刺粉虱黑蜂触角感器的扫描电镜观察

采用扫描电镜观察了刺粉虱黑蜂Amitus hesperidum Silvestri触角。结果表明,在雌雄蜂的触角上共存在着7种感觉器,分别为Bhm氏鬃毛、毛形感觉器、板形感觉器、腔锥形感器、柱形感觉器、栓锥形感觉器。对触角感觉器的形态、分布进行了描述。雌雄触角有性二型现象,主要表现在毛形感器数量差异明显,板形感器分布不同,栓锥形感器只在雌虫上发现。     

六斑月瓢虫触角及感觉器扫描电镜观察

[目的] 明确六斑月瓢虫雌雄成虫触角感觉器种类、分布及形态特征。[方法] 利用扫描电子显微镜对六斑月瓢虫雌、雄成虫触角形态及触角感受器超微结构进行观察。[结果] 六斑月瓢虫成虫触角由柄节、梗节和鞭节组成,柄节长度与宽度显著大于梗节长度与宽度;鞭节分为9个亚节,末端3节横向膨大呈锤状。雌雄成虫触角上共有8种感觉器:刺形感觉器(SC)、毛形感觉器(ST)、锥形感觉器(SB)、腔形感觉器(CaS)、钟形感觉器(CS)、哑铃形感觉器(DS)、香肠形感觉器(SS)及B?hm氏鬃毛感觉器(BB)。以毛形感觉器和刺形感觉器分布最广,遍布触角;B?hm氏鬃毛仅存在于触角柄节与梗节;触角鞭节第9亚节顶端密布7种触角感觉器。六斑月瓢虫雌雄成虫触角长度、触角感觉器类型及分布无显著差异。[结论] 六斑月瓢虫成虫触角上共有8种感觉器,其触角可能具有感知机械刺激、识别化学信息素及感受温湿度变化的作用。本研究为进一步了解六斑月瓢虫触角与其行为间的关系提供基础资料。     

侧沟茧蜂触角感觉器的扫描电镜观察

扫描电镜观察表明:侧沟茧蜂Microplitis sp.的触角上存在5种感觉器,分别为毛状感觉器A型、B型、C型,槽状感觉器,锥形乳头状感觉器,刺形感觉器和钟形感觉器.对触角感觉器的形态和分布进行了描述,并对两性间的差别进行了讨论,为研究该蜂寻找生境和寄生行为提供依据.     

分月扇舟蛾触角感觉器的扫描电镜观察

利用扫描电镜对分月扇舟蛾Clostera anastomosis(L.)成虫触角感觉器的形态、结构进行了观察。扫描电镜观察结果表明,分月扇舟蛾触角由柄节、梗节和鞭节组成,触角外侧面覆盖有鳞片,绝大部分触角感觉器位于触角的腹面和外侧面。雌、雄蛾触角上均存在以下8种感觉器,即毛形感器、刺形感器、腔形感器、腔锥形感器、栓锥形感器、锥形感器、柱形感器和鳞形感器。各种感觉器在雌、雄蛾触角上的分布大体相同,但数量有明显的区别。     

芒果横线尾夜蛾触角感觉器扫描电镜观察

采用扫描电镜技术对芒果横线尾夜蛾触角感觉器进行了观察和研究。结果表明,芒果横线尾夜蛾成虫触角上有5种类型的感觉器,分别为毛形感觉器、刺形感觉器、锥形感觉器、腔锥形感觉器和柱形感觉器。这些感觉器在成虫中存在雌雄二型性,其中雌雄虫都具有毛形感觉器Ⅰ型和Ⅱ型、刺形感觉器、锥形感觉器Ⅰ型和腔锥形感觉器等四种类型的感觉器,其中以毛形感觉器最多,约占全部感觉器的72%。而锥形Ⅱ型和柱形感觉器只存在于雄虫触角上。     

玉龙蝠蛾触角感觉器的扫描电镜观察

本文报道玉龙蝠蛾 Hepialus yulongensis Liang 触角感觉器种类、形态和分布的扫描电镜观察结果。蝠蛾触角呈丝状,由柄节、梗节和21—27个鞭节组成,总长2.3—2.7毫米,柄节比以后各节长,触角表面缺少隆起的网纹。触角感觉器计有七种,其名称为毛形感器、刺形感器、腔锥感器、锥形感器、鳞形感器、Bohm氏鬃毛及仅出现于雄蛾的钟形感器。根据中心栓的长度,腔下陷的深度和直径,腔锥感器基本上可分为长栓和短栓两种形态类型,腔的周围都无向内倾斜的缘栓;毛形感器可进一步分为A型和B型;Bohm氏鬃毛数量多,主要分布于柄节、梗节,但在端节也能见到。     

虫草蝠蛾触角感觉器的扫描电镜观察

本文报道冬虫夏草的三种寄主昆虫白马蝠蛾(Hepialus baimaensis)、 人支蝠蛾(H.Renzhiensis)和中支蚯蛾(H.Zhongzhiensis)触角感觉器种类、形态和分布的扫描电镜观察结果。三种蝠蛾触角表面均缺少网状覆盖物。计有七种感觉器,名称为毛形感器、刺形感器、锥形感器、腔锥感器、Bohm氏鬃毛、鳞形感器和钟形感器。毛形感器分A和B型,数量最多。鞭节上每节具有2-3只刺形感器和l-5只锥形感器。腔锥感器分为长栓和短栓两种形态类型,腔周围都无缘栓。 Bohm氏鬃毛主要分布于基节,数量较多。钟形感器仅在雄蛾触角上见到。各类感觉器在种间无明显差异。     

草地螟触角化学感受器的电镜观察

应用扫描电镜对草地螟成虫触角的外部形态结构进行观察的结果表明 :成虫触角存在着 5种感觉器 ,即毛形感器、刺形感器、腔锥感器、锥形感器和耳形感器 ,其中以毛形感器数目最多 ,刺形感器分为Ⅰ型和Ⅱ型。并对草地螟触角两性差异及与其它相近昆虫的差异进行了讨论。     

荔枝异形小卷蛾(鳞翅目:卷蛾科)触角的扫描电镜观察

荔枝异形小卷蛾在格木纯林危害极为严重,导致其难以成林,目前对其形态学和生物学等方面研究极少,限制其开展营林技术防控和生物防控技术等应用。本研究利用扫描电镜对荔枝异形小卷蛾雌雄成虫的触角外部形态和感器进行了观察。结果表明:荔枝异形小卷蛾触角为线状,成虫触角上存在着7种感觉器,即:刺形感器、毛形感器、腔锥形感器、栓锥形感器、耳性感器、鳞形感器、锥形感器。绝大部分触角感觉器存在于梗节和鞭节上,并且多处于触角的腹面和侧面。其中毛形感器是最主要的感器,数量较大且分布较广。通过研究成虫触角感器为探索利用信息素防治该虫提供了理论和技术支撑。     

昆虫嗅觉机理的几种假说

长期以来,人们已经知道昆虫是借助于头部的一对触角来辨别生境中的各种化学信息。有关昆虫嗅觉方面的研究可追溯到1837年莱费伯首先发现昆虫雌雄间的通信联系依赖于雌蛾腹部释放出来的化学气味。一个多世纪以来,嗅觉机理的研究主要局限于阐述触角是嗅觉的主要感觉器宫,描述触角的形态以及化学分子和嗅觉器官间的相互关系。自从1957年舒奈德采用电生理方法将氯化银电极插入雄性家蚕触角两端,成功地记录了触角电位后,许多研究者广泛采用触角电     

EFFECTS OF GOSSYPOL ON GROWTH OF THE COTTON BOLLWORM AND DEVELOPMENT OF ITS PARASITOID CAMPOLETIS CHLORIDEAE*

Abstract The effects of gossypol, an important allelochemical in cotton, on growth of the cotton bollworm Helicoverpa armigera (Hubner) and development of its endoparasitoid Campoletis chlorideae (Uchida) in Huanghe River Valley were studied. Growth of H. armigera larvae was accelerated by adding 0.1% gossypol in the artificial diet, causing 10.75% reduction of the vulnerable period to C. chlorideae while the suppression activity of 0. 5 % gossypol to H. armigera larvae prolonged the vulnerable period by 28.15%. Negative effects of gossypol on the development of the parasitoid were demonstrated by using the artificial diet and cotton varieties WD-151 (glandless) and HG-BR-8 (glanded). Gossypol at 0.1% concentration in artificial diet did not remarkably increase the body weight of adult wasp, but significantly extended the egg-larval time and shortened the pupal time; 0. 5% gossypol and HG-BR-8 remarkably reduced the body weight of adult wasp, also significantly prolonged the egg-larval period and decreased the pupal period. Finally, the coordinate application of high gossypol resistant cotton varieties and C. chlorideae in H. armigera control is discussed.     

THE FUNCTION OF THE BRAIN IN LOCOMOTION OF THE POLYCLAD WORM,YUNGIA AURANTIACA

Coordinated swimming movements in Yungia are not dependent upon the presence of the brain. The neuromuscular mechanism necessary for spontaneous movement and swimming is complete in the body of the animal apart from the brain. Normally this mechanism is set in motion by sensory stimulation arriving by way of the brain. The latter is a region of low threshold and acts as an amplifier by sending the impulses into a great number of channels. When the head is cut off these connections with the sensorium are broken, consequently peripheral stimulation does not have its usual effect. If, however, the motor nerves are stimulated directly as by mechanical stimulation of the median anterior region, then swimming movements result. Also if the threshold of the entire nervous mechanism is lowered by phenol or by an increase in the ion ratios See PDF for Equation and See PDF for Equation then again peripheral stimulation throws the neuromuscular mechanism into activity and swimming movements result.     

EFFECTS OF GENETIC KNOCK‐DOWN OF ORGANIC ANION TRANSPORTER GENES ON SECRETION OF FLUORESCENT ORGANIC IONS BY MALPIGHIAN TUBULES OF Drosophila melanogaster

An earlier study has shown that RNAi knock‐down of a single organic anion transporter (OAT) gene in the principal cells of Drosophila Malpighian tubules is associated with reductions in the expression of multiple, functionally related genes. In this study, we measured the rates of secretion of four fluorescent ions by tubules isolated from flies expressing targeted RNAi knock‐down of specific OAT genes. Droplets secreted by isolated tubules set up in the Ramsay assay were collected in optically flat capillary tubes and the concentrations of fluorescent ions were determined by confocal laser scanning microscopy. Reductions in the expression of organic anion (OA) transporting polypeptide 58Dc (OATP; CG3380) were associated with reduced secretion of the OAs fluorescein and Texas Red. Reduction in the expression of Drosophila multidrug resistance associated protein (dMRP; CG6214) was correlated with reduced secretion of the P‐glycoprotein substrate daunorubicin. Secretion of the organic cation quinacrine was unaffected by reduced expression of OATP, dMRP, or a multidrug efflux transporter (MET; CG30344). The results highlight the difficulties of assigning a rate‐limiting role in transport of a specific OA to a single membrane transporter.     

Conversion of progesterone-1,2-3H to 5β-pregnane-3,20-dione by brain tissue

The presence of a 5β-reductase acting to convert progesterone to 5β-pregnane-3,20-dione is described in the soluble 105,000 × $\text{g}$ fraction of a preparation of dog cerebral cortex. The function of this enzymatic activity is obscure but may be important in regulation of sensorium. 5β-pregnane compounds are potent depressors of the central nervous system.     

Phylogenetic analysis of Geotrupidae (Coleoptera, Scarabaeoidea) based on larvae

Abstract. Thirty‐eight characters derived from the larvae of Geotrupidae (Scarabaeoidea, Coleoptera) were analysed using parsimony and Bayesian inference. Trees were rooted with two Trogidae species and one species of Pleocomidae as outgroups. The monophyly of Geotrupidae (including Bolboceratinae) is supported by four autapomorphies: abdominal segments 3–7 with two dorsal annulets, chaetoparia and acanthoparia of the epipharynx not prominent, glossa and hypopharynx fused and without sclerome, trochanter and femur without fossorial setae. Bolboceratinae showed notable differences with Pleocomidae, being more related to Geotrupinae than to other groups. Odonteus species (Bolboceratinae s.str.) appear to constitute the closest sister group to Geotrupinae. Polyphyly of Bolboceratinae is implied by the following apomorphic characters observed in the ‘Odonteus lineage’: anterior and posterior epitormae of epipharynx developed, tormae of epipharynx fused, oncyli of hypopharynx developed, tarsal claws reduced or absent, plectrum and pars stridens of legs well developed and apex of antennal segment 2 with a unique sensorium. A ‘Bolbelasmus lineage’ is supported by the autapomorphic presence of various sensoria on the apex of the antennal segment, and the subtriangular labrum (except Eucanthus). This group constituted by Bolbelasmus, Bolbocerosoma and Eucanthus is the first evidence for a close relationship among genera, but more characters should be analysed to test the support for the clade. A preliminary classification at tribe level of Geotrupinae is suggested as follows: Chromogeotrupini (type genus Chromogeotrupes), Lethrini (type genus Lethrus), Taurocerastini (type genus Taurocerastes) and Geotrupini (type genus Geotrupes). Some ecological facts of Geotrupidae evolution could also be explained by the present results, such as those related to diet and nesting behaviour. Both coprophagy and male–female co‐operation in nesting appear as derived traits.     

ISOLATION OF DI(HYDROXYMETHYL)DIHYDROXYPYRROLIDINE FROM THE CYANOBACTERIAL GENUS CYLINDROSPERMUM THAT EFFECTIVELY INHIBITS DIGESTIVE GLUCOSIDASES OF AQUATIC INSECTS AND CRUSTACEAN GRAZERS1

An effective glucosidase inhibitor was isolated from the cyanobacterial genus Cylindrospermum. Its chemical structure was determined by MS and NMR spectrometry to be di(hydroxymethyl)dihydroxypyrrolidine (DMDP; 2(R),5(R)‐bis‐(hydroxymethyl)‐3(R), 4(R)‐dihydroxypyrrolidine). Its identity was established by comparison with an authentic compound. All five species of Cylindrospermum investigated synthesized this compound but accumulated it to a different extent intracellularly. Particularly active producers were the axenic C. licheniforme (22 pmol·nmol chl a ^{? 1} 1 Received 5 March 2002. Accepted 2 October 2002. ) and a monoxenic unknown species of Cylindrospermum that contained the maximum amount (159 pmol·nmol chl a ^{? 1} 1 Received 5 March 2002. Accepted 2 October 2002. ). The major part of DMDP was found to be extracellular for all species investigated. The isolated compound inhibited digestive α‐ and β‐glucosidases isolated from crustacean zooplankton (IC₅₀ 19 and 49 nM, respectively). The bacterial 1‐deoxynojirimycin, which was used as a well‐studied reference glucosidase inhibitor, was less inhibitory (IC₅₀ 520 and 2190, respectively). Digestive enzymes of macrozoobenthos (chironomids, trichoptera, and ephemeroptera) were less sensitive to DMDP. The insect digestive β‐glucosidase was more effectively inhibited than the α‐glucosidase. Beside others, the ecological function of the glucosidase inhibitor may be the reduction of the digestibility of the cyanobacterium for grazers.     

CHARACTERIZATION OF THE LIGHT-HARVESTING COMPLEX OF GIRAUDYOPSIS STELLIFER (CHRYSOPHYCEAE) AND EFFECTS OF LIGHT STRESS1

The light-harvesting complex (LHC) of Giraudyopsis stellifer Dangeard was isolated on a sucrose density gradient after digitonin treatment, and the pigment composition was analyzed by reverse-phase high-pressure liquid chromatography. The LHC is a chlorophyll (Chl) a/c/ fucoxanthin/violaxanthin complex, depleted of β-carotene, comparable to the LHC of Fucophyceae. The excitation transfer from Chl c and fucoxanthin to Chl a is efficient in whole cells. Immunological reactions indicate a close relationship between Chrysophyceae and Fucophyceae. The immunocytochemical labeling confirms the lack of segregation of the LHC in the appressed membranes of the three associated thylakoids and its localization in the intrapyrenoid thylakoid. The violaxanthin-antheraxanthin-zeaxanthin cycle is operative in the cells and efficiently protects photosystem II reaction centers against photoinhibition.     

DETECTION OF CHLOROPHYLL C1 AND MAGNESIUM-2,4-DIVINYLPHEOPORPHYRIN A5 MONOMETHYLESTER IN CRYPTOPHYTES1

Three different chlorophyll (chl) c-type pigments were isolated from two cryptophyte species by silica thin-layer chromatography or polyethylene high-performance liquid chromatography. Chroomonas sp. Hansgirg contained chl c₁ and magnesium-2,4-divinylpheoporphyrin a, mono-methylester; chl c₂ and magnesium-2,4-divinylpheoporphyrin a₅ monomethylester were found in Cryptomonas maculata (syn. Rhodomonas maculata Butcher). These identifications were based on spectral characteristics and on comparison with reference pigments isolated from the synurophycean Synura petersenii Korshikov and the prasinophyte Mantoniella squamata Manton & Park. Neither of the cryptophyte species contained chl c₁ and chl c₂. The significance of chl c₁ as a major pigment and the occurrence of magnesium-2,4-divinylpheoporphyrin a₅ monomethylester in cryptophytes are discussed.     

USE OF NATIVE PLANTS FOR REMEDIATION OF TRICHLOROETHYLENE: II. CONIFEROUS TREES

The phytoremediation of trichloroethylene (TCE) from contaminated groundwater has been extensively studied using the hybrid poplar tree (Populus spp.). Several metabolites of TCE have been identified in the tissue of poplar including trichloroethanol (TCEOH) and dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA). In addition to the use of hybrid poplar for the phytoremediation of TCE, it is important to screen native tree species that could be successful candidates for field use. This study involves a greenhouse-based comparison of four different native southeastern conifers to a hybrid poplar species for their potential to phytoremediate TCE through the analysis of various plant tissues for TCE and major TCE metabolites, as well as several growth parameters that are desirable for phytoremediation. Longleaf pine (Pinus palustris), Leyland cypress (X Cupressocyparis leylandii), two varieties of Loblolly pine (Pinus taeda), and hybrid poplar species H11-11 (Populus trichocarpa x deltoides) were examined for the concentration of TCE and its metabolites in their tissue following treatment with either a low (50 mg L^?1) or high dose of TCE (150 mg L^?1) for 2 mo. The amount of water taken up, change in height of the tree, TCE transpiration, and total fresh weight of various tissue types were also measured. All trees contained detectable levels of TCE in their root and stem tissue. TCEOH was found only in the tissue of longleaf pine, suggesting that TCE metabolism was occurring in this tree. TCAA was only detected in the leaves of hybrid poplar and piedmont loblolly pine. Conifers took up less water over the 2-mo treatment period than hybrid poplar and grew at a slower rate. However, phytoremediation field sites may benefit from the evergreen's ability to transpire water throughout the winter months.     

THE GENETIC ARCHITECTURE OF GROWTH RATE IN JUVENILE TAKIFUGU SPECIES

Closely related species have often evolved dramatic differences in body size. Takifugu rubripes (fugu) is a large marine pufferfish whose genome has been sequenced, whereas T. niphobles is the smallest species among Takifugu. We show that, unsurprisingly, the juvenile growth rate of T. rubripes is higher than that of T. niphobles in a laboratory setting. We produced F₂ progenies of their F₁ hybrids and found one quantitative trait locus (QTL) significantly associated with variation in juvenile body size. This QTL region (3.5 Mb) contains no known genes directly related to growth phenotype (such as IGFs) except Fgf21, which inhibits growth hormone signaling in mouse. The QTL in Takifugu spp. is distinct from the region previously known to control body size variations in stickleback or tilapia. Our results suggest that in the fish tested herein, genomic regions underlying body size evolution might have different genetic origins. They also suggest that many diverse traits in Takifugu spp. are amenable to genetic mapping.