紫胶蚧觅食时对寄主植物枝条的选择

研究了紫胶蚧觅食行为特点和紫胶蚧觅食时对寄主植物枝条的选择行为。结果表明：紫胶蚧觅食时有向前、向上寻找的特性,觅食初期前进路线的选择也采取ESS对策。紫胶蚧选择在1年生及其以下枝条上固定取食的比率达95％以上,1年生以上2年生以下枝条上固定取食的比率为5％,基本不在2年生及其以上枝条上固定取食。紫胶蚧分布与不同方向枝条之间无关。紫胶蚧取食久树枝条的枝径范围在0．47～1．60cm之间,枝径在0．6～1．1cm之间的占88%。在直立枝条上,紫胶蚧呈环状带分布,在多数倾斜枝条上,紫胶蚧分布在背阴面。比较解剖结果发现,久树2年生枝条背阴面的周皮、皮层明显比1年生枝条的增厚;石细胞和纤维细胞在皮层中分布数量多,连成带状,比久树1年生枝条中石细胞和纤维细胞组成的带状物要厚27μm;从周皮到韧皮部筛管的距离,久树2年生枝条的比1年生枝条要厚,枝条上端树皮的周皮、皮层比枝条基部树皮的要薄。枝条向阳面韧皮部厚度要比背阴面薄。     

Flight pattern of some Scolytidae attracted to flight barrier traps baited with ethanol in an oak forest in Greece

In an oak forest (Quercus frainetto) flight barrier traps baited with ethanol were used in order to attract wood and bark boring insects and study their flight pattern. There were trapped 19 species from which 9 were Scolytidae, 3 Bostrychidae, 2 Anobiidae, 1 Platypodidae and 1 Buprestidae. The most frequently species trapped was Xyleborus saxeseni. Totally 5 scolytid species (X. saxeseni, X. dispar, X. monographus, X. dryographus and Trypodendron signatum) were trapped in relatively high numbers. Their flight pattern is presented and discussed.     

Foraging ability and growth performance of four subtropical tree species in response to heterogeneous nutrient environments

Considering the ubiquitous heterogeneity in spatial distribution of soil nutrients, we conducted a pot experiment to investigate the foraging traits and growth performance of four important subtropical tree species in a heterogeneous nutrient environment. The tested species exhibited large differences in foraging traits as well as growth benefits obtained from root foraging. Pinus massoniana, Schima superba and Liriodendron chinese all showed a higher degree of root morphological plasticity (expressed as relative fine root mass difference; RFRMD) than Cunninghami lanceolata (P < 0.05). P. massoniana exhibited the largest degree of morphological plasticity, followed by L. chinese and S. superba, whereas there were no significant differences in RFRMD among the three species. S. superba was the only species that exhibiting both morphological plasticity and physiological plasticity. Both P. massoniana and S. superba exhibited greater whole-seedling biomass and high sensitivity in response to nutrient heterogeneity, resulting from both types of plasticity. In contrast, both types of root plasticity were poor for C. lanceolata, resulting in poor growth benefit in heterogeneous environments. As for L. chinese, the root proliferation in nutrient-rich patches occurred at the expense of depressed root growth in other parts of the root system, leading to the lack of increment in total root biomass and nutrient absorption in heterogeneous environments. Our results provide insight and practical advice for silviculture and forest management.     

Forest insect assemblages attracted to light trap on two high mountains(Mt. Jirisan and Mt. Hallasan) in South Korea

Assemblages of forest insects across two high mountains(Mt.Hallasan:JJ and Mt.Jirisan:JR) in South Korea were compared by collecting insects using an ultraviolet light trap at 20 sites(200–1700 m elevation ranges) from May to October 2013.A total of 2960 individuals,representing 481 species of 10 orders,were collected on JJ,compared with 7080 individuals representing769 species of 14 orders on JR.The estimated number of species on JJ was 667 compared with 952 on JR.The differentiation among habitats(b-diversity) was higher on JJ(4.95) than JR(4.33) because of the island characteristics of JJ.Six insect orders(Lepidoptera,Coleoptera,Diptera,Hymenoptera,Hemiptera and Trichoptera) were dominant on both mountains,suggesting that the light trap captures represented well the insect fauna and is an effective method for investigating forest insect diversity.We concluded that forest insect assemblages on mountains are mainly affected by the elevation and the dominant forest in each elevation.In addition,the insect fauna on each mountain was differentiated by the habitat,which could be correlated with geological history.     

Natural decline of volatile acids due to aging of living trees

Wood age, i.e., number of years that have passed after the annual rings of xylem tissue developed from cambium, had a strong negative impact on the volatile acid content of wood of the two oak species, Quercus petraea and Q. frainetto. Up to 80% of acetyl groups were cleaved off in the heartwood zones close to the pith if the living oak trees were about 200 years old.     

对桉树枝瘿姬小蜂不同抗性的3个桉树品种枝叶挥发物分析

为了探明不同抗感桉树枝瘿姬小蜂桉树品种(系)挥发物化学成分及其含量的差异,运用气相色谱-质谱联用技术(GC-MS)对不同抗性的3个桉树品种(系)的枝叶进行化学成分分析。分别从高感虫品种201-2、高抗虫品种广1和稍感虫品种雷11的嫩叶中检测到20,22和25种化学成分,其中相对含量超过0.5%的主要化学成分分别有9,8和13种,分别占挥发物总量的82.36%,60.31%和60.79%;3个桉树种挥发物含有8种共同成分;201-2、广1和雷11特有成分分别有12,7和12种,分别占总含量的14.24%,2.1%和13.29%。结果表明,对桉树枝瘿姬小蜂不同抗性的3个桉树品种挥发物具有较大差别。     

我们最贴近的园林——人居园林

诗意居住,多少年来一直是中国人追求的梦想,即便是处于21世纪的今天,无论生活节奏如何的快,无论生活中的琐事如何繁杂,人们对诗意般的住宅环境的追求始终未变,甚至更深。     

Behavioral responses of Callosobruchus maculatus to volatile organic compounds found in the headspace of dried green pea seeds

There is growing evidence that insects rely on chemical cues to locate food, hosts, predators, and potential mates. The pulse beetle Callosobruchus maculatus has been recognized for decades as the major post-harvest insect pest of legume seeds. In a previous study, we identified five volatile organic compounds in the headspace of dried green pea seeds as electroantennographically active in C. maculatus antennae: 1-pentanol, 1-octen-3-ol, (E)-2-octenal, nonanal, and 3-carene. Some of these compounds used individually elicited attraction toward C. maculatus adults. However, since volatile compounds are generally perceived by insects as blends, we hypothesized that C. maculatus might particularly show attraction to different mixtures of the aforementioned compounds. To test this, we examined the behavioral response of C. maculatus toward a quinary, a quaternary, two ternary, and three binary mixtures in a dual choice Y-tube olfactometer. The results seem to indicate that in a dual choice situation, the first choice made by the beetles is an indication of the attractive or repellent properties of the mixture tested. In most cases, a positive response of C. maculatus to the mixtures of volatiles was observed. Females were attracted to five mixtures, while males were attracted only to two binary mixtures consisting exclusively of aldehydes. The other mixtures caused C. maculatus to respond negatively, suggesting they were repellent. Further investigations with the attractive mixtures should be done in real storage conditions with the aim of developing a trap for the pulse beetle, C. maculatus.     

德国林业公共财政支持保护政策值得借鉴

德国是林业发达国家,森林资源十分丰富.德国的森林以私人经营保护为主,私有林面积占全部森林面积的46%,20%为社团和企业等所有,国有林(联邦和州有林)仅占34%.全国私有林主有130万人,占全国人口的1.6%,是从事农业生产人数的两倍多,人均经营林地3.8公顷.     

Mountain pine beetle-associated blue-stain fungi are differentially adapted to boreal temperatures

Mountain pine beetles (MPB) are the most serious pest of lodgepole pine in Canada and are likely to invade boreal jack pine forests. MPB vector three blue-stain fungi, Grosmannia clavigera, Ophiostoma montium and Leptographium longiclavatum, which contribute to beetle success. Fungal survival at extreme boreal temperatures will contribute to their success in jack pine. Growth, sporulation and survival of the three fungi at −20 to 37°C were tested in vitro. Overwintering survival of G. clavigera and O. montium was assessed in vivo. All species grew at 5–30°C, with optimal growth at 20–25°C. Grosmannia clavigera and L. longiclavatum survived at −20°C, but O. montium died. Growth of G. clavigera and L. longiclavatum was inhibited at 30°C, but O. montium grew well. Grosmannia clavigera and O. montium overwintered in living pines. These results suggest that G. clavigera and L. longiclavatum were adapted to cold boreal winters but not hot summers, with the converse true for O. montium. Temperature tolerance varied among G. clavigera isolates. British Columbian and Californian isolates grew faster at 25°C than Albertan isolates. Isolates from Alberta and Idaho/Montana grew optimally at 20°C, while British Columbian and Californian isolates grew optimally at 25°C.     

建设生态文明 共创绿色财富——德国林业公共财政支持保护政策值得借鉴

德国是林业发达国家,森林资源十分丰富。德国的森林以私人经营保护为主,私有林面积占全部森林面积的46%,20%为社团和企业等所有,国有林(联邦和州有林)仅占34%。全国私有林主有130万人,占全国人口的1.6%,是从事农业生产人数的两倍多,人均经营林地3.8公顷。德国林业的     

Behavioral responses of predaceous minute pirate bugs to tridecane,a volatile emitted by the brown marmorated stink bug

Since its introduction from Asia, the brown marmorated stink bug, Halyomorpha halys (Stål), has become a pest of many agricultural crops in the USA. Insect predators utilize H. halys as prey; however, the chemical cues used by them in prey location are largely unknown. Here, we hypothesized that tridecane, an H. halys-associated volatile, acts as a kairomone for the predaceous minute pirate bug, Orius insidiosus (Say). We conducted laboratory, greenhouse, and field experiments to: (1) assess the attraction of adult O. insidiosus to H. halys-damaged bean pods and tridecane in cage studies, and its effect on egg predation; (2) video record the behavioral response of O. insidiosus males and females to tridecane in a four-arm olfactometer; and (3) test whether Orius spp. are attracted to tridecane-baited sticky traps in peach, blueberry, and sunflower fields, and its effect on egg predation. In the greenhouse, O. insidiosus was attracted to H. halys-damaged pods and artificial plants baited with tridecane in the presence of prey (sentinel eggs); however, this attraction rarely led to increased egg predation. Although both O. insidiosus males and females spent more time in the arm of the olfactometer with tridecane, males were more responsive at a lower concentration than females. Similarly, Orius spp. were more attracted to tridecane-baited than unbaited traps in the field; however, there was no effect on egg predation. Altogether, while O. insidiosus is attracted to tridecane, this attraction did not always lead to higher predation, suggesting that this kairomone likely acts as an arrestant.     

Initial Responses to Fertilizing Eucalyptus grandis at Planting are Sustained until Harvesting

The results of six fertilizer experiments with Eucalyptus grandis are discussed and the development of various tree parameters with age are studied. It is shown that in the initial years of growth mean height and breast height diameter are increased as a result of fertilizing at the time of planting, but the absolute differences between fertilized and unfertilized trees remain more or less constant with increasing age. Fertilizing increases total basal area also, and consequently timber yield, but this increase becomes greater up to at least nine years of age or final felling. These increases in timber yield economically justify fertilizing at planting. Brief recommendations are given of how best to conduct field experiments designed to study fertilizer application.     

生态产业两手抓实现林业健康发展

林业要实现真正的跨越式发展,必须实行生态建设与产业发展两手抓。省直林区在全省林业生态建设与产业发展中具有特殊重要地位,应积极培育稳定的森林生态系统,重视林业科技,发展后续产业,调整林区产业结构。     

英国买家在签订新合同的问题上态度消极

2010年第1季度供应问题加剧12月初,英国进口商和木材批发商在斯堪的纳维亚半岛和欧洲东北部地区的针叶锯材交付合同签订数量很少。这主要是由于英国锯材需求量较低和锯材供应量较少。到目前为止,为了保证春季原材料供应量充足,     

Vessel size and number are contributors to define wood density in cork oak

Cork oak (Quercus suber L.) has a dense wood that allows high-quality uses. In the present work, we study the influence of vessel characteristics, measured through image analysis and optical microscopy, on wood density, measured using X-ray microdensitometry, on 40-year-old trees. Vessel area increases with cambial age (5403–33064 μm²), while wood density decreases (1.229–0.836 g/cm³). The number of vessels is relatively constant at 6 vessels/mm², while vessel proportion in cross-section increases from 3.3% near the pith to 20.5% near the bark. In growth rings closest to the pith, with high wood density and low vessel area, the relationship between the two variables is linear (R ² = −32.1%, P < 0.01) but with increasing tree age and vessel size, the wood density remains rather constant, suggesting that decreases in density might compromise mechanical support of the tree at a stage when the increase in cross-sectional area alone might not provide mechanical stability. Other anatomical characteristics not considered in this study, like large xylem rays that increase with cambial age, may be responsible for the constant density.     

Chemical compounds released from five different woods used to make barrels for aging wines and spirits: volatile compounds and polyphenols

Aging wine and spirits in wooden barrels is an industrial process used to stabilize color and improve limpidity; many compounds are released from the wood and enrich the sensorial characteristics of the product. The main wood species used for making barrels is oak, but in particular cases also acacia, chestnut, cherry and mulberry. In this work, polyphenols contained in the extracts of these wood species obtained by solutions of 50% hydroalcohol as well as a model wine were studied and compared with the extracts from oak. The hydroalcoholic extracts of chestnut and mulberry had higher total polyphenols, followed by cherry, acacia and oak, respectively. The oak model wine extract had the highest percentage of polyphenols extractable by the wine, followed by chestnut, acacia, cherry and mulberry, respectively. Chestnut extracts had the highest percentage of oxidizable compounds, followed by acacia, oak, mulberry and cherry. The GC/MS–EI profile of 50% hydroalcoholic extracts revealed as principal volatiles several benzene compounds containing a guaiacol residue, and high contents of C₆–C₁₈ fatty acids. To our knowledge, this is the first study reporting on polyphenolic and complete volatile compounds characterization of these woods for oenological purposes.