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夏秋萝卜品比试验
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作者 徐跃进 钟波 李邱 《长江蔬菜》 1999年第3期30-31,共2页
关键词 萝卜 品种 产量产值 植物学性
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Analysis on the Main Botanical Characters of 41 Cucurbita moschata Varieties 被引量:1
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作者 韩小霞 胡新军 +2 位作者 粟建文 袁祖华 李勇奇 《Agricultural Science & Technology》 CAS 2015年第9期1891-1896,共6页
In order to scientifically evaluate the values of Cucurbita moschata cultivars, main botanical characters including the initial flowering date, the first fruiting node, fruit length, fruit stem length, stem diameter, ... In order to scientifically evaluate the values of Cucurbita moschata cultivars, main botanical characters including the initial flowering date, the first fruiting node, fruit length, fruit stem length, stem diameter, internode length, the transverse and longitudinal diameters of the largest leaf, single fruit weight, flesh thickness and soluble solid content of 41 cultivars were measured for conducting diversity, correlation and cluster analysis. The results revealed that the pumpkin cultivars showed large variations in fruit stem length, single fruit weight, fruit length and flesh thickness, but small variations in initial flowering date. Significant, even highly significant correlations were found among the tested traits. Cluster analysis demonstrated that the 41 old Cucurbita moschata cultivars were divided into three groups, of which multiple traits of Group 1 were better than those in the other two groups. High similarities existed in three groups and the cultivars in each group. This research provided basis for selecting excellent traits and parents for the breeding of hybrids. 展开更多
关键词 Cucurbita moschata Botanical character Diversity analysis Cluster analysis
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邻苗柚的特征与丰产栽培技术
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作者 秦光成 陈克明 +2 位作者 刘达明 刘凤璋 秦定荣 《西南园艺》 1998年第4期15-15,共1页
邻苗柚又称长滩柚,系我县从长滩乡柚实生变异中选出的薄皮、无核或少核、肉色鲜红、风味浓郁的优良品系.
关键词 邻苗柚 植物学性 生物学特 丰产 栽培技术
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Current progress and future prospects in phylofloristics 被引量:8
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作者 Rong Li Lishen Qian Hang Sun 《Plant Diversity》 SCIE CAS CSCD 2018年第4期141-146,共6页
The species composition of regional plant assemblages can in large part be explained by a long history of biogeographical and evolutionary events. Traditional attempts of floristic studies typically focus on the analy... The species composition of regional plant assemblages can in large part be explained by a long history of biogeographical and evolutionary events. Traditional attempts of floristic studies typically focus on the analyses of taxonomic composition, often ignoring the rich context that evolutionary history can provide. In 2014, Swenson and Umafia introduced the term 'phylofloristics' to define a phylogenetically enabled analysis of the species composition of regional floras. Integrating phylogenetic information into tradi- tional floristic analysis can provide a promising way to explore the ecological, biogeographic, and evolutionary processes that drive plant assemblies at multiple spatial scales. In this review, we sum- marize the current progress on the phylogenetic structure, spatial phylogenetic pattern, origin and diversification, phylogenetic regionalization of fioristic assemblages, and application of phylogenetic information in biodiversity conservation. These summaries highlight the importance of incorporating phylogenetic information to improve our understanding of floristic assembly from an evolutionary perspective. The review ends with a brief outlook on future challenges for phylofloristic studies, including generating a highly resolved species-level phylogenetic tree, compiling detailed and refined information regarding the geographic distribution of all plant life, extracting trait information from publications and herbarium specimens, and developing technological and methodological approaches for big data analysis. 展开更多
关键词 Big data BIOGEOGRAPHY ECOLOGY Evolution FLORA Mega-phylogeny
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Studies on diversity of higher fungi in Yunnan, southwestern China:A review 被引量:5
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作者 Bang Feng Zhuliang Yang 《Plant Diversity》 SCIE CAS CSCD 2018年第4期165-171,共7页
Yunnan is exceedingly rich in higher fungi(Ascomycota and Basidiomycota). Given that the number of fungi(including lichens) occurring in a given area is, as Hawksworth suggested, roughly six times that of local vascul... Yunnan is exceedingly rich in higher fungi(Ascomycota and Basidiomycota). Given that the number of fungi(including lichens) occurring in a given area is, as Hawksworth suggested, roughly six times that of local vascular plants, a total of approximately 104,000 fungal species would be expected in Yunnan.However, to date only about 6000 fungal species, including roughly 3000 species of higher fungi, have been reported from the province. Although studies on Yunnan's fungi started in the late nineteenth century, significant progress has been made only in the last forty-five years. Over the first twenty-five years of this period, studies on fungal diversity in this area have largely been about taxonomy based on morphological characters and partially on geographical distribution. Over the past twenty years, the combination of both morphological and molecular phylogenetic approaches has become the preferred method to help understand the diversity and evolution of higher fungi. This review focuses on our current knowledge of how geological, geographical, and ecological factors may have contributed to the diversity patterns of higher fungi in Yunnan. Based on this knowledge, three aspects for future studies are suggested. 展开更多
关键词 ASCOMYCOTA BASIDIOMYCOTA BIOGEOGRAPHY Evolution Fungal diversity YUNNAN
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Seasonal comparison of bacterial communities in rhizosphere of alpine cushion plants in the Himalayan Hengduan Mountains 被引量:4
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作者 Shuai Chang Jianguo Chen +2 位作者 Jianqiang Su Yang Yang Hang Sun 《Plant Diversity》 SCIE CAS CSCD 2018年第5期209-216,共8页
Positive associations between alpine cushion plants and other species have been extensively studied.However,almost all studies have focused on the associations between macrofauna.Studies that have investigated positiv... Positive associations between alpine cushion plants and other species have been extensively studied.However,almost all studies have focused on the associations between macrofauna.Studies that have investigated positive associations between alpine cushion plants and rhizospheric microbes have been limited to the vegetation growing season.Here,we asked whether the positive effects that alpine cushion plants confer on rhizospheric microbe communities vary with seasons.We assessed seasonal variations in the bacterial diversity and composition in rhizosphere of two alpine cushion plants and surrounding bare ground by employing a high throughput sequencing method targeting the V3 region of bacterial 16 S rRNA genes.Soil properties of the rhizosphere and the bare ground were also examined.We found that cushion rhizospheres harbored significantly more C,N,S,ammonia nitrogen,and soil moisture than the bare ground.Soil properties in cushion rhizospheres were not notably different,except for soil pH.Bacterial diversities within the same microhabitats did not vary significantly with seasons.We concluded that alpine cushion plants had positive effects on the rhizospheric bacterial communities,even though the strength of the effect varied in different cushion species.Cushion species and the soil sulfur content were probably the major factors driving the spatial distribution and structure of soil bacterial communities in the alpine communities dominated by cushion plants. 展开更多
关键词 ALPINE Cushion plant Positive effect RHIZOSPHERE BACTERIA Soil nutrient
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Genomic selection methods for crop improvement:Current status and prospects 被引量:16
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作者 Xin Wang Yang Xu +1 位作者 Zhongli Hu Chenwu Xu 《The Crop Journal》 SCIE CAS CSCD 2018年第4期330-340,共11页
With marker and phenotype information from observed populations, genomic selection (GS) can be used to establish associations between markers and phenotypes. It aims to use genome-wide markers to estimate the effect... With marker and phenotype information from observed populations, genomic selection (GS) can be used to establish associations between markers and phenotypes. It aims to use genome-wide markers to estimate the effects of all loci and thereby predict the genetic values of untested populations, so as to achieve more comprehensive and reliable selection and to accelerate genetic progress in crop breeding. GS models usually face the problem that the number of markers is much higher than the number of phenotypic observations. To overcome this issue and improve prediction accuracy, many models and algorithms, including GBLUP, Bayes, and machine learning have been employed for GS. As hot issues in GS research, the estimation of non-additive genetic effects and the combined analysis of multiple traits or multiple environments are also important for improving the accuracy of prediction. In recent years, crop breeding has taken advantage of the development of GS. The principles and characteristics of current popular GS methods and research progress in hese methods for crop improvement are reviewed in this paper. 展开更多
关键词 Genomic selection PREDICTION ACCURACY CROP
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Antimutagenic potential of curcumin on chromosomal aberrations in Allium cepa 被引量:3
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作者 RAGUNATHAN Irulappan PANNEERSELVAM Natarajan 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第7期470-475,共6页
Turmeric has long been used as a spice and food colouring agent in Asia. In the present investigation, the antimutagenic potential of curcumin was evaluated in Allium cepa root meristem cells. So far there is no repor... Turmeric has long been used as a spice and food colouring agent in Asia. In the present investigation, the antimutagenic potential of curcumin was evaluated in Allium cepa root meristem cells. So far there is no report on the biological properties of curcumin in plant test systems. The root tip cells were treated with sodium azide at 200 and 300 μg/ml for 3 h and curcumin was given at 5, 10 and 20 μg/ml for 16 h, prior to sodium azide treatment. The tips were squashed after colchicine treatment and the cells were analyzed for chromosome aberration and mitotic index. Curcumin induces chromosomal aberration in Allium cepa root tip cells in an insignificant manner, when compared with untreated control. Sodium azide alone induces chromosomal aberrations significantly with increasing concentrations. The total number of aberrations was significantly reduced in root tip cells pretreated with curcumin. The study reveals that curcumin has antimutagenic potential against sodium azide induced chromosomal aberrations in Allium cepa root meristem cells. In addition, it showed mild cytotoxicity by reducing the percentage of mitotic index in all curcumin treated groups, but the mechanism of action remains unknown. The antimutagenic potential of curcumin is effective at 5 μg/ml in Allium cepa root meristem cells. 展开更多
关键词 Chromosomal aberrations Sodium azide GENOTOXICITY Allium cepa
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Study on Biological Characters of Asparagus macowanii Baker. 被引量:1
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作者 刘方农 彭世逞 刘联仁 《Agricultural Science & Technology》 CAS 2012年第11期2351-2354,共4页
Asparagus macowanfi Baker, is a climbing herbaceous foliage species in genus Asparagus of Liliaceae, This paper summarized its multiple uses, morphologi- cal characteristics, biological habit, reproduction methods, ma... Asparagus macowanfi Baker, is a climbing herbaceous foliage species in genus Asparagus of Liliaceae, This paper summarized its multiple uses, morphologi- cal characteristics, biological habit, reproduction methods, management after cultiva- tion, prevention and control of pests and disease, as well as harvest and grading, with the objective to provide references for the exploitation and utilization of As- paragus macowanii Baker. 展开更多
关键词 Asparagus macowanii Baker Biological Characters Multiple uses
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Use of Several Plant Materials and Chemicals to inhibit Soil Urease Activity and Increase Nitrogen Recovery Rate of Urea by Plant 被引量:6
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作者 XU WEIHONG, WANG ZHENGYIN, JIA ZHONGYUAN, HUANG YUN, YUAN LUJIANG and WANG JUANMEICollege of Resources and Environmental Science, Southwest Agricultural University, Chongqing 400716 (China) 《Pedosphere》 SCIE CAS CSCD 2002年第3期275-282,共8页
Effects of residues of 9 plants, lemon eucalyptus (Eucalyptus citriodoraHook., P_1), robust eucalyptus (E. robusta Smith, P_2), Nepal camphortree (Cinnamomum glanduliferum(Wall.) Nees, P_3), tea (Camellia sinensis (Li... Effects of residues of 9 plants, lemon eucalyptus (Eucalyptus citriodoraHook., P_1), robust eucalyptus (E. robusta Smith, P_2), Nepal camphortree (Cinnamomum glanduliferum(Wall.) Nees, P_3), tea (Camellia sinensis (Linn.) O. Ktze. f., P_4), oleander (Nerium indicum Mill,P_5), rape (Brassica campestris L., P_g), Chinese tallow tree (Sapium sebiferum L., P_7), tung(Vernicia fordii (Hemsl.), P_8), and croton (Croton tiglium L., P_9), 7 chemicals, boric acid (C_1),borax (C_2), oxalic acid (C_3), sodium oxalite (C_4), sodium dihydrogen phosphate (C_6), sodiumsilicate (C_7) and sodium citrate (C_8), and a natural organic substance, humic acid (C_5), onurease activity of a neutral purple soil and recovery of urea nitrogen by maize were studied throughincubation and pot experiments. Hydroquinone (HQ) was applied as the reference inhibitor. Afterincubation at 37℃ for 24 h, 7 inhibitors with higher ability to inhibit urease activity wereselected and then incubated for 14 days at 25℃. Results of the incubation experiments showed thatsoil urease activity was greatly inhibited by them, and the inhibition effect followed an order ofP_2>P_4>C_3>C_2>P_3>C_1>HQ>P_1. The 7 selected materials reduced the accumulative amounts of Nreleased from urea and the maximum urease activity by 11.7%~28.4% and 26.7%~39.7%, respectively,and postponed the N release peak by 2~4 days in the incubation period of 14 days under constanttemperature, as compared to the control (no inhibitor). In the pot experiment with the 7 materialsat two levels of addition, low (L) and high (H), the C_1 (H), C_3 (H), C_1 (L), P_4 (L) and C_2 (L)treatments could significantly increase the dry weights of the aboveground parts and the totalbiomass of the maize plants and the apparent recovery rate of urea-N was increased by 6.3%~32.4% ascompared to the control (no hibitor). 展开更多
关键词 CHEMICALS plant materials recovery rate of fertilizer nitrogen ureaseactivity
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Diversity of desert rangelands of Tunisia 被引量:1
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作者 Mouldi Gamoun Azaiez Ouled Belgacem Mounir Louhaichi 《Plant Diversity》 SCIE CAS CSCD 2018年第5期217-225,共9页
Plants are important components of any rangeland.However,the importance of desert rangeland plant diversity has often been underestimated.It has been argued that desert rangelands of Tunisia in good ecological conditi... Plants are important components of any rangeland.However,the importance of desert rangeland plant diversity has often been underestimated.It has been argued that desert rangelands of Tunisia in good ecological condition provide more services than those in poor ecological condition.This is because rangelands in good condition support a more diverse mixture of vegetation with many benefits,such as forage for livestock and medicinal plants.Nearly one-quarter of Tunisia,covering about 5.5 million hectares,are rangelands,of which 87% are located in the arid and desert areas(45% and 42%,respectively).Here,we provide a brief review of the floristic richness of desert rangelands of Tunisia.Approximately 135 species are specific to desert rangelands.The predominant families are Asteraceae,Poaceae,Brassicaceae,Chenopodiaceae,and Fabaceae.These represent approximately 50% of Tunisian desert flora. 展开更多
关键词 VEGETATION DRYLAND Species richness
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Identification of Rhodiola species by using RP-HPLC 被引量:2
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作者 王强 阮晓 +2 位作者 金志华 颜启传 屠善军 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第6期477-482,共6页
An approach was established using RP-HPLC (reversed-phase high-performance liquid chromatography) to identify ten species of Rhodiola, R. coccinea A. Bor, R. junggarica C.Y. Yang et N.R. Cui spn., R. heterodonta A. Bo... An approach was established using RP-HPLC (reversed-phase high-performance liquid chromatography) to identify ten species of Rhodiola, R. coccinea A. Bor, R. junggarica C.Y. Yang et N.R. Cui spn., R. heterodonta A. Bor, R. linearifolia A. Bor, R. pamiro alaiucm A. Bor, R. kaschgarica A. Bor, R. litwinowii A. Bor, R. gelida schrenk, R. rosea L. and R. quadrifide Fisch et Mey collected from the Tianshan Mountains areas of China. Chromatograms of alcohol-soluble proteins, generated from these ten Rhodiola spp. were compared. Each chromatogram of alcohol-soluble proteins came from a single seed of one wild species only. The results showed that when using a Waters Delta Pak. C18, 5 μm particle size reversed phase column (150 mm×3.9 mm), a linear gradient of 22%?55% solvent B with a flow rate of 1 ml/min and a run time of 67 min, the chromatography gave optimum separation of Rhodiola alcohol-soluble proteins. Chromatogram of each species was different and could be used to identify those species. Cluster analysis of genetic similarity coefficients of 37% to 60% showed a medium degree of genetic diversity among the species in these eco-areas. Cluster analysis showed that the ten species of Rhodiola can be divided into four clusters and yielded the general and unique biochemical markers of these species. RP-HPLC was shown to be a rapid, repeatable and reliable method for Rhodiola species identification and analysis of genetic diversity. 展开更多
关键词 RHODIOLA Genetic diversity Species identification RP-HPLC
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Leaf choice in black-and-white snub-nosed monkeys Rhinopithecus bieti is related to the physical and chemical properties of leaves 被引量:6
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作者 Zhipang HUANG Sheng HUO +2 位作者 Shuguo YANG Liangwei CUI Wen XIAO 《Current Zoology》 SCIE CAS CSCD 北大核心 2010年第6期643-649,共7页
To understand the effects of the chemical and physical properties of plant leaves on food choice in Rhinopithecus bieti, we collected mature leaves of nine food and five non-food plant species at the southernmost part... To understand the effects of the chemical and physical properties of plant leaves on food choice in Rhinopithecus bieti, we collected mature leaves of nine food and five non-food plant species at the southernmost part of the species's range. Chemical properties such as fat, ash, crude protein (CP), total phenolics (TP), and fiber content including neutral detergent fiber (NDF), acid detergent fiber (ADF), lignin, celluloses and hemicelluloses, and physical toughness were measured. R. bieti tended to choose leaves with lower fiber content, higher ash, a higher ratio of CP/ADF, and lower toughness. No difference was found for fat, crude protein, total phenolics, hemicelluloses and lignin between food and non-food leaves. Even though the ratio of CP/ADF is generally regarded as a good indicator for colobine food choice, the difference in the ratio of CP/ADF between food and non-food leaves was only the result of differences in ADE Since positive correlations were found between ADF and tough- ness from all leaves (both food and non-food species), and toughness of leaves was likely easier for R. bieti to sense than fiber content via mastication, the toughness of leaves may function as a predictor of food choice in this species [Current Zoology 56 (6) 643-49, 2010]. 展开更多
关键词 Rhinopithecus bieti Diet selection Protein-to-fiber ratio TOUGHNESS Mt. Longma YUNNAN
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Essential Oil Composition of Six Pinus L. Taxa (Pinaceae) from Canada and Their Chemotaxonomy 被引量:1
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作者 Omer Kilic Alpaslan Kocak 《Journal of Agricultural Science and Technology(B)》 2014年第1期67-73,共7页
In this study six Pinus L. taxa from Canada (P. strobus L., P. parviflora Siebold & Zucc., P. mugo Turra subsp, mugo, P. resinosa Sol. ex Alton, P. flexilis E. James and P. nigra J. F. Arnold) were studied to deter... In this study six Pinus L. taxa from Canada (P. strobus L., P. parviflora Siebold & Zucc., P. mugo Turra subsp, mugo, P. resinosa Sol. ex Alton, P. flexilis E. James and P. nigra J. F. Arnold) were studied to determine on chemical characters of studied taxa. For this purpose, essential oil from needles of the six Pinus taxa were investigated by HS-SPME/GC-MS. 38, 33, 39, 28, 31 and 46 compounds were respectively identified from each species representing 95.90%, 95.07%, 95.79%, 96.20%, 93.05% and 96.25% of the oil. The results have given some clues on the chemotaxonomy of this genus and are of usable potentials of the plants as renewable resources. Although the essential oil composition of studied taxa showed chemical divergences because of climatical, seasonal, geographical and geological factors, but the major compounds of plant derivatives are generally similar and the major compounds are chemotaxonomical markers for studied taxa. 展开更多
关键词 PINUS PINACEAE essential oil CANADA HS-SPME/GC-MS.
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Establishment of a transplantation tumor model of human osteosarcoma in chick embryo 被引量:2
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作者 Jianping Wang Lihong Wang Lin Cai 《The Chinese-German Journal of Clinical Oncology》 CAS 2009年第9期531-536,共6页
Objective: We established a transplantation tumor model of human osteosarcoma in chick embryo, studied its morphological and biological characteristics, and observed its dynamic process of angiogenesis induction so th... Objective: We established a transplantation tumor model of human osteosarcoma in chick embryo, studied its morphological and biological characteristics, and observed its dynamic process of angiogenesis induction so that a simple and practical model can be provided for studying osteosarcoma. Methods: Human osteosarcoma cells at different concentrations were inoculated in chorioallantoic membrane (CAM) of chick embryos at different embryonic ages to observe the factors affecting the survival of the transplanted osteosarcoma in chick embryo, growth characteristics of the transplantation tumor, and the morphological characteristics and biological characteristics of the transplantation tumor. Results: The transplantation tumor model of human osteosarcoma in chick embryo was successfully established. It was found that the transplantation tumor was easy to grow and it showed strong angiogenesis-inducing effects. Under the light microscope, the transplantation tumor showed a similar tissue structure to human osteosarcoma. Conclusion: It is feasible to establish a transplantation tumor model of human osteosarcoma in chick embryo. The model can be easily duplicated with a simple operation, which provides a useful animal model for studying osteosarcoma. 展开更多
关键词 animal model chick embryo chorioallantoic membrane OSTEOSARCOMA
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Pollination ecology in China from 1977 to 2017 被引量:5
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作者 Zongxin Ren Yanhui Zhao +4 位作者 Huan Liang Zhibin Tao Hui Tang Haiping Zhang Hong Wang 《Plant Diversity》 SCIE CAS CSCD 2018年第4期172-180,共9页
China is one of most biodiverse countries in the world, containing at least 10% of all angiosperm species.Therefore, we should anticipate a diverse, pollinator fauna. China also has a long history of applied ethnobiol... China is one of most biodiverse countries in the world, containing at least 10% of all angiosperm species.Therefore, we should anticipate a diverse, pollinator fauna. China also has a long history of applied ethnobiology, including a sustainable agriculture based on apiculture and plant-pollinator interactions.However, the science of pollination ecology is a far younger sub-discipline in China, compared to in the West. Chinese studies in pollination ecology began in the 1970 s. For this review, we compiled a complete reference database(>600 publications) of pollination studies in China. Using this database, we identified and analyzed gaps and limitations in research on the pollination systems of native and naturalized species. Specifically, we asked the following questions: 1) What do we know about the pollination systems of native, Chinese species? 2) How does Chinese pollination ecology compare with the development of pollination research abroad and which aspects of research should be pursued by Chinese anthecologists in the near future? 3) What research on pollination in China will advance our understanding and contribute to our ongoing analyses of endemism and conservation? Subsequently, we segregated and identified prospective lines of future research that are unique to China and can only be done in China. This requires discussing priorities within a systematic approach. 展开更多
关键词 China BIODIVERSITY CONSERVATION HIMALAYAS POLLINATION POLLINATORS
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Is kinase activity essential for biological functions of BRI1? 被引量:10
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作者 Weihui Xu Juan Huang +2 位作者 Baohua Li Jiayang Li Yonghong Wang 《Cell Research》 SCIE CAS CSCD 2008年第4期472-478,共7页
Brassinosteroids (BRs) are a major group of plant hormones that regulate plant growth and development. BRI1, a protein localized to the plasma membrane, functions as a BR receptor and it has been proposed that its k... Brassinosteroids (BRs) are a major group of plant hormones that regulate plant growth and development. BRI1, a protein localized to the plasma membrane, functions as a BR receptor and it has been proposed that its kinase activity has an essential role in BR-regulated plant growth and development. Here we report the isolation and molecular characterization of a new allele of bril, bril-301, which shows moderate morphological phenotypes and a reduced response to BRs under normal growth conditions. Sequence analysis identified a two-base alteration from GG to AT, resulting in a conversion of 989G to 9891 in the BRI1 kinase domain. An in vitro assay of kinase activity showed that bril-301 has no detectable autophosphorylation activity or phosphorylation activity towards the BRI1 substrates TTL and BAK1. Furthermore, our results suggest that bril-301, even with extremely impaired kinase activity, still retains partial function in regulating plant growth and development, which raises the question of whether BRI1 kinase activity is essential for BR-mediated growth and development in higher plants. 展开更多
关键词 BRASSINOSTEROID bril kinase activity Arabidopsis thaliana
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Antioxidant power of phytochemicals from Psidium guajava leaf 被引量:14
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作者 钱和 NIHORIMBEREVenant 《Journal of Zhejiang University Science》 CSCD 2004年第6期676-683,共8页
Dried ground leaves of Psidium guajava L. (guava) were extracted by water and aqueous ethyl alcohol 50% (1:10) ratio, and the total phenolic content in the extracts was determined spectrophotometrically according to ... Dried ground leaves of Psidium guajava L. (guava) were extracted by water and aqueous ethyl alcohol 50% (1:10) ratio, and the total phenolic content in the extracts was determined spectrophotometrically according to Folin- Ciocalteu’s phenol method and calculated as gallic acid equivalent (GAE). Remarkably high total phenolic content 575.3 ±15.5 and 511.6±6.2 mg of GAE/g of dried weight material (for ethanol guava leaf extracts and water guava leaf extracts, respectively) were obtained. The antioxidant activity of lyophilized extracts was determined at ambient temperature by means of a 2,2-diphenyl-1-picrylhydryzyl (DPPH˙) colorimetry with detection scheme at 515 nm. The activity was evalu- ated by the decrease in absorbance as the result of DPPH˙ color change from purple to yellow. The higher the sample concentration used, the stronger was the free radical-scavenging effect. The results obtained showed that ascorbic acid was a substantially more powerful antioxidant than the extracts from guava leaf. On the other hand, the commercial guava leaf extracts and ethanol guava leaf extracts showed almost the same antioxidant power whereas water guava leaf extracts showed lower antioxidant activity. The parameter EC50 and the time needed to reach the steady state to EC50 concentration ( TEC50 ) affected the antiradical capacity of the sample. The antioxidant efficiency (AE) has been shown to be a more ade- quate parameter for selecting antioxidants than the widely used EC50. This study revealed that guava leaf extracts comprise effective potential source of natural antioxidants. 展开更多
关键词 Antioxidant capacity Radical-scavenging activity DPPH˙ free-radical COLORIMETRY GUAVA POLYPHENOL
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Generation and characterization of expressed sequence tags(ESTs) from coralloid root cDNA library of Cycas debaoensis 被引量:1
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作者 Yunhua Wang Nan Li +1 位作者 Ting Chen Yiqing Gong 《Plant Diversity》 SCIE CAS CSCD 2018年第5期245-252,共8页
A normalized full-length cDNA library was constructed from the coralloid roots of Cycas debaoensis by the DSN (duplex-specific nuclease) normalization method combined with the SMART (Switching Mechanism At 5' end ... A normalized full-length cDNA library was constructed from the coralloid roots of Cycas debaoensis by the DSN (duplex-specific nuclease) normalization method combined with the SMART (Switching Mechanism At 5' end of the RNA Transcript) technique. The titer of the original cDNA library was about 1.5 × 10^6 cfu·mL^-1 and the average insertion size was about 1 kb with a high recombination rate (97%). The 5011 high-quality expressed sequence tags (ESTs) were obtained from 5393 randomly picked cDNA clones. Clustering and assembly of ESTs resulted in 2984 unique sequences, consisting of 618 contigs and 2366 singlets. EST sequence annotation revealed that 2333 and 1901 unigenes were functionally anno- tated in the NCBI non-redundant database and Swiss-Prot protein database, respectively. Functional analysis demonstrated that 1495 (50.1%) unigenes were associated with 4082 Gene Ontology (GO) terms. A total of 847 unigenes were grouped into 22 Cluster of Orthologous Groups (COG) functional categories. Based on the EST dataset, 22 ESTs that encoded putative receptor-like protein kinase (RLK) genes were screened. Furthermore, a total of 94 simple sequence repeats (SSRs) were discovered, of which 20 loci were successfully amplified in C debaoensis. This study is the first EST analysis for the coralloid roots of C debaoensis and provides a valuable genomic resource for novel gene discovery, gene expression and comparative genomics, conservation and management studies as well as applications in C debaoensis and related cycad species. 展开更多
关键词 Cycas debaoensis Coralloid root cDNA library Expressed sequence tags Symbiosis and defense SSRS
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Ethnobotany, Pharmacology and Chemistry of Medicinal Orchids from Veracruz
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作者 Leticia Margarita Cano Asseleih Rebeca Alicia Menchaca Garcia Jose Yader Sageth Ruiz Cruz 《Journal of Agricultural Science and Technology(A)》 2015年第9期745-754,共10页
Orchidaceae is a large family of 1,260 species in Mexico, of which 433 grow in the state of Veracruz, Mexico. Although economically important in horticulture because of the beauty of their flowers, researches have don... Orchidaceae is a large family of 1,260 species in Mexico, of which 433 grow in the state of Veracruz, Mexico. Although economically important in horticulture because of the beauty of their flowers, researches have done little work regarding their medicinal properties. This paper aimed to present the results of ethnobotanical, pharmacological and active compounds research on Veracruz medicinal orchids. The ethnobotanical information was obtained by consulting the Atlas of the Mexican Traditional Medicine Plants, Veracruz Medicinal Flora Database (CITRO-UV project) and through field work in the Nahuatl community of Cuautlajapa, Veracruz. To obtain pharmacological and active compounds information of registered species, a search was carded out through MEDLINE (USA National Library of Medicine Journal Citation database). Twelve medicinal orchids were recorded for Veracruz, i.e., Epidendrum chlorocorymbos Schltr., Habenaria floribunda Lindl., Isochillus latibracteatus A. Rich. & Galeotti, lsochillus major Schltdl. & Cham., Mormodes maculata var. unicolor (Hook.) L. O. Williams, Oestlundia luteorosea (A. Rich. & Galeotti) W. E. Higgins, Oncidium ascendens Lindl., Scaphyglottis fasciculata Hook., Sobralia macrantha Lindl., Spiranthes eriophora (Rob. & Greenm.), Stanhopea oculata (G. Lodd.) Lindl. and Vanilla planifolia Andrews. Only two species have been investigated in terms of their pharmacology and active compounds. Also, information for another five species closely related to already identified ones was obtained. Given the relative poverty of current information on the topic, this paper demonstrates the need to further study the ethnobotanical, pharmacological and chemical aspects of the region's medicinal orchids. 展开更多
关键词 ORCHIDS medicinal orchids traditional medicine Veracruz medicinal orchids.
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