美丽青背姬小蜂寄生和繁殖特性研究

美丽青背姬小蜂Chrysonotomyia formosa(Westwood)是美洲斑潜蝇的优势天敌,在美洲斑潜蝇的自然控制中发挥着非常重要的作用.本文对其寄生和繁殖特性进行了研究,结果表明:美丽青背姬小蜂主要将卵产于寄主幼虫的腹部,1头寄主幼虫体内可产1～5粒卵,但只有1粒卵能完成发育成为成蜂;不同温度下,雌蜂的繁殖能力不同,其中雌蜂在23℃时有最大的产卵量和最高的致死寄主个体数;提供10%的蜂蜜水可以显著提高雌蜂对寄主的寄生数、产卵量、刺死寄主数和总致死寄主数;美丽青背姬小蜂也能进行产雄孤雌生殖;营孤雌生殖的雌蜂与有性生殖的雌蜂在寿命、寄生寄主数、产卵数、刺死寄主数和总致死寄主数之间差异不显著.     

小菜蛾主要寄生性天敌——菜蛾绒茧蜂与菜蛾啮小蜂间的相互作用

在28℃下,以小菜蛾3龄幼虫作寄主,研究了菜蛾绒茧蜂与菜蛾啮小蜂间的相互关系．当寄主供2种蜂同时产卵寄生时,与只供1种蜂时相比。绒茧蜂的寄生率无显著变化,而啮小蜂的寄生率则显著下降;2种蜂的合计寄生率与任一种蜂单独存在时相比无显著差异．当寄主先供绒茧蜂寄生,再供啮小蜂寄生时,绒茧蜂的成功寄生率不受影响,而啮小蜂的寄生率仅为8％～13％;啮小蜂能寄生在寄主体内的绒茧蜂高龄幼虫．绒茧蜂能寄生已被啮小蜂寄生的寄主幼虫,其子代部分个体能正常发育至成虫羽化．当已被绒茧蜂寄生和未被寄生的寄主同时存在时,啮小蜂主要寄生未被寄生的寄主．表明绒茧蜂具有竞争优势。但这种优势可因啮小蜂的寄生而被削弱．     

椰心叶甲啮小蜂的繁殖生物学研究

对椰心叶甲啮小蜂羽化、求偶、交配、产卵、繁殖现象进行了观察研究。结果表明,补充营养对雌蜂的寿命和繁殖力均有影响。没有补充营养的情况下,雌蜂的平均寿命为2.48 d,一生可产21.43粒卵;每天补充10%蜜糖水,且雌蜂与寄主(椰心叶甲初蛹)比例为1:3时,雌蜂平均寿命为13.43 d,一生可产53.6粒卵;每天补充10%蜜糖水,且雌蜂与寄主(椰心叶甲初蛹)比例为1:1时,雌蜂平均寿命为14.78 d,一生可产42.5粒卵。椰心叶甲啮小蜂对水椰八角铁甲蛹的寄生率为82.25%,平均每寄主出蜂量为12.24头。     

寄主大小对副珠蜡蚧阔柄跳小蜂产卵选择及繁殖的影响

为明确寄主体型大小对副珠蜡蚧阔柄跳小蜂产卵选择及繁殖的影响,在室内观察了副珠蜡蚧阔柄跳小蜂在不同大小的橡副珠蜡蚧上的产卵量、寄生率、发育历期及性比。结果表明:在选择性和非选择性的产卵试验条件下副珠蜡蚧阔柄跳小蜂对中型个体寄主(长4.0 mm,宽3.4 mm)的寄生率最高;小蜂的产卵量在选择性试验时,以大型寄主(长4.8 mm,宽4.0 mm)体内的最高(67.0粒),非选择性试验时,以中型寄主(长4.0 mm,宽3.4 mm)体内的最高(131.0粒),小型寄主(长3.2 mm,宽2.9 mm)体内产卵量最少(61.5粒);副珠蜡蚧阔柄跳小蜂后代出蜂数与寄主体型的大小呈显著正相关,雌性比则随寄主体型的增大而增减小,发育历期则受寄主体型的影响不明显。综上所述,副珠蜡蚧阔柄跳小蜂雌蜂能够根据寄主质量来调整产卵量及后代性比,以使后代适应度最大化。     

哈氏啮小蜂雌蜂的繁殖生物学特性

哈氏啮小蜂Tetrastichus hagenowii（Ratzeburg）是卫生害虫蜚蠊的重要天敌昆虫, 能寄生多种蜚蠊种类的卵荚, 被认为是控制蜚蠊危害最具潜力的天敌昆虫。本文对哈氏啮小蜂雌蜂的繁殖生物学特性进行了系统研究。结果表明: 哈氏啮小蜂行孤雌生殖和两性生殖的繁殖方式, 两性生殖其子代雌蜂所占比例为46.02%, 而孤雌生殖其子代均为雄性。经解剖镜检证实: 雌蜂发育至性成熟时的两侧卵巢结构呈现为, 每侧卵巢有8~12根卵巢管, 每根卵巢管怀卵量约1~6粒。结果发现雌蜂发育日期影响其怀卵数量, 1日龄哈氏啮小蜂怀卵量低, 平均为45.2粒/♀; 2日龄哈氏啮小蜂怀卵量较高, 平均为80.1粒/♀。哈氏啮小蜂羽化后即性成熟产卵, 产卵期为4~11 d, 日产卵量为0.86~7.57粒/♀, 单雌一生平均寄生1枚美洲大蠊卵荚。供试寄主卵荚密度是影响哈氏啮小蜂寄生率的重要因素, 在蜂卵荚比例为1∶5, 1∶3, 1∶2, 1∶1, 2∶1和3∶1范围内, 哈氏啮小蜂对卵荚的寄生率随着雌蜂数量与寄主卵荚比例的提高而增加, 然单雌寄生卵荚数量却呈下降趋势。     

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。     

啮小蜂毒液对寄主亚洲玉米螟蛹发育的影响

假寄生和毒液注射实验表明啮小蜂Tetrastichussp .毒液能永久麻痹亚洲玉米螟蛹Ostriniafurnacalis,较高剂量的毒液对亚洲玉米螟蛹有不同程度的麻痹作用。麻痹的蛹在室温下较长时间内不腐烂和干化。低剂量毒液能延长亚洲玉米螟蛹期 1～ 3d ,导致畸形成虫。啮小蜂初产卵转移寄主实验证实毒液可以帮助啮小蜂卵在亚洲玉米螟蛹体内的发育 ,啮小蜂初产卵在转移寄主体内发育到羽化时间为 2 5d ,比它们在原寄主内的羽化时间增加 8d左右 ,初产蜂卵与 1个毒液储液囊当量的毒液同时注入转移寄主体内 ,初产卵的羽化时间明显缩短 ,死亡率降低     

营养对不同地理种群周氏啮小蜂生物学特性的影响

【目的】研究补充营养对周氏啮小蜂海南本土地理种群和北京地理种群的生物学参数是否有差异。【方法】设置不同的营养(10%蜂蜜、10%蔗糖、10%葡萄糖、水、空白)分别饲喂周氏啮小蜂,统计2个地理种群的寄生率、羽化率、出蜂量、寿命。【结果】2个地理种群的周氏啮小蜂羽化后不久即可进行交配,补充10%蜂蜜、10%蔗糖、10%葡萄糖能显著提高2个地理种群的寄生率、羽化率、出蜂量、雌雄蜂寿命,补充不同的营养对两个地理种群的雌雄比、发育历期的影响差异不显著;饲喂10%蜂蜜的海南地理种群寄生率最高(84.60%),饲喂10%葡萄糖的海南地理种群羽化率最高(97.47%),饲喂10%葡萄糖的海南地理种群出蜂量最高(60.03头),饲喂10%葡萄糖的海南地理种群雌、雄蜂的寿命均为最高,分别为9.13和8.53d。营养和地理种群的交互作用对周氏啮小蜂雄蜂的寄生率、羽化率、出蜂量、雌雄比、雌雄蜂寿命具有显著影响,而对周氏啮小蜂的发育历期无显著影响。【结论】补充营养可不同程度促进周氏啮小蜂生殖力、寿命及寄生率,对寄生蜂繁育和利用其进行生物防治具有一定的意义。     

椰心叶甲啮小蜂(Tetrastichus brontispae)实验种群生命表的编制

通过解剖椰心叶甲被寄生僵虫统计椰心叶甲啮小蜂未成熟期的发育历期、存活率与生殖力数据,编制了椰心叶甲啮小蜂的实验种群生命表.常温下椰心叶甲啮小蜂卵、幼虫和蛹的历期分别为3.1、5.0 d和9.3 d,啮出前期为2.1 d.卵、幼虫和蛹的存活率分别为0.9184、0.9521和0.9818,椰心叶甲啮小蜂的成虫羽化率为0.9,单雌产卵量为23.78粒,种群趋势指数为12 45.通过此生命表的组建,讨论了生命表中种群趋势指数(I)与生殖力表中净增殖力(R0)的关系,认为这两个概念本为同一含义,应该合并.此外,在成虫寿命大于等于2d的情况下,成虫逐日存活率与逐日产卵概率乘积的和小于1,且成虫寿命越长其值越小,结果导致在不考察成虫逐日存活率与逐日产卵概率的情况下种群趋势指数被严重高估,因此组建任何形式的生命表都应考察并计入成虫逐日存活率与逐日产卵概率.     

周氏啮小蜂(海南种群)对椰子织蛾的寄生功能反应

【目的】周氏啮小蜂(海南种群)是寄生椰子织蛾蛹期的本土天敌。研究周氏啮小蜂(海南种群)对椰子织蛾的功能反应,能为该蜂室内扩繁和室外控害利用提供基础。【方法】在室内观察周氏啮小蜂(海南种群)寄生行为基础上,研究了营养(10%蜂蜜)、寄主蛹(初、中、晚)期对周氏啮小蜂(海南种群)寄生功能反应的影响。【结果】镜下观察1头周氏啮小蜂(海南种群)可寄生多头椰子织蛾蛹,寄生量随寄主密度的增大而增加,但当寄主密度达到一定程度后,其增长率随寄主密度的增大逐渐减缓,属于HollingⅡ功能反应。在无营养条件下,周氏啮小蜂(海南种群)对椰子织蛾初、中、晚期蛹的理论最大寄生量分别为1.5、1.4、1.2头·d~(-1);在10%蜂蜜饲喂条件下,周氏啮小蜂(海南种群)对椰子织蛾初、中、晚期蛹的理论最大寄生量分别为1.8、1.7、1.3头·d~(-1)。【结论】HollingⅡ型拟合结果表明,椰子织蛾初期蛹是周氏啮小蜂(海南种群)寄生的最佳时期,补充营养能够提高椰子织蛾的寄生力。     

On the fauna of chironomidae (Diptera) of the Hrazdan Basin (Armenia)

A faunistic review of larvae and pupae of chironomid midges (Diptera, Chironomidae) from 15 habitats in the Hrazdan River valley (Armenia) is presented. The revealed fauna includes 40 species from 20 genera and 6 families and tribes. Diploid chromosome numbers are specified for 24 species from 13 genera and 4 subfamilies; 23 species from 14 genera and 4 subfamilies are reported from the region for the first time. Predominant oligotrophic status is confirmed for most of the reservoirs studied.     

On the Structure of the Corpuscles of de Quatrefages (Branchiostoma lanceolatum (P))

Corpuscles of de Quatrefages in the rostral connective tissue of amphioxus have been serially sectioned and examined in the electron microscope. It is shown that each corpuscle is composed of one or a few main cells separated and enveloped by sheath cells. From the main cell two cilia protrude into a lumen formed by a bulge in the sheath. The ciliation of the main cell and its axonic continuation into one of the associated nerves suggests that this cell is a primary sensory neurone and the corpuscles of de Quatrefages probably mechanoreceptors.     

On the discussion of the wing venation of (Archae)Orthoptera (Insecta)

Alternative current approaches to homology and nomenclature of the insect wing venation are discussed. The differences between the opposing viewpoints are found to be not as deep as they have sometimes been supposed to be, and more so, there are some observations that could help to smooth current contradictions. However, this requires an understanding of the evidence presented by the disputants and, particularly, an understanding of their terminology.     

Dioecism of the genusCallicarpa (Verbenaceae) in the Bonin (Ogasawara) Islands

The morphology and function of the flowers of three species of the genusCallicarpa, C. glabra, C. nisnimurae andC. subpubescens, endemic to the Bonin Islands, revealed that all three species were dioecious. Male plants had short-styled flowers with sterile ovaries, while female plants had long-styled flowers with non-germinating inaperturate pollen grains. Such dioecism has never been reported from the family Verbenaceae. This curious sexual system with non-germinating pollen grains may have been maintained as a reward to insect pollinators.     

Catecholaminergic Neurons in the Nervous System of Neorhabdocoela (Turbellaria(

Mapping of catecholaminergic (CAergic) neurons in the nervous system has been performed in 5 species of turbellarians of the order Neorhabdocoela: in three species of typhloplanides, Mesostoma lingua, Bothromesostoma essenii, and Rhynchomesostoma rostratum, and in two species of Dalyellioida, Castrella truncata and Gieysztoria cuspidata. In spite of an essential diversity of their orthogones, the number of cerebral neurons varies insignificantly: from 4 to 5 pairs at 3 variants of geometry of their arrangement. In the presence of the medial paddle-shaped outgrowth of neuropil, two pairs of anterior cerebral neurons are located on its both sides, while 2 pairs of posterior neurons, in the inferior lateral regions of neuropil. The absence of the medial outgrowth and a stretching of neuropil provided a fan-shaped arrangement of cerebral neurons behind the eyes and on the sides of the pharynx. The three-store arrangement of cerebral neurons is revealed in the presence of a cone-shaped trunk at the anterior end of the body, when all 5 pairs of neurons are connected to each other with longitudinal and transverse processes. The rosette-shaped pharynx is innervated with five pharyngeal nerves, while the barrel-shaped pharynx, with six nerves, each of them with one bipolar neuron. From 2 to 5 pairs of neurons of the L-group were revealed. Homology of the L-group neurons has been confirmed in the order Neorhabdocoela. The total number of CAergic neurons varies from 24 to 29.