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Clonal Integration of Fragaria orientalis in Reciprocal and Coincident Patchiness Resources: Cost-Benefit Analysis  [PDF]
Yunchun Zhang, Qiaoying Zhang
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0080623
Abstract: Clonal growth allows plants to spread horizontally and to experience different levels of resources. If ramets remain physiologically integrated, clonal plants can reciprocally translocate resources between ramets in heterogeneous environments. But little is known about the interaction between benefits of clonal integration and patterns of resource heterogeneity in different patches, i.e., coincident patchiness or reciprocal patchiness. We hypothesized that clonal integration will show different effects on ramets in different patches and more benefit to ramets under reciprocal patchiness than to those under coincident patchiness, as well as that the benefit from clonal integration is affected by the position of proximal and distal ramets under reciprocal or coincident patchiness. A pot experiment was conducted with clonal fragments consisting of two interconnected ramets (proximal and distal ramet) of Fragaria orientalis. In the experiment, proximal and distal ramets were grown in high or low availability of resources, i.e., light and water. Resource limitation was applied either simultaneously to both ramets of a clonal fragment (coincident resource limitation) or separately to different ramets of the same clonal fragment (reciprocal resource limitation). Half of the clonal fragments were connected while the other half were severed. From the experiment, clonal fragments growing under coincident resource limitation accumulated more biomass than those under reciprocal resource limitation. Based on a cost-benefit analysis, the support from proximal ramets to distal ramets was stronger than that from distal ramets to proximal ramets. Through division of labour, clonal fragments of F. orientalis benefited more in reciprocal patchiness than in coincident patchiness. While considering biomass accumulation and ramets production, coincident patchiness were more favourable to clonal plant F. orientalis.
The characteristics of stoloniferous herb Fragaria vesca L. ramet population and their variation along an altitudinal gradient in the eastern edge of the Qing-Zang Plateau in China

Chen Jinsong,DONG Ming,YU Dan,

生态学报 , 2003,
Abstract: Stoloniferous herb Fragaria vesca was sampled in the unshading (open fields) and the shading conditions (forest undergrowth) at the five different altitudes (2426m, 2750m, 3200m, 3484m and 3944m) in the eastern edge of Qing-Zang Platea u in China in order to investigate the characteristics of its ramet population a nd their variation along the altitudinal gradient. The resul ts show that its ramet population density decreased with increase of altitude, b oth under the unshading and the shading conditions. Under unshading conditions, its ramet population density was significantly higher than that under shading co nditions. The interaction of elevation by light was significant with respect to ramet population density. Under unshading conditions, its ratio of root to shoo t varied quadratically with increase of elevation. Under shading conditions, its ratio of root to shoot was smallest at 2426m above sea level than those at the other four altitudes. There was not significant effect of the light condition on the ratio of root to shoot. The distribution pattern of Fragaria vesca rame t po pulation at 3484m above sea level and 3944m above sea level was investigated by using spatial auto-correlation analysis (Moran`I). The results show that the ra met population of Fragaria vesca had non-random distribution pattern at mul tipl e scales and the most frequently observed pattern was contagious at the scale of d=1(0.2m). The maximum size of ramet cluster was bigger at 3944m above sea level than that at 3484m above sea level. Finally, the results were discussed i n the context of adaptation of clonal plants to environments.
Fine-cale clonal structure of the stoloniferous herb Duchesnea indica

LI Jun-Min,JIN Ze-Xin,

生态学报 , 2009,
Abstract: Genetic diversity, clonal diversity and clonal structure within the patches of the stoloniferous herb Duchesnea indica Focke were analyzed using inter-simple sequence repeat (ISSR) techniques. The relationship between clonal structure and habitat conditions was also studied to elucidate how clonal structure of D. indica was established. Genetic diversity of D. indica was relatively low: percentage of polymorphic loci (P) 37.93%, Shannon informative index (I) 0.2402, and Nei′s gene index (h) 0.1677. Clonal diversity of D. indica was similar to that of other clonal plant species. The proportion of distinguishable genotypes (G/N) was 0.2013, Simpson′s diversity index (D) 0.6396 and genotypic evenness (E) 0.5862. Both genetic diversity and clonal diversity of D. indica were the highest within the patch in Linhai City (LH), lowest within the patch in Tiantai City (TT), and intermediate within the patch in Anju City (AJ). Dominant clones were found in all three patches, but their size was the largest in the TT path, smallest in the LH patch and intermediate in the AJ patch. Spatial autocorrelation analysis showed that in the LH patch the autocorrelation coefficient was significantly positive at distances of 20 cm and 40 cm with an X-intercept of 49.959. In the AJ patch the correlation value was significantly positive at 20 cm with an x-intercept of 63.333 and in the TT patch it is positive and significant at 20 cm, 30 cm, 40 cm and 70 cm, respectively, with an X-intercept of 90.512. This indicates that the spatial autocorrelation scale of the genotype was highest within the TT patch, lowest in the AJ patch, and that the average length of genetic patches was the largest in the TT patch and smallest in the LH patch. The genetic diversity, clonal diversity and clonal structure of D. indica in three different patches were significantly different, which might be due to vegetative spreading and also the low seed germination rate. The ecological factors, together with others such as disturbance, succession and mutation, might have played important roles in the formation of the genetic structure, clonal structure and spatial distribution patterns.
Plasticity of clonal architecture in response to soil nutrients in the stoloniferous herb Duchesnea indica Focke

LUO Xue-Gang,

生态学报 , 2001,
Abstract: Architectural plasticity of clonal plants may modify their ways of utilization of soil nutrients in their habitats of resource heterogeneity, and therefore be ecologically important. The plasticity of clonal architecture, in terms of space length, branch intensity and branch angle, in response to soil nutrients in the stoloniferous herb, Mock-strawberry (Duchesnea indica Focke), was investigated using the method of experimental ecology. The experimental plant materials were collected from Chinese subtropic...
Plant diversity and interspecific relationship of main herb species in Platycladus orientalis plantation in Jiufeng Mountain, Beijing

- , 2017,
Abstract: 【目的】对北京鹫峰地区侧柏人工林草本层群落物种多样性及种间关系进行研究,以更好地认识该地区侧柏林草本层物种组成、结构、功能及与环境的关系。【方法】基于50个侧柏样方的调查数据,运用Simpson指数、Shannon Weiner指数、Pielou指数和Gini指数4个多样性指数进行物种多样性计算,利用方差比率(VR)法,并结合以χ2检验为基础的联结系数AC和共同出现百分率PC等方法,对主要物种种间的联结性进行测度。【结果】侧柏人工林草本层物种均匀度指数较大,Pielou、Gini指数分别为0.809和0.807,而物种多样性指数偏小,Simpson、Shannon Weiner指数分别为0.591和1.137; VR为1.826,草本层主要种群间整体上表现出净的正关联;在草本层的28个种对中,有10个种对达到显著联结(3.841≤χ2<6.635),其中有3个种对达到极显著关联(χ2≥6.635),且在显著关联种对中,显著正关联的有70%,表明该草本层群落中主要物种处于稳定阶段;狗尾巴草(Setaria viridis)与牵牛花(Pharbitis nil)表现出极显著正联结,而(Oplismenus undulatifolius)、披针叶苔草(Carex lanceolata)表现出极显著负联结; AC值和PC值的计算结果与χ2统计量结果基本一致,为了能够更加准确地分析种对的关联程度,在以χ2检验为基础的同时,结合联结系数AC和共同出现百分率PC等方法测度物种种间的联结性更有说服力。【结论】北京鹫峰地区侧柏人工林草本层主要物种的关联性在整体上表现出净的正关联,说明该群落在向着顶极群落发展,群落结构及种类趋于完善和稳定,种间关系也趋于正关联,以实现物种间的稳定共存。
【Objective】The plant diversity and interspecific relationship of main herb species in Platycladus orientalis plantation in Jiufeng Mountain were analyzed to better understand the community composition,structure,function and environment relationship of herb layer in P.orientalis plantation forest. 【Method】Based on the data at 50 quadrats in P.orientalis plantation,Simpson index,Shannon-Weiner index,Pielou index and Gini index were used to investigate the species diversity of herb layer in P.orientalis plantation in Jiufeng Mountain.The correlation among the species was analyzed using variance ratio (VR),as well as 2 test based coefficient (AC) and percentage of co occurrence (PC).【Result】In herb layer of P.orientalis plantation in Jiufeng Mountain,Beijing,the species evenness index was large,the Pielou index was 0.809,the Gini index was 0.807,the species diversity index was small,the Simpson index was 0.591,and the Shannon-Weiner index was 1.137.The VR was 1.826,and main species in the herbaceous layer showed positive correlation.Among the 28 specie pairs in herbaceous layer,there were 10 pairs with significant relationship (3.841≤χ2<6.635),and 3 pairs with extremely significant correlation(χ2≥6.635).Among significantly correlated pairs,70% showed positive correlation,indicating that the dominant species in herbaceous layer were stable.Significant positive correlation was found between S.viridis and Pharbitis nil,and significant negative correlation was found between S.viridis and Oplismenus undulatifolius,S.viridisand Carex lanceolata.The AC and PC results were consistent with χ2 statistic results.Combing χ2 test,AC and PC would be more convening in measuring relationship. 【Conclusion】The interspecific relationships of main herb species in P.orientalis plantation of Jiufeng Mountain were
Effects of clonal integration on growth of stoloniferous herb Centella asiatica suffering from heterogeneous heavy metal Cd~(2+) stress

LIU Fu-Jun,LI Yun-Xiang,LIAO Yong-Mei,CHEN Jin-Song,QUAN Qiu-Mei,GONG Xin-Yue,

植物生态学报 , 2011,
Abstract: Aims A pot experiment to examine the effects of clonal integration on growth of the stoloniferous herb Centella asiatica suffering from heterogeneous heavy metal Cd2+ stress was conducted to address two questions: (1) does clonal integration alleviate the negative effects on growth of clonal plants suffering from heterogeneous heavy metal stress; and (2) do the ramets growing in unfavorable microhabitats incur increased photosynthetic efficiency in the connected ramets? Methods Relatively young, distal ramets of C. asiatica were assigned to normal or Cd2+ stressed soil, and the stolon connections between the relatively old proximal ramets and the young distal ramets were either severed or left intact. The net photosynthetic rate (Pn), chlorophyll fluorescence (maximum quantum yield of PSII, Fv/Fm) and chlorophyll contents of distal ramets and Pn of proximal ramets were measured. The growth performance of distal and proximal ramets was investigated at the end of the experiment. Important findings Cd2+ stress treatment significantly decreased the Pn, Fv/Fm, chlorophyll contents and growth of distal ramets. Clonal integration significantly alleviated the negative effect of Cd2+ stress to distal ramets in terms of Pn, Fv/Fm, chlorophyll contents and biomass of distal ramets. There was no significant cost to the connected proximal ramets, and clonal integration did not incur increased photosynthetic efficiency in the proximal ramets. In addition, clonal integration significantly decreased root to shoot ratio of distal ramets suffering from Cd2+ stress, and reduced the uptake of the heavy metal. Petiole length of proximal and distal ramets was not significantly affected by stolon severing and Cd2+ stress. It is suggested that clonal integration may enhance growth of clonal plants suffering from heterogeneous heavy metal stress.
Seed size effect on seedling growth under different light conditions in the clonal herb Ligularia virgaurea in Qinghai Tibet Plateau

HE Yan-Long,WANG Man-Tang,DU Guo-Zhen,

生态学报 , 2007,
Abstract: We studied the influence of seed size on germination, seedling growth, and seedling responses to light in Ligularia virgaurea, a clonal herb native to the Qinghai Tibet Plateau. (1) Under unshaded conditions, large seeds had significantly (p<0.01) higher rates of germination than did small seeds. Both large and small seeds showed significantly reduced levels of germination under shaded (by shadecloth) conditions. The magnitude of this effect was greater for small seeds than for large seeds. Germination of small seeds (1.75 mg) was reduced by one eighth, while germination of large (2.80mg) seeds was only reduced by one eleventh. (2) Seedlings from large seeds had significantly higher rates of biomass accumulation (g d-1)than did seedlings from small seeds. This, combined with larger initial masses gave seedlings from large seeds significantly greater total biomass after 60 days of growth. Seedlings from large and small seeds also differed in biomass allocation. After 60 days of growth (under both shaded and unshaded conditions), seedlings from larger seeds had proportionally larger root mass and proportionally smaller leaf mass than did seedlings from small seeds. (3) Seedlings from small seeds have higher relative growth rates (RGR; g g-1 d-1) than do seedlings from large seeds, under both shaded and unshaded conditions. By contrast, there was no significant difference between leaf area ratio (LAR); specific leaf area (SLA) or leaf weight ratio (LWR) between seedlings from small vs large seeds. RGR, LAR, SLA and LWR were all significantly higher in seedlings grown under shaded conditions than in seedlings grown in full light.
Biological Properties of Thuja Orientalis Linn
Advances in Life Sciences , 2012, DOI: 10.5923/j.als.20120202.04
Abstract: Thuja orientalis (Commonly- Morpankhi, Family- Cupressaceae) is an evergreen, monoecious trees or shrubs used in various forms of traditional medicines and homeopathy in various ways. In traditional practices Thuja is used for treatment of bronchial catarrh, enuresis, cystitis, psoriasis, uterine carcinomas, amenorrhea and rheumatism. Recent researches in different parts of the world have shown that T. orientalis and its active component thujone have the great potential against a various health problems. T. orientalis preparations can be efficiently used against microbial/worm infection. It can be used as antioxidant, anticancer and anti-inflammatory agent. Instead of these effects, it can be also used as insecticidal, molluscicidal and nematicidal activity against different pests. The present review highlights the some important biological properties of T. orientalis.
Clonal growth of stoloniferous herb Potentilla anserina on degraded and non-degraded alpine meadow soil

SHEN Zhenxi,CHEN Zuozhong,WANG Yanhui,ZHANG Jingli,ZHOU Huakun,

应用生态学报 , 2003,
Abstract: The clonal growth of Potentilla anserina on degraded and non degraded Kobresia humilis meadow soil was studied by a transplanting experiment in the field. No significant differences in numbers of stolons, height, and leave size per mother ramet were observed between the two soils , but the numbers of leaves per mother ramet, length and width of stolon,and spacer length were significantly different. There were more leaves per mother ramet, longer stolon and spacer, and wider stolon on degraded soil, where available nutrient was poor than in non degraded soil. Under degraded alpine meadow soil condition, the clonal plant species might produce much more photosynthetic product to support stolon growth by the increase of leave numbers per mother ramet,and the longer and wider stolon could intensify the foraging ability of the mother ramet that would benefit to daughter ramet. Both mother and daughter ramet of Potentilla anserina invested much more biomass to their underground part (root system) in non degraded soil to increase the survival rate of daughter ramet.
Ramets and Genets in the Tillering Clonal Herb Panicum miliaceum in Hierarchical Response to Heterogeneous Nutrient Environments

HE Weiming,DONG Ming,

生态学报 , 2002,
Abstract: Panicum miliaceum is a tillering clonal species with profuse roots, and is widespread in northern China. The species has been regarded as an ideal plant for experiments with nutrient patches due to its rapid growth. Early June 1999, plastic boxes (18cm×18cm ×30cm) were put at the center of paper boxes (42cm×35cm×30cm), and the plastic boxes and the space between the plastic boxes and the paper boxes were fully filled with a mixture of sand and compound fertilizer in various proportions. Each growth containe...
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