不同虫态蠋蝽对黄栌胫跳甲幼虫的室内捕食反应

在天敌繁育室内研究蠋蝽Arma chinensis对黄栌胫跳甲Ophrida xanthospilota幼虫的捕食反应,功能反应试验数据用Holling方程分别进行模拟。结果表明:不同虫态蠋蝽的捕食量随黄栌胫跳甲幼虫密度的增加而增加,2～3龄蠋蝽若虫对跳甲1～3龄幼虫的捕食量高于对4～5龄幼虫的捕食量,4～5龄蠋蝽若虫和成虫对跳甲4～5龄幼虫的捕食量明显高于蠋蝽2～3龄若虫的捕食量。不同虫态蠋蝽捕食黄栌胫跳甲幼虫的圆盘方程能客观反映蠋蝽捕食量随黄栌胫跳甲密度变化而变化的情况;各虫态蠋蝽对跳甲1～2龄幼虫的控制作用差异不大,但蠋蝽4～5龄若虫和成虫对跳甲4～5龄幼虫的控制作用较2～3龄若虫更强。此结果可为野外释放蠋蝽防治跳甲提供依据,跳甲低龄幼虫期可释放2～3龄蠋蝽若虫,跳甲幼虫龄期较大时以释放4～5龄蠋蝽若虫或成虫为最佳。     

蠋蝽对3种主要松毛虫的捕食功能反应

马尾松毛虫、思茅松毛虫和云南松毛虫是湖南省3种主要松树害虫,蠋蝽是一种重要的捕食性昆虫。为探究蠋蝽对3种松毛虫的控害潜能,在实验室条件下,研究了不同龄期的蠋蝽3龄若虫、5龄若虫和成虫对松毛虫3龄幼虫的捕食能力。结果表明:每个虫态的蠋蝽对3种松毛虫3龄幼虫的捕食功能反应都符合HollingⅡ圆盘方程,在饱和猎物密度条件下,蠋蝽各虫态对马尾松毛虫3龄幼虫平均日最大捕食量依次为5.86头(成虫)5.10头(5龄若虫)2.79头(3龄若虫);蠋蝽各虫态对思茅松毛虫3龄幼虫平均日最大捕食量依次为4.10头(5龄若虫)4.02头(成虫)2.65头(3龄若虫);蠋蝽各虫态对云南松毛虫3龄幼虫平均日最大捕食量依次为4.27头(成虫)3.65头(5龄若虫)2.42头(3龄若虫)。其中,蠋蝽成虫对马尾松毛虫3龄幼虫控害潜能最大,a/T_h值为3.293 1。可见蠋蝽对3种松毛虫具有较大的捕食潜能,在松毛虫低龄幼虫期,选择蠋蝽成虫或5龄若虫释放防控效果最好。     

柞蚕蛹胶囊饲料及不同性比对饲养蠋蝽的影响

为有效降低用柞蚕Antheraea pernyi蛹人工饲养蠋蝽Aram chinensis的饲料成本,研究柞蚕蛹胶囊饲料制作;在室内分别用柞蚕蛹和其胶囊饲料饲养蠋蝽,观测其发育历期和繁殖力的变化,比较两种饲养方法的饲料成本;同时比较分析柞蚕蛹胶囊饲料饲养蠋蝽时,3种雌雄性比对蠋蝽繁殖力的影响。结果表明:用柞蚕蛹胶囊饲料饲养时,蠋蝽的成活率、若虫发育历期、成虫寿命、产卵量、卵孵化率与直接用柞蚕蛹饲养的均无显著差异,且饲料成本降低50%。用柞蚕蛹胶囊饲料饲养蠋蝽时,雌雄性比1∶1与3∶2配置间的产卵量及产卵次数差异不显著,但显著高于雌雄性比2∶3配置的,雌雄性比3∶2是人工饲养蠋蝽的最佳性比。     

蠋蝽对榆绿毛萤叶甲的室内捕食反应

榆绿毛萤叶甲Pyrrhalta aenescens是呼和浩特市危害园林植物较重的害虫之一,长期危害榆树Ulmus pumila。为有效控制其危害,提高呼和浩特市园林绿色防控技术水平,通过室内试验,研究蠋蝽对榆绿毛萤叶甲的捕食反应,功能反应数据用HollingⅡ方程进行模拟。结果表明:蠋蝽2～5龄若虫及成虫对榆绿毛萤叶甲3龄幼虫和成虫的捕食模型均符合HollingⅡ模型;随着猎物密度增加,蠋蝽的捕食量逐渐增加,搜寻效应降低;蠋蝽5龄若虫控害效果最好。     

蠋蝽对榆紫叶甲的捕食作用

榆紫叶甲Ambrostoma quadriimopressum Motschulsky是危害榆树Ulmus spp.的重要食叶害虫,通过室内外试验探讨蠋蝽Arma chinensis Fallou对榆紫叶甲的捕食能力。在室内,选择饥饿24 h的蠋蝽3,5龄若虫、成虫3个虫态,对10,20,30,40头共计4个密度的榆紫叶甲幼虫的捕食量测定,结果在不同的榆紫叶甲密度梯度下,蠋蝽的捕食量差异不显著;蠋蝽3,5龄若虫和成虫(各5头)对榆紫叶甲卵的捕食量分别为(9.54±3.39)粒、(50.69±25.96)粒和(50.98±21.37)粒,其中3龄若虫捕食量小于成虫和5龄若虫,差异显著。野外释放蠋蝽后榆紫叶甲得到了有效控制。     

利用人工饲料连代饲养蠋蝽若虫效果评价

蠋蝽Arma chinensis(Fallou)是在东亚地区广泛分布的捕食性天敌昆虫,在我国广泛运用于林木害虫的生物防治。为开展蠋蝽的人工繁育,利用人工饲料对蠋蝽连续饲养5代。结果表明:虽然雌性成虫的平均产卵前期时间和若虫发育所需时间略为延长,但人工饲料饲养的若虫雌雄个体间发育时间不存在显著差异,人工饲料能够满足蠋蝽生长和繁殖所需的营养,且性比和可育率与利用柞蚕蛹饲养的对照组无显著差异。通过评价人工饲料饲养的蠋蝽的生物学特性,为人工饲料的改良和优化提供理论依据。     

不同脂肪源人工饲料对蠋蝽生长发育及生殖力的影响

【目的】研究不同脂肪源人工饲料对蠋蝽生长发育及生殖力的影响,为天敌昆虫人工饲料开发提供依据。【方法】分别用含有棕榈酸油(饱和脂肪酸)的人工饲料1和亚麻酸油(不饱和脂肪酸)的人工饲料2连续饲养蠋蝽12代,并测定F1、F4、F8及F12蠋蝽各龄级若虫的发育历期和死亡率、性比(♀∶♂)、成虫体质量和产卵期、产卵量、卵孵化率及种群内禀增长率等生长发育和生殖力指标。【结果】2种人工饲料对蠋蝽生长发育及生殖力的影响效应与繁育世代数、生长发育阶段等相关。用2种饲料饲喂的蠋蝽2、3龄若虫的发育历期各代间均存在显著差异,而4、5龄蠋蝽若虫发育历期在饲养多代后(4龄至F8、5龄至F4)才开始表现出显著差异。随着饲养代数的增加,至F8时2种饲料对蠋蝽各龄期发育历期的影响效应才趋于稳定。一般地,饲料1对蠋蝽若虫早期发育更为有利即饲喂饲料1的蠋蝽2、3龄若虫发育历期显著低于饲喂饲料2的蠋蝽。而饲料2更适合蠋蝽若虫后期发育即饲喂饲料2的蠋蝽4、5龄若虫发育历期显著低于饲喂饲料1的蠋蝽。其他指标即卵、1龄若虫、总发育历期(仅F1存在显著差异)及成虫寿命,2种饲料间均无显著差异。与发育历期相似,F1蠋蝽2龄至5龄若虫死亡率及成虫获得率在2种处理间均无显著差异。随着饲养代数的增加,2种不同脂肪源饲料对蠋蝽各龄级死亡率及成虫获得率的影响开始增强即从F4开始均表现为饲料1处理的2龄和3龄若虫死亡率、成虫获得率都比饲料2处理的低,而4龄和5龄若虫死亡率都比饲料2处理的高。卵孵化率、1龄若虫死亡率,2种饲料间各代均无显著差异。饲养初期2种人工饲料处理的蠋蝽雌雄成虫体质量及雌成虫相对日均体质量增长率均无显著差异,随着饲养代数增加,至F8饲喂饲料1的蠋蝽雌雄成虫体质量、雌虫相对日均体质量增长率都显著低于饲料2。可育率在蠋蝽饲养开始时2种饲料间并未表现出差异显著性,但从F4开始饲料1饲养的蠋蝽可育率一直显著高于饲料2,而饲料1饲养的F1至F8蠋蝽种群内禀增长率以及种群倍增时间均优于饲料2。但这种差异随着饲养代数的增加,逐渐减少,至F12时的结果正好相反即饲料2饲养的蠋蝽种群内禀增长率以及种群倍增时间均优于饲料1。其他生殖力指标(成虫性比仅在F1存在显著差异)在2种人工饲料间均无显著差异。【结论】含有饱和脂肪酸的人工饲料(饲料1)可显著缩短蠋蝽低龄若虫发育历期、降低死亡率以及提高蠋蝽雌虫可育率,而含有不饱和脂肪酸的人工饲料(饲料2)更适合蠋蝽高龄若虫生长发育,提高成虫获得率和种群增长率。因此在以后的研究生产中可以通过在昆虫不同发育阶段添加或降低人工饲料中的某些关键营养物质,配制适合饲养对象特定生长阶段的人工饲料,从而使蠋蝽继代饲养达到最优效果。     

躅蝽密度对黄栌胫跳甲捕食的干扰效应研究

指出了在一定空间条件下,躅蝽2～5龄若虫和成虫对黄栌胫跳甲3龄幼虫的寻找效应随着龄期和自身密度的增加而不同,2龄躅蝽若虫对跳甲的平均捕食量4头/皿时最高,3～5龄躅蝽若虫均在2头/皿时最高,而成虫躅蝽对跳甲平均捕食量在1头/皿时为最高,此时各虫态对跳甲捕食的干扰效应最低,之后均随自身密度的增加而增加。各干扰模型中,经χ2检验,理论值和实测值拟合较好。     

美国白蛾新天敌—蠋敌捕食能力的初步观察

首次报道美国白蛾Hyphantria cunea(Drury)的一种捕食性天敌——蠋敌Arma chinensis(Fallou),简述了蠋敌的生物学特性。在商河县,蠋敌在美国白蛾幼虫网幕枝中的分布率为2.33%～17.86%;记述了蠋敌的捕食习性和规律,经室内饲养,统计出各龄若虫和成虫的捕食量,从若虫到成虫,最大捕食量为2头3龄、7头4龄、5头5龄、23头6龄共37头白蛾幼虫;最小取食量为4头2龄、8头3龄、1头4龄、1头5龄、2头6龄共16头白蛾幼虫;分析并指出蠋敌对美国白蛾具有较强的控制能力,是自然界中影响美国白蛾种群密度的重要因子。     

东亚小花蝽对红带滑胸针蓟马的捕食及防控能力

为明确东亚小花蝽Orius sauteri对园林害虫红带滑胸针蓟马Selenothrips rubrocinctus的室内捕食能力和野外防控能力，将东亚小花蝽成虫饥饿处理24 h后，与红带滑胸针蓟马2～3龄若虫按不同比例混合放置，24 h后统计捕食量；在野外按不同益害比释放东亚小花蝽成虫防治红带滑胸针蓟马，于释放后2,4,6 d统计捕食量。结果表明：东亚小花蝽成虫对红带滑胸针蓟马若虫的捕食功能反应均符合Holling-Ⅱ和Holling-Ⅲ模型，搜寻效应随猎物密度增大逐渐降低，捕食作用受自身密度的影响大于种内干扰；在野外不同益害比下，短期内各处理间的校正防效无显著差异。东亚小花蝽成虫在室内外对红带滑胸针蓟马均有较好的控制能力，可通过田间释放东亚小花蝽防治红带滑胸针蓟马。     

Characterization of larval instars of artemisia weevil, Adosomus sp.

The artemisia weevil, Adosomus sp., has become an important wormwood (Artemisia ordosoca and A. sphaerocephala) pest in recent years in Ningxia Province, China. The number of larval instars should be determined before further studies on its life history, biology and integrate management of pest (IMP). In this study, we measured the length and width of head capsule, based on frequency histograms and Dyar’s law, from which we concluded that the larvae of Adosomus sp. have four instars. Of the two variables measured, the width of head capsule provided the best division of instars. The average width of head capsule of the 1st instar larvae was 1.348±0.152 mm, the 2nd 2.109±0.199 mm, the 3rd 3.563±0.492 mm and the 4th 5.974±0.581 mm.     

无瓣海桑主要害虫绿黄枯叶蛾的取食行为研究

绿黄枯叶蛾Trabala vishnou Lefebure是红树林植物无瓣海桑Sonneratia apetala Buch-Ham的重要害虫,为制定科学的防治指标和防治策略,对该虫的取食行为和取食量进行了初步的研究。结果表明:绿黄枯叶蛾幼虫喜食无瓣海桑、尾巨桉,拒食秋茄、桐花树;幼虫5龄,1～3龄幼虫具有聚集性,4龄幼虫开始分散取食;1～2龄幼虫取食量少,3～5龄取食量占整个幼虫期取食量的98.12%,其中5龄幼虫的取食量占整个幼虫期取食量的74.52%;幼虫期平均取食无辨海桑叶片178.94 cm2/头,确定防治指标为9.8头/千叶。     

弧目大蚕蛾幼虫取食量研究

弧目大蚕蛾Neoris haraldi Schawerda幼虫5龄,平均龄期29.67 d。1龄幼虫取食量较少,平均日取食叶面积为4.25 mm2,2龄幼虫平均日取食叶面积为7.00 mm2,3龄幼虫取食量猛增,平均日取食叶面积为83.06 mm2,4龄幼虫平均日取食叶面积为231.90 mm2,5龄幼虫平均日取食叶面积为278.86 mm2。2龄以前幼虫食量较小,仅占全部食量的1.19%;3龄后幼虫食量占全部食量的98.81%。5龄幼虫日均食量较多,取食天数也达到8 d,占总取食量的52.35%,危害也较2龄以前的幼虫严重。弧目大蚕蛾幼虫头宽、体长、体重、取食量与龄期相关极显著。     

松褐天牛肿腿蜂对松褐天牛低龄幼虫控制作用的研究

研究测定了松褐天牛肿腿蜂对松褐天牛1～3龄幼虫的控制作用,采用林间和室内罩网相结合的方法研究了2组松褐天牛肿腿蜂对松褐天牛幼虫的寄生情况.结果显示:在室内试验条件下,松褐天牛肿腿蜂产卵之前的刺蛰、补充营养取食能直接造成松褐天牛1～3龄幼虫死亡,对1、2及3龄幼虫的平均致死率分别为95.66％、85.91％、57.88％,并可产卵寄生2、3龄幼虫;林间释放2组松褐天牛肿腿蜂后,在刺蛰和补充营养取食后能有效寄生寄主的肿腿蜂雌蜂数量比例变化较大,有效肿腿蜂率最高为14.9％,最低为2.3％.松褐天牛肿腿蜂寄生行为不受寄主聚集程度的影响,但刚羽化出茧肿腿蜂雌蜂的寄生效率比经饲喂后的雌蜂高近5倍.从肿腿蜂单一个体来看,每头雌蜂补充营养取食和产卵寄生致死的松褐天牛幼虫数为2.1～7.7头.松褐天牛肿腿蜂雌蜂的补充营养习性及刺蛰、取食致死寄主行为在防治中有很重要的作用,表明该种肿腿蜂是防治松褐天牛的重要天敌,在生物防治松褐天牛幼龄幼虫上具有良好的应用前景.     

白蜡窄吉丁幼虫的龄数和龄期测定

采用林间定期调查取样的方法，测定白蜡窄吉丁幼虫的龄数以及各龄的龄期；分别测量不同发育阶段幼虫的体长、体宽(第7腹节最宽处)、前胸背板宽、口缘宽、尾又长和尾叉前缘宽等6项指标，以期找出区分和判定幼虫虫龄的最佳形态特征及指标。结果表明：白蜡窄吉丁幼虫有4龄，尾又及其长度可作为理想的分龄特征和分龄指标；幼虫的口缘宽度也可作为指标之一；体长、体宽、前胸背板宽和尾又前缘宽变异较大，不宜用于分龄。研究还发现：幼虫尾叉内侧的形态特征是区分幼虫虫龄的简洁而方便的方法。利用种群众数龄期法测定各龄的平均龄期分别为：1龄18．1d，2龄11．2d，3龄10．7d，4龄261．2d，幼虫期共为301．3d。     

Functional responses of the parasitoid,Ertmocerus longipes Compere (Hym., Aphelinidae) to densities of the whitefly,Aleurotuberculatus takahashi David et Subramaniam (Hom., Aleyrodidae) at different temperatures

The present study dealt with the functional responses of the parasitoid,Eretmocerus longipes Compere (Hym., Aphelinidae) to the densities of the whitefly,Aleurotuberculatus takahashi David et Subramaniam (Hom., Aleurodidae) at different temperatures under the laboratory conditions. The results showed that when the initial densities ofA. takahashi-3rd instar were raised from 10 to 320 ind./leaf, the numbers of parasitized nymphs increased as well, ranging from 7.0 to 23.1 at 20°C, 9.8 to 42.9 at 25°C, 6.7 to 39.9 at 30°C, and 1.8 to 8.3 ind./leaf at 35°C, respectively. The Holling Disk Equation was introduced to build up the models of functional responses. The response curves remained type II, although the numbers of parasitized nymphs were significantly different under different temperatures. The suitable initial densities of the host whitefly for parasitization were about 80 individuals per leaf. A negative relation was observed between the initial densities of the whitefly and the parasitization rates by the parasitoid. An increase in the initial densities ofA. takahashi-3rd instars ranging from 10 to 320 ind./leaf resulted in a decrease in the parasitization rate byE. longipes ranging from 70.0% to 7.2% at 20°C, 98.0% to 13.4% at 25°C, 67.0% to 12.5% at 30°C and 18.0% to 2.6% at 35°C with a value of 0.2877 was significantly smaller than that at 20°C with a vlaue of 1.3354, that at 25°C with a value of 1.6465 and that at 30°C with a value of 1.1199, respectively (p<0.01). The handling time (Th) forE. longipes was 0.1521 at 35°C, significantly longer than 0.0510 at 20°C, 0.0289 at 25°C and 0.0320 at 30°C, respectively (p<0.01). The maximum loading number (K) of the parasitized nymphs with a value of 34.5 ind./leaf at 25°C was similar to that with a value of 31.2 ind./leaf at 30°C, about 1.8 times as high as that with a value of 19.6 ind./leaf at 20°C and 4 times more than that with a value of 6.6 ind./leaf at 35°C. It was suggested that temperature affected the functional response by balancing searching rate and handling time. The optimal temperature range for the functional responses ofE. longipes to the densities ofA. takahashi-3rd instar was 25° to 30°C.     

Assessment of the biological control capability of <Emphasis Type="Italic">Hippodamia variegata</Emphasis> (Col.: Coccinellidae) using functional response experiments

Lady beetles are among the most successful predators of aphids in different environments. The functional responses of different life stages of Hippodamia variegata (Goeze) towards cotton aphids were examined in two different set-ups, a two-dimensional Petri dish set-up with detached leaves and a three-dimensional set-up with whole plants. In addition, the functional responses in two-dimensional set-ups towards cotton aphids and the pea aphids were compared. H. variegata exhibited a functional type II response to both cotton aphids and pea aphids irrespective of life stage and spatial scale of the set-up. Females and fourth instars generally had higher search rates than third instars whereas handling times were consistently lower for the fourth instar stage compared with the preceding juvenile stage and with females. The spatial dimensions did not have any significant influence on the functional responses towards cotton aphids, except for third instars which in the three-dimensional set-up reduced their search rate and increased their handling time. Fourth instars reacted in the same way to both Aphis gossypii and Acyrthosiphon pisum whereas the functional response parameters for third instars and females were significantly different on the two prey species. Our study, a part of this first-step evaluation of H. variegata as a biocontrol agent against A. gossypii and A. pisum under field condition, suggest that the voracity of all tested stages of H. variegata towards both aphid species hold good promises for a use of especially fourth instars and females in inundative biocontrol.     

豫西地区中华松针蚧生物生态学特性初步研究

中华松针蚧Sonsaucoccus sinensis Chen雌雄异型，1a发生1代，雌虫2龄，终生被蜡质蚧壳，不爬出壳外。雄虫3龄，3龄若虫爬出壳外化蛹，进而羽化成虫。滞育期在6月下旬至8月中旬，滞育期解除后1龄寄生若虫蜕变为2龄无肢若虫，继续危害至10月份，并以2龄无肢若虫越冬。各虫态出现期因海拔和气温变化而有差异。海拔高、气温低发育迟，反之发育早。该虫主要是通过风、雨和人为活动等途径传播。化学防治的有利时机在初孵若虫期。     

Studies on morphology and biology of immature stages of the predator Rhyzobius lophanthae Blaisdell (Col.: Coccinellidae)

Morphological characteristics of immature developmental stages of Rhyzobius lophanthae Blaisdell (Col.: Coccinellidae), predator of scale insects of the family Diaspididae (Homoptera), are described. Data about the morphology of eggs, the four larval instars, and the pupa is presented. Larval instars are described in more detail: size of head capsule, length of tibia, distribution of dorsal and lateral setae of abdomen segments for each larval instar is reported. Distribution of spiracles is also given. Study on the biology concerns the influence of prey on the duration of instar periods. The diaspidids Aspidiotus nerii and Aonidiella aurantii were used as food. The mean duration of the developmental period from egg to adult was 27.1 days, and no mortality was observed (0?%) when A. nerii was used as prey. The respective numbers when the prey was A. aurantii were 48.8 days and 84?%.