论植物医生

随着植物医学的不断发展,植物医生这一称呼逐渐进入公众视野,植物医生这一职业也逐渐开始崭露头角.本文论述了植物医生的概念、职责及其特殊性,解析了植物医生的基本特征、地位和作用,比较了植物医生与人医及兽医的区别,论述了植物医生的价值内涵,着重分析了植物医生与植物保护工作者的区别,全科植物医生和专科植物医生的功能,并系统阐释了植物医生的培养模式和发展方向,以期为全面理解植物医生提供一定的参考.     

从生态学角度看植物医学与植物健康

本文从生态学角度对植物医学和植物健康进行了深度思考,论述了同时从宏观和微观角度进行研究对植物医学学科的重要性,强调了植物群体健康在植物医学中的作用,分析植物医学观念下的自然生态系统与农田生态系统的功能,给出了基于生态学的植物健康和植物医学的新定义.     

贵州师范大学植物标本室的历史与沿革

自2017年参加“国家标本资源共享平台”植物子平台以来,贵州师范大学地理与环境科学学院植物标本室除了数字化植物标本以外,还挖掘、整理了贵州师范大学植物分类学、植物地理学的建设和发展历程。经过3年的艰苦努力,最后向中国数字植物标本馆(CVH)提供了10 044份信息齐全的植物标本。通过此次植物标本数字化工作,彻底摸清了贵州师范大学地理与环境科学学院植物标本的家底,盘活了标本室的库存,使得老一辈植物地理学家黄威廉等老先生60余年的科研成果重新展现在世人面前。通过植物标本的数字化工作,挖掘整理出老一辈精彩的植物标本采集史和学术故事。在标本数字化的过程中,学生和老师都对植物标本以及植物标本背后的故事有了新的认识,对植物标本数字化的重要性和必要性也有了更深的体会。     

土壤有机污染植物修复的机理与影响因素

在综述大量国内外文献的基础上,分析了土壤有机污染植物修复的机理,重点介绍了国内外在植物吸收转运、植物根际降解和植物修复模型的研究进展。同时,从污染物的物理化学性质、植物种类、土壤性质、共存有机物和气象条件5个方面分析了影响土壤有机污染植物修复的主要因素,并展望了该领域的研究方向：深化植物修复机理,完善植物修复模型。加强植物-微生物协同修复的机理研究和技术应用,利用表面活性剂提高植物修复效率,加强复合有机污染植物修复研究。     

害虫天敌的植物支持系统

保护天敌,使天敌长期有效地控制害虫是保护性生物防治的核心内容。其中,植物在维持和促进天敌控制害虫中的重要性和作用越来越受到关注。本文概述了各种支持天敌发挥效能的植物类群,论述了蜜源植物、储蓄植物、栖境植物、诱集植物、指示植物、护卫植物等在支持天敌生存和繁殖方面的生物功能,评述了研究和应用这些植物时需注意的问题,提出了科学利用这些植物以维持和增强农业生态系统中天敌发挥控害作用的植物支持系统,并指出了由于对这些植物类别的界定和定义模糊所带来的不便,给出了相应的建议。     

放牧对草原植物功能性状影响研究进展

植物功能性状的表达和植被环境适应性相关,植物功能性状之间的权衡变化体现了植物在放牧胁迫下资源的重新整合和获取.本文总结了放牧干扰下植物功能性状表达的差异性,着重将放牧干扰与植物功能性状相结合,介绍了植物功能性状的变异来源是植物遗传特征与环境过滤相互协调的结果,归纳了放牧对植物营养性状、繁殖性状的影响,以及植物可以通过调...     

湖北大洪山野生植物资源调查研究

大洪山位于湖北省中北部,地处中纬度北亚热带季风气候带,植物种类非常丰富。初步统计大洪山共有野生资源植物1137种,隶属于132科、529属。对大洪山的野生植物资源按其性质和用途分为观赏植物、能源植物、药用植物、油脂植物、蜜源植物、纤维植物、淀粉及糖类植物、芳香植物、鞣料植物、饲用植物、土农药植物、树脂及树胶植物,并对其进行了统计和分析。文中列举了一些有代表性、经济价值较高的植物种类,分析了该地区野生植物资源的特点及存在问题,提出了合理开发利用植物资源的建议。     

西双版纳热带植物园引种植物个体适应性研究

本研究通过比较引种植物和本土植物的生长状况,主要是果熟现象,讨论了引种植物对引种目的地的适应性。中国科学院西双版纳热带植物园,引种和保存了国内外万种以上的热带和亚热带植物,并对多种引种植物进行了长期连续生长监测。本文统计分析了其中观测4年以上的569个编号的引种植物生长适应状况。结果表明：1）引种植物基本适应植物园的环境,但是不同气候区来源的植物适应性表现不同,不同地区来源植物适应性顺序为：热带亚洲植物〉亚热带和热带北缘植物／热带非洲植物〉热带澳洲植物〉热带美洲植物;2）不同科属植物个体适应表现也有差别,无患子科,蝶形花科,楝科和紫葳科等的植物个体适应性和本土植物比较相似,而大戟科植物个体适应性和本土植物差异最大;3）分析表明引种植物对植物园的适应受到来源地气候和区系起源两个因素的影响;4）紫蒇科,桃金娘科和含羞草科的一些引种植物个体果熟年比高于本土植物,其入侵性有待于进一步入评估。     

植物几丁质酶的基因工程与分子生物学研究进展

植物几丁质酶具有广泛的生理活性,尤其在植物的抗病性方面具有重要作用,因而植物几丁喷酶基因工程或为目前抗真菌基因工程研究的热点。本介绍了植物几丁质酶基因结构的研究进展,综述了植物几丁质酶基因工程和微生物产几丁质酶转入植物的基因工程研究成果,概述了植物几丁质酶分子比较和分子进化研究,并展望了植物几丁质酶基因工程的应用前景。     

广西十万大山自然保护区植物资源

本文报道了广西十万大山自然保护区植物资源,介绍其中主要的材用植物、药用植物、油脂植物、纤维植物、淀粉植物、杂果植物、芳香植物、栲胶植物、保健饮料植物、饲用植物、花卉观赏植物、水土保持植物、珍稀濒危植物等13类资源植物,最后提出植物资源保护与开发利用的建议.     

Oviposition by Danaus plexippus in relation to cardenolide content of three Asclepias species in the southeastern U.S.A.

Abstract. 1. Female monarchs were observed in the field ovipositing on a native North American milkweek host, Asclepias humistrata L. As in a comparable Australian study on an introduced novel host ( Asclepias fruticosa L.) we found post-alighting rejection of plants with low and high cardiac glycoside concentration (CG).
2. Most oviposition took place on plants with CG in the range 200–500 μg/0.1 g dry weight. Thin-layer chromatography showed no obvious qualitative difference in cardenolide types between accepted and rejected plants, excepting an indication that rejected plants may have a higher level of more polar cardenolides.
3. In a controlled laboratory experiment comparing oviposition on a low ( A.incarnata L.) vs high ( A.curassavica L.) CG host plant species we found no relationship between CG and oviposition on the low CG species, but a negative relationship in the high CG species. This corroborates our findings on oviposition on single host species in the field.
4. We also record the first indication of a physiological cost of monarch larvae feeding on plants high in CG. There was a significant negative relationship between survival of first instar larvae and CG levels in plants. This study opens the way for further work on the association of monarch butterflies and their toxic milkweed hosts.     

Cardiac glycosides of the root bark of Nerium odorum

In addition to the known odorosides, the β-d-digitaloside and β-d-glucosyl-(1 → 4)-β-d-digitaloside of uzarigenin were isolated from the root bark of Nerium odorum. Odoroside B was obtained in remarkably high yield among the digitoxigenin and uzarigenin glycosides. With the aid of polyamide column chromatography, oleandrigenin β-gentiobiosyl-(1 → 4)-β-d-digitaloside ( = 16-O-acetylneogitostin) was isolated along with other oleandrigenin glycosides.     

Isoform-specific stimulation of cardiac Na/K pumps by nanomolar concentrations of glycosides

It is well-known that micromolar to millimolar concentrations of cardiac glycosides inhibit Na/K pump activity, however, some early reports suggested nanomolar concentrations of these glycosides stimulate activity. These early reports were based on indirect measurements in multicellular preparations, hence, there was some uncertainty whether ion accumulation/depletion rather than pump stimulation caused the observations. Here, we utilize the whole-cell patch-clamp technique on isolated cardiac myocytes to directly measure Na/K pump current (I(P)) in conditions that minimize the possibility of ion accumulation/depletion causing the observed effects. In guinea pig ventricular myocytes, nanomolar concentrations of dihydro-ouabain (DHO) caused an outward current that appeared to be due to stimulation of I(P) because of the following: (1) it was absent in 0 mM [K(+)](o), as was I(P); (2) it was absent in 0 mM [Na(+)](i), as was I(P); (3) at reduced [Na(+)](i), the outward current was reduced in proportion to the reduction in I(P); (4) it was eliminated by intracellular vanadate, as was I(P). Our previous work suggested guinea pig ventricular myocytes coexpress the alpha(1)- and alpha(2)-isoforms of the Na/K pumps. The stimulation of I(P) appears to be through stimulation of the high glycoside affinity alpha(2)-isoform and not the alpha(1)-isoform because of the following: (1) regulatory signals that specifically increased activity of the alpha(2)-isoform increased the amplitude of the stimulation; (2) regulatory signals that specifically altered the activity of the alpha(1)-isoform did not affect the stimulation; (3) changes in [K(+)](o) that affected activity of the alpha(1)-isoform, but not the alpha(2)-isoform, did not affect the stimulation; (4) myocytes from one group of guinea pigs expressed the alpha(1)-isoform but not the alpha(2)-isoform, and these myocytes did not show the stimulation. At 10 nM DHO, total I(P) increased by 35 +/- 10% (mean +/- SD, n = 18). If one accepts the hypothesis that this increase is due to stimulation of just the alpha(2)-isoform, then activity of the alpha(2)-isoform increased by 107 +/- 30%. In the guinea pig myocytes, nanomolar ouabain as well as DHO stimulated the alpha(2)-isoform, but both the stimulatory and inhibitory concentrations of ouabain were approximately 10-fold lower than those for DHO. Stimulation of I(P) by nanomolar DHO was observed in canine atrial and ventricular myocytes, which express the alpha(1)- and alpha(3)-isoforms of the Na/K pumps, suggesting the other high glycoside affinity isoform (the alpha(3)-isoform) also was stimulated by nanomolar concentrations of DHO. Human atrial and ventricular myocytes express all three isoforms, but isoform affinity for glycosides is too similar to separate their activity. Nevertheless, nanomolar DHO caused a stimulation of I(P) that was very similar to that seen in other species. Thus, in all species studied, nanomolar DHO caused stimulation of I(P), and where the contributions of the high glycoside affinity alpha(2)- and alpha(3)-isoforms could be separated from that of the alpha(1)-isoform, it was only the high glycoside affinity isoform that was stimulated. These observations support early reports that nanomolar concentrations of glycosides stimulate Na/K pump activity, and suggest a novel mechanism of isoform-specific regulation of I(P) in heart by nanomolar concentrations of endogenous ouabain-like molecules.     

弯蕊开口箭中的新甾体配糖体

从百合科植物弯蕊开口箭（Tupistra Hook,f．）的根茎中分离得到4个新的甾体配糖体,分别命名为弯蕊苷（wattoside)B-E(1-4),其中,3个多羟基呋甾型配糖体,另1个为强心苷,经化学降解和光谱分析,其化学结构分别鉴定为：22－0－甲基－25（R,S）,－呋甾烷－1β,3β,4β5β,22ξ,26β－六醇－26－O－β－D－葡萄吡喃糖苷（1）：22－O－甲基－26－O－β－D-葡萄吡喃糖基－25（S）－呋甾烷－5－烯－β,3β,22ξ,26β－甲醇－3－0－[O-β-D-葡萄吡喃糖基（1－4）]－β－D-半乳吡喃糖苷（2）;22－0－甲基－25（S)-呋甾烷－1β,2β,3β,4β,5β,22,26β－七醇－26－O-β－D－葡萄吡喃糖苷（3）和夹竹桃苷元－3－O－[O-β-D-葡萄吡喃糖基（1－2）]－α－L－鼠李吡喃糖苷,弯蕊苷E为开口箭属植物中首次分离到的强心苷。     

Integrative Analyses of De Novo Mutations Provide Deeper Biological Insights into Autism Spectrum Disorder

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Contrasting consequences of plant domestication for the chemical defenses of leaves and seeds in lima bean plants

Plant domestication is assumed to result in reduced levels of defensive compounds in crops, because this makes the plants more suitable for consumption by humans and livestock. We argue that this should mainly be reflected in the concentrations of defense compounds in the plant parts that are used for consumption and not necessarily for other parts of crop plants. We tested this hypothesis for domesticated lima bean (Phaseolus lunatus), by comparing its chemical defenses against a leaf herbivore, the beet armyworm (Spodoptera exigua), and a seed predator, the beetle Zabrotes subfasciatus. For seeds and leaves we determined the concentrations of cyanogenic glycosides (CNGs) in cultivated varieties and wild populations and evaluated the preference and performance of the herbivores when exposed to leaves and seeds from wild and cultivated plants. Concentrations of CNGs were significantly different between wild and cultivated plants. In the leaves the concentration of CNGs in the cultivated varieties were more than double that of the wild leaves. In contrast, seeds from cultivated plants had up to 20 times lower CNG concentration compared to seeds from the wild populations. Insect preference and performance do not parallel the chemical data. Larvae of S. exigua preferred wild leaves but had higher survival on cultivated leaves. The beetles, however, strongly preferred seeds from cultivated plants and females developed more quickly on these seeds. We conclude that domestication of P. lunatus has altered the concentration of CNGs in both the seeds and the leaves in opposite directions. This results in differential effects on the herbivores that attack these two plant structures. The contrasting effect of domestication on different plant tissues can be explained by the fact that bean plants have been specifically selected for human consumption of the seeds. Tissue-specific effects of plant domestication on plant defenses can be expected for other crops as well.     

夹竹桃科植物中强心苷的分布及其药理活性研究进展

本文概述了夹竹桃科植物中强心苷的分布及国内外从夹竹桃科植物中分离得到的强心苷类化合物药理活性研究进展。     

Subcellular localization of glucosyltransferases involved in cardiac glycoside glucosylation in leaves of Convallaria majalis

The glucosylation of convallatoxin and convallatoxol was investigated using homogenates and various subcellular fractions from leaves of Convallaria majalis. The enzyme activity reached a maximum about 5 weeks after the onset of flowering and was found distributed among the soluble and the light membrane fraction. Upon separation of the light membranes by sucrose density gradient centrifugation, glucosyltransferase activity was found solely in a fraction banding at a density of 1.07 g/cm³, which is thought to represent vacuole membranes.     

Properties and genetic control of udp-l-rhamnose: anthocyanidin 3-O-glucoside, 6″-O-rhamnosyl-transferase from petals of red campion,Silene dioica

In petals of Silene dioica plants the presence of a glycosyltransferase has been demonstrated, which catalyses the transfer of the rhamnosyl moiety of UDP-l-rhamnose to the glucose of cyanidin 3-O-glucoside. This enzyme can also use pelargonidin 3-O-glucoside as a substrate. The enzyme activity is controlled by a single dominant gene N; no rhamnosyltransferase activity is found in petals of n/n plants. The rhamnosyltransferase exhibits an optimum of pH 8.1 and is stimulated by the divalent metal ions Mg, Mn and Co. The biosynthetic pathway for the synthesis of cyanidin 3-rhamnosylglucoside-5-glucoside in petals of S. dioica is discussed.     

Uptake,Transport and Storage of Cardenolides in Foxglove. Cardenolide Sinks and Occurrence of Cardenolides in the Sieve Tubes of Digitalis lanata1

Cardiac glycoside transport was investigated on the organ and whole plant level. Uptake experiments were carried out with shoot and root cultures of Digitalis lanata. In both systems primary cardenolides, i.e., those with a terminal glucose in their oligosaccharide side chain, were taken up against their concentration gradient, whereas the glucose-free secondary cardenolides were not. Active uptake of primary cardenolides was further evidenced by KCN inhibition of uptake. Using plantlets grown in vitro the long-distance transport of primary cardenolides from the leaves to the roots was demonstrated. Cardenolides were also detected in etiolated leaves, induced on plants with green leaves, which are supposed to be unable to synthezise cardenolides de novo, providing further evidence for long-distance transport. Several primary cardenolides were detected in the honeydew excreted by aphids fed on Digitalis lanata leaves, indicating that the phloem is a transporting tissue for cardenolides. On the other hand, the xylem sap obtained by applying the pressure-chamber technique was cardenolide-free. It was concluded that in Digitalis primary cardenolides serve as both the transport and the storage form of cardenolides. After their synthesis they are either stored in the vacuoles of the source tissue or loaded into the sieve tubes, from which they are unloaded at other sites where they are trapped in the vacuoles of the respective sink tissue.