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。     

黄斑长翅卷蛾触角感觉器的扫描电镜研究

对黄斑长翅卷蛾成虫触角感觉器在相差显微镜和扫描电镜下作了观察，触角由柄节，梗工节和４６￣４８个鞭节组成，触角背面被鳞片覆盖，绝大多数触角感器位于触角的腹面和侧面，在雌、雄蛾的触角上可观察到以下７种感器，即毛形感器，刺形感器，腔锥感器，椎锥感器，鳞形感器，耳形感器、Ｂｏｈｍ氏鬃毛，触角感觉器的数量，分布，密度在雌，雄成虫上具有明显的差异。     

云南木蠹象触角感器的扫描电镜观察

利用扫描电镜对云南木蠹象雌雄成虫触角上的感器进行观察和研究.结果表明:云南木蠹象成虫触角膝状,由柄节、梗节和鞭节组成,其中鞭节由7个亚节组成.在雌、雄成虫触角上均存在6种感器,即毛形感器、锥形感器、脚形感器、芽形感器、端指形感器和腔形感器,其中毛形感器和端指形感器的数量较多;此外,雌成虫触角还有双芽形感器,雄成虫触角上还有耳形感器.与端指形感器、脚形感器、双芽形感器结构相同的感器在鞘翅目已有的研究资料中还未见报道.是新发现的昆虫触角感器.对云南木蠹象触角不同种类感器的形态、分布以及雌雄间触角感器的分布和数量差异进行描述.     

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。     

杜鹃冠网蝽触角感器的扫描电镜观察

利用电子扫描显微镜,对杜鹃冠网蝽成虫触角感器进行观察,从而了解杜鹃冠网蝽触角感器的分布、种类和形态特征。结果显示:杜鹃冠网蝽成虫触角为丝状,分为柄节、梗节和鞭节。成虫触角上存在着5种化学感器,即毛形感器、刺形感器、锥形感器、腔形感器和Bhm氏鬃毛。雌雄个体之间触角感受器种类相同,不同类型的感器在触角各节上的数量与分布各不相同,其中,毛形感器数量最多、分布最广。同时对杜鹃冠网蝽触角与其相近种昆虫触角间的差异进行了比较,以期为杜鹃冠网蝽的行为学、形态学和电生理学等方面的研究提供基础资料。     

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.     

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。     

桐花树毛颚小卷蛾防治试验

采用战螟、灭幼脲、三令、16 000 IU/mg Bt、锌硫磷5种药剂对桐花树毛颚小卷蛾幼虫进行野外防治试验,利用黑光灯进行了野外诱集成虫试验,并对该害虫的寄生性天敌进行了研究。试验结果表明:三令和锌硫磷对桐花树毛颚小卷蛾幼虫的野外防治效果最好,其次是战螟和灭幼脲,Bt的防治效果最差;同时,黑光灯对桐花树毛颚小卷蛾成虫具有很好的引诱效果,寄生性天敌也对桐花树毛颚小卷蛾具有较好的控制作用。     

脐腹小蠹成虫触角结构与感受器扫描电镜观察

对脐腹小蠹雌、雄成虫触角进行扫描电镜观察,结果表明:脐腹小蠹雌雄成虫之间触角形态及感器分布没有显著差异.触角锤头部感受器数量最多,约占全部感器数量的98.4%.触角上的感受器类型可以分为4种:锯齿形感受器、芽形感受器、锥形感受器、刺形感受器,分别约占全部感器数量的57.7%,28.6%,12.6%和1.1%.锯齿形感受器在触角各部均有分布,其中,锤头部的约占全部锯齿状感受器总数量的99.2%,柄节和鞭节数量只占0.8%;芽形感受器被埋于触角锤头部锯齿形感受器下面或者分散于锤头部端部;锥形感受器散生在锤头部端部边缘,与芽形感受器混生;刺形感受器分布于柄节和鞭节的连接处.     

Browsing Damage on Pine (Pinus sylvestris and P. contorta) by a migrating moose (Alces alces) Population in Winter: Relation to Habitat Composition and Road Barriers

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.     

Effects of Root Freezing on the Physiology and Growth of Picea glauca,Picea mariana and Pinus banksiana Seedlings Under Different Soil Moisture Regimes

The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage.     

Stand Structure in Pine,Spruce and Deciduous Forests: A Comparison Between Finnish and Russian Karelia

This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland.     

Growth and Terminal Bud Formation in Picea abies Seedlings Grown with Alternating Diurnal Temperature and Different Light Qualities

The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions.     

CAD与建筑设计的关系

本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。     

Natural Regeneration in Clear-cuts: Effects of Scarification,Slash Removal and Clear-cut Age

The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided.     

Risk Perception Among Non-industrial Private Forest Owners

Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken.     

Interactions in decomposition and N mineralization between tropical legume residue components

In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts (stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea (Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea, largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols. Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its components are mixed.     

Pasture production and tree growth in a young pine plantation fertilized with inorganic fertilizers and milk sewage in northwestern Spain

The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization, (2) milk sewage sludge at 40 kg N ha⁻¹ target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha⁻¹. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹); (2) Lolium perenne L. var. Tove (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea (Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m², with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral systems. This revised version was published online in June 2006 with corrections to the Cover Date.