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Stand dynamics of the drought-affected floodplain forests of Araguaia River,Brazilian Amazon

Forest Ecosystems 2017年第3期4卷 201-210页

作者： Jürgen Homeier Dariusz Kurzatkowski Christoph Leuschner plant ecology Albrecht von Haller Institute for Plant Sciences University of Goettingen

Background： The floodplain forests of Araguaia River, a clear-water river in the southeastern Amazon（Tocantins State, Brazil）, are characterized by seasonal flooding up to 3.5 m height, low nutrient levels in the water, and seasonal drought periods of 4–5 ***： We studied the forest dynamics（tree diameter growth, tree mortality and recruitment） of this unique forest ecosystem over a 5-year period by repeated censuses in 12 permanent plots established along a flooding ***： The cumulative basal area in the plots increased by 0.84（±0.45） m^2·ha^-1·yr^-1（mean ±SD） in the annual y-flooded（AF） plots in lower terrain and by 0.69（±1.00） m^2·ha^-1·yr^-1 in the higher non-annual y flooded（NAF） plots, corresponding to an aboveground biomass increase of 0.81（±0.57） and 0.69（±1.58） Mg·ha^-1·yr^-1 in the AF and NAF plots, indicating a recent carbon sink in the biomass. Mean diameter growth rate was 1.8（±0.44） mm·yr^-1 in the AF and 2.0（±0.56） mm·yr^-1 in the NAF plots（corresponding to a coarse wood production of 1.53（±1.29） and 2.02（±0.52） Mg·ha^-1·yr^-1）,indicating no flooding effect on radial growth. Mean mortality rates in the 5-year period were 1.9（±0.37）·yr^-1 in the AF plots and 1.8（±0.87）%·yr^-1 in the NAF plots with no differences along the flooding gradient. Highest mortalities were registered in the AF plots for the 10–20 cm dbh class（2.4%·yr^-1）, likely as a consequence of flooding,and in the NAF plots for the 40–50 cm dbh class（3.0%·yr^-1）, probably mainly caused by ENSO-related ***： We conclude that these drought-affected tropical floodplain forests have a lower standing biomass and aboveground productivity than central Amazonian floodplain forests in more humid climates, and the imprint of the flooding gradient on stand dynamics is relatively weak, which may result from the lower flooding height and the interaction of flooding with low nutrient supply and periodic drought.

关键词： Amazon Diameter growth Dry season Flooding regime Mortality rate Productivity Tree recruitment

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Vegetation-environment relationship in Pinus wallichiana forests of the Swat Hindukush range of Pakistan

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Journal of Forestry Research 2020年第1期31卷 185-195页

作者： Inayat Ur Rahman Nasrullah Khan Kishwar Ali Siraj Ahmad laboratory of plant ecology and Dendrochronology Department of BotanyUniversity of Malakand

Understanding the influence of environmental variables on the spatial distribution of ecological communities is essential to predict the response of vegetation to various environmental *** theory suggests that multiple environmental factors shape local species assemblages and should influence the various components of community structure and composition in different *** study aimed to classify Pinus wallichiana dominated forests in the Swat Hindukush range mountains to understand the relative influence of multiple environmental filters on its composition and *** forests represent the most typical of the species distribution in northern Pakistan and were not subjected to any phytosociological *** this purpose,thirty forest stands,spanning a wide range of physical habitats were sampled using 10 x 10 m plots and the importance value index was *** floristic and environmental data were subjected to Ward’s agglomerative cluster analysis for objective classification and ordinated with NMS ordination for pattern description and testing the vegetation-environmental *** floristically and ecologically distinct communities were recognized along the topographic gradient(elevation,r=0.377;slope,r=0.5548) coupled with soil physical(clay,r=0.2782;silt,r=0.3225) and chemical properties(pH,r=0.4975;lime,r=3982).An elevation gradient of 100 m separated the low(Pinus wallichiana-Quercus dilatata community)and middle elevations forest stands(*** pure population) from the highland population type(Pinus wallichiana-Cedrus deodara community).The floristics and structure of these forest types respond directly or indirectly to topographic and soil variables which were evidenced from the floristic composition,species richness,and community *** characteristics of the communities changed from heterogenous,dense stands to sparsely dispersed conifers,broadleaved-evergreen,and deciduous vegetation types along

关键词： Blue pine forests Classification-ordination Ecological gradient Hindukush range mountains Species composition

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Variation and heritability of morphological and physiological traits among Leymus chinensis genotypes under different environmental conditions

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Journal of Arid Land 2019年第1期11卷 66-74页

作者： YANG Xue LI Junpeng ZHAO Tingting MO Lidong ZHANG Jianli REN Huiqin ZHAO Nianxi GAO Yubao Department of plant Biology and ecology College of Life Science Nankai University

Intraspecific trait variation and heritability in different environmental conditions not only suggest a potential for an evolutionary response but also have important ecological consequences at the population, community, and ecosystem levels. However, the contribution of quantitative trait variation within a grassland species to evolutionary responses or ecological consequences is seldom documented. Leymus chinensis is an important dominant species in semi-arid grasslands of China, which has seriously suffered from drought and high temperature stresses in recent decades. In the present study, we measured variation and heritability of 10 quantitative traits, namely the number of tillers, maximum shoot height, number of rhizomes, maximum rhizome length, rhizome mass, aboveground mass, root mass, maximum net photosynthetic rate(Pmax), specific leaf area(SLA), and leaf length to leaf width ratio(LL/LW), for 10 genotypes of L. chinensis under one non-stress(Ck) condition and three environmental stress conditions(i.e., drought(Dr), high temperature(Ht), and both drought and high temperature(DrHt)). Result indicated that(1) the interaction of genotype and environmental condition(G×E) was significant for 6 traits but not significant for the other 4 traits as shown by two-way analysis of variance(ANOVA), suggesting that different selection forces were placed for different traits on the factors dominating phenotypic responses to different environmental conditions. Moreover, these significant G×E effects on traits indicated significantly different phenotypic adaptive responses among L. chinensis genotypes to different environmental conditions. Additionally, individuals could be grouped according to environmental condition rather than genotype as shown by canonical discriminant analysis, indicating that environmental condition played a more important role in affecting phenotypic variation than genotype;(2) by one-way ANOVA, significant differences among L. chinensis genotypes w

关键词： Leymus chinensis genotype quantitative trait variation heritability drought high temperature

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Cortical Microtubule Reorientation and Its Relation to Cell Surface Texture of Epidermal Cells of Arabidopsis Thaliana Hypocotyls under Simulated Microgravity Conditions

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空间科学学报 2019年第4期39卷 478-488页

作者： XIE Junyan ZHANG Yue ZHENG Huiqiong Center for Excellence in Molecular plant Sciences Institute of Plant Physiology and EcologyChinese Academy of Sciences

Gravitropic curvature growth of Arabidopsis hypocotyls mainly occurred in the rapid growing Elongation Zone(EZI),not in the slow-growing Elongation Zone(EZII).By examining reorientation of Microtubules(MT)and phenotype of the cell wall in the EZI and the EZII of Arabidopsis hypocotyls under normal gravitational condition,it is found that MTs in the rapid growing epidermal cells were mainly in the transverse direction,while those in the non-growing epidermal cells were in the longitudinal ***,this difference in cortical MT arrays between the EZI and EZII cells disappeared when the seedlings were exposed to the simulated microgravity condition on a horizontal *** emission scanning electron microscopy revealed that the surface texture of epidermal cells,like the direction of the MT,in the EZI and the EZII also became similar when exposed to the simulated microgravity *** result indicated that simulate microgravity could modify the potential differentiation between the EZI and the EZII by affecting the orientation of cortical MT in the epidermal cells.

关键词： Arabidopsis Cortical microtubule Cell surface texture Hypocotyls Simulated microgravity

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Genetic Improvement of Willow for Bioenergy and Biofuels

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Journal of Integrative plant Biology 2011年第2期53卷 151-165页

作者： Angela Karp Steve J.Hanley Sviatlana O.Trybush William Macalpine Ian Shield Centre for Bioenergy and Climate Change Plant and Invertebrate Ecology DepartmentRothamsted Research

Willows （Salix spp.） are a very diverse group of catkin-bearing trees and shrubs that are widely distributed across temperate regions of the globe. Some species respond well to being grown in short rotation coppice （SRC） cycles, which are much shorter than conventional forestry. Cop- picing reinvigorates growth and the biomass rapidly accumulated can be used as a source of renewable carbon for bioenergy and biofuels. As SRC willows re-distribute nutrients during the perennial cycle they require only minimal nitrogen fertilizer for growth. This results in fuel chains with potentially high greenhouse gas reductions. To exploit their potential for renewable energy, willows need to be kept free of pests and diseases and yields need to be improved without significantly increasing the requirements for fertilizers and water. The biomass composition needs to be optimized for different end-uses. Yields also need to be sustainable on land less productive for food crops to reduce conflicts over land use. Advances in understanding the physiology and growth of willow, and in the identification of genes underlying key traits, are now at the stage where they can start to be used in breeding programs to help achieve these goals.

关键词： Genetic Improvement of Willow for Bioenergy and Biofuels QTLs SRC

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Antihyperglycemic and antioxidant activities of total alkaloids from Catharanthus roseus in streptozotocin-induced diabetic rats

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Journal of Forestry Research 2016年第1期27卷 167-174页

作者： Lin Zhang Gang Wei Yang Liu Yuangang Zu Qinghui Gai Lei Yang Key laboratory of Forest plant ecology Ministry of Education Northeast Forestry University

We evaluated the hypoglycemic and antioxi- dant effects of the total alkaloids of leaves and twigs of Catharanthus roseus Linn. （CTA） in streptozotocin （STZ）- induced diabetic rats. The hypoglycemic effect was mea- sured by blood glucose and plasma insulin level. Oxidative stress was measured in heart, liver and kidney by levels of antioxidant markers, free radical scavengers and lipid peroxides i.e. superoxide dismutase （SOD）, catalase （CAT）, glutathione （GSH） and thiobarbituric acid reactive substances （TBARS）. Biochemical parameters, i.e. aspar- tate aminotransferase （AST）, alanine aminotransferase （ALT）, alkaline phosphate （ALP） were observed in diabetic control and treated rats. Oral administration of CTA for 30 days was followed by a significant （P 〈 0.05） decrease in fasting blood glucose and increase in insulin level as compared with untreated diabetic rats. Also it significantly （P 〈 0.05） reduced ALT, AST and ALP. The treatment also resulted in significant （P 〈 0.05） reductions in GSH, SOD, CAT, and decrease in TBARS in the heart, liver and kidney of diabetic rats. The results suggest that CTA can effectively normalize the impaired antioxidant status in STZ-induced diabetes in a dose-dependent *** exerted rapid protective effects against lipid peroxi- dation by scavenging of free radicals and reducing the risk of diabetic complications.

关键词： Antihyperglycemic activity Antioxidantactivity Catharanthus roseus Streptozotocin-induceddiabetic rats Total alkaloids

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Success of three soil restoration techniques on seedling survival and growth of three plant species in the Sahel of Burkina Faso(West Africa)

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Journal of Forestry Research 2016年第2期27卷 313-320页

作者： Philippe Bayen Anne Mette Lykke Adjima Thiombiano laboratory of plant Biology and ecology University of Ouagadougou Department of Bioscience Aarhus University

In the Sahel of Africa, where 90 % of the population depends on natural resources for their liveli- hood, a large part of the soils are structurally unstable, prone to crusting and hard setting, and have low water holding capacity, which hamper vegetation establishment. The effect of soil restoration techniques on survival and growth of seedlings of Acacia nilotica, Acacia tortilis and Jatropha curcas was tested in completely barren, degraded land in a Sahelian ecosystem in Burkina Faso. A total of 522 seedlings （174 plants of each plant species） were planted in a randomized complete block design with three replicates combining three soil preparation techniques： half-moon, zai＂ and standard plantation. Survival and growth rates evaluated over 20 months were significantly higher using the half-moon technique compared with the other two techniques. Survival rates of plant species planted using half-moon technique were 62.5, 28.57 and 10.71% for A. nilotica, A. tortilis and J. curcas respec- tively, but in za＇i and standard planting, seedling survival was zero. The low survival rate of J. curcas using the half-moon technique may indicate that J. curcas is unsuit- able for barren and degraded land, whereas A. nilotica and A. tortilis appear to be promising tree species for rehabil- itation of degraded land.

关键词： Afforestation Bare soil Soil rehabilitation Species selection Water conservation

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CRISPR Primer Designer:Design primers for knockout and chromosome imaging CRISPR-Cas system

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Journal of Integrative plant Biology 2015年第7期57卷 613-617页

作者： Meng Yan Shi-Rong Zhou Hong-Wei Xue National Key laboratory of plant Molecular Genetics Shanghai Institute of Plant Physiology and Ecologythe Chinese Academy of Sciences

The clustered regularly interspaced short palin- dromic repeats （CRiSPR）-associated system enables biologists to edit genomes precisely and provides a powerful tool for perturbing endogenous gene regulation, modulation of epigenetic markers, and genome architecture. However, there are concerns about the specificity of the system, especially the usages of knocking out a gene. Previous designing tools either were mostly built-in websites or ran as command-line programs, and none of them ran locally and acquired a user- friendly interface. In addition, with the development of CRISPR-derived systems, such as chromosome imaging, there were still no tools helping users to generate specific end-user spacers. We herein present researchers to design primers CRISPR Primer Designer for for CRISPR applications. Theprogram has a user-frfendly interface, can analyze the BLAST results by using multiple parameters, score for each candidate spacer, and generate the primers when using a certain plasmid. In addition, CRISPR Primer Designer runs locally and can be used to search spacer clusters, and exports primers for the CRiSPR-Cas system-based chromosome imaging system.

关键词： Chromosome imaging CRISPR knockout primer software

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Regulation of Flowering Time by MicroRNAs

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Journal of Genetics and Genomics 2013年第5期40卷 211-215页

作者： Chuan-Miao Zhou Jia-Wei Wang National Key laboratory of plant Molecular Genetics Institute of Plant Physiology and EcologyShanghai Institutes for Biological Sciences

The shoot apical meristem（SAM） continuously produces lateral organs in *** on the identity of the lateral organs,the life cycle of a plant can be divided into two phases： vegetative and *** SAM produces leaves during the vegetative phase,whereas it gives rise to flowers in the reproductive phase（reviewed in Poethig,2003）.The floral transition,namely the switch from vegetative to reproductive growth,

关键词： Regulation of Flowering Time by MicroRNAs FLC GA

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Genes and speciation: is it time to abandon the biological species concept?

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National Science Review 2020年第8期7卷 1387-1397页

作者： Xinfeng Wang Ziwen He Suhua Shi Chung-I Wu State Key laboratory of Biocontrol Guangdong Key Lab of Plant Resources School of Life Sciences Sun Yat-Sen University Department of ecology and Evolution University of Chicago

The biological species concept(BSC) is the cornerstone of neo-Darwinian thinking. In BSC, species do not exchange genes either during or after speciation. However, as gene flow during speciation is increasingly being reported in a substantial literature, it seems time to reassess the revered, but often doubted, *** to the common perception, BSC should expect substantial gene flow at the onset of speciation, not least because geographical isolation develops gradually. Although BSC does not stipulate how speciation begins, it does require a sustained period of isolation for speciation to complete its course. Evidence against BSC must demonstrate that the observed gene flow does not merely occur at the onset of speciation but continues until its completion. Importantly, recent genomic analyses cannot reject this more realistic version of BSC, although future analyses may still prove it wrong. The ultimate acceptance or rejection of BSC is not merely about a historical debate; rather, it is about the fundamental nature of species – are species(and, hence, divergent adaptations) driven by a relatively small number of genes, or by thousands of them? Many levels of biology, ranging from taxonomy to biodiversity, depend on this resolution.

关键词： speciation species concept gene flow geographical isolation allopatry

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