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等位基因的种数与群体基因型种数的关系
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作者 陈世友 《生物学教学》 北大核心 2001年第7期40-40,共1页
关键词 “等位基因” “种数” “群体基因型” 中学 中国 生物教学
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Fungi Diversity of Ginseng Rhizosphere Soil in Northeastern China 被引量:8
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作者 陈曦 孙晓东 +1 位作者 毕思远 吕国忠 《Agricultural Science & Technology》 CAS 2010年第2期132-136,共5页
[Objective] The aim was to know the pathogenic fungi types and distribution law in ginseng rhizosphere soil.[Method] During May to Oct.in 2008 and 2009,more than 200 soil samples were collected from ginseng rhizospher... [Objective] The aim was to know the pathogenic fungi types and distribution law in ginseng rhizosphere soil.[Method] During May to Oct.in 2008 and 2009,more than 200 soil samples were collected from ginseng rhizosphere soil in Ji an City,Fusong County of Jilin Province and Huanren County of Liaoning Province.Soil dilution plate method and soil particle method were adopted to isolate and culture soil fungi,then classification and identification were carried out.[Result] 33 species of 22 fungal genera were id... 展开更多
关键词 MICROORGANISM ECOLOGY SPECIES Quantity
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Population Density and Habitat Utilization of Ibex(Capra ibex)in Tomur National Nature Reserve,Xinjiang,China 被引量:9
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作者 徐峰 马鸣 吴逸群 《Zoological Research》 CAS CSCD 北大核心 2007年第1期53-55,共3页
Surveys was conducted to study the population density and habitat utilization of the ibex (Capra ibex) in Tomur National Nature Reserve during October- December 2005. The results are as follows: ① The mean group s... Surveys was conducted to study the population density and habitat utilization of the ibex (Capra ibex) in Tomur National Nature Reserve during October- December 2005. The results are as follows: ① The mean group size of the ibex in Tomur Nature Reserve is 8.43 and the population density is 269.76/100 km^2; ② The ibex prefer areas with steep slope (between 30° -45°), broken substrates and cliffs nearby ( 〈 100 m). They avoid grasslands and fiat hillsides; ③The probable reason for this habitat selection is serf-protection. 展开更多
关键词 IBEX POPULATION Habitat utilization Tomur National Nature Reserve
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Living characteristics of rare and endangered species Davidia involucrata 被引量:5
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作者 吴钢 韩单恒 +3 位作者 王宏昌 罗跃初 邓红兵 赵景柱 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第1期39-44,J002,共7页
Dovetree (Davidia involucrate), one of the first-class protective plants in China, is a relic species of paleotropical kingdom in Tertiary period, belonging toDavidiaceae with a single genus. In recent years, the incr... Dovetree (Davidia involucrate), one of the first-class protective plants in China, is a relic species of paleotropical kingdom in Tertiary period, belonging toDavidiaceae with a single genus. In recent years, the increase of regional developing projects has led to a sharp decrease of this ancient and rare plant in naturally distributed habitats and natural population. In this paper, the biological and ecological characteristics of Dovetree were described, and the geographically distributed condition of this species in different geologic periods as well as the major reasons for dynamic changes of its population were systematically analyzed in accordance with field researches and references. The investigations conducted in different years by setting up standard sample plots showed that the population number of Dovetree increased yearly in the areas without human interference but decreased yearly in the areas with human interference. With the increase of population density and human activities decreased as the logarithmic curve:Y=?100.7ln(x)+178.09, and it has turned from a dominant population into an endangered population. Based on the former and present studies on Dovetree, some protection strategies were put foreword for protecting this ancient and rare species. Keywords Davidia involucrate - Dovetree - Geographical Distribution - Biological Characteristics - Protection Policy CLC number S718.4 Document code A Article ID 1007-662X(2004)01-0039-06 Foundation Item: This research was coordinated by the National Natural Science Foundation of China (No. 39970591)Biography: Wu Gang (1965-), Male, Professor in Key Laboratory of Systems Ecology, Research Center for Eco Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.Responsible editor: Chai Ruihai 展开更多
关键词 Davidia involucrate Dovetree Geographical Distribution Biological Characteristics Protection Policy
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RFLP Detection of Genetic Variation of Maize Inbred Lines 被引量:11
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作者 李新海 傅骏骅 +2 位作者 张世煌 袁力行 李明顺 《Acta Botanica Sinica》 CSCD 2000年第11期1156-1161,共6页
Genetic similarities of 13 inbred lines of maize (Zea mays L.) were analyzed by restriction fragment length polymorphisms (RFLPs). The objectives of the study were to detect genetic similarities among 13 inbreds and t... Genetic similarities of 13 inbred lines of maize (Zea mays L.) were analyzed by restriction fragment length polymorphisms (RFLPs). The objectives of the study were to detect genetic similarities among 13 inbreds and to assign them to heterotic groups. By means of 24 probe_enzyme combinations (PECs) selected for locus specificity, clear patterns and reproducibility, 85 alleles were found with an average of 3.3 alleles per locus. The allelic frequency data were used to estimate genetic similarities among lines, and as a result the diversity index of 0.499 was obtained. Genetic similarities between the pairs of 13 lines ranged from 0.523 up to 0.802 with an average of 0.649. The UPGMA clustering algorithm analysis classified the 13 lines into five groups, which generally corresponded to known maize heterotic groups based on pedigree information. The authors concluded that RFLP_based markers could be used for investigating genetic relationships between maize inbred lines and assigning them to heterotic groups, but it seemed that a large number of PECs were needed to obtain reliable estimates of genetic similarity. 展开更多
关键词 Zea mays restriction fragment length polymorphisms (RFLPs) genetic similarity (GS) heterotic gro`
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Meiotic Behavior of 1BL/1RS Translocation Chromosome and Alien Chromosome in Two Tri-genera Hybrids 被引量:3
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作者 李义文 李振声 贾旭 《Acta Botanica Sinica》 CSCD 2002年第7期821-826,共6页
The behavior of wheat-rye translocation chromosome and alien chromosome including Thinopyrum and Haynaldia chromosome at meiosis was investigated in two hybrids by fluorescence in situ hybridization (FISH). Misdivisio... The behavior of wheat-rye translocation chromosome and alien chromosome including Thinopyrum and Haynaldia chromosome at meiosis was investigated in two hybrids by fluorescence in situ hybridization (FISH). Misdivision of translocation chromosome at anaphase I and rye chromatin micronucleus at tetrad stage were observed, A plant with one normal 1BL/1RS translocation chromosome and one 1BL/1RS translocation chromosome deleted about 1/3 of rye chromosome arm in length was identified. One plant with wheat-Thinopyrum non-Robertson translocation chromosome was also detected in the F-2 population of Yi4212 x Yi4095. That could be the results of unequal misdivision of wheat-rye 1BL/1RS translocation chromosome and Thinopyrum chromosome during meiosis. No interaction between translocation chromosome and alien chromosome at meiosis was supported by the data of the distribution frequencies of translocation chromosome and Thinopyrum or Haynaldia chromosome in the progeny of two hybrids. The results may be useful to cultivate new germplasms with different length of rye 1R short arm and wheat-alien non-Robertson translocation tines under wheat background. 展开更多
关键词 MEIOSIS chromatin univalent 1BL/1RS translocation chromosome fluorescence in situ hybridization
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Characteristics of natural Japanese yew population in Muling Nature Reserve of Heilongjiang Province,China 被引量:1
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作者 刘彤 周志强 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第2期132-134,共3页
The scalar of Japanese yew (Taxus cuspidata) population and the relationship between individual distribution and site factors were analyzed according to investigating data in 74 sample belts with a total sampled are... The scalar of Japanese yew (Taxus cuspidata) population and the relationship between individual distribution and site factors were analyzed according to investigating data in 74 sample belts with a total sampled area of 436.872 hm2 in Muling Nature Reserve. The result showed that the distribution rules of Japanese yew population were correlated to elevation, slope position, slope aspect and slope gradient. The optimal distribution range in elevation for the natural Japanese yew population is at the attitudes of 700-800 m. The amounts of Japanese yew individuals on shady slope were more than those on sunny slope. On top slope and mid-slope, the individual amounts of Japanese yew are more than those on toe slope. Most of Japanese yew individuals occurred on slope gradient of less than 15. The scalar of the population was decreased with the slope gradient increasing. 展开更多
关键词 Japanese yew Taxus cuspidate Muling Nature Reserve POPULATION
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Difference between Responses of Potato Plant Height to Corrected FAO-56-recommended Crop Coefficient and Measured Crop Coefficient 被引量:4
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作者 陈秋帆 代兴梅 +2 位作者 陈劲松 颜雄 彭尔瑞 《Agricultural Science & Technology》 CAS 2016年第3期551-554,共4页
This study was conducted to establish a simple convenient method for calculating crop coefficient, and provide a certain basis for the research of the empirical formula for calculating crop coefficient with plant heig... This study was conducted to establish a simple convenient method for calculating crop coefficient, and provide a certain basis for the research of the empirical formula for calculating crop coefficient with plant height which could be measured conveniently with regional differences, especially for the establishment of accurate irrigation schedule of potato in Yunnan. By the field experiment on potato under the condition of drip irrigation, it was found that the models of plant height with corrected FAO-56-recommended K and measured K were a quartic polynomial and a cubic polynomial, respectively, and the polynomial of potato plant height with measured crop coefficient was simpler with higher degree of fitting; and the differences between the period with the highest change rate of potato plant height and the periods with the greatest FAO-56-recommended K and measured K exhibited a differences of 3 d. In conclusion: In the future study of simple or empirical formula calculation of crop coefficient, plant height should be considered as a main dependent variable in that the calculation result would be closer to the measured crop coefficient with the problem of regional difference existing in the FAO method solved and the formula might be simpler; and the irrigation time of potato should be 3 d earlier than the irrigation time determined according to the corrected FAO-56-recommended crop coefficient, especially in the key water requirement stages of potato. 展开更多
关键词 POTATO Plant height Crop coefficient Field planting
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Establishment and Share of Tea Germplasm Database of Yunnan Province 被引量:1
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作者 蒋会兵 矣兵 王平盛 《Agricultural Science & Technology》 CAS 2011年第12期1966-1971,共6页
[Objective] The paper was to establish tea germplasm database of Yunnan Province,and promote sharing of the tea germplasm resources.[Method] Eight hundred and thirty copies of tea germplasm resources of Yunnan Provinc... [Objective] The paper was to establish tea germplasm database of Yunnan Province,and promote sharing of the tea germplasm resources.[Method] Eight hundred and thirty copies of tea germplasm resources of Yunnan Province were first systematically documented by using Access database software,the generic description of 631 tea resources and characteristic description of 300 tea resources were submitted for e-platform,then linked with the national e-platform for natural scientific and technological resources,and the tea germplasm database of Yunnan Province was established.[Result] Based on the conservation and utilization status of tea germplam resources,the sharing and utilization framework of tea germplam resources was presented.Many problems and suggestion about tea germplasm resources in the process of conservation,documentation concordance and sharing were pointed out.For example,conservation areas were separated and system was not completed;the main traits assessment and identification researching work had not completely accomplished and sharing was inefficient.[Conclusion] The paper laid foundation for standardized,digitized and information-based management of tea germplasm resources. 展开更多
关键词 TEA Germplasm resources DATABASE SHARE
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Description of a New Subspecies of the Genus Saurogobio Bleeker (1870) 被引量:3
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作者 戴应贵 杨君兴 《Zoological Research》 CAS CSCD 北大核心 2002年第4期306-310,共5页
The genus Saurogobio Bleeker (1870) is a group of small sized cyprinids. Saurogobio dabryi Bleeker (1871) is widely distributed in East Asia.On the basis of careful inspection of morphological and meristic ch... The genus Saurogobio Bleeker (1870) is a group of small sized cyprinids. Saurogobio dabryi Bleeker (1871) is widely distributed in East Asia.On the basis of careful inspection of morphological and meristic characters of specimen collected from Chenghai Lake in Yunnan and the opening river systems including Pearl River,Minjiang River,Yangtze River,Liaohe River and Songhuajiang River,the Chenghai Lake population of Saurogobio dabryi is considered to represent a new subspecies, Saurogobio dabryi chenghaiensis . Saurogobio dabryi chenghaiensis is distinguished by the combination of following characters.Rostral cap developed,covering over upper lip,and lips with developed papillae.Body and caudal peduncle very slender,body depth 12 7%-15 0% of standard length(SL),caudal peduncle depth 5 5%-6 1% of SL and 31 8%-39 1% of caudal peduncle length.A longitudinal dark stripe present along the axis on each side of body and 6-11 stick shaped black spots (its widths being 25%-50% of its lengths respectively) occur along the stripe.Distance from pelvic fin origin to anus is more than 50% of pelvic fin length.The length of the shortest caudal fin ray is less than 50% that of the longest one.The new subspecies occurs only in Chenghai Lake,Yunnan,China. 展开更多
关键词 Saurogobio New subspecies Coefficient of difference KEY
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Information Description of Vegetable Planting Metadata Model 被引量:1
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作者 陈宏 赵健 +2 位作者 池美香 邱荣洲 翁启勇 《Agricultural Science & Technology》 CAS 2012年第1期238-241,共4页
[Objective] To study the information description of vegetable planting metadata model. [Method] On the basis of analyzing the data involved in every as- pect of vegetable planting, this paper put forward description s... [Objective] To study the information description of vegetable planting metadata model. [Method] On the basis of analyzing the data involved in every as- pect of vegetable planting, this paper put forward description schemes of vegetable planting metadata and constructed vegetable planting metadata model by the means of XML/XML schema. [Result] Metadata model of vegetable planting was established, and information description of vegetable planting metadata model was realized by the using of XML Schema. The whole metadata model consists of 7 first-class classifica- tions, including more than 800 information description points which could completely record vegetable planting-related information. [Conclusion] Standards for data collec- tion, management and sharing were provided for the agriculture applications in indus- tries like GAP management of vegetable planting, facility vegetable, food quality traceability, etc. 展开更多
关键词 Vegetable planting XML/XML Schema METADATA
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Comparative Advantage of Maize Production in Jilin Province 被引量:2
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作者 张大瑜 吴景贵 +4 位作者 陈日曌 祝延立 吕铁彪 赵仁贵 刘武仁 《Agricultural Science & Technology》 CAS 2010年第6期53-56,共4页
The comparative advantage of maize production in Jilin Province was analyzed based on the sow area index,unit yield index,benefit index and comprehensive comparative advantage index in this study.The results showed th... The comparative advantage of maize production in Jilin Province was analyzed based on the sow area index,unit yield index,benefit index and comprehensive comparative advantage index in this study.The results showed that compared with other provinces in China,there was obvious comparative advantage in sow area index and unit yield index of maize in Jilin,the average of which stood for the first and the fourth in China from 2002 to 2006;there was no comparative advantage of benefit index compared with the average value of the whole countries,the average of which stood for the 14th in China from 2002 to 2006;the comprehensive comparative advantage in Jilin provincial maize production showed significant comparative advantage,the average of which stood for the fourth in China from 2002 to 2006.On the basis of the above,the suggestions to develop maize production in Jilin province had been put forward. 展开更多
关键词 Sow area index Unit yield index Benefit index Comprehensive comparative advantage index MAIZE Jilin Province
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Analysis on Input-Output in Rice Cultivation Based on Cobb-Douglas Production Function 被引量:2
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作者 高雷 《Agricultural Science & Technology》 CAS 2012年第4期716-718,共3页
[Objective] To analyze the input and output in rice cultivation based on CD function. [Method] Based on the input factors, Cobb-Douglas production (CD) function was used to do the quantitative analysis on the input-... [Objective] To analyze the input and output in rice cultivation based on CD function. [Method] Based on the input factors, Cobb-Douglas production (CD) function was used to do the quantitative analysis on the input-output in rice production with rice growers as the objective. [Result] Considering the substitution effect of labor in- put and capital input, under the same technical conditions, the effect of increasing labor input on the rice production in per 667 m2 was negative, based on which 2 pieces of policy suggestions were put forward to promote the transfer of surplus la- bor force of rice growers and ensure the capital supply for rice production. [Conclusion] This study laid the foundation for the realization of reasonable allocation of rice production resources. 展开更多
关键词 Cobb-Douglas production function Rice cultivation INPUT OUTPUT
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Combination of Homoeologous Pairing Gene phKL and Ph2-deficiency in Common Wheat and Its Meiotic Behaviors in Hybrids with Alien Species 被引量:1
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作者 刘登才 郑有良 +3 位作者 颜泽洪 周永红 魏育明 兰秀锦 《Acta Botanica Sinica》 CSCD 2003年第9期1121-1128,共8页
The combined lines having both phKL and Ph2-deficiency were obtained in the genetic background of common wheat (Triticum aestivum L.) landrace. These lines had normal fertility. In the wheat combined lines X Aegilops ... The combined lines having both phKL and Ph2-deficiency were obtained in the genetic background of common wheat (Triticum aestivum L.) landrace. These lines had normal fertility. In the wheat combined lines X Aegilops variabilis Eig. (or rye), a significant increase in the chiasmata of homoeologous pairing was shown by the phKL+Ph2(-) plants with respect to their phKL+Ph2 sibs, which indicates that Ph2-deficiency and phKL showed an additive effect on promoting pairing. The effects were shown in the increment of rod bivalents, ring bivalents and trivalents and reduction of univalents, of which, reduction of univalents was mainly due to the increment of rod bivalents. The combined lines are probably more desirable materials for alien gene transferring than phKL or Ph2(-) lines alone. In comparison with that of ph1b X Ae. variabilis (or rye), phKL+Ph2(-) X Ae. variabilis (or rye) show higher (or similar) numbers of rod bivalents, while the total chromosome pairing level significantly reduced that ascribed to the decrement in ring bivalents and multivalents. These results probably indicate the different genetic mechanisms for Ph1 and Ph2 or phKL on controlling homoeologous pairing. 展开更多
关键词 Triticum aestivum homoeologous pairing Ph gene metaphase- I pairing interspecific hybrid
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读《韩非子新校注》札记 被引量:1
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作者 车淑娅 《古籍整理研究学刊》 2005年第3期67-70,共4页
《韩非子新校注》旨在勘正《韩非子》中的衍、脱、讹、倒,疏证前人校说,训释疑难字词,但在诸如“保”、“大夫种”、“以十数”、“赂”等处有误校或误注,本文就此提出商榷。
关键词 《韩非子新校注》 “保” “大夫种” “以十数”
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Experimental verification of mathematical model for multiphase flow in air-agitated seed precipitation tank 被引量:3
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作者 陈乔平 闫红杰 +1 位作者 葛世恒 周孑民 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第7期1680-1684,共5页
In order to check the validity of the mathematical model for analyzing the flow field in the air-agitated seed precipitation tank,a scaled down experimental apparatus was designed and the colored tracer and KCl tracer... In order to check the validity of the mathematical model for analyzing the flow field in the air-agitated seed precipitation tank,a scaled down experimental apparatus was designed and the colored tracer and KCl tracer were added in the apparatus to follow the real flow line.Virtue tracers were considered in the mathematical model and the algorithm of tracers was built.The comparison of the results between the experiment and numerical calculation shows that the time of the tracer flows out of stirring tube are 40 s in the experiment and 42 s in numerical calculated result.The transient diffusion process and the solution residence time of the numerical calculation are in good agreement with the experimental results,which indicates that the mathematical model is reliable and can be used to predict the flow field of the air-agitated seed precipitation tank. 展开更多
关键词 model experiment numerical simulation multiphase flow seed precipitation
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Analysis and Evaluation Indicator Selection of Chilling Tolerance of Different Cotton Genotypes 被引量:2
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作者 武辉 侯丽丽 +4 位作者 周艳飞 范志超 石俊毅 阿丽艳.肉孜 张巨松 《Agricultural Science & Technology》 CAS 2012年第11期2338-2346,共9页
[Objectivc] This study aimed to investigate the chilling tolerance of seedlings of different cotton genotypes and screen appropriate indicators for assess- ing chilling tolerance, to establish reliable mathematical ev... [Objectivc] This study aimed to investigate the chilling tolerance of seedlings of different cotton genotypes and screen appropriate indicators for assess- ing chilling tolerance, to establish reliable mathematical evaluation model for chilling tolerance of cotton, thus providing theoretical basis for breeding and promoting new chilling-tolerant cotton germplasms and large-scale evaluation of chilling tolerance of cotton varieties. [Method] Fifteen cotton varieties (lines) were used as experimental materials. The photosynthetic gas exchange parameters, chlorophyll fluorescence ki- netic parameters, chlorophyll content, relative soluble sugar content, malonaldehyde content, relative proiine content, relative conductivity and other 12 physiological indi- cators of seedling leaves under low temperature treatment (5 ℃, 12 h) and recovery treatment (25 ℃. 24 h) were determined; based on the chilling tolerance coefficient (CTC) of various individual indicators, the comprehensive evaluation of chilling toler- ance was conducled by using principal component analysis, hierarchical cluster anal- ysis and stepwise regression analysis. [Result] The results showed that the 12 indi- vidual physiological indicators could be classified into 7 independent comprehensive components by principal component analysis; 15 cotton varieties (lines) were clus- tered into three categories by using membership function method and hierarchical cluster analysis; the mathematical model for evaluating chilling tolerance of cotton seedlings was established: D =0.275 -0.244Fo1 +0.206Fv/Fm1+0.326g,%-0.056SS + 0.225MDA+O.O38REC (FF=0.995), and the evaluation accuracy of the equation was higher than 94.25%,0. Six identification indicators closely related to chilling tolerance were screened, including Fo,, Fv/Fm1, Seedling leaves of cotton varieties (lines) gs2, SS, MDA, and REC. [Conclusion] with high chilling tolerance are less dam- aged under low temperature stress, and are able to maintain relatively high photo- synthetic electron transport capacity and high stomatal conductance after recovery treatment, which is contributed to gas exchange and recovery of photosynthetic ca- pacity. Determination of the six indicators under the same stress condition can be adopted for rapid identification and prediction of the chilling tolerance of other cotton varieties, which provides basis for the breeding, promotion, identification and screen- ing of chilling tolerant germplasms. 展开更多
关键词 COTTON Chilling tolerance Principal components analysis Comprehensiveevaluation Stepwise regression analysis
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Status of the Xinjiang Ground Jay:population,breeding ecology and conservation 被引量:1
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作者 马鸣 《Chinese Birds》 2011年第1期59-62,共4页
The Xinjiang Ground Jay (Podoces biddulphi) is a bird species endemic to China. It has a restricted range, living only in the Taklimakan Desert, southern part of Xinjiang. So far, little information has been known of ... The Xinjiang Ground Jay (Podoces biddulphi) is a bird species endemic to China. It has a restricted range, living only in the Taklimakan Desert, southern part of Xinjiang. So far, little information has been known of the status and ecology of the bird in the world. Since 1988, I have been taking field investigations on the distribution, population size and breeding ecology of the Xinjiang Ground Jay in the desert.In this thesis, the desertification in relation to the eastward expansion of the ground jays was discussed. 展开更多
关键词 Xinjiang Ground Jay breeding ecology population size CONSERVATION Taklimakan Desert
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Status and behavior of the Black-necked Crane (Grus nigricollis) in the Altun Mountain Reserve,Xinjiang
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作者 张同 马鸣 +2 位作者 丁鹏 徐峰 Paul J.BUZZARD 《Chinese Birds》 2012年第3期199-205,共7页
The Black-necked Crane (Grus nigricollis) is an endemic species of the Qinghai-Tibetan Plateau,with its population in Xinjiang largely found in the Kunlun and Altun mountain regions.A survey of the distribution,popula... The Black-necked Crane (Grus nigricollis) is an endemic species of the Qinghai-Tibetan Plateau,with its population in Xinjiang largely found in the Kunlun and Altun mountain regions.A survey of the distribution,population dynamics,flock size and behavior was conducted in Altun Mountain National Natural Reserve from September to November 2011.We investigated the size and distribution of its population in this area with a sample spot survey and by direct counting.We found Black-necked Cranes on the wetlands of Wuzunxiaoer,Yusup Aleksei,Yaziquan,Qimantag,Tula Ranch and elsewhere,where we recorded 126 individual birds of the species in Yixiekepati (37° 15′-37°23′N,90°11′-90°20′E,elevation 3903 m),the largest population we have observed in this area.In the reserve,the population consists of about 180-200 birds.Combined with previous records,we conclude that more than 260 Black-necked Cranes live in Xinjiang.Cranes gathered conspicuously in the middle of October where the highest number of birds appeared on 29 October.All of the cranes had migrated out of this area by 6 November.Time budgets and diurnal behavior rhythms of Blacknecked Cranes were observed in the Yixiekepati wetland at daylight (from 06:00 to 18:00).Foraging was the most prevalent type of behavior during the autumn period,accounting for 58.9% of the diurnal time budget,followed by preening (13.2%),vigilance (9.5%),walking (8.2%),flying (3.5%),resting (3.4%),chirping (2.7%) and other types of behavior (0.6%). 展开更多
关键词 Black-necked Crane Grus nigricollis distribution population size behavior rhythm XINJIANG
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Selection of Example Varieties Used in the DUS Test Guideline of Tagetes L. 被引量:1
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作者 刘艳芳 张建华 +6 位作者 王烨 陈海荣 徐云 杨晓洪 张惠 管俊娇 王江民 《Agricultural Science & Technology》 CAS 2012年第10期2110-2111,2116,共3页
[Objective] Taking the characteristic of flower diameter of Tagetes L.as an example,this study aimed to select example varieties used in the DUS Test Guideline of Tagetes L.[Method] Two continuous years of measurement... [Objective] Taking the characteristic of flower diameter of Tagetes L.as an example,this study aimed to select example varieties used in the DUS Test Guideline of Tagetes L.[Method] Two continuous years of measurements of flower diameter of 25 varieties were collected and then analyzed by using the box plot to illustrate the uniformity and stability of flower diameter of each variety.[Result] According to the information of variability,distribution symmetry of measurements and outliers of flower diameter of varieties provided by box plots,variety 16,2 and 4 were selected as the example varieties for the three expression states with respective flower diameter of 3.0-4.4,6.0-7.4 and 9.0-10.4 cm.[Conclusion] The box plot is an efficient method for the general analysis of varieties,which provides information covering the actual and possible expression range,median and outliers of measurements of flower diameter of each variety.It also provides references for selecting example varieties for other quantitative characteristics and evaluating the quality of varieties. 展开更多
关键词 DUS Test Guideline of Tagetes L. Quantitative characteristic Example variety The box plot
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