温度对副珠蜡蚧阔柄跳小蜂发育和繁殖的影响

通过观察副珠蜡蚧阔柄跳小蜂Metaphycus parasaissetiae Zhang and Huang在18,21,24,27,30,33和36℃恒温条件下的生长发育情况,求得其世代发育起点温度和世代有效积温分别为13.10℃和215.00日.度,建立世代发育历期预测式为N=[215.00±44.32]/[T-(13.10±3.24)],世代发育速率与温度之间的关系拟合为S形曲线V=-e(1.33+37.73/T),推算出该蜂在海南1年可发生18代。所设试验温度范围内,该蜂对橡副珠蜡蚧Parasaissetia nigra(Nietner)的寄生率在13.33%～20.00%范围内波动,30℃时寄生率最高;雌性比率在27℃时最大为70.03%。随着试验温度的升高,成蜂羽化相对集中,羽化持续时间逐渐缩短,羽化高峰提前。30℃条件下雌蜂终生产卵量最多,平均25.77粒。雌蜂寿命随试验温度的升高而逐渐缩短,同一恒温条件下补充20%蜂蜜水可显著延长雌蜂寿命。27～30℃可视为有利于副珠蜡蚧阔柄跳小蜂发育繁殖的适温范围,最适温度为30℃。     

副珠蜡蚧阔柄跳小蜂的寄生影响因子

副珠蜡蚧阔柄跳小蜂Metaphycus parasaissetiae是橡副珠蜡蚧Parasaissetia nigra成虫的重要内寄生蜂。寄生蜂的寄生效果受多种因素影响,就温度、光周期、寄主成虫日龄、雌蜂日龄及交配等因子对副珠蜡蚧阔柄跳小蜂的寄生率、每头寄主的出蜂量及后代雌性率的影响进行研究,以期探明几种因子对该蜂寄生效果的影响。结果表明:温度为27—30℃时寄生率最高为91.7%,出蜂量以27℃最高为7.5头,雌性率以24℃条件最高为72.1%,其次27℃为62.6%,说明24—30℃是寄生效果较好的适温范围;光周期对副珠蜡蚧阔柄跳小蜂的影响明显,光暗比为12 h∶12 h条件下,其寄生率、出蜂量、后代雌性率均最大,分别为70.6%、5.3头、68.3%;副珠蜡蚧阔柄跳小蜂寄生用20—21日龄橡副珠蜡蚧成虫的寄生率、出蜂量及后代雌性率均为最高,分别为87.0%、5.6头、51.2%,说明20—21日龄的橡副珠蜡蚧成虫是副珠蜡蚧阔柄跳小蜂最适合寄生的阶段;雌蜂日龄对寄生效果的影响明显,3日龄的出蜂量最多为5.6头,4日龄的小蜂寄生率最高为81.7%,5日龄的雌性率最大为55.2%;交配是另一影响寄生效果及性比的重要因子,已交配的寄生率及出蜂量显著高于未交配的,分别为91.7%、7.5头,交配的雌性率为62.1%,而未交配所育后代均为雄蜂。综合以上结果分析,可考虑选用20—21日龄橡副珠蜡蚧成虫、充分交配的3—6日龄小蜂、温度27℃及光周期L∶D=12∶12作为室内扩繁副珠蜡蚧阔柄跳小蜂的理想条件组合。     

低温对副珠蜡蚧阔柄跳小蜂发育及繁殖的影响

副珠蜡蚧阔柄跳小蜂是橡副珠蜡蚧的重要寄生蜂。为了探明副珠蜡蚧阔柄跳小蜂对低温的适应性,本文在15℃-24℃范围内对该蜂的产卵、发育、出蜂量及性比进行观察。结果表明:副珠蜡蚧阔本跳小蜂在15℃-24℃范围内,随温度的升高,产卵量逐渐增加;该蜂在21℃、24℃时蜂能完成世代发育,在15℃、18℃时少量跳小蜂能发育到蛹,但均不能羽化为成蜂;温度对性比的影响明显,24℃的雌性比例高于21℃。综上所述,副珠蜡蚧阔柄跳小蜂对18℃以下的低温适应性较差,室内繁殖或野外放蜂时注意选择较高的温度条件。     

蓝色长盾金小蜂对橡副珠蜡蚧的控制作用

蓝色长盾金小蜂Scutellista caerulea Fonscolombe是橡胶树重要害虫橡副珠蜡蚧Parasaissetia nigra Nietner的一种外寄生性天敌。为了明确蓝色长盾金小蜂对橡副珠蜡蚧的控害潜能,为该寄生蜂的进一步利用提供数据支撑。在室内通过体视镜下解剖观察寄生蜂在寄主腹下是否产卵测定了不同温度、寄主发育阶段下蓝色长盾金小蜂的寄生功能反应、寻找效应和自身密度干扰效应。温度设置有21、24、27、30、33、36℃共6个处理,寄主发育阶段设初期成虫（1-2 d成虫）、褐色期成虫（体色褐色,产卵前3-4 d成虫）、黑色期成虫（体色黑色,产卵1-2 d成虫）三个处理。结果显示：蓝色长盾金小蜂对橡副珠蜡蚧的寄生功能反应符合Holling-Ⅱ型和Holling-Ⅲ型模型,在21-36℃范围内,33℃时该蜂寄生效能最大,为44.4201,21℃时最小,为9.2458;在橡副珠蜡蚧为初期成虫-黑色期成虫范围内,寄生效能由大到小为黑色期成虫>褐色期成虫>初期成虫,分别为18.9044、13.7410、7.2002。采用Hassell-Varley干扰模型对不同温度下蓝色长盾金小蜂受自身密度干扰的寄生作用率进行拟合,表明蓝色长盾金小蜂在寄生时存在种群内个体间自我干扰情况。温度会影响蓝色长盾金小蜂的搜寻和自我干扰,在21-33℃范围内,33℃搜寻常数和干扰常数达到最大值,分别为0.6116、0.7535。当温度为33℃,寄主发育阶段为黑色期成虫时,蓝色长盾金小蜂对橡副珠蜡蚧有较强的控制能力,自身干扰作用最强。     

葡萄绵蜡蚧的重要寄生蜂——多孔阔柄跳小蜂(膜翅目:跳小蜂科)

记述了西藏昌都地区葡萄绵蜡蚧Pulvinaria vitis （Linnaeus）的重要寄生蜂多孔阔柄跳小蜂Metaphycus annasor Guerrieri ＆ Noyes,该种为中国新记录种。研究标本保存在中国科学院动物研究所。     

白蜡虫阔柄跳小蜂实验种群生命表的研究

观察了温度对白蜡虫阔柄跳小蜂（Metaphycus ericeri Xu et Jiang）存活和繁殖的影响,组建了18℃、21℃、24℃、27℃、30℃和33℃6种温度下的实验种群生命表,白蜡虫阔柄跳小蜂的世代存活率为24℃＞27℃＞30℃＞21℃＞33℃＞18℃＞15℃,温度过高或过低对白蜡虫阔柄跳小蜂的存活和繁殖不利,24℃和27℃雄虫的怀卵量、产卵量和产卵百分率都显著高于其它温度处理,以抛物线方程y=a bx cx^2拟合世代存活率（S）、种群趋势指数（I）、净生殖率（R0）和内禀增长为（rm）,在24℃、27℃和30℃温度下,白蜡门阔柄跳小蜂的种群趋势指数I＞1,内禀增长力rm＞0,种群数量逐代增加,种群加倍时间分别为15、16和23d,21℃时I≈1,rm≈0,种群数量基本保持不变,18℃和33℃时I＜1,rm＜0,种群数量出现负增长,15℃雌蜂不产卵,不能繁殖后代。     

阔柄跳小蜂属一新种(膜翅目,跳小蜂科)

记述了阔柄跳小蜂属Metaphycus 1新种,阿土阔柄跳小蜂Metaphycus aretus sp.nov.(膜翅目,跳小蜂科),并提供了新种的主要形态特征图.阿土阔柄跳小蜂属于zebratus种团,与M.maculipennis形态相似,但该种柄节外侧除白色背脊外,中间无白色条带;前额宽约为1/3头宽;产卵器长约为第3产卵瓣长5.5 ～5.9倍.研究标本保存在中国科学院动物研究所国家动物标本馆.     

斑翅食蚧蚜小蜂的生物学特性

斑翅食蚧蚜小蜂Coccophagus ceroplastae是橡副珠蜡蚧Parasaissetia nigra的重要内寄生蜂。对斑翅食蚧蚜小蜂的形态特征进行了描述,在实验室条件下观察了斑翅食蚧蚜小蜂的行为、发育、存活、繁殖等生物学特性。结果表明:斑翅食蚧蚜小蜂幼虫分3龄,完成一个世代需21-26d。卵巢左右成对,各由3条卵巢管组成,为发育成熟型,成虫期补充营养和发育时间对抱卵量的影响不明显。羽化后即可进行交配,交配时间2-3s,雄蜂有竞争交配行为,交配对雌蜂产卵有显著刺激作用。产卵行为有寻找、寄主检查、产卵器刺探、产卵、产卵针拔出等步骤,存在过寄生现象。羽化主要是在08:00-10:00,温度、相对湿度、光照对其羽化节律均有影响,温度升高羽化提前,且相对集中;相对湿度在20%-90%范围内,随湿度的升高成虫羽化高蜂延后;而光照时间过长或过短均可使斑翅食蚧蚜小蜂的羽化相对分散。随着温度的升高,雌成蜂的寿命逐渐缩短;补充营养能延长成虫寿命,取食10%蔗糖的寿命最长,清水和无补充营养寿命短。     

中国阔柄跳小蜂属一新种（膜翅目：跳小蜂科）

记述了阔柄跳小蜂属1新种：廖氏阔柄跳小蜂Metaphycus liaoi sp．nov．,并给出了其形态特征图。廖氏阔柄跳小蜂与Mstagnarum很相似,但廖氏阔柄跳小蜂雌虫柄节最宽处在基半部,生殖器明显长于中足胫节,雄虫第1索节短于梗节,柄节长约为宽的3倍;而M.stagnarum雌虫柄节最宽处在端半部,生殖器短于中足胫节,雄虫第1索节明显长于梗节,柄节长约为宽的4倍。研究标本,包括正模,均保存在中国科学院动物研究所动物标本馆。正模：♀,北京市海淀区,2007-V-20～23,育自Eriococcus abeliceae,武三安采;副模：12♀♀,8♂♂,同正模。词源：种名是为纪念已故廖定熹教授,他对中国跳小蜂分类研究做出了重大贡献。     

日本食蚧蚜小蜂的交配行为及雌蜂生殖系统观察

日本食蚧蚜小蜂Coccophagus japonicus Compere是橡副珠蜡蚧Parasaissetia nigra Nietner的优势寄生蜂之一,为明确其交配行为及雌蜂生殖系统构成,本研究在室内观察了该蜂的交配行为、雄蜂交配能力、雌蜂生殖系统等。结果表明:日本食蚧蚜小蜂的交配过程可分为交配前行为、交配、交配后行为3个阶段,整个交配过程平均时间为76.2 s,其中,交配时间为20.6 s;小蜂羽化当天即可交配,雌、雄蜂具有多次交配的习性,雄蜂的交配能力随其日龄的增加而减弱,1日龄的雄蜂交配能力最强,为6.3次/d,雄蜂一生平均能交配36.9次;雌蜂的生殖系统由1对卵巢、1对侧输卵管、1条中输卵管、1个受精囊和外生殖器等组成,卵巢管数量存在变异,其中95.78%雌蜂卵巢具6(3+3)条卵巢管,2.78%雌蜂卵巢具5(3+2)条卵巢管,1.22%的雌蜂卵巢具7(3+4)条卵巢管,0.22%的雌蜂卵巢是具4(2+2,1+3)条卵巢管,还有极个别的雌蜂仅有1个卵巢,由3条卵巢管组成。研究结果表明日本食蚧蚜小蜂有多次交配习性,卵巢存在一定变异。     

橡胶盔蚧寄生蜂种群消长动态研究及可利用分析

通过定点调查橡胶盔蚧Parasaissetia nigra Nietner和寄生蜂种群消长动态及农药影响橡胶盔蚧寄生蜂寄生率的试验,分析评价寄生蜂在控制橡胶盔蚧上的可利用性及探讨橡胶盔蚧的综合防治技术.结果表明:寄生蜂种群消长变化趋势与橡胶盔蚧基本一致.橡胶盔蚧成虫和若虫的发生以及寄生蜂种群寄生率周年均出现3个高峰,成...     

黄猄蚁对橡胶盔蚧种群消长的影响

调查西双版纳地区黄猄蚁OecophyllasmaragdinaFabricius对橡胶盔蚧Parasaissetianigra(Nietner)种群数量和寄生蜂的影响。结果表明:黄猄蚁对橡胶盔蚧种群消长及寄生蜂均有影响。"有蚂蚁"枝条上介壳虫种群数量显著高于"无蚂蚁"枝条。"有蚂蚁"枝条介壳虫死亡率和寄生蜂都显著低于"无蚂蚁"枝条。说明黄猄蚁的存在影响了橡胶树介壳虫的种群繁殖率和死亡率。建议在今后综合防治中,充分利用蚂蚁与橡胶树介壳虫关系。通过驱逐橡胶树上的蚂蚁来有效遏制介壳虫的发生。     

西双版纳橡胶盔蚧与蚂蚁的相互关系

在云南省植胶区采用2种不同方法对橡胶盔蚧共生蚂蚁种类进行调查.共采集到蚂蚁22种,隶属4个亚科15个属.优势种为黄猄蚁(Oecophylla smaragdina).大田普查发现,有蚂蚁存在的橡胶树,受橡胶盔蚧危害的几率较高.为了解橡胶盔蚧与蚂蚁的相互关系,选择2棵有黄猄蚁和橡胶盔蚧的橡胶树进行调查.结果表明,橡胶盔蚧数量与蚂蚁数量呈正相关,蚂蚁数量越大,橡胶盔蚧危害越严重;同时,离蚁巢的距离也影响着橡胶盔蚧的数量,离蚁巢越近,橡胶盔蚧数量越大.蚂蚁隔离后,橡胶盔蚧第2代死亡率和寄生蜂的寄生率降低,从而增加了橡胶盔蚧的种群数量.结果验证,蚂蚁的存在确能保护橡胶盔蚧,它们之间为共生关系.     

Scanning Electron Microscopy Studies of the Antennal Sensilla of Metaphycus parasaissetiae Zhang & Huang (Hymenoptera: Encyrtidae)

Metaphycus parasaissetiae Zhang & Huang (Hymenoptera: Encyrtidae) is an important adult parasitoid of Parasaissetia nigra Nietner (Hemiptera: Coccoidea). The external morphology of the antennal sensilla of male and female M. parasaissetiae was examined using scanning electron microscopy. The geniculate antennae of male and female M. parasaissetiae were composed of a scape with a basal radicula, a barrel-shaped pedicel, and a long flagellum. Twelve morphologically distinct types of sensilla were identified, including multiporous placoid sensilla, campaniform sensilla, finger-like sensilla, multiporous basiconic sensilla (BS-1), three aporous types of basiconic sensilla (BS-2, BS-3, and BS-4), two types of aporous trichoid sensilla (TS-1 and TS-3), a type of multiporous trichoid sensilla (TS-2), and two types of sensilla chaetica (CH-1 and CH-2). Sex dimorphism in the sensilla composition of M. parasaissetiae is also observed. Major differences between the sexes were found in the number, distribution, shape, structure, and size of the identified sensilla. We also discuss on the functional aspects of these sensilla to elucidate the mechanisms involved in host searching and courtship behavior of M. parasaissetiae.     

Larval morphology of Metaphycus flavus and its role in host attachment and larval cannibalism

Metaphycus flavus (Howard) (Hymenoptera: Encyrtidae) is a facultatively gregarious endoparasitoid of soft scales (Hemiptera: Coccidae). When it develops in superparasitised hosts, the larvae often attack and consume brood mates six or more days post oviposition. Under our laboratory conditions (25±1°C and 14 hours of light followed by 18±1°C and ten hours of darkness in 50-70% R.H.), M. flavus eggs hatched three days after oviposition. Measurements of the mandibles and tentorium indicate there are four larval instars, and M. flavus reaches the fourth instar by day six post oviposition, and pupates on day eight. Thus, cannibalism among M. flavus larvae occurs during the fourth instar. During this instar, M. flavus larvae separate from their attachment to the scale cuticle, to which they were tethered by a respiratory structure during the previous three larval instars. Once detached, they are free to move within the scale, which increases the probability of larval encounters and aggressive behaviours. Moreover, the mandibles of the fourth instar are better adapted for fighting than are those of the first three larval instars, since they are larger and more sclerotized. The cranium and mouthparts of M. flavus have four different types of sensory organs, some of which are almost certainly olfactory, an unexpected function for a larva that presumably is surrounded by an aqueous medium where gustatory sensilla would seem to be more appropriate. The cranium also bears two pairs of what appear to be secretory pores.     

Constraints on host use by a parasitic plant

Consumers do not always utilize all suitable hosts. Understanding why parasitic plants do not always parasitize potentially suitable hosts requires a better understanding of the constraints that limit host use by parasitic plants. In Texas salt marshes, the parasitic plant Cuscuta indecora rarely parasitizes three hosts that support vigorous growth in the greenhouse. We identified three constraints on host use by C. indecora. First, a mismatch between the phenology of C. indecora and some suitable hosts meant that these hosts were not abundant when C. indecora was growing most vigorously, and therefore were underutilized. Second, C. indecora preferentially parasitized tall plants versus short ones, causing relatively short species to be underutilized. Third, C. indecora overwinters in some perennial hosts but has to reinfect annual hosts each year, causing annuals and perennials that do not support overwintering to be underutilized. In combination, these constraints, which reflect the general lack of mobility of parasitic plants relative to herbivores, remove half of the potential host species from the actual diet of C. indecora, and therefore likely represent a major limitation on the success of this parasite. Similar constraints are likely to limit the realized host range of many parasitic plants and select for generalized diet preferences.     

A parasitic selfish gene that affects host promiscuity

Selfish genes demonstrate transmission bias and invade sexual populations despite conferring no benefit to their hosts. While the molecular genetics and evolutionary dynamics of selfish genes are reasonably well characterized, their effects on hosts are not. Homing endonuclease genes (HEGs) are one well-studied family of selfish genes that are assumed to be benign. However, we show that carrying HEGs is costly for Saccharomyces cerevisiae, demonstrating that these genetic elements are not necessarily benign but maybe parasitic. We estimate a selective load of approximately 1–2% in ‘natural’ niches. The second aspect we examine is the ability of HEGs to affect hosts'' sexual behaviour. As all selfish genes critically rely on sex for spread, then any selfish gene correlated with increased host sexuality will enjoy a transmission advantage. While classic parasites are known to manipulate host behaviour, we are not aware of any evidence showing a selfish gene is capable of affecting host promiscuity. The data presented here show a selfish element may increase the propensity of its eukaryote host to undergo sex and along with increased rates of non-Mendelian inheritance, this may counterbalance mitotic selective load and promote spread. Demonstration that selfish genes are correlated with increased promiscuity in eukaryotes connects with ideas suggesting that selfish genes promoted the evolution of sex initially.     

Vibratory stimuli in host location by parasitic wasps

Parasitic wasps use a broad spectrum of different stimuli for host location and host acceptance. Here we review the published evidence for the use of mechanical stimuli, i.e. substrate born vibrations which are invariably regarded as vibrotaxis. We propose a set of criteria to class behavioural reactions as vibrotaxis or vibrokinesis and characterize 14 studies reporting the use of host-associated vibrations by parasitoids. The studies are compared concerning (i) experimental design; (ii) characterisation of vibrational signals; and (iii) progress of the parasitoid towards the host.The recent experimental development based on new measurement techniques shows the growing body of evidence that host-associated vibrations are exploited by parasitic wasps. Nevertheless a definite proof for vibrotaxis is still lacking. To assess the exact mechanisms by which parasitoids use vibrations bioassays comparing reactions to natural and artificially generated signals are needed. Vibrotaxis as well as vibrokinesis are both helpful host location strategies for parasitoids foraging in a multimodal environment. At the community level they may lead to niche differentiation.