广西拉沟自然保护区维管束植物资源

据调查,广西拉沟自然保护区有维管束植物186科657属1078种（含变种、亚种）,包括材用植物88种、药用植物358种、油脂植物36种、纤维植物70种、淀粉植物29种、杂果植物25种、芳香植物28种、栲胶植物39种、保健饮料植物12种、饲用植物49种、花卉观赏植物75种、水土保持植物23种、珍稀濒危植物43种等资源植物,保护植物资源迫切而重要,对此提出植物资源保护与可持续利用的建议。     

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.     

浙江瑞安红双林场植物资源及其利用前景

浙江瑞安红双林场共有维管植物167科538属1055种,其中已知有一定利用价值的资源植物715种,隶属于157科429属。按其性质和用途可分为材用植物、药用植物、油脂植物、纤维植物、淀粉植物、食用植物、芳香植物、栲胶植物、保健饮料植物、牧草及饲料植物、保护与改造环境植物、观赏植物、土农药植物、蜜源植物等14类,其中药用植物种类最为丰富。以常见药用植物234种为例,根据植物资源可利用量估量法估量当地植物资源利用前景,结果表明,其中46.2%的常见药用植物可利用量估量值在12以上,可供开发利用。文后提出红双林场植物资源保护与利用建议。     

宁波北仑植物资源及珍稀保护植物研究

宁波市北仑区蕴藏着丰富的植物资源,据调查有野生维管植物158科454属712种,在这些植物中,有药用植物276种、用材树种95种、观赏植物87种、纤维植物60种、防护植物55种、薪炭植物52种、油脂植物48种、饲料植物42种、野生水果38种、芳香植物30种、淀粉植物25种、蜜源植物24种、野菜植物18种等,大多具有开发和可持续利用的价值;此外,北仑还有国家野生重点保护植物4科5属5种、古树名木15科17属17种,这些植物对开发建设中的北仑来说,是极其宝贵的自然资源.因此,为使北仑区的植物资源得到可持续的利用,对其开发利用和保护提出了建议.     

入侵植物筛选方法在我国口岸防控中的应用建议

入侵植物是生物入侵中数量最多的类群,给全世界造成了重大的经济和环境影响。植物入侵的预测研究是口岸防控工作中的重要技术环节之一。本文介绍了入侵植物筛选方法的概念,简述了与之相关的基础理论、研究情况以及3种植物入侵的预测方法。综合来看,入侵植物筛选方法主要采用植物自身的生物生态学特性作为评估指标来筛选外来植物,能快速可靠地将外来植物评判为严重入侵植物、非入侵植物以及介于二者之间的一般入侵植物,因此该方法能为我国口岸防范外来植物入侵的管理提供基础技术支撑。当前我国入侵植物筛选方法的研究和应用尚处起步阶段,通过本文的简述期望引起相关人员对此问题进行探讨,并为我国口岸入侵植物防控工作提供理论参考。     

海南铜铁岭种子植物资源调查

据调查海南铜铁岭有野生种子植物165科681属1279种,其中裸子植物3科3属5种;双子叶植物135科516属1025种;单子叶植物27科152属249种。在这些植物中,有国家重点保护野生植物8种、珍稀濒危植物61种。统计结果表明：有材用植物约401种、药用植物623种、油脂植物86种、芳香植物58种、蜜源植物102种、纤维植物56种、野生果树66种、观赏植物196种、饲料植物51种、绿肥植物22种、杀虫植物24种、单宁植物27种、淀粉植物16种。对其资源特点进行了分析,并对其开发利用和保护提出了建议。     

深圳塘朗山郊野公园的植物资源

广东深圳塘朗山郊野公园共有野生维管植物144科423属611种,分别占广东省维管植物280科1589属5737种的51.4%、26.7%和10.65%;其中蕨类省植物21科29属33种,裸子植物3科3属4种,被子植物120科391属574种,被子植物占绝对优势。国家重点保护野生植物共计7科7属7种,占广东省国家重点保护野生植物的10.9%;珍稀濒危植物有4科5属5种,占广东省珍稀濒危植物67种的7%。公园中经济植物可分为12类,分别是药用植物321种,用材树种65种,观赏植物60种,纤维植物41种,野生水果33种,油脂植物38种,饲料植物42种,鞣料植物42种,野菜植物25种,农药植物27种,芳香植物26种,淀粉植物23种,保健植物19种,染料植物13种,有毒植物10种,蜜源植物5种。     

Exotic vertebrate and invertebrate herbivores differ in their impacts on native and exotic plants: a meta-analysis

Herbivores modify various ecological processes including interactions between native and exotic plants that may affect invasion success by the exotic plants. It is unknown whether different types of exotic herbivores have similar effects on native and exotic plants. Using two distinct data sets, we ran meta-analyses to compare exotic vertebrate and invertebrate herbivore preferences for, and effects on performance and population sizes of native and exotic plants. We found that exotic vertebrate herbivores have positive effects on exotic plant performance and population sizes, and no significant effects on native plants. Exotic invertebrates have significant negative effects on performance and population sizes of both exotic and native plants. Vertebrates prefer to feed on native plants relative to exotic plants, while invertebrates prefer the exotic plants to native plants. Thus the exotic vertebrate herbivores may aid invasiveness of exotic plants, in accordance with the invasional meltdown hypothesis, while exotic invertebrate herbivores probably have no net effect on invasion process of the exotic plants. Invertebrate herbivore preferences for exotic plants support the biotic resistance hypothesis, as the native plants probably resist the invertebrate herbivory. We also tested an evolutionary logic that posits that herbivores with similar evolutionary history as plants will affect the plants less negatively than plants with which they have not co-evolved. Our results indicate that there is no consistent pattern in effects of exotic vertebrate and invertebrate herbivores on exotic plants with or without which they have co-evolved.     

Effect of Ditylenchus dipsaci on Alfalfa Mortality,Winterkill, and Yield

Ditylenchus dipsaci-infected and noninfected alfalfa plants in a naturally infested field were studied from July 1980 to September 1982. Forty-one percent of the plants died during the study. Ninety-seven percent of the plants that died were infected with D. dipsaci. Sixty-nine percent of the observed mortality occurred during winter. Forage yield of infected plants was significantly lower than yield of noninfected plants at each harvest. Stored carbohydrates in infected plants were significantly lower than in noninfected plants. In a controlled environment test, significantly greater mortality occurred in frozen severely infected plants than in frozen noninfected plants, while no mortality occurred in severely infected or noninfected plants that were not frozen. Both forage yield and stored carbohydrates were significantly lower in severely infected than noninfected, non-frozen plants. Mortality in greenhouse-grown plants that were transplanted to field plots was significantly greater in D. dipsaci-infected plants than in noninfected plants after one winter.     

REGENERATION AND SEXUAL DIFFERENTIATION OF GRIFFITHSIA JAPONICA (CERAMIACEAE,RHODOPHYTA) THROUGH SOMATIC CELL FUSION1

Hybrid cells were obtained from somatic cell fusion among male, female, and tetrasporangial plants in Griffithsia japonica Okamura by a wound-healing process. Isolated fusion cells regenerated new mature plants with mixed reproductive structures. The plants regenerated from hybrid cells between male and female plants developed into 1) spermatangiate, 2) carpogonial, 3) bisexual with spermatangia and carpogonial branches, 4) mixed-phase with spermatangia and tetrasporangia, or 5) bisexual/mixed-phase plants with spermatangia, carpogonial branches, and tetrasporangia. About 70% of the plants regenerated from hybrid cells between male and female plants produced tetrasporangia that were always formed with spermatangia on a single cell. Some of those tetrasporangia released tetraspores, six of which gave rise to mature plants. The plants regenerated from hybrid cells between male and tetrasporangial plants developed into spermatangiate, tetrasporangiate, or mixed-phase plants with spermatangia and tetrasporangia. The plants regenerated from hybrid cells between female and tetrasporangial plants developed into carpogonial, tetrasporangiate, or mixed-phase plants with carpogonial branches and tetrasporangia. All types of reproductive structures we re functional.     

Enhanced tolerances of transgenic tobacco plants expressing both superoxide dismutase and ascorbate peroxidase in chloroplasts against methyl viologen-mediated oxidative stress

In order to better understand the role of antioxidant enzymes in plant stress protection mechanisms, transgenic tobacco (Nicotiana tabacum cv. Xanthi) plants were developed that overexpress both superoxide dismutase (SOD) and ascorbate peroxidase (APX) in chloroplasts. These plants were evaluated for protection against methyl viologen (MV, paraquat)‐mediated oxidative damage both in leaf discs and whole plants. Transgenic plants that express either chloroplast‐targeted CuZnSOD (C) or MnSOD (M) and APX (A) were developed (referred to as CA plants and AM plants, respectively). These plant lines were crossed to produce plants that express all three transgenes (CMA plants and AMC plants). These plants had higher total APX and SOD activities than non‐transgenic (NT) plants and exhibit novel APX and SOD isoenzymes not detected in NT plants. As expected, transgenic plants that expressed single SODs showed levels of protection from MV that were only slightly improved compared to NT plants. The expression of either SOD isoform along with APX led to increased protection while expression of both SODs and APX provided the highest levels of protection against membrane damage in leaf discs and visual symptoms in whole plants.     

Interactive effects of lateral shade and wind on stem allometry, biomass allocation, and mechanical stability in Abutilon theophrasti (Malvaceae)

The effects of lateral shade and wind on stem allometry, whole-plant biomass allocation, and mechanical stability were examined for Abutilon theophrasti in a fully factorial glasshouse experiment. Lateral shade from neighboring plants increased stem height by 33% relative to control plants grown individually, despite a decrease in plant dry mass. Intermittent wind decreased stem height by 18% in unshaded plants, but by only 3% in shaded plants. Surprisingly, both lateral shade and wind caused decreases in stem diameter, even with diameter controlled for height, resulting in low diameter?:?height ratios in wind-treated plants relative to untreated plants. Under shade, wind-treated plants had higher root allocation than untreated plants, which allowed wind-treated shade plants to compensate for a low diameter?:?height ratio. This did not occur in the absence of shade, where stem tissue density and root allocation of wind-treated plants did not exceed that of untreated plants. Nevertheless, wind-treated plants experienced low drag relative to untreated plants due to a lower leaf area. Consequently, stem deflections of wind-treated plants did not exceed those of untreated plants at any given windspeed. Our results document a complex interaction between shade and wind on plant morphology and suggest that the nature of this interaction is generally that lateral shade acts to reduce or eliminate thigmomorphogenic responses.     

Internal Water Status of Kinetin-treated, Salt-stressed Plants

Stomatal resistances and turgor pressures were measured during a 12-day period on leaves of bean (Phaseolus vulgaris L. cv. Contender) which were treated with kinetin, were salinized or were treated with kinetin and salinized. Stomatal resistances were highest in salt-stressed plants, and progressively lower in salt-stressed and kinetin-treated plants, control plants, and kinetin-treated plants. Turgor pressures were highest in salt-stressed plants, and progressively lower in control plants, kinetin-treated plants, and salt-stressed and kinetin-treated plants. Stomata appeared to be kept open more widely under kinetin treatment than under control conditions, even when turgor pressures were lower in kinetin-treated plants than in control plants.     

香港瓮缸群岛野生植物资源调查研究

香港瓮缸群岛共有维管植物166种,隶属于69个科138个属,其中蕨类植物7科8属10种,裸子植物2科2属2种,被子植物60科128属154种。瓮缸群岛为香港著名离岛,植被生境无人为干扰,野生植物资源利用度较低,本文通过对瓮缸群岛的植被类型和野生植物资源进行统计分析,结果表明,该群岛可供利用的植物资源共10类,分别为：药用植物103种、观赏植物107种、食用植物21种、牧草及饲用植物23种、材用植物17种、油脂植物22种、芳香精油植物25种、纤维植物13种、鞣料植物11种、有毒植物26种等,都有很高的开发利用潜力,在此基础上提出相应的保育及开发利用建议,旨在更好地保护和合理利用该群岛的野生植物资源。     

Effects of insect-vector preference for healthy or infected plants on pathogen spread: insights from a model

Insects vector many plant pathogens and often have higher or lower densities on infected plants than on healthy plants. Two hypotheses may explain this observation: insects may preferentially orient toward and select one plant type (referred to as orientation preference) or insects may reside on infected plants for longer or shorter periods than on healthy plants (referred to as feeding preference). The effects of feeding preference and orientation preference were compared alone and in combination using a spatially explicit model. With feeding preference for healthy or infected plants, the qualitative relationship between the percentage of plants infected and the rate of pathogen spread was not affected. However, feeding preference for healthy plants increased rates of pathogen spread, whereas feeding preference for infected plants decreased rates of pathogen spread. Unlike feeding preference, orientation preference for healthy and infected plants produced qualitatively different relationships between the percentage of plants infected and the rate of pathogen spread. With orientation preference for healthy plants, the pathogen spread slowly when few plants were infected, but quickly once most plants were infected. In contrast, with orientation preference for infected plants, the pathogen spread quickly when few plants were infected, but slowly once most plants were infected. In sensitivity analyses, we found that assumptions about the latent period (time between infection and when insects can recognize a plant as being infected) and persistence (length of time an insect remains inoculative) altered the aforementioned effects in some cases. The results illustrate that feeding and orientation preference affect pathogen spread differently, highlighting the importance of elucidating the mechanisms that control vector preference for healthy versus infected plants.     

观赏植物花期调控途径及其分子机制

开花期控制对观赏植物的生产和应用具有重要意义。目前关于高等植物成花机理的研究已经取得了突破性进展,为观赏植物花期调控开辟了新途径。该文总结了观赏植物花期调控的途径和方法,并对改良观赏植物花期的技术思路做了初步分析。通过与高等植物成花机制研究的对比分析发现,观赏植物开花机理的研究已有了长足发展,一些观赏植物的转基因研究也取得了丰硕成果。利用分子设计育种途径改良观赏植物的开花期,突破了传统方法的局限性,其研究和应用前景非常广阔。     

鄂尔多斯高原风蚀沙化梁地克隆植物的分布及其与物种多样性的关系

 采用样线法和点样法对鄂尔多斯风蚀沙化梁地上的植物进行了调查,研究了梁地上克隆植物的分布、克隆植物在群落中的重要性及其与群落物种多样性之间的关系。结果表明：1）在梁顶的典型草原植物群落和梁底的滩地盐生植物群落中克隆植物的物种丰富度较高,而在梁坡的沙生植物群落中较少,非克隆植物物种在梁顶出现频率较高,在梁坡和梁底较少;密集型克隆植物物种丰富度的变化与非克隆植物相同,游击型克隆植物在梁顶植物群落中没有出现,在梁坡群落中也很少,而在梁底的滩地中较多。2）梁底群落中克隆植物的重要值高于梁顶和梁坡群落中克隆植物的重要值,梁顶与梁坡群落中非克隆植物的重要值高于梁底群落中非克隆植物的重要值;在梁坡与梁底群落中,克隆植物的重要值都高于非克隆植物的重要值,而在梁顶群落中克隆植物与非克隆植物的重要值之间无差异;梁顶与梁坡群落中密集型克隆植物的重要值高于梁底群落中密集型克隆植物的重要值,而游击型克隆植物的重要值在梁底群落中较高;在梁顶与梁坡群落中,密集型克隆植物的重要值分别高于游击型克隆植物的重要值,而在梁底群落中,密集型克隆植物的重要值低于游击型克隆植物的重要值。3）梁顶的典型草原植物群落中,群落物种多样性随非克隆植物的重要值、克隆植物的重要值、密集型克隆植物的重要值的变化趋势相同,都为抛物线型。梁坡的沙生植物群落中,群落物种多样性与非克隆植物的重要值呈正相关,而分别与克隆植物和密集型克隆植物的重要值呈负相关。梁底的滩地盐生植物群落中,群落物种多样性与非克隆植物的重要值呈正相关,而与克隆植物和游击型克隆植物的重要值呈负相关。     

NaCl胁迫对嫁接黄瓜膜脂过氧化、渗透调节物质含量及光合特性的影响

以日本引进的耐盐品种‘帝王新土佐’南瓜为砧木,以‘津研4号’黄瓜品种为接穗,研究了NaCl胁迫对黄瓜嫁接植株和自根植株的膜脂过氧化、渗透调节物质含量及光合特性的影响。结果表明:在NaCl胁迫下,黄瓜嫁接植株叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)活性均显著高于自根植株,O·2-产生速率及丙二醛(MDA)含量显著低于自根植株,嫁接植株膜脂过氧化轻于自根植株;嫁接植株叶片游离脯氨酸、可溶性糖、可溶性蛋白质等渗透物质含量均显著高于自根植株;嫁接植株的净光合速率(Pn)、气孔导度(Gs)、胞间CO2浓度(Ci)、叶绿素含量均显著高于自根植株;虽然NaCl胁迫抑制光合作用,但嫁接植株仍表现出优势。以上结果证明,嫁接植株耐盐性优于自根植株。     

Effects of virus infection on demographic traits of an agamospermous population of Eupatorium chinense (Asteraceae)

There are few studies of the interaction between wild plants and viruses. In this paper, the incidence of a geminivirus (tobacco leaf curl virus, TLCV) infection, and its effects on mortality, growth and reproduction of its host-plant, Eupatorium chinense, are reported. A total of 221 plants of an agamospermous population of E. chinense were chosen and their demographic behaviour followed over 2 years (1991–1992). The proportion of infected plants differed between years, with fewer plants infected in 1991 than in 1992. Under low virus incidence (35.3% in 1991), infection was significantly associated with taller plants (>80 cm). However, when the incidence of infected plants increased by almost two times (69.1%) in 1992, this tendency disappeared and small plants were also infected. Virus infection had significant effects on mortality of agamospermous plants. Almost half of the initial number of marked plants (n=221) died after 1 year of observations. Of those dead plants (n=105), 86 plants (82%) were infected in 1991, indicating that virus infection was an important, but not the sole cause of mortality. In 1992, 116 plants were alive, and of these, 40% were infected in 1991, indicating that some infected plants survived 1 year. Agamospermous plants were classified in three groups according to the extent of virus infection (plants infected in 2 years, infected in 1 year and uninfected plants) to detect the effect of virus infection on growth of plants of E. chinense. Infected plants had significantly lower growth rates than healthy plants. Infected plants also produced significantly fewer seeds than uninfected plants. Virus infection, however, had no significant effect on the probability of reproduction in plants of E. chinense, suggesting that infected plants may reproduce but with a lower seed output. In this study, we showed that virus infection may have a strong effect on demographic traits and, as a consequence, on fitness components of plants of E. chinense. These effects were higher than those sometimes observed in other plant-herbivore or plant-pathogen interactions.