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关键词： 连香树   风媒   传粉生物学  

摘要： 对人工栽培24 a生连香树的花期动态、传粉全历程、传粉日进程、柱头可受性、花粉数量等传粉生物学特性进行了研究.结果表明,连香树是风媒植物,其花部特征有许多适合风媒传粉的特点：花先叶开放,花小、无花被、无蜜腺和气味、花粉量大.重力玻片法检测的结果表明,连香树为短距离传粉,其风媒传粉发生在晴朗、昼夜温差大、空气湿度高的3月下旬;花期持续时间为12 d,传粉盛期集中在花药开裂后2-3 d,传粉时间短,具有爆发性.

关键词： 植物生物学   辅助教学网   网络教学  

摘要： 设计并建成了植物生物学辅助教学网,对该网的系统框架体系、功能和特色、系统开发及运行环境等进行了介绍。

关键词： 柳属   白粉病   Uncinula   adunca  

摘要： 介绍了柳树白粉病病原菌Uncinula adunca的生物学特性,揭示了西伯利亚地区该菌在症状、无性型阶段及有性型阶段形成等方面的不同,同时还指出了该病原菌子实体的一些生物学特性。

关键词： 沙米   先锋植物   生物学特征  

摘要： 以石羊河下游荒漠区的古浪明沙咀和民勤西沙窝为研究区,研究了沙米的形态结构特征、种子形态及其萌发特性等,结果表明:沙米植株冠幅大小、第1层侧枝数、根径、根深、根幅和最大根长与株高呈线性正相关关系;地上生物量、地下生物量和总生物量与株高呈二次曲线关系,达到显著正相关;沙米生物量中地上生物量占到绝大部分,地上部分生物量中以10～20 cm生物总量最大,各层生物量逐渐减少;沙米种子的大小、千粒质量、种子含水率在不同生态区域或不同年份之间差异显著;沙米种子自然萌发率不高,在黑暗条件下,可提高其发芽率。

关键词： 翅果油树   传粉生物学  

摘要： 对翅果油树进行了传粉生物学的野外观察和实验表明：（1）翅果油树的花具有自花传粉的结构特征，同时具有蜜腺，又具备异花传粉的特征。传粉者主要是一种家养的蜜蜂。（2）翅果油树花形态结构与传粉者的形态和传粉行为非常协调和适应，昆虫的传粉部位主要是头前部和胸部。（3）蜜腺的产蜜量大，开花后1～2天蜜腺分泌量最大。对传粉昆虫竞争中具明显优势。昆虫的访花频率明显高于同花期的其他植物。（4）翅果油树没有融合生殖现象。

关键词： bioactivation   detoxification   herbicides   secondary metabolism   serine hydrolase   signalling  

摘要： Ester hydrolysis dramatically affects the chemical and biological activity of both xenobiotics and endogenous metabolites in plants. By drawing analogies with organic synthesis, de-esterification reveals functional groups which show novel bioactivity and can undergo subsequent chemical modification. Thus, classically parent esters are hydrophobic, membrane permeable precursors of carboxylic acids which show activity as toxins, signalling agents and pathway intermediates. In plants, a large number of proteins with carboxylesterase activity have been recruited to catalyse these apparently facile reactions. Thus, enzymes that selectively hydrolyse xenobiotic and natural product carboxylesters are derived from three distinct super-families and this is in addition to the many other hydrolases that show this as a secondary activity resulting from their ability to cleave amide and thioester bonds. In this review, the ability of carboxylesterases to control the bioactivity and transport of herbicides, plant signalling agents and secondary metabolites in plants will be considered and recent insights into the identity of the respective enzymes reviewed. (c) 2007 Elsevier Ireland Ltd. All rights reserved.

关键词： Stachybotrys chartarum   S. chlorohalonata   exoantigen   straw   wallboard  

摘要： We are interested in isolating and identifying antigenic fungal proteins from species that grow on damp building materials. Fungal spores contain a modest number of proteins present in high concentrations and mycelia can contain large numbers of such proteins. Their distribution in mycelium when grown on laboratory media often does not reflect their occurrence in nature. Stachybotrys chartarum occurs on wet cellulose based building materials including paper-faced gypsum board and wood. To find potentially characteristic antigenic proteins from this fungus, we screened mycelium and spores from geographically representative strains using sera from a large number of patients who had been identified as having antibodies to fungi that grow in the built environment. Proteins were sought that were common across strains and for which antibodies were present in many sera. The use of human sera as the source of antibodies permitted the conclusion that any proteins of interest were produced in nature. The target proteins were shown to be present in spores/mycelium produced on natural substrata including straw and paper. This report concerns the isolation and partial characterization of a 34-kDa exoantigen. It is a glycoprotein that appears to comprise two subunits with molecular weights of 34 and 21 kDa which are not bound together through disulfide bonds. Both proteins have pIs in the acidic range. The sequences indicate that the protein is related to an extracellular DNase from Nectria haematococca. The partial sequences of the larger subunit are similar to that of a hypothetical protein from Gibberella zeae. (C) 2007 Elsevier Ltd. All rights reserved.

ISBN: (纸本)9787811016505