly releases were made in fields of pomegranate during each of 11 consecutive years (1996–2006). About 1,155,000 En. inaron and 990,000 C. arcuatus were released in fields in Assuit governorate in Egypt on pomegranate which was naturally infested by S. phillyreae. Populations of the natural enemies and parasitism were much higher in field plots where releases were made compared with where no releases were made. The maximum rate of parasitism reached 93% (88% by En. inaron) in the field treatment where releases were made, while parasitism peaked at 36% where no releases were made. The population of En. inaron was significantly correlated with the population of whitefly during the field season. Additional parasitism was by natural infestation with Eretmocerus parasiphonini Evans and Abd-Rabou (Hyneoptera: Aphelinidae). Among all years, the maximum number of C. arcuatus ranged from 13 to 44 beetles per 100 leaves for the treatment, and there were more predators in the release plot than in the control plot. These observations enhance understanding of the usefulness of these natural enemies after augmentation in the field.     

Naturally occurring populations of Bemisia tabaci, biotype B and associated natural enemies in agro-ecosystem in northern China

The sweet potato whitefly, Bemisia tabaci (Gennadius) biotype B was first found in southern China in 1994 and has since then become a pest of increasing importance throughout the nation. The population dynamics of this invasive species and the effect of natural enemies on its population dynamics were studied in commercial cotton fields during the summers of 2003 through 2005 in Langfang, Hebei (northern China). The abundance of Bemisia tabaci was found to increase rapidly in late July, and reached its first peak in mid-August, then followed by the second peak in early September. Whitefly populations subsequently declined slowly to attain a plateau after mid-September. A total of 13 natural enemy species were discovered in association with B. tabaci in cotton fields, including dominant species such as Chrysopa sinica Tjeder, Leis axyridis Pallas, Propylaea japonica Thunberg, Orius similis Zheng, and Eretmocerus sp. Caged experiments on velvetleaf, Abutilon theophrasti Medic, one of the preferred host plants of the insect, indicated higher B. tabaci population densities in small-mesh cages with exclusion of all natural enemies versus those in medium- and large-mesh cages, and the uncaged plants retained the lowest population densities of B. tabaci. While no natural enemies were observed in the small-mesh cages, natural enemies like Misumenopos tricuspiaata, Eretmocerus sp., Encarsia formosa Orius similis, Deraeocoris punctulatus and Scolothrips takahashii were found in medium- and/or large-mesh cages. Findings from this study suggest that under open-field conditions, various indigenous natural enemies of different sizes may act in concert in the suppression of B. tabaci populations.     

Chlorpyrifos spraying of no-tillage corn during tasselling and its effect on damage by Helicoverpa zea (Lep., Noctuidae) and on its natural enemies

Abstract:  Corn plants were twice sprayed at 3-day intervals during tasselling to evaluate the effect of chlorpyrifos on ear damage by H . zea and also on the populations of the natural enemies associated with this moth. The abundance of H . zea eggs and larvae and of predators on the whole plant, the egg parasitism by Trichogramma pretiosum Riley and the percentage of injured ears were sampled weekly. Chlorpyrifos did not show any significant effect on population levels and on ear damage by H . zea . Natural parasitism of eggs ranged from 52 to 75% and did not differ between treated and untreated plots; furthermore, the percentage of non viable eggs and adult emergence were not influenced by insecticide application. Among the predators found in the plots, Doru luteipes was not affected by spraying, whereas the abundance of Orius sp. decreased 21 days after insecticide application. The frequency of the ant Pheidole sp. was not affected by chlorpyrifos; however, foraging activity of Crematogaster sp. on treated plots was rapidly reduced and remained low during the following 2 weeks. The small number of damaged ears suggests that the insecticide did not affect the efficiency of the natural enemies of H . zea .     

Yellow sticky trap catches of parasitoids of Bemisia tabaci (Hemiptera: Aleyrodidae) in vegetable crops and their relationship to in-field populations

We examined the relationship of yellow sticky trap captures of Bemisia tabaci (Gennadius) biotype B parasitoids to the local population of parasitoids as measured by leaf samples of parasitized whiteflies and mass release of parasitoids. Traps were placed in experimental collard and cowpea field plots in Charleston, SC, and in commercial organic fields of spring cantaloupe and watermelon in the Imperial Valley, CA. The exotic parasitoid Eretmocerus emiratus Zolnerowich and Rose was released in Imperial Valley fields to ensure parasitoid populations would be present. Bemisia adults were trapped in the greatest numbers on the upper surface of horizontally oriented sticky traps in melon fields. In contrast, the lower trap surfaces consistently captured more Eretmocerus than upper surfaces. Female parasitoids were trapped in greater numbers than males, especially on the lower trap surfaces. Progeny of released exotic Eretmocerus greatly outnumbered native E. eremicus Rose and Zolnerowich and Encarsia spp. on traps. Throughout the season, the trend of increasing numbers of Eretmocerus on traps parallelled the increase in numbers of whiteflies. Over the season, 23-84% of all B. tabaci fourth instars were visibly parasitized by Eretmocerus. The numbers of Eretmocerus caught by traps in cantaloupe were similar in trend to numbers on leaf samples in melons, but not with those in watermelon, where whitefly populations were lower. Parasitoid numbers were low in collard and cowpea samples, and no trend was observed in numbers of parasitoids captured on traps and numbers on leaves for these two crops. Overall, there were no significant correlations between sticky trap catches of parasitoids and numbers of parasitized whiteflies on leaf samples in any test fields. Nevertheless, sticky traps placed within crops may be useful for observing trends in whitefly parasitoid populations at a particular site and for detecting parasitoids at specific locations.     

Role of the aphelinid parasitoid Encarsia guadeloupae in the suppression of the exotic spiralling whitefly Aleurodicus dispersus on banana in India

A field study conducted during 2000-2001 on banana plantation located at Bangalore Rural district revealed that the population of the spiralling whitefly Aleurodicus dispersus Russell declined from 116.85 per 25-cm² leaf area in March 2000 to 1.10 per 25-cm² leaf area in December 2001. During the study period, a total of seven natural enemies were observed. The aphelinid parasitoid Encarsia guadeloupae Viggiani was the only major natural enemy encountered on the spiralling whitefly causing 20.70% parasitism in January 2000, which had increased to 95.68% by December 2001. The density of the spiralling whitefly was positively correlated with maximum temperature and negatively correlated with relative humidity and the parasitism by E. guadeloupae. The multiple regression model showed that about 67.94% of the variation in the whitefly density could be accounted for by parasitism only.     

Interspecific Interactions among Natural Enemies ofBemisiain an Inundative Biological Control Program

Interspecific interactions among insect natural enemies have seldom been investigated experimentally within the context of biological control. Research in this area is needed due to the often contradictory predictions provided by the many theoretical models, the increasing dependence on biological control, and the concern that biological control agents may adversely affect some nontarget organisms. We describe a study whereby the occurrence and dynamics of interspecific interactions among three natural enemies (two parasitoids:Encarsia formosaandEncarsia pergandiella;and one predatorDelphastus pusillus) of the whitefly,Bemisia argentifolii(previously referred to asBemisia tabacistrain “B”), were evaluated in greenhouse cage experiments. Eight populations consisting of all possible combinations of the three natural enemies and one population of whitefly alone were established to test the following hypotheses: (1) Natural enemy introductions are capable of suppressingB. argentifoliipopulations; (2) all interspecific interactions are detrimental to achieving biological control; (3) the likelihood of achieving biological control decreases as the potential number of interspecific interactions increases; and (4) the species composition of biological control agents is of greater consequence than the number of natural enemy species released. In addition, we tested the hypothesis (5) that the frequency of interspecific interactions increases with a decrease in host or prey availability. Our results demonstrate that all combinations of natural enemies provided significant levels of whitefly suppression. While the intensities of interspecific interactions among natural enemy species were frequently positively and significantly correlated with the densities of parasitized whitefly, interspecific interactions among natural enemies were not detrimental to achieving higher levels of biological control. The composition of species released, rather than the number of species released, was of greater importance to accomplishing biological control. Releases ofD. pusillusin combination with one or both of the parasitoids provided the greatest levels of whitefly suppression. These results suggest that the types of interspecific interactions rather than the numbers of interspecific interactions among natural enemies may be important to the outcome of inundative biological control programs.     

Inundative field releases and evaluation of three predators for Bemisia tabaci (Hemiptera: Aleyrodidae) management in three vegetable crops

Abstract The sweetpotato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), is a global pest on numerous crops, including vegetables. Weekly inundative releases of a coccinellid predator (Coccinella undecimpunctata L. [Coleoptera: Coccinellidae]), a common green lacewing predator (Chrysoperla carnea Stephen [Neuroptera: Chrysopidae]), and a mirid predator (Macrolophus caliginosus[Wagner][Hemiptera: Miridae]) were independently made in three vegetable crops (cabbage [Brassica oleracea var. capitata L.], cucumber [Cucumis sativus L.], and squash [Cucurbita pepo L.]) for the management of the sweetpotato whitefly. Approximately 1 million to 2.5 million larvae or nymphs of each predator were released in the vegetable crops during 20 weeks. Whitefly populations were reduced by ≈ 25%–45% during most of the season in each crop where each predator was released. The effect of each predator was similar on whitefly population reduction. Late in the season (October) when whitefly populations were low, generally no benefit was obtained from releasing the predators. Numbers of predators recovered during sampling in all crops were greatest for C. carnea, but this corresponded with the fact that more individuals of this predator were released than any other predator in the experiment. These results help define the utility of these natural enemies for managing B. tabaci in vegetable crops.     

Pyriproxyfen controls silverleaf whitefly, Bemisia tabaci (Gennadius), biotype B (Homoptera: Aleyrodidae) (SLW) better than buprofezin in bitter melons Momordica charantia L. (Cucurbitaceae)

To improve compatibility between chemical and biological controls, the use of selective insecticides such as insect growth regulators (IGRs) is crucial. In cucurbits, the use of pyriproxyfen (an IGR) has been shown by others to be an effective method of reducing the number of sap-sucking insects, especially silverleaf whitefly, Bemisia tabaci (Gennadius) Biotype B (SLW). Therefore, we compared pyriproxyfen and buprofezin (an IGR) with that of no treatment (control) in a bitter melon crop for the control of populations of SLW and for their effects on fruit production. Pyriproxyfen controlled SLW and tended to have heavier fruits than the control treatment and reduced the abundance of nymphs and exuvia. Buprofezin showed no evidence in controlling SLW compared with the pyriproxyfen and control treatments. Neither pyriproxyfen nor buprofezin had any effect on the number of harvested fruit or overall fruit yield, but the average weight per fruit was higher than the control treatment. Pyriproxyfen was effective in controlling whitefly populations in bitter melons, and both pyriproxyfen and buprofezin may have the potential to increase yield. Their longer-term use may increase predation by natural enemies as they are species-specific and could favour build up of natural enemies of SLW. Thus, the judicious use of pyriproxyfen may provide an effective alternative to broad-spectrum insecticides in small-scale cucurbit production.