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Pollen limitation and variation in floral longevity in gynodioecious Potentilla tanacetifolia

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Journal of Systematics and Evolution 2011年第6期49卷 539-545页

作者： 1,2Hong YAO 1Yi-Bo LUO 1(State Key Laboratory of Systematic and Evolutionary botany,institute of botany,chinese academy of sciences,beijing 100093,china) 2(Graduate University of the chinese academy of sciences,beijing 100049,china) (State Key Laboratory of Systematic and Evolutionary botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Graduate University of the chinese academy of sciences Beijing 100049 China) *Correspondence: Yi-Bo LUO *Correspondence: E-mail: luoyb@*** Tel.: 86-10-62836514 Fax: 86-10-62590843.

Pollination limitation is common in flowering plants and is thought to be a factor driving the evolution of floral *** plasticity of floral longevity to pollination may be an adaptation of plants to pollen ***,this adaptation is less critical in short-lived *** evaluate pollen limitation and the plasticity of floral longevity to pollination in Potentilla tanacetifolia,a gynodioecious herb with short-lived flowers,we analyzed its breeding system,tested sex-differential pollen limitation,and compared variations in floral display size in natural populations in Duolun County,Inner Mongolia,*** pollination experiments and pollinator exclusion treatments revealed that *** is self-compatible and non-autonomously apomictic and shows sex-differential pollen *** plasticity of floral longevity to pollination was observed;the floral duration of female plants was prolonged by approximately 3-4 hours with pollination exclusion ***,the percentage of flowers displayed on female plants during pollination exclusion treatment was significantly higher than that during natural *** natural pollination conditions,the percentage of flowers displayed on female plants was significantly higher than on hermaphrodite ***,approximately 50%of the pollen grains spread out of the anthers of hermaphrodite flowers within 2 h of anthesis;the number of pollen grains adhering to the stigmas of hermaphrodite flowers was significantly higher than that adhering to female flowers when flowers shed their *** results indicate that variation in floral longevity may be an adaptive strategy to pollination conditions for gynodioecious ***.

关键词： floral longevity gynodioecy plasticity pollen limitation Potentilla tanacetifolia.

Value of ecosystem services in china

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chinese Science Bulletin 2000年第10期45卷 870-876页

作者： CHEN Zhongxin & ZHANG XinshiLaboratory of Quantitative Vegetation Ecology, institute of botany, chinese academy of sciences, beijing 100093, china Current address: institute of Natural Resources and Regional Planning, chinese academy of Agricultural sciences, beijing 100081, china Laboratory of Quantitative Vegetation Ecology Institute of Botany Chinese Academy of Sciences Beijing China

The function and services are the important components of the life-support system in theplanet, as well as the basic elements for sustainable development of environment and society. It is a must to evaluate it for incorporating it with the social-economic system. It is also an important approach to draw the public attention on the environmental and ecosystem conservation. In this study, the ecosystem function and services in china were estimated by employing the classification and economic parameters from Costanza et al. The type and area of terrestrial ecosystems were extracted from Vegetation Map of china (1:4 000 000), and then the distribution map of ecosystem services of china was drawn. According to our calculation, the total value of ecosystem services in china is 77 834.48×108 RMB yuan per annum. The value for terrestrial ecosystem is 56 098.46×108 yuan per annum, and that for marine ecosystem is 21 736.02×108 yuan per annum. The value of ecosystem services in china is 1.73 times bigger

关键词： ecosystem function service.

Thermal stability of oxygen evolution in photosystem Ⅱ core complex in the presence of digalactosyl diacylglycerol

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chinese Science Bulletin 2002年第24期47卷 2089-2092页

作者： YANG Zhenle, LI Liangbi & KUANG TingyunPhotosynthesis Research Center, institute of botany, chinese academy of sciences, beijing 100093, china Photosynthesis Research Center Institute of Botany Chinese Academy of Sciences Beijing China

The influence of digalactosyldiacylglycerol (DGDG), one of the photosynthetic membrane lipids, on heat inactivation of the process of oxygen evolution has been studied in vitro in photosystem Ⅱ(PS Ⅱ) core complex. It was found that the temperature of semi-inactivation of oxygen evolution in the complex increased from 40.0 to about 43.0℃ in the presence of DGDG with 5-min heat treatment in the dark. Furthermore, when PS Ⅱ core complex was incubated for 5 min at 45.0℃, the oxygen evolution in the complex was completely lost, whilst the DGDG-complexed PS Ⅱ core complex still retained a 16% of activity (100% for 25.0℃). In addition, a 1-h incubation at 38.0℃ inactivated absolutely the oxygen evolution for the PS Ⅱ core complex. By contrast, there remained about 20% of activity (zero time for 100%) for the complex in the presence of DGDG under the same condition. These results indicate a new role of DGDG in the protection of PS Ⅱ core complex against the deleterious effects of temperature. It was

关键词： digalactosyl diacylglycerol photosystem Ⅱ core complex extrinsic protein of 33 kD thermal stability oxygen evolution.

Terrestrial transect study on driving mechanism of vegetation changes

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Science china Earth sciences 2008年第7期51卷 984-991页

作者： ZHANG YuJin1,2 & ZHOU GuangSheng1 1 State Key Laboratory of Vegetation and Environmental Change, institute of botany, chinese academy of sciences, beijing 100093, china 2 Graduate University of chinese academy of sciences, beijing 100049, china 1. State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China 2. Graduate University of chinese academy of sciences Beijing 100049 China

In terms of chinese climate-vegetation model based on the classification of plant functional types, to- gether with climatic data from 1951 to 1980 and two future climatic scenarios (SRES-A2 and SRES-B2) in china from the highest and the lowest emission scenarios of greenhouse gases, the distribution patterns of vegetation types and their changes along the Northeast china Transect (NECT) and the North-South Transect of Eastern china (NSTEC) were simulated in order to understand the driving mechanisms of vegetation changes under climatic change. The results indicated that the vegetation distribution patterns would change significantly under future climate, and the major factors driving the vegetation changes were water and heat. However, the responses of various vegetation types to the changes in water and heat factors were obviously different. The vegetation changes were more sensi- tive to heat factors than to water factors. Thus, in the future climate warming will significantly affect vegetation distribution patterns.

关键词： driving mechanism vegetation terrestrial transect climatic change plant functional types

Present status and development on biological nitrogen fixation research in china

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chinese Science Bulletin 2003年第10期48卷 954-960页

作者： SHEN Shihua & JING Yuxiang Key Laboratory of Photosynthesis and Plant-Environment MolecularPhysiology, institute of botany, chinese academy of sciences, beijing 100093, china Key Laboratory of Photosynthesis and Plant-Environment Molecular Physiology Institute of Botany Chinese Academy of Sciences Beijing 100093 China

This presentation introduces the advances inbiological nitrogen fixation research abroad, in particular,describes the great progress and achievements on itsresearch in china as follows: collection of rhizobial resources and establishment of the largest database of Rhizobium inchina, correction and development of Rhizobium taxonomy in international; discovery of a couple of nif genes,identification and unification of linkage among the nif gene operons of Klebsiella pneumoniae, finding of regulative mechanism of positive regulation nif gene and its sensitivity to oxygen, temperature; finding of the activity of nodulation gene nodD3 product in Sinorhizobium meliloti which is notcontrolled by flavonoid produced from its host alfalfa;finding of the association between expression of genes coding the products for carbon utilization and nitrogen metabolism and their regulations; chemical synthesis of nodulationfactor of Sinorhizobium meliloti; constructions of engineered nitrogen fixers and utilization in practice based on theresearch of gene expression and regulation; chemicalsimulation of the structure and function of nitrogenase and bringing forward the model of nitrogenase active center for the first time in international and synthesis of modelcompounds which were paid attention by colleagues abroad. Finally, the development of nitrogen fixation research inchina in future has been put forward, suggesting that the nifgene regulation and its role in providing crops with nitrogen element, signal transduction and molecular interactions between Rhizobium and legume, coupling between carbonand nitrogen metabolisms, nitrogen fixation andphotosynthesis, and functional genomics of nitrogen-fixing nodule symbiosis, etc., would be actively worked on.

关键词：现状发展生物固氮技术中国固氮酶基因表达微生物植物相互作用化学模型

Climate controls on dust storm occurrence in Maowusu Desert, Inner Mongolia, North china

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Journal of Environmental sciences 2001年第1期13卷 14-21页

作者： HUANG Fu xiang, GAO Qiong (Laboratory of Quantitative Vegetation Ecology, institute of botany, chinese academy of sciences, beijing 100093, china. E mail: hfx1121@***) Laboratory of Quantitative Vegetation Ecology Institute of Botany Chinese Academy of Sciences Beijing 100093 China. hfx1121@***

Dust storms occurring in arid and semi-arid regions play a main role in the evolution of landscapes. Climate is generally regarded to be important factors influencing the occurrence of dust storm, however, the way of climate controlling dust storms had been poorly understood. In this paper, we present the Eω Index model to describe the relationship between climate variables and dust storm frequency using the available meteorological data from three meteorological stations in Maowusu Desert. This index model explains 83.6%, 69.5% and 65.09% of the variance of dust storm frequency in three regions from the north to the south, respectively and this difference is probably caused by the difference of the human disturbance. The Eω Index model is an effective predictor of dust storm frequency and provides us a quite good understanding on the occurrence of dust storms in Maowusu Desert.

关键词： Arid regions Dust Meteorology

Genetic differentiation of Wolffia globosa in china

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Journal of Systematics and Evolution 2011年第6期49卷 509-517页

作者： 1,2Jun-Xia YUAN 1Jin PAN 1Bao-Sheng WANG 1Da-Ming ZHANG 1(State Key Laboratory of Systematic and Evolutionary botany,institute of botany,chinese academy of sciences,beijing 100093,china) 2(Graduate University of chinese academy of sciences,beijing 100049,china) (State Key Laboratory of Systematic and Evolutionary botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Graduate University of chinese academy of sciences Beijing 100049 China) *Correspondence: Da-Ming ZHANG *Correspondence: E-mail: zhangdm@*** Tel.: 86-10-62836492 Fax: 86-10-62590843.

Wolffia Horkel ex Schleid.(Lemnaceae) includes the world’s smallest ***,their bodies are extremely simplified,making classification difficult and *** reports about the genetic structure of these clonal-dominant aquatic plants have been published until *** this study,of 247 samples from 42 populations spanning representative locations in china,two chloroplast haplotypes(glo-cp and un-cp) and 66 amplified fragment length polymorphism genotypes were *** on wide sampling,cpDNA haplotypes,and amplified fragment length polymorphism profiles,we found that there are two genetic lineages(glo-and unlineages) of Wolffia species in *** and genetic diversity of Wolffia species are high compared with other clonal plants(Simpson’s index,D = 0.97;Nei’s diversity,H = 0.1835).Different spatial structure patterns were detected between glo-and *** autocorrelation at short distances(1500 km) were detected within the glo-lineage,but no significant spatial genetic structure was detected beyond 100 km within the ***,spatial genetic analysis of *** revealed significant autocorrelation within short distances,indicating that restricted gene flow might be one of the most important factors in shaping genetic structure.

关键词： AFLP chloroplast DNA genetic differentiation spatial genetic structure Wolffia.

New insights into the species problem

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Science china(Life sciences) 2010年第8期53卷 964-972页

作者： YANG Yong1 & ZHOU ZheKun2 1State Key Laboratory of Systematic and Evolutionary botany, institute of botany, chinese academy of sciences, beijing 100093, china 2Key Laboratory of Biodiversity and Biogeography, Kunming institute of botany, chinese academy of sciences, Kunming 650204, china 1. State Key Laboratory of Systematic and Evolutionary botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China2. Key Laboratory of Biodiversity and Biogeography Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China

Historical opinions of the "species problem" are briefly reviewed, and four salient stages are recognized according to origin of species concepts. We propose that species is the unit preserving superior gene assembly and is maintained by specific mechanisms. Based on characteristics of plant evolution, we assume that understanding plant species may include three stages, i.e. morphological recognition stage, multidisciplinary verification stage, and illuminating mechanisms preserving superior gene assembly.

关键词： species concept plant evolution phylogeny

Toward a general evaluation model for soil respiration (GEMSR)

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Science china(Life sciences) 2008年第3期51卷 254-262页

作者： ZHOU GuangSheng, JIA BingRui, HAN GuangXuan & ZHOU Li Key Laboratory of Vegetation and Environmental Change, institute of botany, chinese academy of sciences, beijing 100093, china Key Laboratory of Vegetation Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China

Soil respiration is an important component of terrestrial carbon budget. Its accurate evaluation is es- sential to the study of terrestrial carbon source/sink. Studies on soil respiration at present mostly focus on the temporal variations and the controlling factors of soil respiration, but its spatial variations and controlling factors draw less attention. Moreover, the evaluation models for soil respiration at present include only the effects of water and heat factors, while the biological and soil factors controlling soil respiration and their interactions with water and heat factors have not been considered yet. These models are not able to accurately evaluate soil respiration in different vegetation/terrestrial ecosystems at different temporal and spatial scales. Thus, a general evaluation model for soil respiration (GEMSR) including the interacting meteorological (water and heat factors), soil nutrient and biological factors is suggested in this paper, and the basic procedure developing GEMSR and the research tasks of soil respiration in the future are also discussed.

关键词： soil respiration controlling factors general evaluation model