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关键词： carnivorous plant   cold stratification   ethylene   flowering   freshwater wetlands   germination biology   rootless aquatic plant   seed dormancy  

摘要： Despite the unprecedented global decline in extant populations of Aldrovanda vesiculosa in the last century, little is known about the reproductive biology of this iconic aquatic carnivorous plant. This study aimed to investigate the role of seed-based reproduction in the ecology of ***, with particular focus on the interplay between the regulation of seed dormancy by temperature cues and the efficacy of exogenous ethylene gas to act as a germination stimulant, the desiccation capacity and long-term storage potential of seeds for conservation purposes. Sexual reproduction appears to be extremely limited in both natural and naturalized populations across three continents, with high variability in the success of flowering and seed set between sites and between seasons. Overall, flowering yielded few fertile fruit (6-19% of flowers producing fertile fruit) and seed viability was variable but generally low (29-88%). Fecundity appears to be influenced by seasonal climatic conditions and microhabitat characteristics. Aldrovanda vesiculosa possesses physiologically dormant seeds, with germination stimulated by exposure to ethylene gas (>90% germination) at 25 degrees C. Seeds appear sensitive to desiccation and sub-zero temperature storage, with no germination and markedly reduced embryo growth after storage of seeds for >1month at 15 degrees C and 15% relative humidity or after short-term (24h) storage at -18 degrees C. In the absence of significant conservation and restoration initiatives, the continuing decline of dystrophic freshwater wetland habitats globally leaves *** facing extinction. As the successful long-term storage of seeds appears unfeasible based on the approaches described in this study, other alternatives for germplasm conservation such as cryostorage of vegetative tissues or zygotic embryos must be considered for establishing long-term ex situ collections of critical germplasm.

关键词： Deconstrained bauplans   developmental robustness   evolutionary developmental biology   hopeful monsters   molecular genetics   morphospace   process morphology   root-shoot bauplan   saltational evolution   Dalzellia   Genlisea   Tristicha  

摘要： Background Various groups of flowering plants reveal profound ('saltational') changes of their bauplans (architectural rules) as compared with related taxa. These plants are known as morphological misfits that appear as rather large morphological deviations from the norm. Some of them emerged as morphological key innovations (perhaps 'hopeful monsters') that gave rise to new evolutionary lines of organisms, based on (major) genetic changes. Scope This pictorial report places emphasis on released bauplans as typical for bladderworts (Utricularia, approx. 230 secies, Lentibulariaceae) and river-weeds (Podostemaceae, three subfamilies, approx. 54 genera, approx. 310 species). Bladderworts (Utricularia) are carnivorous, possessing sucking traps. They live as submerged aquatics (except for their flowers), as humid terrestrials or as epiphytes. Most Podostemaceae are restricted to rocks in tropical river-rapids and waterfalls. They survive as submerged haptophytes in these extreme habitats during the rainy season, emerging with their flowers afterwards. The recent scientific progress in developmental biology and evolutionary history of both Lentibulariaceae and Podostemaceae is summarized. Conclusions Lentibulariaceae and Podostemaceae follow structural rules that are different from but related to those of more typical flowering plants. The roots, stems and leaves - as still distinguishable in related flowering plants - are blurred ('fuzzy'). However, both families have stable floral bauplans. The developmental switches to unusual vegetative morphologies facilitated rather than prevented the evolution of species diversity in both families. The lack of one-to-one correspondence between structural categories and gene expression may have arisen from the re-use of existing genetic resources in novel contexts. Understanding what developmental patterns are followed in Lentibulariaceae and Podostemaceae is a necessary prerequisite to discover the genetic alterations that led to

关键词： FLOWERING LOCUS C (FLC)   flowering time   gene expression   high-resolution molecular phenology (HMP)   innatura systems biology   phase lag calendar   phenological modeling   temperature response  

摘要： Phenology refers to the study of seasonal schedules of organisms. Molecular phenology is defined here as the study of the seasonal patterns of organisms captured by molecular biology techniques. The history of molecular phenology is reviewed briefly in relation to advances in the quantification technology of gene expression. High-resolution molecular phenology (HMP) data have enabled us to study phenology with an approach of innatura systems biology. I review recent analyses of FLOWERING LOCUS C (FLC), a temperature-responsive repressor of flowering, along the six steps in the typical flow of innatura systems biology. The extensive studies of the regulation of FLC have made this example a successful case in which a comprehensive understanding of gene functions has been progressing. The FLC-mediated long-term memory of past temperatures creates time lags with other seasonal signals, such as photoperiod and short-term temperature. Major signals that control flowering time have a phase lag between them under natural conditions, and hypothetical phase lag calendars are proposed as mechanisms of season detection in plants. Transcriptomic HMP brings a novel strategy to the study of molecular phenology, because it provides a comprehensive representation of plant functions. I discuss future perspectives of molecular phenology from the standpoints of molecular biology, evolutionary biology and ecology.

关键词： Moth plant   Puccinia araujiae   Cladosporium uredinicola   Hyperparasitisim   Microcyclic rusts   Cryopreservation  

摘要： The rust fungus Puccinia araujiae is proposed as a biological control agent for moth plant (Araujia hortorum) in New Zealand. This pathogen completes its life cycle on this host, it has the capacity of damaging it by producing premature foliage senescence and defoliation, and, it is only known from members of the Oxypetalinae (Apocynaceae). P. araujiae was found to be heavily hyperparasitised by the fungus Cladosporium uredinicola in the field in Argentina. The mode of action of this hyperparasite was investigated and efforts are currently being made to completely eliminate it from a culture of the rust through a combination of superficial disinfection and multiple sequential inoculations. A protocol was developed for long term storage of teliospores of the rust at very low temperatures. Stored spores were shown to maintain their ability to germinate and produce infective basidiospores for up to 12 months. The possible effect of the hyperparasite on the performance of the rust as a biological control agent, should it be introduced into New Zealand, is discussed. (C) 2015 Elsevier Inc. All rights reserved.

关键词： auxin perception   auxin signaling   transcription factors   structural biology  

摘要： Auxin coordinates plant development largely via hierarchical control of gene expression. During the past decades, the study of early auxin genes paired with the power of Arabidopsis genetics have unraveled key nuclear components and molecular interactions that perceive the hormone and activate primary response genes. Recent research in the realm of structural biology allowed unprece-dented insight into: (i) the recognition of auxin-responsive DNA elements by auxin transcription factors;(ii) the inactivation of those auxin response factors by early auxin-inducible repressors;and (iii) the activation of target genes by auxin-triggered repressor degradation. The biophysical studies reviewed here provide an impetus for elucidating the molecular determinants of the intricate interactions between core components of the nuclear auxin response module.

关键词： Oxygenases   Biomolecules   Secondary metabolism   Biosynthesis   Chemistry -- Manipulation  

摘要： Non-heme iron-dependent oxygenases catalyse the incorporation of 02 into a wide range of biological molecules and use diverse strategies to activate their substrates. Recent kinetic studies, including in crystallo, have provided experimental support for some of the intermediates used by different subclasses of this enzyme family. Plant non-heme iron-dependent oxygenases have diverse and important biological roles, including in growth signalling, stress responses and secondary metabolism. Recently identified roles include in strigolactone biosynthesis, O-demethylation in morphine biosynthesis and regulating the stability of hypoxia-responsive transcriptibn factors. We discuss current structural and mechanistic understanding of plant non-heme iron oxygenases, and how their chemical/genetic manipulation could have agricultural benefit, for example, for improved yield, stress tolerance or herbicide development.

关键词： 高中生物学   校本课程   植物调查  

摘要： 校本课程、国家课程、地方课程是我国的三级课程结构。本文就普洱市第一中学植物调查校本课程开发进行探索。

关键词： 繁育系统   传粉生物学   漓江报春苣苔   心叶报春苣苔  

摘要： 以原产于广西阳朔的漓江报春苣苔(Primulina lijiangensis)和心叶报春苣苔(***)2种报春苣苔属植物为试材,从开花生物学、花粉活力和柱头可授性、花粉/胚珠(P/O)比率、访花昆虫种类和访花行为、杂交指数(OCI)以及繁育系统等方面对2种报春苣苔属植物的传粉生物学进行比较研究。结果表明:2种报春苣苔属植物花期长度相近,均约45d,心叶报春苣苔开花较早;前者单花周期短,花小,每花序花多,开花式样大;后者单花周期相对较长,花大,每花序花少,开花式样小;花粉/胚珠比率(P/O)分别为290.85±5.34和331.76±13.08;二者均为雌雄异熟(雄蕊先熟),柱头和花药存在空间隔离,可以避免自花传粉,但自交亲和,需要依靠传粉媒介完成异花传粉或自花传粉,传粉者黄纹无刺蜂(Trigona ventralis)扮演很重要的角色,相同的传粉者在不同的物种中表现出不同的传粉行为;二者OCI指数均≥4,为异交型,自交亲和,不存在无融合生殖现象,自然授粉结实率均低于人工授粉结实率,前者自然结实率高于后者自然结实率,二者自然结实率差异不显著。

关键词： 微课   植物生物学   实验教学  

摘要： "植物生物学"是一门历史悠久、知识体系完善的课程,在该课程实验教学中有一半的实验需要在显微镜下观察植物切片,而在观察过程中,学生普遍存在找位不准、难以抓住观察要点等问题,这对教学效果和学生的学习兴趣影响很大。因此,如何让实验教学更加直观生动来激发学生的学习热情,是"植物生物学"课程实验教学改革亟待解决的问题。基于微课本身灵活生动的特点,在实验教学中应用微课并建立微课库,是解决该问题的可行方式之一。

关键词： 美容产品   植物生物学   产品介绍   发展现状  

摘要： The Amway Botanical Research Center （ABRC） focuses on plants associated with Traditional Chinese Medicine （TCM） for potential future use in Amway＇s health and beauty products. The ABRC is built on 34-hectares （84-acres） of farmland. It includes an advanced laboratory, large greenhouse and will be used for research on soft nutrients, plant physiology, extract quality standards and processes.