东亚小花蝽成虫对西花蓟马若虫的捕食功能反应与搜寻效应

为探明东亚小花蝽对西花蓟马的控制效能,开展了东亚小花蝽成虫对西花蓟马若虫的捕食功能反应与搜寻效应研究。结果表明,在供试温度下,该捕食功能反应符合HollingⅡ型方程。在相同温度下,东亚小花蝽成虫的捕食量随着猎物密度的增加而增大,搜寻效应随着猎物密度的增加而降低。在18℃～26℃内,随着温度的升高,东亚小花蝽成虫对西花蓟马若虫的捕食量增加,而在26℃～34℃则有相反的趋势。在相同猎物密度条件下,随着东亚小花蝽成虫密度的增大,其平均捕食量逐渐减少,捕食作用率也相应地降低,东亚小花蝽成虫之间存在分摊竞争。     

东亚小花蝽(Orius sauteri)成虫对入侵害虫西花蓟马(Frankliniella occidentalis)成虫的捕食作用

为探明东亚小花蝽对西花蓟马的控制效能,开展了东亚小花蝽成虫对西花蓟马成虫的捕食功能反应与寻找效应研究。试验结果表明,在供试温度下,其捕食功能反应符合HollingⅡ型方程。在相同温度下,东亚小花蝽成虫的捕食量随着猎物密度的增加而增大,搜寻效应随着猎物密度的增加而降低。在18～26℃,随着温度的升高,东亚小花蝽成虫对西花蓟马成虫的捕食量增加,而在26～34℃则有相反的趋势。在相同猎物密度条件下,随着东亚小花蝽成虫密度的增大,其平均捕食量逐渐减少,捕食作用率E也相应地降低,捕食作用率E与东亚小花蝽成虫密度P的关系为E=0．5224P^-0.7148,分摊竞争强度,与东亚小花蝽成虫密度P的关系为I=0．9689logP＋0．0763。     

南方小花蝽对西花蓟马和蚕豆蚜的捕食作用

南方小花蝽Orius similis是多种小型害虫的重要天敌昆虫,为了掌握其控制潜能,本文研究了南方小花蝽对西花蓟马Frankliniella occidentalis和蚕豆蚜Aphis craccivora的捕食作用。研究结果表明南方小花蝽3～5龄若虫和雌成虫对西花蓟马和蚕豆蚜的功能反应均符合HollingⅡ型方程,南方小花蝽3～5龄若虫和雌成虫对西花蓟马2龄若虫的瞬时攻击率均高于蚕豆蚜。南方小花蝽5龄若虫对蚕豆蚜的控制能力比雌成虫强,而对西花蓟马的控制能力比雌成虫差。南方小花蝽5龄若虫对西花蓟马2龄若虫和蚕豆蚜的捕食率（E）随着捕食者自身的密度（P）的增加而下降,其干扰反应方程分别为E=0.412P-1.623和E=0.416P-1.639。南方小花蝽5龄若虫对西花蓟马2龄若虫和蚕豆蚜有明显的选择性,5龄若虫喜欢取食西花蓟马2龄若虫,但前期取食的猎物对其选择性有明显的影响,更喜欢选择前期取食过的猎物。     

不同光谱对东亚小花蝽捕食西花蓟马的影响

设施补光可能会影响天敌昆虫的应用效率,为探索提升天敌应用效果的补光光谱,促进补光与天敌释放技术的有机结合,本研究在相同光强和光周期的条件下,比较了红（R）、蓝（B）、红蓝组合（RB）和白（W,对照）光处理下东亚小花蝽对西花蓟马捕食能力的差异。结果表明,相比于W光,B光显著降低东亚小花蝽雌成虫的存活率,R和RB光未影响其雌成虫的存活。R和RB光显著增加东亚小花蝽在高密度猎物下对西花蓟马的捕食量。不同光谱处理下东亚小花蝽雌成虫对西花蓟马雌成虫的捕食能力均符合Holling II型功能反应模型,且搜寻效应随猎物密度增加逐渐降低。RB光处理下,东亚小花蝽捕食西花蓟马的效果最好,理论日最大捕食量最高,为43.10头/ d,单头猎物处理时间最短,为0.0232 d;B光的理论日最大捕食量也较高,为42.90头/ d,单头猎物处理时间为0.0233 d;R光下东亚小花蝽捕食西花蓟马的瞬时攻击率最高为1.0837。东亚小花蝽对西花蓟马的搜寻效率最高的是RB光处理,其次是R或B光,最低的是W光。以上结果表明,相比于W光,R、B和RB光均增加东亚小花蝽对西花蓟马的捕食能力和搜寻效率,但B光会降低东亚小花蝽的存活率。因此,与设施补充R和RB光相结合,可潜在提升东亚小花蝽对西花蓟马的捕食效果。本文基于捕食功能差异评价了三种常用补光光谱对东亚小花蝽捕食西花蓟马的影响,为设施补光兼顾天敌应用提供了基础数据。     

东亚小花蝽对西花蓟马的控害能力评价

在实验室条件下,采用编制特定年龄生命表的方法,获得东亚小花蝽Orius sauteri和西花蓟马Frankliniella occidentalis的重要种群生物学参数,进而分析评价东亚小花蝽对西花蓟马的控害能力。结果表明：东亚小花蝽的净生殖力（22.6）和内禀增长率（0.1345）均大于西花蓟马（20.2、0.1225）。此外,东亚小花蝽的世代历期（23.17 d）和种群倍增时间（5.15 d）均小于西花蓟马（24.54 d、5.65 d）。另外,东亚小花蝽的单雌平均产卵量（61.8粒）大于西花蓟马（35.4粒）。综合上述研究结果说明,东亚小花蝽的种群扩繁速度大于西花蓟马,且具有控制西花蓟马种群增长的巨大潜力。     

微小花蝽的发生及其对西花蓟马的捕食作用

本文研究了不同种植模式下月季上微小花蝽种群的发生特点及其对西花蓟马的捕食作用,结果表明:在昆明月季种植区,微小花蝽每年有2个发生高峰期,分别是4～5月份和8～9月份,其中,以4～5月份种群发生量最高;露地月季田块上的微小花蝽种群密度明显高于温室大棚;微小花蝽在不同月季品种上的种群密度也有所差异,月季艳粉品种上的蓟马种群...     

南方小花蝽在不同试验空间对西花蓟马的捕食及搜寻效应

【背景】南方小花蝽是一类很有利用前景的捕食性天敌,而有关其在不同捕食空间下对我国局部地区暴发成灾的重要入侵害虫西花蓟马捕食控制效能的研究较少。【方法】在实验室条件下比较研究了南方小花蝽成虫在不同试验空间对西花蓟马成虫、若虫的捕食选择性、捕食功能反应与搜寻效应。【结果】南方小花蝽成虫对西花蓟马若虫的捕食选择性强于成虫;在相同的试验空间,南方小花蝽成虫的日均捕食量随猎物数量的增加而增大,其对西花蓟马成虫和若虫的捕食量在猎物数量为每指形管中60头时最大,分别为15.90和19.30头;而搜寻效应随猎物数量的增加而降低。在各供试条件下,捕食功能反应均符合Holling Ⅱ型方程;南方小花蝽成虫在小饲养容器中对西花蓟马若虫的瞬时攻击率最大,为1.2794;而在大饲养容器中对西花蓟马成虫的瞬时攻击率最小,仅为0.3506,其处理1头西花蓟马成虫的时间约需0.0402d,而处理1头若虫的时间仅需0.0242d。在相同的猎物数量下,南方小花蝽成虫在大饲养容器中对西花蓟马的日均捕食量均低于其在小饲养容器中对西花蓟马的日均捕食量。【结论与意义】南方小花蝽对西花蓟马有很强的捕食效能,对西花蓟马的种群消长具有一定控制作用。本研究旨在为应用南方小花蝽防治西花蓟马积累资料,同时为西花蓟马的综合治理奠定理论基础。     

南方小花蝽在不同试验空间对西花蓟马的捕食及搜寻效应

【背景】南方小花蝽是一类很有利用前景的捕食性天敌,而有关其在不同捕食空间下对我国局部地区暴发成灾的重要入侵害虫西花蓟马捕食控制效能的研究较少。【方法】在实验室条件下比较研究了南方小花蝽成虫在不同试验空间对西花蓟马成虫、若虫的捕食选择性、捕食功能反应与搜寻效应。【结果】南方小花蝽成虫对西花蓟马若虫的捕食选择性强于成虫;在相同的试验空间,南方小花蝽成虫的日均捕食量随猎物数量的增加而增大,其对西花蓟马成虫和若虫的捕食量在猎物数量为每指形管中60头时最大,分别为15.[KG-*8]90和19.[KG-*8]30头;而搜寻效应随猎物数量的增加而降低。在各供试条件下,捕食功能反应均符合Holling Ⅱ型方程;南方小花蝽成虫在小饲养容器中对西花蓟马若虫的瞬时攻击率最大,为1.[KG-*8]2794;而在大饲养容器中对西花蓟马成虫的瞬时攻击率最小,仅为0.[KG-*8]3506,其处理1头西花蓟马成虫的时间约需0.[KG-*8]0402 d,而处理1头若虫的时间仅需0.[KG-*8]0242 d。在相同的猎物数量下,南方小花蝽成虫在大饲养容器中对西花蓟马的日均捕食量均低于其在小饲养容器中对西花蓟马的日均捕食量。【结论与意义】南方小花蝽对西花蓟马有很强的捕食效能,对西花蓟马的种群消长具有一定控制作用。本研究旨在为应用南方小花蝽防治西花蓟马积累资料,同时为西花蓟马的综合治理奠定理论基础。     

东亚小花蝽对西方花蓟马和二斑叶螨的捕食选择性

多食性天敌对猎物的捕食选择性及猎物密度对天敌捕食的干扰作用直接影响到天敌对不同猎物的控制作用.在实验室条件下研究了东亚小花蝽对西方花蓟马和/或二斑叶螨不同虫态的捕食选择性,以及两猎物中一种猎物的密度变化对小花蝽取食另一种猎物的影响.结果如下:东亚小花蝽5龄若虫和成虫对西方花蓟马2龄若虫的捕食选择性均强于对其成虫,对二斑叶螨的选择性为雌成螨>若螨>幼螨.实验中西方花蓟马2龄若虫是东亚小花蝽最喜好的虫态.二斑叶螨雌成螨密度固定为60头/19.63cm2,西方花蓟马若虫密度从10增加到60时显著地减少了东亚小花蝽对二斑叶螨的取食.反之,固定西方花蓟马同样密度,增加二斑叶螨密度却没有显著改变小花蝽对西方花蓟马的取食.此结果进一步表明,西方花蓟马是东亚小花蝽更喜好的猎物.     

东亚小花蝽对西花蓟马和/或二斑叶螨危害豆株的定位反应

多食性天敌对其猎物植物系统的选择是其重要生物学特性之一,决定了对不同猎物控制的有效性。东亚小花蝽Orius sauteri是西花蓟马Frankliniella occidentalis(Pergande)及二斑叶螨Tetranychus urticae的重要捕食性天敌。本文在温室笼罩条件下通过释放东亚小花蝽,而后在不同时间调查其在西花蓟马和/或二斑叶螨危害2d后的豆株及健株上的数量,研究了其定位反应。结果表明:东亚小花蝽显著趋向西花蓟马及由西花蓟马与二斑叶螨同时危害的豆株,而较少趋向二斑叶螨单独危害的豆株及健株。在各处理豆株上,东亚小花蝽的日活动规律中,傍晚时分有离开植株的趋势。     

Olfactory response towards its prey Frankliniella occidentalis of wild and laboratory‐reared Orius insidiosus and Orius laevigatus

Orius species are important biological control agents of thrips in protected crops. Rearing conditions in mass production facilities may affect their performance in the crop when searching for the target prey. The aim of this study was to evaluate and compare the search behaviour and orientation towards prey of two Orius species, O. laevigatus (Fieber) and O. insidiosus (Say) that have been reared in the laboratory under different conditions, with wild (field‐collected) individuals. Adult predator females were placed in a Y‐tube olfactometer and offered a choice between the odours released by plants of different species (cotton, common bean, sweet pepper and cucumber), which were either non‐infested or infested with Frankliniella occidentalis (Pergande) adults.O. laevigatus and O. insidiosus responded to odours from thrips‐infested plants and these responses were influenced by the origin of the colonies. A larger percentage of laboratory‐reared O. laevigatus females (42%) did not made a choice between thrips‐infested or clean plants, compared with wild individuals (17%). Of those females that did respond to plant odours, a smaller percentage of laboratory‐reared O. laevigatus females (34%) responded to the odours from thrips‐infested plants compared with wild insects (76%). No significant differences were found inO. insidiosus females that did not make a choice between thrips‐infested or clean plants (14% for wild vs. 17% for lab individuals). Also, no significant differences were found between O. insidiosus females that selected thrips‐infested plants at the corresponding proportion of wild (75%) and laboratory‐reared (70%) individuals. We propose that the olfactometer test could be a complementary evaluation aspect to the already developed quality criteria for performance of mass‐reared Orius predators.     

Ovipositing Orius laevigatus increase tomato resistance against Frankliniella occidentalis feeding by inducing the wound response

The anthocorid predator Orius laevigatus is widely used as biological control agent of thrips pests, including the western flower thrips Frankliniella occidentalis. In the current study, it was shown that O. laevigatus adults can increase plant resistance to feeding damage of F. occidentalis on tomato plants. The predator elicits a jasmonic acid (JA) mediated wound response during endophytic oviposition, resulting in reduced thrips feeding. A strong accumulation of H₂O₂, a molecule involved in different parts of the wound response, in leaf tissue surrounding the predator eggs or oviposition puncture sites was observed. Infestation of tomato plants with adult predators led to the upregulation of three JA regulated wound responsive genes: the precursor prosystemin, the jasmonic acid biosynthesis enzyme allene oxide synthase and the defence protein proteinase inhibitor I. Likewise, the presence of adults caused accumulation of proteinase inhibitor II, a principal marker for the wound response.     

Potential use of the fungus Beauveria bassiana against the western flower thrips Frankliniella occidentalis without reducing the effectiveness of its natural predator Orius sauteri (Hemiptera: Anthocoridae)

Orius sauteri (Poppius; Hemiptera: Anthocoridae) is an important predator of western flower thrips, Frankliniella occidentalis (Pergande; Thysanoptera: Thripidae). O. sauteri would be directly exposed to the entomopathogenic fungus Beauveria bassiana (Bals.) Vuillemin in the field should the fungus be used as a biopesticide. If the fungus were to negatively affect O. sauteri in agro-ecosystems, predation of F. occidentalis by O. sauteri may be limited. The present study was undertaken to evaluate the insecticidal activity of strain B.bassiana-RSB of B. bassiana, which is highly virulent to F. occidentalis, on the predator under laboratory conditions. Results showed that, regardless of the concentration applied to first instars, Bb-RSB was not insecticidal against O. sauteri, nor did direct applications affect the developmental rate of the predator. Significant differences in developmental rates and adult longevity were observed between O. sauteri that fed on Bb-RSB-infected F. occidentalis cadavers and those that fed on untreated thrips. Developmental time (from first instar to adult) increased from 0.3 to 0.7 days and adult longevity decreased by 0.8 to 1.2 days for predators fed thrips treated with low and high concentrations of strain Bb-RSB, respectively, compared with predators fed on untreated thrips. However, these differences were only 3–13% of mean values for the controls, suggesting that the effects of Bb-RSB on O. sauteri are relatively minor. These findings highlight the potential use of O. sauteri in combination with B. bassiana for the biocontrol of F. occidentalis, but field tests must be performed to confirm their compatible use.     

Population dynamics of Frankliniella occidentalis Pergrande and its predator Orius similis Zheng on common crops and surrounding plants

Frankliniella occidentalis Pergrande is important invasive pests in China, causing damage to agricultural production, and Orius similis Zheng is the dominant predator species of F. occidentalis. A two-year survey was conducted to determine the population density of F. occidentalis and O. similis, on chili (Capsicum annuum L.) and maize (Zea mays L.) crops and surrounding weed species, which included white clover (Trifolium repens L.), St. John's wort (Hypericum beanii N. Robson), alfalfa (Medicago sativa L.) and beggarticks (Bidens pilosa L.) in Kunming, southern China. The activity of F. occidentalis on these 6 host plant species was determined using the quartile method. F. occidentalis mainly damaged plants during their flowering stage. The main activity period of F. occidentalis occurred earlier on H. beanii and T. repens than on C. annuum. The peak activity of F. occidentalis occurred in the middle of May (on T. repens). During the whole activity period, the highest thrips densities were recorded on H. beanii among all of the sampled host plant species, followed by C. annuum. The lowest density was recorded on B. pilosa. Dynamics of immature F. occidentalis were more irregular than that of adults. The highest density of O. similis was recorded on Z. mays. It was 2.27–26.43-fold (2017) and 2.01–19.09-fold (2018) higher than that on other host plant species. This study showed that F. occidentalis could migrate between C. annuum and surrounding weeds. The weeds were the main source of thrips on C. annuum. The results indicated that Z. mays can be planted around C. annuum fields as a potential banker plant, to attract O. similis to control F. occidentalis on C. annuum, T. repens and B. pilosa. The flowering period of plants and surrounding plant species has a great effect to the population activities of F. occidentalis and predator O. similis on crops.     

外源茉莉酸诱导菜豆对西花蓟马和南方小花蝽的行为反应

【目的】为明确茉莉酸诱导的菜豆对西花蓟马Frankliniella occidentalis和南方小花蝽Orius similis的行为反应。【方法】采用四臂嗅觉仪测定了西花蓟马和南方小花蝽对不同浓度茉莉酸诱导菜豆后的行为反应,并用气相色谱-质谱联用仪测定了不同浓度茉莉酸处理后菜豆挥发物的成分。【结果】不同浓度茉莉酸处理的菜豆植株对西花蓟马和南方小花蝽分别有不同程度的驱避和吸引作用,以1 mmol/L的茉莉酸处理植株对西花蓟马的驱避作用最强,0.1 mmol/L的茉莉酸处理植株对南方小花蝽的吸引作用最强。不同处理菜豆的挥发物在含量和成分上存在显著差异,(Z)-3-己烯丙酸酯、2-异丙基-甲氧基毗嗦只有在茉莉酸处理植株中检测到。结合不同浓度茉莉酸处理植株对西花蓟马和南方小花蝽的行为反应及菜豆挥发物含量的变化趋势,推测(E)-2-己烯醛对西花蓟马有驱避作用,(E)-2-乙酸叶醇酯对南方小花蝽具有引诱作用。【结论】茉莉酸处理菜豆后,植物挥发物种类和含量发生了变化,在增强菜豆植株抗虫性的同时,还可增强捕食性天敌南方小花蝽的搜索和捕食能力。     

小花蝽对牛角花齿蓟马的捕食作用

在室内研究了小花蝽(Orius minutus)成虫对牛角花齿蓟马(Odontothrips loti)3～4龄若虫的捕食作用和种内干扰作用.结果表明,小花蝽对牛角花齿蓟马的捕食功能反应均符合HollingⅡ型方程,在玻璃试管中,捕食量(N_a)符合Na＝1.0113N／(1＋0.04149N),在培养皿中为N_a＝0.6777N／(1＋0.03395N),在笼罩花盆中为N_a＝0.6417 N／(1＋0.03934 N).小花蝽的捕食作用有较强的种内干扰反应,捕食率与个体相互干扰的关系符合Hassell模型.在相同空间条件下,小花蝽的捕食量与猎物密度呈正相关,寻找效应与猎物密度呈负相关;随着空间增大,小花蝽对牛角花齿蓟马若虫的瞬间攻击率(a′)和最大捕食量(N_a)均下降,处置时间(T_h)则延长,但其功能反应类型不变,仍为HollingⅡ型.