笋秀夜蛾触角感器的扫描电镜观察

应用扫描电镜观察笋秀夜蛾触角的外部形态.雌蛾触角具8种感器,雄蛾触角具9种感器,其中毛形感器数量最多,其次是腔锥形感器和耳形感器,除毛形感器外,其他感器的数量和着生部位较为恒定.毛形感器、锥形感器、刺形感器、耳形感器、腔锥形感器、栓锥形感器Ⅰ型、鳞形感器和B(o)hm氏感器等为雌雄触角所共有,无缘腔锥感器、双缘腔锥形感器、腔乳头感器仅雄蛾触角具有;栓锥形感器Ⅱ型仅生于雌蛾触角.触角雌雄性二型现象明显,除了感器种类、形态和表面细微结构的差异外,雌蛾触角的鞭节存在融合征状,雄蛾触角却无此现象.     

竹织叶野螟触角感器的超微形态特征

应用扫描电镜技术对竹织叶野螟雌雄蛾触角感器进行研究。结果表明,竹织叶野螟触角呈丝状,由柄节、梗节和分为74~80个亚节的鞭节组成。触角上存在7种感器,其中毛形感器数量最多,其次是耳形感器和腔锥形感器;毛形感器、刺形感器、腔锥形感器Ⅰ型、耳形感器Ⅰ型、栓锥形感器、鳞形感器和Bhm氏感器为雌雄蛾所共有,腔锥形感器Ⅱ型、耳形感器Ⅱ型仅分布于雄蛾触角上,且腔锥形感器Ⅱ型为螟蛾科首次发现。对竹织叶野螟触角各感器的形态、分布以及雌雄间触角感器形态和数量差异进行描述,此外就竹织叶野螟与其相近种昆虫触角感器间的差异进行讨论。     

杨背麦蛾(鳞翅目:麦蛾科)触角感器的超微结构

【目的】了解杨背麦蛾成虫触角感器的类型、数量、分布和超微形态。【方法】利用扫描电镜技术观察杨背麦蛾雌、雄蛾的触角感器。【结果】杨背麦蛾触角感器绝大部分位于触角鞭节的腹面和侧面,少部分位于柄节和梗节。基于感器外部形态可分为8种类型:Bhm氏鬃毛(BBⅠ型和BBⅡ2种亚型)、毛形感器、锥形感器(SBⅠ和SBⅡ2种亚型)、刺形感器、腔锥形感器、耳形感器、鳞形感器和栓锥形感器。其中毛形、锥形和耳形感器表皮具多孔,属于嗅觉感器。雌、雄蛾触角感器形态和分布无明显差异。但雄蛾触角与雌蛾相比,亚鞭节多1~4节;毛形和锥形SBⅡ感器明显长于雌蛾;刺形和腔锥形感器基部直径雄蛾明显长于雌蛾;毛形、锥形、刺形、腔锥形和鳞形感器总数均明显多于雌蛾。【结论】杨背麦蛾触角感器种类丰富,多数具有嗅觉功能,雌、雄蛾触角感器在数量和特征上有明显的性二型现象。     

核桃举肢蛾成虫触角的超微结构观察

【目的】研究核桃果实害虫核桃举肢蛾的触角超微结构特征,为进一步利用触角代学通信系统开发新的防治技术提供参考。【方法】利用扫描电镜对核桃举肢蛾雌雄成虫触角、感受器及其鳞片细微结构分别进行观察。【结果】核桃举肢蛾触角为丝状,由柄节、梗节和鞭节组成,雌雄成虫鞭节分别由45和51个亚节组成。雌雄成虫触角上存在9种感器,即毛形感器、刺形感器、耳形感器、腔锥形感器、栓锥形感器、鳞形感器、B9hm氏鬃毛、锥形感器和钟形感器。其中毛形感器、耳形感器和腔锥形感器各有2种类型,即长曲毛形感器和长直毛形感器、Ⅰ型耳形感器和Ⅱ型耳形感器、具缘毛腔锥形感器和无缘毛腔锥形感器。不同类型的感器在触角各亚节上的分布与数量各不相同,感器主要着生于触角腹面,长曲毛形感器和钟形感器仅存在于雄虫触角上。雌雄成虫的B9hm氏鬃毛分布于触角基部,且形态上存在较大差异。触角柄节、梗节表面布满鳞片,鞭节除末端一节无鳞片外,各亚节背面和侧面均覆盖有鳞片,腹面无鳞片。鳞片上分布有小孔、纵肋、横梁和小梁等细微结构。雌虫各亚节鳞片上的纵脊间距、纵脊宽度、横梁长度和小梁长度均大于雄虫。小孔主要分布于触角柄节、梗节及鞭节基本的部分亚节上,小孔类型可分为单孔、双孔、三孔、四孔、五孔、六孔和七孔。不同部位鳞片上小孔的类型和分布存在差异,雌虫触角柄节鳞片上小孔类型比雄虫丰富,雄虫触角梗节和鞭节鳞片上小孔类型比雌虫丰富。【结论】本研究可明晰核桃举肢蛾触角感器类型及鳞片上小孔等超微结构特征,其具体功能还需结合电生理学、形态学、分子生物学进一步研究。     

云斑天牛头部附器感器的扫描电镜观察

利用扫描电镜观测云斑天牛成虫触角、下颚须和下唇须的感器类型、形态及分布特征,并分析比较雌雄之间存在的差异。结果表明:云斑天牛触角上共存在5类感器,即毛形感器、锥形感器、刺形感器、凹槽钉形感器、乳突形感器,其中锥形感器分5种亚型,刺形感器分2种亚型。云斑天牛雌、雄成虫触角存在性二型现象:1)虽然雄虫体型明显小于雌虫,但雄虫触角却显著长于雌虫触角;2)乳突形感器只在雌虫触角上发现,且雌虫触角上的粗长锥形感器(BⅠ)、粗短锥形感器(BⅡ)和长刺形感器(ChⅡ)在数量上多于雄虫,但发锥形感器(BⅢ)少于雄虫;3)雌虫触角上的刺形感器(包括ChⅠ和ChⅡ)的长度显著长于雄虫。其他感器的形态及数量在两性触角间均不存在显著差异。在下颚须和下唇须上都发现了毛形感器、长刺形感器、末梢锥形感器(包括TBⅠ和TBⅡ2个亚型)、钟形感器和隙缝感器5类。下颚须和下唇须的长度在两性之间无明显差异,但下颚须的末梢锥形感器数量多于下唇须,隙缝感器少于下唇须;雌虫的末梢锥形感器数量多于雄虫,钟形感器少于雄虫。     

黄野螟成虫触角电镜观察及其对7种杀虫剂的EAG反应

黄野螟(Heortia vitessoides)是土沉香(Aquilaria sinensis)的重要食叶害虫。本文利用扫描电镜技术对黄野螟雌、雄成虫触角进行观察,利用触角电位技术分析触角对7种杀虫剂的电位反应。结果表明:黄野螟成虫触角长8600~9100μm,雌雄触角均为线状,感受器主要有毛形感器、鳞形感器、腔锥感器、刺形感器、耳形感器和栓锥形感器6种。其中毛形感器分布最广、数量最多。黄野螟雄虫的毛形感器在数量上多于雌虫。在触角电位检测中,雌雄黄野螟成虫存在差异,黄野螟雄成虫对乙多·甲氧虫酰肼的反应相对平均值最大;黄野螟雌成虫对苏云金杆菌的反应相对平均值最大。     

川硬皮肿腿蜂雌蜂触角超微结构观察

应用扫描电镜对川硬皮肿腿蜂两种类型雌蜂触角的外部形态结构进行了观察,结果表明:川硬皮肿腿蜂雌蜂触角上有18种感器,其中有毛形感器Ⅰ型、Ⅱ型,刺形感器Ⅰ型,锥形感器Ⅰ型,鳞形感器,栓锥形感器Ⅰ型、Ⅱ型,钟形感器,坛形感器,板形感器,柱形感器Ⅰ型、Ⅱ型,长锥形感器和边缘感器为两种类型共有,仅数量和分布存在差异;毛形感器Ⅳ型、锥形感器Ⅱ型只在有翅雌蜂触角上存在;毛形感器Ⅲ型、刺形感器Ⅱ型只在无翅雌蜂中存在。     

柑橘长卷蛾触角感器种类与分布的形态学研究

应用电子扫描显微镜对柑橘长卷蛾雌雄成虫触角上的化学感受器进行了观察和研究,发现成虫触角上存在着6种感器,即毛形感器、刺形感器、锥形感器、腔锥形感器、耳形感器,柱形感器,其中以毛形感器和耳形感器数目最多。柑橘长卷蛾雌雄成虫触角感器的种类、分布和形态特征也存在一定差异。柑橘长卷蛾触角感器种类较多,分布具有一定的规律性。研究柑橘长卷蛾触角感器的种类、数量和分布等特征,可为解释其生态学习性和对其进行电生理学等方面的研究提供依据。     

竹斑蛾触角感器电镜扫描观察

利用扫描电镜对竹斑蛾雌、雄成虫触角感觉器的类型、分布进行了观察。结果发现:竹斑蛾成虫触角上有5种感器,分别是刺形感器,毛形感器,芽形感器,栓锥形感器,腔锥形感器;绝大部分触角感觉器位于触角的腹面和侧面.雌雄蛾触角上的感器种类大体相同,但也存在差异;雄蛾触角上没有发现芽形感器;另外,毛形感器的长度、数量在两性之间也存在差异。     

库尔勒香梨优斑螟触角感受器超微结构观察

为研究香梨优斑螟触角感器的种类、分布和形态特征,利用电子扫描显微镜,对香梨优斑螟成虫触角感器进行观察。结果表明:成虫触角上存在着6种化学感器,即毛形感器、刺形感器、柱形感器、耳形感器、腔锥形感器和鳞形感器,其中,毛形感器数目最多,柱形感器雄虫特有,柄节和梗节上没有发现感器。研究香梨优斑螟触角感器为其形态学、行为学和电生理学等方面的研究提供基础资料,同时对香梨优斑螟触角与其相近种昆虫触角间的差异及部分感器可能具有的生理功能进行了分析。     

Antimicrobial activity of some endemic plants growing in the Eastern Black Sea Region, Turkey

The Eastern Black Sea Region has an extensive flora because of ample rainfall lasting all year. In this study, antimicrobial effects of 74 crude extracts of 22 endemic plants were investigated. Among the 30 active crude extracts, water-insoluble crude extracts from Betula medwediewii, Heracleum platytaenium, Primula longipes, Anthemis cretica ssp. argaea and Centaurea helenioides were the prominent ones with their MIC values.     

Antibacterial activity of plant extracts from Brazilian southeast region

A screening was conducted with 26 plants collected in the Brazilian southeast region, to identify plant extracts with antibacterial properties against Aeromonas hydrophila, Bacillus subtilis, Pseudomonas aeruginosa and Staphylococcus aureus. Initially, the agar diffusion method was employed. Then, those extracts presenting activity were submitted to a broth microdilution assay to determine the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). It was observed that 13 of the tested extracts showed antibacterial activity. The best results were obtained with those from Lantana lilacina and Phyllanthus tenellus.     

Growth and physiological response of six Australian rainforest tree species to a light gradient

An understanding of growth and photosynthetic potential of subtropical rainforest species to variations in light environment can be useful for determining the sequence of species introductions in rainforest restoration projects and mixed species plantations. We examined the growth and physiology of six Australian subtropical rainforest tree species in a greenhouse consisting of three artificial light environments (10%, 30%, and 60% full sunlight). Morphological responses followed the typical sun-shade dichotomy, with early and late secondary species (Elaeocarpus grandis, Flindersia brayleyana, Flindersia schottiana, and Gmelina leichhardtii) displaying higher relative growth rate (RGR) compared to mature stage species (Cryptocarya erythroxylon and Heritiera trifoliolatum). Growth and photosynthetic performance of most species reached a maximum in 30–60% full sunlight. Physiological responses provided limited evidence of a distinct dichotomy between early and late successional species. E. grandis and F. brayleyana, provided a clear representation of early successional species, with marked increase in A_max in high light and an ability to down regulate photosynthetic machinery in low light conditions. The remaining species (F. schottiana, G. leichhardtii, and H. trifoliolatum) were better represented as falling along a shade-tolerant continuum, with limited ability to adjust physiologically to an increase or decrease in light, maintaining similar A_max across all light environments. Results show that most species belong to a shade-tolerant constituency, with an ability to grow and persist across a wide range of light environments. The species offer a wide range of potential planting scenarios and silvicultural options, with ample potential to achieve rapid canopy closure and rainforest restoration goals.     

利用三种梢栖真菌生物防治落叶松枯梢病的研究

从落叶松梢栖真菌筛选出对落叶松枯梢病病原菌有抑制作用的菌株,对落叶松枯梢病进行生物防治。将自落叶松梢部分离到的11种梢栖真菌与落叶松枯梢病病原菌进行对峙培养,根据被覆盖程度、抑菌率、拮抗系数和防治预试验的结果,综合评价后发现:粪生粪壳、深绿木霉和球毛壳3种梢栖真菌对落叶松枯梢病有良好的拮抗作用。利用这3个菌株在黑龙江省勃利县通天一林场国富沟进行林间防治试验,结果表明:防治效果为粪生粪壳>代森锰锌400倍液>深绿木霉>球毛壳;深绿木霉和粪生粪壳喷洒浓度50%和球毛壳喷洒浓度75%时,真菌多样性最多,梢栖真菌系统较其他浓度更为稳定,与化学防治相比,既达到了防治目的又具有不污染环境的优势。     

Ungulate herbivory of regenerating conifers in relation to foliar nutrition and terpenoid production

Ungulate browsing greatly influences regeneration dynamics of some forest ecosystems, yet the relationship between browse susceptibility and foliar chemistry of forest tree seedlings is not well understood. We applied field fertilization (15N-9P-10K controlled-release fertilizer at 0, 20, 40, and 60 g per seedling) and investigated how subsequent changes in terpenoid production and foliar nutrition influence ungulate browse preference for Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco), western hemlock (Tsuga heterophylla Raf. Sarg.), and western redcedar (Thujaplicata Donn ex D. Don) seedlings across four sites in northwestern Oregon, USA. Fertilization increased foliar N concentration of all three species, but above-ground growth of only Douglas-fir and western hemlock. Foliar monoterpene concentrations for western hemlock and western redcedar also increased at higher fertilization rates, while Douglas-fir monoterpene production was not affected by fertilization. Regardless of monoterpene levels, ungulate browse preference was greater for fertilized western hemlock seedlings. The opposite response, however, was observed for western redcedar at two of the four study sites where the likelihood of browse was greater for non-fertilized than fertilized seedlings. Differences in browse preference among species may depend on the type and amount of individual monoterpenes manufactured in response to fertilization. Western redcedar produce α- and β-thujone, oxygenated monoterpenes known to promote gastroenteritis and possibly inhibit microbial rumen activity, which were absent from Douglas-fir or western hemlock. Higher concentrations of α- and β-thujone associated with increasing fertilizer rate provide a plausible explanation as to why ungulates preferred non-fertilized western redcedar. Our results illustrate species-specific adaptation in browse avoidance and selective ungulate browsing behavior of individual trees as linked to foliar chemistry.     

Effects of prescribed fire and season of burn on direct and indirect levels of tree mortality in Ponderosa and Jeffrey Pine Forests in California,USA

Many forests that historically experienced frequent low-intensity wildfires have undergone extensive alterations during the past century. Prescribed fire is now commonly used to restore these fire-adapted forest ecosystems. In this study, we examined the influence of prescribed burn season on levels of tree mortality attributed to prescribed fire effects (direct mortality) and bark beetles (Coleoptera: Curculionidae, Scolytinae) (indirect mortality) in ponderosa pine, Pinusponderosa Dougl. ex Laws., and Jeffrey pine, Pinusjeffreyi Grev. and Balf., forests in California, USA. A total of 816 trees (9.9% of all trees) died during this 3-yr study. Significantly higher levels of tree mortality (all sources) occurred following early and late season burns compared to the untreated control, but no significant difference was observed between burn treatments. The majority (461 trees) of tree deaths were attributed to direct mortality from prescribed burns and was strongly concentrated (391 trees) in the smallest diameter class (<20.2 cm diameter at breast height, dbh). For the largest trees (>50.7 cm dbh), significantly higher levels of tree mortality occurred on early season burns than the untreated control, most of which resulted from indirect mortality attributed to bark beetle attacks, specifically western pine beetle, Dendroctonus brevicomis LeConte, and mountain pine beetle, D. ponderosae Hopkins. Red turpentine beetle, D. valens LeConte, was the most common bark beetle species found colonizing trees, but tree mortality was not attributed to this species. A total of 355 trees (4.3% of all trees) were killed by bark beetles. Dendroctonus brevicomis (67 trees, 18.9%) and D. ponderosae (56 trees, 15.8%), were found colonizing P. ponderosa; and Jeffrey pine beetle, D. jeffreyi Hopkins, was found colonizing P. jeffreyi (seven trees, 2.0%). We also found pine engraver, Ips pini (Say) (137 trees, 38.6%), and, to a much lesser extent, Orthotomicus (=Ips) latidens (LeConte) (85 trees, 23.9%) and emarginate ips, I. emarginatus (LeConte) (3 trees, 0.8%) colonizing P. ponderosa and P. jeffreyi. Few meaningful differences in levels of indirect tree mortality attributed to bark beetle attack were observed between early and late season burns. The incidence of root and root collar pathogens (Leptographium and Sporothrix spp.), including species known to be vectored by bark beetles, was low (18% of trees sampled). The implications of these and other results to management of P. ponderosa and P. jeffreyi forests are discussed in detail.     

Anti-HBV activities of Streblus asper and constituents of its roots

The extracts from leaves, heartwood, barks and roots of the Streblus asper were investigated for anti-HBV activities, separately. The results suggested that the MeOH extracts of the heartwood, barks, and roots exhibited good anti-HBV activities. Further investigations displayed that ethyl acetate and n-butanol soluble parts of their MeOH extracts showed more significant anti-HBV activities. Moreover, a new lignan, together with 11 known compounds, was isolated from n-butanol-soluble part of MeOH extract of the roots of S. asper. The structures were elucidated by spectroscopic methods, including 1D NMR ((1)H NMR, (13)C NMR), 2D NMR (HMQC, HMBC) and HR-EI-MS experiments. Compounds 1-3 were evaluated for their anti-HBV activities. Honokiol showed significant anti-HBV activity with IC(50) values of 3.14μM and 4.74μM for HBsAg and HBeAg with no cytotoxicity respectively, while lamivudine (3TC, positive control) exhibited weak anti-HBV activity with IC(50) values of 11.81μM and 25.80μM for HBsAg and HBeAg respectively.     

Antimicrobial activity of the Derris elliptica, Derris indica and Derris trifoliata extractives

Various parts of Derris elliptica, Derris indica and Derris trifoliata on fractionation with a number of solvents (petrol, dichloromethane, ethyl acetate, butanol and methanol) gave fractions which demonstrated a varied level of broad spectrum antibacterial activity. Good activity was exhibited by the methanol fractions of the leaves and root heart-wood, petrol, butanol and methanol fractions of the root bark of D. indica and petrol and ethyl acetate fractions of D. trifoliata. None of the plants showed antifungal activity.     

Screening of antioxidant activity of three Euphorbia species from Turkey

Euphorbia acanthothamnos, E. macroclada and E. rigida were investigated for their antioxidant activity. The antioxidant potential of extracts of E. acanthothamnos, E. macroclada and E. rigida was evaluated using different complementary antioxidant tests.