东亚小花蝽和丽蚜小蜂对烟粉虱的协同控制效果研究

在温室内,试验观察了单独释放和组合释放东亚小花蝽Orius sauteri、丽蚜小蜂Encarsia formosa两种天敌对烟粉虱Bemisia tabaci的控制作用。结果显示：与不释放天敌的空白对照相比,单独释放东亚小花蝽处理对烟粉虱卵、若虫均有较好的控制效果;在释放后第1周, 东亚小花蝽处理及东亚小花蝽和丽蚜小蜂组合处理与对照相比对烟粉虱卵和若虫的控制效果分别达到87.1%、89.3% 和73.9%、78.3%, 两周后的控制效果分别为72.7%、6.9% 和64.8%、57.2%;而丽蚜小蜂的处理在释放天敌后第1周和第3周,对卵的控制效果分别为3.5%、80.3%,第3周对若虫的控制效果为75.7%。在相同数量天敌条件下,东亚小花蝽和丽蚜小蜂的组合处理较天敌单独处理对烟粉虱的控制效果好。     

丽蚜小蜂两个品系寄生行为及对不同寄主植物上烟粉虱的选择性

对丽蚜小蜂两个品系(分别来自北京和美国)寄生烟粉虱的行为和在番茄、黄瓜、甘蓝、茄子及棉花烟粉虱上的发育历期和寄生率进行了研究。结果表明,丽蚜小蜂通过寄主定位、寄主检查、产卵、清扫和梳理等过程对烟粉虱进行寄生,北京品系平均产卵寄生时间为5.0 m in,美国品系为4.2 m in,品系间差异显著。北京品系在棉花烟粉虱上发育历期最短,为17.4 d,甘蓝烟粉虱上发育历期最长,为20.0 d;美国品系在棉花烟粉虱上发育历期最短,为16.3 d,在其余4种寄主植物烟粉虱上发育历期较长(17.3~17.9 d)。2个品系的寄生率均表现为番茄烟粉虱上最高,分别为37.3%和39.0%;棉花次之,分别为32.2%和35.5%;黄瓜上最低,分别为30.2%和29.6%。在寄主植物选择性试验中,2个品系亦表现为寄生番茄烟粉虱时寄生率最高,美国品系为62.7%,北京品系为56.3%,寄生黄瓜烟粉虱时寄生率最低,分别为30.8%和29.0%。     

蚜小蜂和粉虱座壳孢对烟粉虱的控制作用研究

研究了烟粉虱两种寄生性天敌桨角蚜小蜂(Eretmocerus sp．)和粉虱座壳孢(Aschersonia aley-rodis)单独使用和联合使用时对烟粉虱种群的控制作用。结果表明,在单独进行控制时,在一个世代内按5×10^6个孢子·ml^-1喷施粉虱座壳孢2次,对烟粉虱种群的控制作用达95．74％,按每株植株3头雌蜂的密度释放桨角蚜小蜂2次,对烟粉虱种群的控制作用达57.58％。在两者联合控制时,一个世代内喷施粉虱座壳孢2次,再释放桨角蚜小蜂1次或2次,对烟粉虱种群的控制作用达97．02％～97．91％,烟粉虱种群增长趋势指数低于1,种群数量逐渐下降,联合使用时,桨角蚜小蜂和粉虱座壳孢间无消极影响。     

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。     

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。     

双斑恩蚜小蜂的生殖方式及其在烟粉虱体内的发育

首次对双斑恩蚜小蜂Encarsia bimaculata Heraty et Polaszek雌蜂的胚胎发育全过程进行连续观测和数码摄像,明确了双斑恩蚜小蜂的生殖方式是两性产雌,雌蜂为初寄生蜂,孤雌产雄且雄蜂为自复寄生。雌蜂在温度(25±1)℃,相对湿度70%±10%条件下,从卵到成虫的发育历期为(13.1±2.5)d,卵期(1.98±0.38)d,幼虫1龄(0.95±0.33)d,2龄(2.48±0.40)d,3龄(3.46±0.43)d,预蛹(0.95±0.20)d,蛹(4.88±0.80)d。     

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     

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.     

Interspecific interference competition between Encarsia formosa and Encarsia sophia (Hymenoptera: Aphelinidae) in parasitizing Bemisia tabaci (Hemiptera: Aleyrodidae) on five tomato varieties

Abstract Interspecific competition between Encarsia formosa and Encarsia sophia, two major parasitoids of Bemisia tabaci, and the influence of five tomato varieties on competition outcome were investigated under laboratory conditions. E. formosa parasitized more B. tabaci than E. sophia when in single wasp assays on any of the tomato varieties investigated. When B. tabaci nymphs were exposed to both wasp species (either simultaneously or sequentially), the number of B. tabaci nymphs parasitized by either wasp species was significantly decreased compared to the sole access condition. Total mortality of B. tabaci was increased when B. tabaci nymphs were exposed to both wasp species compared to only one wasp species. Thus competition between E. formosa and E. sophia apparently reduced parasitoid offspring numbers, but not the efficiency of biological control. In fact, control efficiency was enhanced in some cases, particularly on tomato variety Huangtuoyuan (HTY). When wasps were allowed sequential access to hosts, interference occurred through host feeding by the second wasp, especially if it was E. sophia. The effect of different tomato varieties was not significant.     

烟粉虱两种寄生蜂生物学特性及寄主竞争关系研究

室内比较了寄生烟粉虱Bemisia tabaci的两种寄生蜂——丽蚜小蜂Encarsia formosa和浅黄恩蚜小蜂En. sophia的生物学特性,并研究了以烟粉虱为寄主时两种寄生蜂间的竞争关系。结果表明：两者的后足胫节长度间无显著差异。浅黄恩蚜小蜂的产卵器及卵均长于丽蚜小蜂的,但浅黄恩蚜小蜂的待产卵量显著少于丽蚜小蜂。浅黄恩蚜小蜂检测寄主所花时间短于丽蚜小蜂,但检查圈数显著多于丽蚜小蜂,产卵时间以丽蚜小蜂所花时间为多。以4龄初期的烟粉虱为寄主时,丽蚜小蜂的卵期为48 h,而浅黄恩蚜小蜂24 h即完成卵期的发育。后者的蛹历期也显著短于丽蚜小蜂的蛹历期。丽蚜小蜂由卵到成虫的总发育历期比浅黄恩蚜小蜂的要长72 h左右。一头丽蚜小蜂与一头浅黄恩蚜小蜂组合后的总产卵量为14.0粒,略高于两头丽蚜小蜂组合的总产卵量（10.2粒）,显著高于两头浅黄恩蚜小蜂组合的产卵量（9.5粒）;两种蜂组合的处理中被寄生寄主体内的着卵量为1.73粒,显著高于单独一种蜂组合中被寄生寄主的着卵量,后两者分别为1.29和1.39粒。在寄主竞争情况下,在被两种蜂均寄生的寄主体内丽蚜小蜂和浅黄恩蚜小蜂产入的卵量分别为1.21和1.43粒,显著高于仅被一种蜂寄生的寄主体内的对应蜂种的卵量,后者分别为1.06和1.19粒。结果提示两种蜂均能识别对方的存在,且浅黄恩蚜小蜂表现出更强的竞争能力。     

基于SCAR标记技术的丽蚜小蜂快速识别

丽蚜小蜂Encarsia formosa Gahan作为温室粉虱Trialeurodes vaporariorum Westwood和烟粉虱Bemisia tabaci (Gennadius)等粉虱类害虫的优势寄生蜂而备受关注。针对丽蚜小蜂体型微小, 难以与其他同域近缘种寄生蜂快速、 准确区别的问题, 本研究采用SCAR (sequence characterized amplified region, 特异性扩增区域)标记技术, 筛选出一对丽蚜小蜂特征片段扩增引物(EFZZF/EFZZR), 其扩增片段的大小为287 bp。种特异性检验结果表明, 该对引物只对丽蚜小蜂的基因组DNA具有扩增能力, 对其近缘种属寄生蜂如浅黄恩蚜小蜂Encarsia sophia (Girault & Dodd)、 海氏桨角蚜小蜂Eretmocerus hayati Zolnerowich & Rose、 本地未知种桨角蚜小蜂Eretmocerus sp.、 蒙氏桨角蚜小蜂Eretmocerus mundus Mercet、 刺粉虱黑蜂Amitus hesperidum Silvertri不具有扩增效果, 对丽蚜小蜂的寄主包括不同生物型 (B型、 Q型、 ZHJ 1型和ZHJ 2型)的烟粉虱、 温室粉虱以及我国最常见的黑刺粉虱Aleurocanthus spiniferus (Quaintanca)等亦不具有扩增能力。同时, 该检测技术灵敏度高, 对成虫的最低检出阈值为7.812 ng/μL (相当于1/1 600头成虫)。研究结果对丽蚜小蜂的种类识别、 寄主谱的确定及其有效利用具有重要意义。     

Searching behaviour of Encarsia formosa as mediated by colour and honeydew

The habitat- and host-searching behaviour of female Encarsia formosa Gahan (Hymenoptera: Aphelinidae) was assessed using an airflow olfactometer and a filter paper test. Responses to different odour cues, colours, host-produced honeydew, non-host honeydew and single carbohydrates were determined. The parasitoid was not attracted to or arrested by odours emanating from clean tobacco leaves, tobacco leaves heavily infested with the host Trialeurodes vaporariorum (Westwood) (Homoptera: Aleyrodidae) and covered with honeydew, or honeydew alone. However, E. formosa females showed a significant response to green light transmitted through a tobacco leaf. The yellow part of the spectrum was partly responsible for this response. Thus, the long-range orientation is random with respect to the presence of hosts. Filter paper tests showed that the short-range searching behaviour is influenced by water soluble, non-volatile contact-kairomones contained in the host-produced honeydew. Contact with honeydew excreted by L3/L4 T. vaporariorum resulted in longer searching times than honeydew from adult T. vaporariorum or L3/L4 Bemisia tabaci Gennadius (Homoptera: Aleyrodidae). No difference was found between the response to honeydew excreted by adult and L3/L4 B. tabaci. The parasitoids' response to honeydew was unaffected by the host plant on which the whiteflies had fed. Non-host honeydew and single carbohydrates also affected the searching behaviour of E. formosa but to a lower extent than host honeydew. The possible differences in the carbohydrate and amino acid composition of the honeydew excreted by different life-stages of T. vaporariorum and B. tabaci are discussed.     

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。     

Variation between laboratory populations of Encarsia formosa in their parasitization behavior on the host Bemisia tabaci

We tested the hypothesis that two populations of the parasitoid Encarsia formosa Gahan (Hymenoptera: Aphelinidae) differed in their behavioral interactions with the whitefly host Bemisia tabaci Gennadius (Homoptera: Aleyrodidae). The two wasp populations were studied because previous work suggested large differences between the populations in performance on this host. In this study the populations differed behaviorally in both the number of hosts encountered and their reactions to hosts once encountered. The population reared for many years on Trialeurodes vaporariorum Westwood (Homoptera: Aleyrodidae) that previously performed more poorly on B. tabaci had a higher host encounter rate but rejected hosts more frequently. The population reared for a number of years on B. tabaci encountered fewer hosts but accepted a higher percentage of hosts for oviposition. The number of parasitized hosts did not differ between the two populations, however. These data demonstrate that there are heritable differences between these two populations of asexual wasps in host-associated behavioral traits. These behavioral differences in host acceptance do not explain performance differences seen in the earlier study, however, possibly due to different conditions between the two experiments.     

Delayed development of the whitefly (Bemisia tabaci) and increased parasitism by Encarsia bimaculata in response to sublethal doses of piperonyl butoxide

Abstract Effects of sublethal piperonyl butoxide (PB) on parasitization of Bemisia tabaci (Gennadius ) (Hemiptera: Aleyrodidae) by Encarsia bimaculata Heraty et Polaszek (Hymenoptera: Aphelinidae) were evaluated both in cage and greenhouse experiments. When first, second and third instar B. tabaci nymphs were treated with PB, all but the first instar were significantly prolonged. Data indicated that sublethal PB could improve E. bimaculata parasitism rates without influencing parasitoid eclosion rates. Prolonged development increased rates of parasitism by E. bimaculata, from 17.6% to 24.7% in cages, presumably by increasing the duration of host exposure. Sublethal PB combined with E. bimaculata as an integrated approach to control B. tabaci was evaluated using life table parameters under greenhouse conditions. Indices of population trend (I) calculated from life tables were estimated at 4.6 for B. tabaci exposed to PB and parasitoids compared to 14.1 with parasitoids alone and 23.5 in untreated controls. The results showed that after PB was sprayed and parasitoids introduced, development of B. tabaci was delayed and the peak of each stage was postponed. The older nymphal stage had highest mortality, primarily due to mortality caused by parasitism by E. bimaculata.     

寄主转换对B型烟粉虱生长发育和繁殖的影响

在实验室恒温条件下,对B型烟粉虱Bemisiatabaci(Gennadius)寄主转换后的生长发育和繁殖进行初步研究。结果表明:B型烟粉虱从番茄转移到国抗22棉花上后,第1代转寄主烟粉虱的发育历期比第2代长19.2%,存活率低16.4%,第2代和第3代之间没有明显差异。受体寄主对B型烟粉虱发育速率的恢复有一定的影响。     

双斑恩蚜小蜂寄生对烟粉虱体内保幼激素和20-羟基蜕皮酮含量的影响

用反相高效液相色谱法（RP-HPLC）测定了烟粉虱Bemisia tabaci体内保幼激素和20-羟基蜕皮酮的滴度。结果显示,被双斑恩蚜小蜂Encarsia bimaculata寄生的烟粉虱高龄若虫体内的保幼激素滴度显著高于（P<0.05）对照即未被寄生的高龄若虫,20-羟基蜕皮酮（20-E）滴度显著低于（P<0.05）对照,与未被寄生的低龄若虫滴度差异不显著,说明双斑恩蚜小蜂寄生后可以将烟粉虱高龄若虫的激素含量保持在低龄若虫的水平,从而调节烟粉虱高龄若虫的生长发育。烟粉虱伪蛹和成虫与对照体内保幼激素含量,烟粉虱伪蛹与对照之间20-E含量差异均不显著（P>0.05）。