四种旱生藓类植物的比较结构学观察

对新疆产的４种藓类植物茎、叶的表面及内部结构进行了观察,结果表明：尖叶大帽藓（Ｅｎｃａｌｙｐｔａ ｒｈａｂｄｏｃｕｒｐａ Ｓｃｈｗａｅｇｒ．）茎的中部结构类似于种子植物（单子叶）根的内皮层,其茎表皮也有类似于种子植物表皮毛（腺毛）的腺体。在阔叶紫萼藓（Ｇｒｉｍｍｉａ ｌａｅｖｉｇａｔａ（Ｂｒｉｄ．）Ｂｒｉｄ．）茎的中轴部,厚角组织发达,数层皮部厚壁组织也很发达。小石藓（Ｗｅｉｓｉａ ｃｏｎｔｒｏｖ     

Habitat quality favoured over familiarity: a rejection of natal habitat preference induction in the mosquito Aedes albopictus

1. Natal habitat preference induction (NHPI) is a behavioural phenomenon in which offspring show a change in preference in adult oviposition choice as a function of experience as an immature. 2. Although well known in certain systems, such as herbivorous insects, this behaviour has not been well studied in aquatic insects. 3. The container–breeding mosquito, Aedes albopictus (Skuse) was used to test if NHPI occurs in aquatic insects under natural conditions of two leaf species as a nutritive base (Juniperus virginiana L. and Quercus virginiana Mill) and two larval densities. 4. Significant effects of leaf species and density on adult mosquito attributes were found, with J. virginiana and low larval density associated with more, faster developing, larger and more fecund mosquitoes. However, no evidence for NHPI was found. Instead a canalised behavior was found that included spreading eggs between high– and low–quality oviposition choices in the same proportions regardless of larval experience.     

Effect of water deficit on the cell wall of the date palm (Phoenix dactylifera ‘Deglet nour’, Arecales) fruit during development

Date palm (Phoenix dactylifera) is an important crop providing a valuable nutrition source for people in many countries including the Middle East and North Africa. In recent years, the amount of rain in North Africa and especially in the Tunisian palm grove areas has dropped significantly. We investigated the growth and cell wall remodelling of fruits harvested at three key development stages from trees grown with or without water supply. During development, cell wall solubilization and remodelling was characterized by a decrease of the degree of methylesterification of pectin, an important loss of galactose content and a reduction of the branching of xylan by arabinose in irrigated condition. Water deficit had a profound effect on fruit size, pulp content, cell wall composition and remodelling. Loss of galactose content was not as important, arabinose content was significantly higher in the pectin‐enriched extracts from non‐irrigated condition, and the levels of methylesterification of pectin and O‐acetylation of xyloglucan were lower than in irrigated condition. The lower levels of hydrophobic groups (methylester and O‐acetyl) and the less intensive degradation of the hydrophilic galactan, arabinan and arabinogalactan in the cell wall may be implicated in maintaining the hydration status of the cells under water deficit.     

Evaluation of resistance to different insecticides in field strains of Helicoverpa armigera (Lepidoptera: Noctuidae) in Punjab, Pakistan

Susceptibility of field populations of Helicoverpa armigera (Lepidoptera: Noctuidae) from Punjab, Pakistan to selected insecticides was evaluated using the leaf dip method. The resistance factors varied between populations. The general trends were low to moderate resistance to endosulfan; very low to low resistance to chlorpyrifos and profenofos; very low resistance to spinosad, indoxacarb and thiodicarb; moderate to high resistance to bifenthrin; high to very high resistance to cypermethrin; and very high resistance to lambda-cyhalothrin. Integrated pest management strategies aimed at reducing pesticide application, such as rotating the conventional insecticides having low resistance with newly developed synthetic insecticides and conserving natural enemies, are recommended.     

新疆地衣资源多样性研究进展

在生物多样性中,地衣是一类独特的生物。新疆地衣资源丰富,至今在新疆已定名的地衣有398种,隶属于98属;包括不完全真菌类地衣4属4、种。深入了解新疆地衣物种多样性和其生态环境及地衣的应用价值,有利于合理利用新疆的生物资源,有效保护生态环境。     

乌鲁木齐南部山区岩面生地衣群落特征的研究

应用多元分析中的主分量分析及聚类分析方法对分布在乌鲁木齐南部山区森林生态系统中岩面生地衣群落进行数量分类并对群落结构物种多样性、相似性和均匀度等群落参数进行了比较系统的研究。结果表明,乌鲁木齐南部山区的岩面生地衣共计49种,隶属于4目13科23属,岩面生地衣形成3种群落:(1)湿润石生地衣群落(Hygro-lichen community)定名为疣微孢衣Acarospora verruculosa+粉盘平茶渍A.alphaplaca+斑纹网衣Lecidea tessellata群落;(2)干燥石生地衣群落(Xero-lichen community)定名为多形茶渍Lecanora polytropa+破小网衣Lecideacarpathica群落;(3)高山石生地衣群落(Alpino-lichen community)定名为不等瓶口衣Verrucaria iaequalis+皮果衣Dermatocarpon miniatum群落。同时发现在乌鲁木齐南部山区森林生态系统中岩面生地衣群落的分布与海拔高度和基物的种类有密切的关系,不同海拔的不同类型的森林生态系统中分布着不同种类的岩面生地衣。     

Population survey and conservation assessment of the globally threatened cheer pheasant(Catreus wallichi) in Jhelum Valley,Azad Kashmir,Pakistan

The cheer pheasant Catreus wallichi is a globally threatened species that inhabits the western Himalayas. Though it is well established that the species is threatened and its numbers declining, updated definitive estimates are lacking, so in 2011, we conducted a survey to assess the density, population size, and threats to the species in Jhelum valley, Azad Kashmir, which holds the largest known population of cheer pheasants in Pakistan. We conducted dawn call count surveys at 17 points clustered in three survey zones of the valley, 11 of which had earlier been used for a 2002-2003 survey of the birds. Over the course of our survey, 113 birds were recorded. Mean density of cheer pheasant in the valley was estimated at 11.8±6.47 pairs per km2, with significant differences in terms of both counts and estimated density of cheer were significantly different across the three survey zones, with the highest in the Chinari region and the lowest, that is the area with no recorded sightings of the pheasants, in Gari Doppata. The total breeding population of cheer pheasants is estimated to be some 2 490 pairs, though this does not consider the actual area of occupancy in the study area. On the whole, more cheer pheasants were recorded in this survey than from the same points in 2002-2003, indicating some success in population growth. Unfortunately, increasing human settlement, fires, livestock grazing, hunting, and the collection of non-timber forest products continue to threaten the population of cheer in the Jhelum valley. To mitigate these potential impacts, some degree of site protection should be required for the conservation of cheer pheasants in Pakistan, and more effective monitoring of the species is clearly needed.