孑遗植物银杏(Ginkgo biloba L.)伴性光合生理特征与进化生态

银杏类是一类古老的雌雄异株植物,目前仅存单科单属.由于银杏在系统发育等方面的独特地位,吸引了科学家从不同方面进行了广泛的研究.在适宜的条件下,测定了生长在野外环境下的成年银杏的雌雄个体的光合特性.研究结果表明,银杏的雌雄植株对光具有相同的表现趋势,光饱和点,光补偿点,光下呼吸速率等均没有明显差异.但是雌性银杏的净光合速率明显大于雄性银杏的净光合速率.这种差异可能与雌性个体在繁衍后代时需要投入更多的能量有关.研究也表明,在与其它的裸子植物和被子植物比较时,银杏的光合能力并没有明显的弱势,因此光合能力可能并不是银杏在第三纪分布受限的直接原因.     

孑遗植物银杏(Ginkgo biloba L.)伴性光合生理特征与进化生态

银杏类是一类古老的雌雄异株植物,目前仅存单科单属。由于银杏在系统发育等方面的独特地位,吸引了科学家从不同方面进行了广泛的研究。在适宜的条件下,测定了生长在野外环境下的成年银杏的雌雄个体的光合特性。 研究结果表明,银杏的雌雄植株对光具有相同的表现趋势,光饱和点,光补偿点,光下呼吸速率等均没有明显差异。但是雌性银杏的净光合速率明显大于雄性银杏的净光合速率。这种差异可能与雌性个体在繁衍后代时需要投入更多的能量有关。研究也表明,在与其它的裸子植物和被子植物比较时,银杏的光合能力并没有明显的弱势,因此光合能力可能并不是银杏在第三纪分布受限的直接原因.     

Gender-related differences in adaptability to drought stress in the dioecious tree <Emphasis Type="Italic">Ginkgo biloba</Emphasis>

Ginkgo (Ginkgo biloba) as a precious relict plant is cultivated around the world, and it is also a typical dioecious tree. Drought is a major environmental stress that limits the growth and development of ginkgo. Although many studies have examined the impact of drought on ginkgo, few have investigated gender-related under drought treatment in the species. In our research, we examined comparative morphology, physiology and the ultrastructure of mesophyll cell in male and female ginkgoes to determine which gender shows superior adaptability to drought stress. Two-year-old cutting-propagated male and female ginkgoes suffered to drought treatment. The experiments showed that drought significantly limited growth and development, disrupted photosynthesis, and destoried the antioxidant protection system in both male and female ginkgoes. When the gender differences in the species were compared, females showed better growth, activities of SOD and POD, concentrations of chl t, chl a/b ratio and proline, P _n, C _i, g _s, qP and NPQ under drought, but lower concentrations of H₂O₂ and O₂ ^?, and relative electrolyte leakage. In the aspect of cell ultrastructure, female plants showed a slower rate of cell breakdown and chloroplast decomposition under drought stress than males. The results indicate that female plants of ginkgo show superior growth performance and self-protective mechanisms and higher photosynthetic capacity than male plants under drought stress. Thus, we conclude that female individuals of ginkgo possess better adaptability to drought stress than male individuals.     

临沂生生园复干银杏生长特性

产生复干是银杏个体发育过程中一个普遍现象。本研究以临沂生生园全国最大复干银杏群落为对象,采用每木检尺的方式对园内复干银杏进行调查。结果显示,生生园内银杏共385株,雌株379株,占98.41%;平均树高20.9m,总胸径0.93m,母干胸径0.33m,冠径在5.0-15.0m范围内,枝下高6.3m;17株无复干,复干率为98.58%,每株复干数平均为4.6个,最大复干高为12.5m,胸径0.18m,复干与母干距离为0.61m,复干与母干夹角为10.5?;34株无萌蘖,萌蘖平均株数为38株,萌蘖高1.11m,萌蘖与母干最大距离0.73m。该片银杏林原桩有240年历史,现存复干银杏系从原桩萌发形成,树龄53年。本文对生生园复干银杏的起源、性别比例、复干与银杏适应性的关系等进行了探讨。     

火炬树雌雄母株克隆生长差异及其光合荧光日变化

火炬树(Rhus typhina Linn.)是兼有雌雄异株和克隆生长特性的外来木本植物。分别探讨火炬树雌雄母株克隆繁殖扩散能力的特点,分析其光合荧光反应的差异。采用CIRAS-2光合仪和FMS-2便携调制式荧光仪,并结合样圆调查法,比较火炬树雌雄母株的克隆分株数量和形态生长指标、光合生理参数的日变化特征,揭示火炬树雌雄异株的资源利用效率和对午间强光缓冲保护能力的雌雄差异。研究结果表明:1)火炬树雄性母株的克隆分株形态生长指标及数量均超过了雌性母株,且雄性母株形成克隆分株的年龄早于雌性母株1a;2)火炬树雄性母株的光能、水分和CO2利用效率和净光合速率均高于雌性母株,此结果为雄性母株克隆生长奠定了较为充足的营养基础;3)在晴天自然光的条件下,火炬树雄性母株未出现光抑制,而雌性母株出现了光抑制现象,非光化学猝灭系数(qN)日变化特征显示雌性母株的热耗散程度较高。因此,火炬树雄性母株的克隆生长力强于雌性母株。     

两种中国特有树种的枯叶分解速率

银杏和水杉是我国特有的珍贵树种。本文对北京公园内银杏和水杉林下的枯叶分解速率进行了试验研究。枯叶失重率：放置380天的银杏为55.63%;放置338天的水杉为53.39%。用指数衰减模型估算枯叶的年腐解率,银杏为0.771克／(克·年);水杉为0.824克／(克·年)。根据枯叶的化学成分分析表明,枯叶的失重率和枯叶化学成分净丧失值的变化趋势相一致。枯叶在一年的分解过程中,碳、氮含量比值随时间的推移而下降。     

Potential effets of ginkgo (Ginkgo biloba,L.) on female reproduction

This minireview will briefly outline the basic knowledge concerning the provenance, biological active constituents of ginkgo (Ginkgo biloba, L.) and its general health effects. Ginkgo has been shown to affect female reproductive functions: it can affect ovarian folliculo- and oogenesis, embryogenesis, promote ovarian granulosa cell apoptosis, reduce their proliferation and the release of ovarian hormones. Usually, ginkgo extract mainly suppresses, but its constituents like amifostine, leuprorelin, quercetin and kaempherol can promote ovarian functions. This may indicate the existence of anti-reproductive ginkgo constituent(s), such as ginkgolide B and allopregnenolone which, like ginkgo extract, can promote ovarian cell apoptosis and suppress ovarian follicullogenesis and oogenesis. Ginkgo effects could be mediated by an action on brain functions, ovarian steroidogenesis, oxidative processes, intracellular regulators of ovarian cell proliferation and apoptosis and GABA receptors. Ginkgo and its molecules, ginkgolide B and allopregnenolone can be useful for prevention and treatment of reproduction-related disorders like ovarian cancer, ovarian ischemia and menopausal syndrome. On the other hand, its constituents amifostine, leuprorelin, quercetin and kaempherol could be potentially applicable as biostimulators of female reproductive processes in human and veterinary medicine and animal production. Nevertheless, application of ginkgo is still limited by insufficient or contradictory knowledge concerning its active constituents, characters, targets and mediators of its action and their functional interrelationships. Impact of ginkgo action on reproductive organs other than ovaries remains largely unknown. Addressing these issues with proper animal and clinical studies could help to understand the distinct efficacy and consequences of medical application of ginkgo.     

性别和发育阶段对绒毛白蜡光合特征及叶功能性状的影响

雌雄异株植物资源分配模式上往往表现出显著的性别二态性,但在叶片光合及功能性状上是否有差异目前仍未有定论,且与发育阶段的关系尚不明确。阐明上述问题,能够进一步了解雌雄异株植物的生理生态特征,并为理解性别对性二态植物生长发育的影响机制提供理论依据。以雌雄异株绒毛白蜡(Fraxinus velutina Torr.)为研究对象,针对不同发育阶段不同性别植株进行光合特征及叶功能性状测定,采用双因素方差分析了不同发育阶段下雌雄植株光合能力及叶功能性状的性别间差异,采用Pearson检验了雌雄植株各叶功能性状之间的相关性,并采用标准化主轴分析(Standardized major axis regression, SMA)分析不同性别植株净光合速率与叶功能性状的相关性。结果表明性别和发育阶段显著影响植物个体的光合能力和叶功能性状。总体而言,雄树在坐果期和果实成熟期均表现出更强的净光合速率(Pn)、更高的比叶面积(SLA)、叶绿素含量(Chl)和叶氮含量(LNC);而雌树在果实膨大期表现出更强Pn、SLA和Chl。雌雄性别内Pn与SLA、Chl和LNC间均呈显著正相关(P<0.05),雄树的S...     

银杏幼苗雌雄株对盐胁迫响应的差别

采用对盆栽银杏(Ginkgo biloba)雌雄幼苗浇灌NaCl(40?mmol L-1)溶液模拟土壤受盐胁迫的方法,研究银杏雌雄幼苗气体交换特征、内在水分利用效率(WUE)、游离脯氨酸含量(Pro)、超氧化物歧化酶(SOD)及过氧化物酶(POD)活性在盐胁迫下的差异.结果表明:(1)盐胁迫后雌株的净光合速率、气孔导度以及蒸腾速率与对照相比分别降低45.87%、25.00%、16.47%,而雄株的气孔导度、胞间CO2浓度和蒸腾速率分别升高了10.00%、8.10%、22.95%;(2)盐胁迫显著降低了银杏幼苗的WUE(P=0.020),与对照下相比,雌、雄WUE分别下降30.47%、46.38%;(3)盐胁迫显著提高了雄株的游离Pro含量,但对雌株影响不显著;(4)盐胁迫使银杏雌、雄幼苗SOD活性分别降低了22.96%、23.18%,但下降幅度均不显著.然而盐胁迫会显著降低雌株的POD活性,但对雄株无显著影响.上述结果同时表明,40?mmol L-1的NaCl溶液不仅会降低银杏雌雄幼苗的光合速率,影响气体交换,还会降低WUE、SOD及POD等酶活性,提高游离Pro含量,但雌株受到的负面效应小于雄株.与雄株相比,雌株在盐胁迫下能通过维持较高的光合速率贮藏能量,较低的蒸腾速率和较高的内在水分利用效率以减少水分散失,以及较高的抗氧化物酶活性来缓解盐胁迫带来的氧化胁迫,使其受到的负面影响减小.     

Species-dependence of the pattern of plant photosynthetic rate response to light intensity transition from saturating to limiting one]

By observing the photosynthetic responses of leaves to changes in light intensity and CO(2) concentration it was found that among the more than 50 plant species examined 32 species and 25 species showed respectively the V pattern and L pattern of the photosynthetic response to light intensity transition from saturating to limiting one (Figs.1 and 2 and Table 1). The pattern of photosynthetic response to light intensity transition is species-dependent but not leaf developmental stage-dependent (Fig.3). The species-dependence was not related to classification in taxonomy because the photosynthetic response might display the two different patterns (V and L) in plants of the same family, for example, rice and wheat (Gramineae), soybean and peanut (Leguminosae). It seemed to be related to the pathway of photosynthetic carbon assimilation because all of the C(4) plants examined (maize, green bristlegrass and thorny amaranth) displayed the L pattern. It might be related to light environment where the plants originated. The V pattern of photosynthetic response to light intensity transition was often observed in some plants grown in shade habitats, for example, sweet viburnum and Japan fatsia, while the L pattern was frequently observed in those plants grown in sunny habitats, for example, ginkgo and cotton. Furthermore, the ratio of electron transport rate to carboxylation rate in vivo measured at limiting light was far higher in the V pattern plants (mostly higher than 10) than in the L pattern plants (mostly lower than 5), but the ratio measured at saturating light had no significant difference between the two kinds of plants (Table 2). These results can be explained in part by that the V pattern plant species have larger light-harvesting complex (LHCII) and at saturating light the reversible dissociation of some LHCIIs from PSII reaction center complex occurs. The pattern of photosynthetic response to light intensity transition and the ratio of electron transport rate to carboxylation rate in vivo measured at limiting light can probably be used as a criterion to distinguish sun plants from shade plants. In the observation of photosynthetic response to light intensity transition the use of saturating light is very important because using non-saturating light can form an artifact, which leads to incorrect conclusion (Fig.4).     

PHOTOSYNTHESIS IN THE FEMALE GAMETOPHYTE OF GINKGO BILOBA

The female gametophyte of Ginkgo biloba is the only seed plant gametophyte known to contain chlorophyll. Measurements of photosynthetically active radiation (PAR) indicate that a gametophyte growing within an ovule can receive significant quantities of light (70 μmol photons m^–2 s^–1). Under the conditions of our experiments, whole gametophytes dissected free from ovules were capable of gross photosynthesis, but not net photosynthesis. On a dry wt basis, the maximum rate of carbon fixation under near saturating light intensities was 3.64 × 10^–3 μmol CO₂g^–1 s^–1. The unique ability of the female gametophyte of Ginkgo biloba to produce chlorophyll and engage in photosynthesis appears to result from its exposure to sufficient levels of light and a predisposition to react to this stimulus by the development of a functional photosynthetic apparatus.     

Differences in photosynthetic activity, chlorophyll and carotenoid levels, and in chlorophyll fluorescence parameters in green sun and shade leaves of Ginkgo and Fagus

The differences in pigment levels and photosynthetic activity of green sun and shade leaves of ginkgo (Ginkgo biloba L.) and beech (Fagus sylvatica L.) are described. Sun leaves of both tree species possessed higher levels in chlorophylls (Chl) and carotenoids on a leaf area basis, higher values for the ratio Chl a/b and lower values for the ratio Chl/carotenoids (a+b)/(x+c) in comparison to shade leaves. The higher photosynthetic rates P(N) of sun leaves (ginkgo 5.4+/-0.9 and beech 8.5+/-2.1 micromol m(-2)s(-1)) were also reflected by higher values for the Chl fluorescence decrease ratios R(F)(d) 690 and R(F)(d) 735. In contrast, the shade leaves had lower P(N) rates (ginkgo 2.4+/-0.3 and beech 1.8+/-1.2 micromol m(-2)s(-1)). In both tree species the stomatal conductance G(s) was significantly higher in sun (range: 70-19 1 mmol m(-2)s(-1)) as compared to shade leaves (range: 5-55 mmol m(-2)s(-1)). In fact, at saturating light conditions there existed a close correlation between G(s) values and P(N) rates. Differences between sun and shade leaves also existed in several other Chl fluorescence ratios (F(v)/F(m), F(v)/F(o), and the stress adaptation index Ap). The results clearly demonstrate that the fan-shaped gymnosperm ginkgo leaves show the same high and low irradiance adaptation response as the angiosperm beech leaves.     

Photoinhibition and Photoprotection in Ginkgo biloba leaves: Influence of Temperature,CO2 and O2

In midday ginkgo ( Ginkgo biloba L. ) leaves have to bear photon flux density over 1 400 μmol·m-2·s-l in combination with high temperatures around 35℃ at natural habitat. They show typical midday depression of stomatal conductance and of CO2 assimilation rate. The zeaxanthin changes with light intensity during the day. The influence of the combination of strong light and temperature on photoinhibition was also examined in the laboratory. A low CO2 internal conductance (31 mmol· m- 2·s- 1 ) was found in ginkgo leaves, which had been exposed to excessive light at temperature between 15 ℃ and 35 ℃ with reduced CO2 (80 μL·L-l) or oxygen (2%) for 2 h, causing a low CO2 concentration at the carboxylation site and a high proportion of photorespimtion. The ratio of electron transport to CO2 fixation was rather high in ginkgo ( 16 e- /CO2 at 25 ℃ ) as compared with other plants. It increased with temperature also in 2% 02 which could not be explained solely as due to change of photorespimtion. The reduction of oxygen in 340 or 80 μL·L- 1 CO2 had no effect on the extent of photoinhibition at all temperatures, which indicated that eleetron flow caused by photorespiration in excess light was negligible in protective effect in ginkgo leaves. However, a decreased CO2 coneentration increased photoinhibition, especially at high temperature. It is concluded that the dissipation of excessive excitation energy in the PS II antennae through the xanthophyll cycle may be the major protective mechanism to preventing from the deteriorated effects of strong light in ginkgo leaves.     

基于产量效应的间作紫花苜蓿/禾本科牧草光能利用特征

为探究紫花苜蓿/禾本科牧草间作下光能利用特性、光能利用诸因素的产量效应及其调控机理,通过2017—2019年3年田间试验,以紫花苜蓿、饲用小黑麦(C3植物)、饲用玉米(C4植物)3种单作模式为对照,研究了紫花苜蓿/小黑麦和紫花苜蓿/玉米两种间作模式下的产量效应、光能利用各因子对产量形成的影响、光能利用特征差异及机理。结果表明: 两种间作模式的土地当量比均大于1,表明两种间作模式的土地利用率都高于单作,均有高于单作的产量效益,且增产潜力较大的是紫花苜蓿/小黑麦间作模式。光能利用各因子对产量的贡献依次是: 叶面积指数(1.531)＞净光合速率(0.882)＞胞间CO₂浓度(0.282)＞蒸腾速率(-0.229)＞冠层开度(-0.291)＞光合有效辐射截获率(-0.681)＞气孔导度(-0.751)。其中,叶面积指数不仅是表征光合能力的重要指标之一,更是以收获营养体为目标的牧草作物产量的重要构成因子,光合特性诸因素中净光合速率是影响产量的主要因子。与单作相比,间作下紫花苜蓿、小黑麦、玉米的净光合速率均存在差异,且表现为相同的规律。间作下净光合速率提高的主要途径为: 小黑麦和玉米通过增强CO₂的羧化固定能力,提高对强光的利用能力,从而提高净光合速率,促进产量增加;而紫花苜蓿则是通过提高功能叶的叶绿素b含量,改变叶绿素构成,增强对光能的收集和传递,从而提高净光合速率,促进其在弱光下光合能力的提高和正常生长。     

Photosynthetic responses to variable light: a comparison of species from contrasting habitats

Photosynthetic responses to variable light were compared for species from habitats differing in light availability and dynamics. Plants were grown under the same controlled conditions and were analysed for the kinetics of photosynthetic induction when photon flux density (PFD) was increased from 25 to 800 mol m^-2s^-1. Gas exchange techniques were used to analyse the two principal components of induction, opening of stomata and activation of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco). On average, 90% of the final photosynthetic rate was attained after 7 min for obligate shade plants (two species), 18 min for fast-growing sun plants (seven species from productive habitats) and 32 min for slow-growing sun plants (nine species from unproductive habitats). The rapidity of response of the shade plants was explained by stomata remaining more open in the low-light period prior to induction. This was also observed in two species of deciduous trees, which therefore resembled shade plants rather than other fast-growing sun plants. The slow response of the slow-growing sun plants was the result of lower rates of both Rubisco activation and stomatal opening, the latter being more important for the final phase of induction. The lower rate of Rubisco activation was confirmed by direct, enzymatic measurements of representative plants. With increasing leaf age, the rate of stomatal opening appeared to decrease but the rate of Rubisco activation was largely conserved. Representative species were also compared with respect to the efficiency of using light-flecks relative to continuously high light. The shade plants and the slow-growing sun plants had a higher efficiency than the fast-growing sun plants. This could be related to the presence of a higher electron transport capacity relative to carboxylation capacity in the former group, which seems to be associated with their lower photosynthetic capacities. Representative species were also compared with respect to the ability to maintain the various induction components through periods of low light. Generally, the fast-growing sun plants were less able than the other two categories to maintain the rapidly reversible component. Thus, although the rate of induction appears to be related to the ecology of the plant, other aspects of photosynthetic dynamics, such as the efficiency of using lightflecks and the ability to maintain the rapidly reversible component, seem rather to be inversely related to the photosynthetic capacity.     

银杏与玉米花粉肌动蛋白含量的比较研究

通过免疫印迹鉴定,证明银杏(Ginkgo biloba L.)花粉中存在肌动蛋白。同时对银杏和玉米(Zeamays L.)花粉肌动蛋白含量进行了比较。结果表明,银杏花粉肌动蛋白含量明显少于玉米花粉肌动蛋白含量。SDS-PAGE扫描图谱显示,银杏花粉肌动蛋白含量只有玉米花粉的1/6。两种花粉DNaseⅠ活性抑制结果表明,银杏花粉肌动蛋白含量约为玉米花粉的1/7。     

GENETIC DIFFERENTIATION IN LEAF AND WHOLE PLANT PHOTOSYNTHETIC CAPACITY AND UNIT LEAF RATE AMONG CLONES OF PHLOX PANICULATA

A model population comprising five genotypes of Phlox paniculata was used to investigate differentiation in carbon assimilation amongst those genotypes. Three methods were used to measure carbon assimilation, single leaf photosynthetic capacity, whole plant photosynthetic capacity and unit leaf rate (ULR). Genotypes displayed no significant differences in single leaf photosynthetic capacity and that character did not have a detectable genetic component. However, genotypes showed significant differences in both whole plant photosynthetic capacity and unit leaf rate, and significant genetic components were found for both characters. The differences in whole plant photosynthetic capacity and unit leaf rate are related to differences in plant architecture and modular demography. Erect, self-shading morphs had lower whole plant photosynthetic capacity and unit leaf rate than prostrate morphs. The results suggest that the better measures of physiological parameters for use at the population level will be those which integrate over the whole plant rather than those which only measure performance of parts.     

四种鳃金龟对不同植物挥发物的触角电位反应

华北大黑鳃金龟Holotrichia oblita Falderman、暗黑鳃金龟Holotrichia parallela Motschulsky、小黄鳃金龟Metabolus flavescens Brenske和福婆鳃金龟Brahmina faldermanni Kraatz有不同的寄主范围.本研究采用溶剂提取法...     

银杏雌雄株叶片氨基酸组分及其含量

银杏是雌雄异株植物,依靠种子繁殖,是我国特有的活化石植物,也是重要的观赏树种。作为行道树以雄株为宜。为了有计划地进行定性栽培,就需要对幼龄植株进行早期性别鉴定。许多生理指标都可能作为性别鉴定的依据。通过对银杏中氨基酸含量和组成的分析表明,不同性别植株叶片中均含有被分析的17种氨基酸,各种氨基酸的含量和总含量在单株间没有表现出性别差异,而平均含量却表现出雄株高于雌株,其中胱氨酸和酪氨酸较为突出,分别高出雌株28.24%和40.94%,这是否反映了银杏雌雄的性别差异,值得进一步探讨。尽管脯氨酸含量与花药的正常发育有关,并大大高于雌蕊中脯氨酸的含量,但这一生理指标不适用于营养器官。     

Effects of Red and Blue LED Light on the Growth and Photosynthesis of Barley (Hordeum vulgare L.) Seedlings

According to the action spectrum of photosynthesis, photosynthetic efficiency is highest for red light. However, long-term growth with only red light leads to unfavorable changes in plant morphology, decrease in photosynthetic capacity and plant productivity. Detailed mechanisms behind these changes are still poorly understood. We studied the effects of narrow-band red (RL) and blue (BL) LED lighting on the morphology and photosynthesis of barley (Hordeum vulgare L.) seedlings at 9 days old, when energy for plant growth comes mostly from the endosperm, and light has a mainly morphogenic effect on plant growth. Plants grown with white fluorescent lamps (WL) were used as a control. At this developmental stage, light spectrum had small but significant effects on most morphometric parameters, which may become more prominent as the plant grows. These effects were more pronounced in RL-grown plants and were similar to the ‘shade-avoidance response’, which is unusual as in nature it occurs when the fraction of red light in the spectrum is low. RL-grown plants also had impaired photosynthetic photochemical efficiency (as assessed by PAM-fluorometry and leaf absorption). BL-grown plants had a stronger similarity to control plants in their morphology and photosynthetic characteristics than RL-grown plants; however, they had higher NPQ and different NPQ induction kinetics than WL- and RL-grown plants. Our results suggest that photoregulation of plant morphology and photosynthesis evolutionarily adapted to natural light is miscoordinated in narrow-band LED light. We discuss possible reasons for this miscoordination and for the formation of observed phenotypes on the level of photoreceptors.