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关键词： Uca annulipes   population structure   reproductive biology   Mozambique   East Africa  

摘要： The community structure of the tropical fiddler crab Uca annulipes (H. Milne Edwards) has been studied in Mozambique for the first time. Ten 0.25 m(2) squares were randomly sampled on a monthly basis during low tide periods from January to December 2002 at Costa do Sol Mangrove, Maputo Bay., southern Mozambique. A total of 981 crabs were captured. of which 494 were males (50.36%) 231 non-ovigerous females (23.85%) and 253 ovigerous females (25.79%). The overall size frequency distribution was unimodal, with males being largest than both ovigerous and non-ovigerous females. Females were more abundant in the smallest size classes while males outnumbered females in the largest ones. The overall sex ratio (1:0.99) did not differ from the expected 1:1 proportion, but significant deviations were observed in January. April, August and November. Results indicate that the size frequency distributions of this species can also be determined through direct analysis of burrow openings. Breeding took place year-round with two peaks of spawning in summer (January and December). Recruits were present throughout the year, with high abundance in summer probably due to the high reproductive activity observed in this season. The present results may allow us to suggest that U. annulipes follows a rapid breeding cycle accompanied by a rapid larval development and settlement in the study area. (C) 2004 Elsevier Ltd. All rights reserved.

关键词： circadian rhythm   flowering   illumination   light relations   localization   photomorphogenesis   phototropism   phytochrome   proteolysis   reviews   signal transduction  

摘要： Light signals acting through photoreceptors and signal transduction chains shape plant growth, development, physiology and metabolism to best suit the organism to the prevailing conditions. Genetic, biochemical and molecular studies, particularly in the model system Arabidopsis thaliana, have produced highly detailed descriptions of many light responses so that now molecular pathways are coming into view. In this review the current state of research in several diverse areas within the field of plant photomorphogenesis is discussed. The topics include phytochrome localization and interactions with signalling elements, cryptochrome function, phototropin photochemistry and physiology, the role of proteolysis in light signalling, the plant circadian clock, and the transition to flowering.

关键词： Golgi apparatus   green fluorescent protein   membrane trafficking  

摘要： The higher plant Golgi apparatus, comprising many individual stacks of membrane bounded cisternae, is one of the most enigmatic of the cytoplasmic organelles. Not only can the stacks receive material from the endoplasmic reticulum, process it and target it to the correct cellular destination, but they can also synthesise and export complex carbohydrates and lipids and most likely act as one end point of the endocytic pathway. In many cells such processing and sorting can take place while the stacks are moving within the cytoplasm and, remarkably, the organelle manages to retain its structural integrity. This review considers some of the latest data and views on transport both to and from the Golgi and the mechanisms by which such activity is regulated.

关键词： 黄褐毛忍冬   生物学特性   形态解剖   喀斯特  

摘要： 本文从形态解剖、生长发育的节律、光合生理特性以及种子萌发生理等生物学特性方面对喀斯特适生经济植物黄褐毛忍冬(Lonicerafulvotomentosa)进行了较为系统的研究,得出以下结论:(1)在形态解剖上,黄褐毛忍冬根茎中含有发育良好的周皮和输导组织,导管密度大,横截面宽,周皮的形成具有节制蒸腾、通气作用和保护组织免受外界环境影响的作用,宽的导管对水分的输导效率高;叶片密被绒毛,面积较小,气孔密度大、开度小,厚的角质层和发育良好的木质部和栅栏组织等是典型的旱生结构;黄褐毛忍冬花粉近球形,具3 孔沟,表面具均匀分布的小刺,刺间具网状纹理。花粉形态是分类学上的一个重要特征,对种及种下的分类有重要意义;成熟的果实具种子 1～18 粒不等,单个果序果多者可达 135 个浆果,果径 0.7～0.8cm。(2)在生长发育上,黄褐毛忍冬具有发达的根系,分枝能力强,根以 4 月上旬至 8 月下旬生长最快,茎的年生长量 30～300cm,10 龄以上黄褐毛忍冬冠幅最大可达 24m2 ,地径可达 8cm;3～4 年生黄褐毛忍冬可开花结实,一个节间可开 10～22 束花,一株最多开花25 斤,花的药用价值很高。(3)在生理上,黄褐毛忍冬蒸腾速率日变化呈双峰曲线,光合速率的日变化为单峰曲线,并受到光照强度、大气温度、大气相对湿度等环境因子综合作用的影响,其中温度对蒸腾速率的影响最大,相关系数为 0.752,光照强度对光合速率的影响最大,相关系数为 0.759,气孔开度的日进程与蒸腾速率日进程趋势相一致;黄褐毛忍冬水分利用效率最高值出现在上午 8:00 左右;用赤霉素浸泡处理能使黄褐毛忍冬种子发芽迅速而整齐,25℃以下时,种子的发芽率随着温度的下降而逐渐下降,而 28℃时的发芽率与 25℃基本保持一致,光照条件下的发芽率略高于黑暗中的发芽率。因此,黄褐毛忍冬生态效益好,药用价值高,具有一定的耐干旱,耐瘠薄,强抗寒的能力,把黄褐毛忍冬作为主要的经济、生态资源植物之一,在贵州省典型的喀斯特地貌区花江大峡谷引种栽培,已经获得成功。

ISBN: (纸本)7030166299

ISBN: (纸本)7030085892

关键词： 铅   镉   重金属抗性菌株   生物学特性   活化   植物修复  

摘要： 植物修复土壤重金属污染技术具有绿色廉价、操作简单等优点，但是超积累植物往往生物量低、生长速度慢、受土壤环境影响大、对固定态和沉淀态的重金属不易吸收。而现有的添加螯合剂、表面活性剂等化学物质强化植物修复的措施又存在修复成本较高，环境风险大的不足，因此寻求一条既能大幅度提高植物修复效率、又能改善土壤生态环境，环境友好且成本低廉的新的微生物强化植物修复途径，将具有重要的理论意义和现实意义。 本研究从46个土样中筛选出对重金属铅镉具有较强抗性和活化能力的菌株J34、J113、J115、J116和J156，初步鉴定J34属于欧文氏菌属(Erwinia sp．)，J113和J116属于氮单胞菌属(Azomonas spp．)，J115和J156属于假单胞菌属(Pseudomonas spp．)。研究温度、pH、渗透压、氧气、重金属、抗生素及多环芳烃对菌株生长的影响，试验结果表明菌株J34、J113、J115、J116和J156均为好氧菌，能在12～37℃和pH5.5～9.0范围内生长良好，最适生长温度28℃，最适pH7.2左右，最适接种菌龄15h左右。菌株J116、J113和J156对高渗条件适应性强，在NaCl5％条件下能良好生长。菌株J34和J116对重金属和抗生素的抗性较普遍，除Cr外对其他重金属和抗生素均具抗性;菌株J113能耐受Ni10mg．L、Zn400mg．L、Amp400mg．L和Rif20mg．L，而对Cu、Cr、Km、Tc和Str无抗性;菌株J156能耐受Cu20mg．L、Zn200mg．L、Amp400mg．L和Rif20mg．L，对Ni、Cr、Km、Tc和Str无抗性;菌株J115除了能抗Zn200mg．L和Amp100mg．L外，对其他重金属和抗生素均无抗性。5株菌均能耐受一定浓度的菲和芘。 通过在有氮培养液中分别添加Pb(NO)、CdSO、PbCO和CdCO与培养液成分反应形成不溶性铅镉，研究摇瓶条件下菌株对沉淀态铅镉的活化能力，结果表明5株菌能使培养液中离子态铅镉的浓度显著增加，Pb浓度比对照(1.59mg．L)高56.54～312.54mg．L，Cd浓度比对照(1.94mg．L)高42.05～50.06mg．L。测定J34、J113和J116培养液中氨基酸，发现酸性氨基酸的浓度高于碱性氨基酸。土壤试验表明，菌株对土壤中沉淀态铅镉也具有活化作用，接菌处理的土样中水溶性铅镉含量均高于

关键词： biological control   developmental parameters   Florida everglades   invasive species   native range studies   plant-feeding mites  

摘要： The biology and phenology of the eriophyid mite, Floracarus perrepae Knihinicki and Boczek,a potential biological control agent of Lygodium microphyllum (Cav.) R. Br., was studied in its native range - Queensland, Australia. F. perrepae forms leaf roll galls oil tile subpinnae of L. microphyllum. It has a simple biology, with females and males produced throughout the year. Tile Population was female biased at 10.5 to 1. The immature development time was 8.9 +/- 0.1 and 7.0 +/- 0.1 days;adult longevity was 30.6 +/- 1.6 and 19.4 +/- 1.2 days and mean fecundity per female was 54.5 +/- 3.2 and 38.5 +/- 1.6 eggs at 21 and 26 degrees C, all respectively. Field studies showed that tile mite was active year round, with populations peaking when temperatures were cool and soil moisture levels were highest. Two species of predatory mites, Tarsonemus sp. and a species of Tydeidae, along with the pathogen Hirsutella thompsonii, had significant effects oil all life stages of F. perrepae. Despite high levels of predators and the pathogen, F. perrepae caused consistent damage to L. microphyllum at all the field sites over the entire 2 years of the study.

关键词： 蒙古扁桃   荒漠植物   濒危植物   生物学特性  

摘要： 蒙古扁桃(Prunus mongolica Maxim.)为蒙古高原荒漠区和荒漠草原特有的落叶灌木,是这些荒漠区和荒漠草原的景观植物和水土保持植物,是蒙古高原古老残遗植物,是药用植物和木本油料植物,属于国家三级保护濒危植物,具有较高的研究、开发价值。本文从开发利用角度分析了蒙古扁桃的种子成分,从保护生物学角度研究了其种子萌发过程的生理生化变化特性及其幼苗、成年植株的水分生理特性和这些生理生化特性在干旱胁迫下的变化。实验结果表明,蒙古扁桃种子粗蛋白质含量为26.77%,其蛋白质氨基酸种类齐全,含18 种氨基酸,必需氨基酸与非必需氨基酸比例适当,与人体适宜蛋白质鸡蛋蛋白质的贴近度为0.876,其蛋白质营养价值优于大豆蛋白质。蒙古扁桃种子富含油脂,粗脂肪含量达51% ,脂肪酸种类较单一,只含油酸、亚油酸、棕榈酸和硬脂酸等四种脂肪酸,而且不饱和脂肪酸油酸和亚油酸占97%。实验证明,干旱胁迫下蒙古扁桃种子活力下降,认为在干旱胁迫下种子活力下降是造成其濒危的原因之一。在蒙古扁桃萌发过程中,干旱胁迫对其脂肪酶活性有抑制作用,结果脂肪水解受抑,游离脂肪酸含量增量进程被延缓。蒙古扁桃种子萌发过程中可溶性糖主要是由脂肪酸转化而来的,因此萌发初期含量很低,以后逐渐增加,但是其增量低于对照组。蒙古扁桃幼苗根吲哚乙酸氧化酶活力分析表明,用5%PEG 和8%PEG 模拟干旱胁迫处理后其吲哚乙酸氧化酶活力比对照低2.72 倍和7.00 倍。在正常水分状况下蒙古扁桃幼苗具有较低的含水量(68.7%)、较低的叶水势(-0.85MPa)、较高的束缚水含量(39.9%)、