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Loss of preferred habitat and pollen limitation threatens reproduction in a rare mountain Paeonia delavayi

Journal of Mountain Science 2016年第12期13卷 2147-2154页

作者： LI Wei PAN Wen-wen TAN Rui WANG Juan yunnan Academy of Biodiversity Southwest Forestry University Departments of Biology Lishui Vocational & Technical College Key Laboratory of the State Forestry Administration for Conservation of yunnan Rare Endangered & Endemic Plant /Key Laboratory of Yunnan Provincial for Forest Plant Cultivation and UtilizationYunnan Academy of Forestry

Paeonia delavayi is a wild tree peony species endemic to high-altitude regions in southwestern *** agricultural land expansion,however,not only causes its dwindling population size,but also poses a severe threat to its long-term *** our knowledge of the reproductive biology of *** is very limited,and some management misconceptions have further exacerbated the already worrisome situation,the aim of the present study is to provide some scientific evidence regarding habitat preference and breeding system of ***,and to help correct some management ***,morphological traits of *** populations growing in two different habitats(i.e.,the open area versus forest understory),including basal stem diameter,plant height and flower numbers per plant,were measured and compared with each other.A range of floral manipulation experiments was further conducted to study the extent of self-compatibility and pollen *** results showed that *** preferred the open habitat over forest understory as it generally grew bigger with thickerstems,and produced a higher number of flowers in the former ***,the open habitat should receive immediate priority for conservation action instead of being converted to agricultural land;also,*** is pollen limited,as evidenced by the fact that experimental flowers receiving supplemental non-self pollen generally displayed elevated seed production than flowers subjected to other treatments(e.g.,non-supplemental self pollen,non-supplemental non-self pollen and supplemental self pollen),which is consistent with reported observations that alpine plants are more likely to be pollen-limited than lowland *** suggest that human intervention might be necessary to guarantee the long-term persistence of *** as harsh alpine environment,intense competition for pollinators and different anthropogenic perturbations co-limit its reproductive success.

关键词：栖息地花粉威胁繁殖生物学亏损生境选择农业用地操作实验

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旅游动机对历史文化名城游客满意度与忠诚度的影响——基于大理古城的实证研究

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城市规划:英文版 2023年第3期32卷 6-14页

作者：李璋段晓迪曹磊 Tianjin University Architectural and Civil Engineering Institute West Yunnan University of Applied Sciences Dali vocational and technical college of agriculture and Forestry Department of Landscape Architecture School of ArchitectureTianjin University

Based on the perspective of heritage tourism,this paper selected Dali Ancient City,one of the first group of national historic and cultural cities,located in yunnan Province,China,as case study to analyze the motivation,satisfaction,and loyalty of tourists to national historic and cultural cities with concentrations of ethnic *** the questionnaire survey on the experience of tourists during their stay in Dali Ancient City,the study identified two motivations related to their visit:cultural motivation and multi-factor motivation,such as delicious food,enjoying *** identifying and understanding the type,motivation,behavior,perception,and experience of tourists in national historic and cultural cities,it was hoped to provide reference for destination management and formulation of corresponding *** addition,this study also discussed how tourist motivation analysis contributed to higher satisfaction and loyalty of tourists to a destination.

关键词： national historic and cultural city tourist satisfaction motivation dimension tourist motivation loyalty

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Numerical investigation for effects of natural light and ventilation on 3D tomato body heat distribution in a Venlo greenhouse

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Information Processing in agriculture 2023年第4期10卷 535-546页

作者： Guanghui Yu Shanhong Zhang Shuai Li Minshu Zhang Hüseyin Benli Yang Wang National Innovation Center for Digital Fishery China Agricultural UniversityBeijing 100083China Laboratory of Smart Farming Technologies for Aquatic Animal and Livestock Ministry of Agriculture and Rural AffairsChina Agricultural University100083BeijingChina Engineering and Technology Research Center for Internet of Things in agriculture China Agricultural University100083BeijingChina college of Information and Electrical Engineering China Agricultural UniversityBeijing 100083China Department of technical and vocational Education Firat UniversityTR-23119 ElazigTurkey for Huseyin Benli

Maintaining suitable temperature level around tomato in the greenhouse is essential for the high-quality ***,in summer,the temperature level around the tomato is usually unclear except using a high-precision temperature *** solve this problem,thermal performance of 3D(three-dimensional)tomato model built based on SolidWorks was investigated by the computational fluid dynamics(CFD)*** assess the effect of temperature distribution around the tomato,a simplified 3D tomato numerical model was firstly validated by a set of field measurement *** light intensity and indoor ventilation were regarded as the mainly environment factors in the Venlo greenhouse,thermal stratification around tomatoes at different time of day was further *** numerical results illustrated the different temperature distribution around tomato body under different radiation *** was found that ventilation could obviously adjust the temperature gradient around the tomato,and alleviate high temperature effect particularly in *** ventilation could create a suitable thermal environment for the tomato *** study clearly demonstrated 3D temperature distribution around tomatoes,which is beneficial to provide the reference for accurate detection of 3D tomato temperature and appropriate thermal environment design.

关键词： CFD 3D Tomato body Heat distribution Greenhouse environment Growth condition

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基于阐释资源和实际管理的地质公园阐释系统评价体系及评价模型研究

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艺术管理（中英文） 2022年第2期 44-58页

作者：李璋段晓迪 Tianji University Nankai DistrictTianjin 300072 West yunnan University of Applied Sciences DaliYunnan671000 Dali vocational and technical college of agriculture and Forestry DaliYunnan671000

在综合分析相关评价模型的基础上,本论文探讨了地质公园阐释系统的评价体系和评价模型。主要步骤如下:(1)构建指标体系。综合运用理论方法、频率法和专家咨询法,本论文构建了地质公园阐释系统评价指标体系。评价指标体系包括3个一级指标... 详细信息

在综合分析相关评价模型的基础上,本论文探讨了地质公园阐释系统的评价体系和评价模型。主要步骤如下:(1)构建指标体系。综合运用理论方法、频率法和专家咨询法,本论文构建了地质公园阐释系统评价指标体系。评价指标体系包括3个一级指标、8个二级指标和30个三级指标。(2)确定指标权重和评分标准。本论文采用层次分析法确定评价指标体系中各指标的权重,明确了各指标的测量方法和评分标准。(3)建立评价模型和评价等级。本论文构建了阐释系统开发评价模型,并根据评价结果划分了四个评价等级。(4)实证研究。利用评价指标体系和评价模型,本论文对苍山世界地质公园阐释系统的各项指标进行了测量和调查,然后研究计算每个指标的得分和整个阐释系统的最终得分。评价结果表明,各层次指标得分差异显著。阐释系统总分为7.8854分,表明苍山世界地质公园阐释系统的评价水平较高。针对得分较低的指标,本论文提出了相应的改进对策。

关键词：地质公园阐释系统指标体系指标评价分配标准评价模型评价等级

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Design of flower transplanting mechanisms based on double planet carrier non-circular gear train with complete rotation kinematic pair

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International Journal of Agricultural and Biological Engineering 2022年第3期15卷 9-15页

作者： Xiong Zhao Xingxiao Ma Hongwei Liao Yongsen Xiong Yadan Xu Jianneng Chen Faculty of Mechanical Engineering and Automation Zhejiang Sci-Tech UniversityHangzhou 310018China Key Laboratory of Crop Harvesting Equipment Technology of Zhejiang Province Jinhua 321017ZhejiangChina Hangzhou vocational&technical college Hangzhou 310018China

In view of the problems of the existing mechanisms based on 2R open-chain planetary gear train for seedling transplanting,such as the bad tracking flexibility,low positioning accuracy,and high structure design difficulties of the mechanisms based on 3R open-chain planetary gear train for seedling *** this paper,a transplanting mechanism based on the solution domain synthesis of a 3R open-chain-based complete rotation kinematic pair,a gear train with a single cycle integral rotating pair,is *** Burmester curve equation is derived from the given transplanting trajectory and four exact poses corresponding to each other on the rotation ***,the open-chain road model of the 3R complete rotation kinematic pair is obtained under the constraint governed by the judgment condition of the hinge integral rotating ***,combined with our developed in-house optimization software,the solution to the optimal parameters for the transplanting mechanism can be optimized according to the target ***,the feasibility of the design method is verified by transplanting testing,where kale seedlings with ages of about 20 d and heights of about 80-120 mm are *** experimental results show that the actual motion trajectory of the prototype is basically identical to the theoretical trajectory,validating the feasibility of transplanting mechanism design,parts processing,and test-bed *** the statistical analysis,the average success rate of transplanting is 90.625%,and the reliability of designed mechanism is *** study provides a promising solution for the seedling transplanting of two-planet scaffold pots.

关键词： 3R open-chain planetary gear train complete rotation kinematic pair precise manipulation plug seedling

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Identification of Molecular Markers for a Aphid Resistance Gene in Sorghum and Selective Efficiency Using These Markers

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Journal of Integrative agriculture 2012年第7期11卷 1086-1092页

作者： CHANG Jin-hua CUI Jiang-hui XUE Wei ZHANG Qing-wen college of agriculture and Biotechnology China Agricultural University Beijing 100096 P.R.China college of agriculture Agricultural University ofHebei Baoding 071001 P.R.China Student Employment Guidance Center Baoding Vocational and Technical College Baoding 071001 P.R.China

In this study, an F2 segregated population obtained by hybridization between the aphid-sensitive sorghum strain Qiansan and aphid-resistant cultivar Henong 16 was used to establish an aphid-resistant pool and an aphid-sensitive pool. 192 pairs of AFLP （amplified fragment length polymorphism） marker primers were screened in these pools using BSA （bulked segregant analysis）. Three pairs of EcoR I-CTG/Mse I-CCT, EcoR I-CTG/Mse I-CAT, and EcoR I-AGT/Mse I-CCC showed linkage with aphis resistance. EcoR I-CTG/Mse I-CCT-475, EcoR I-CTG/Mse I-CAT-390, and EcoR I-AGT/Mse I-CCC- 350 （E42/M52-350） were mapped within 6, 10, and 13 cM distances with the aphid-resistant gene by using Mapmaker 3.0 software. The bands amplified by EcoR I-CTG/Mse I-CCT-475 and EcoR I-CTG/Mse I-CAT-390 were extracted, cloned, and sequenced. Specific primers of SCAR （sequence characterized amplified regions） were then designed from these bands. A specific band of 300 bp was amplified by a pair of SCAR primers designed based on the sequence obtained from the EcoR I-CTG/Mse I-CAT-390 marker. The SCAR marker was named SCAS0. The marker was used to detect the F2, BC1, and F2：3 populations. The selective efficiency was 86.8, 91.1, and 86.3% in the BC1, F2, and F2：3 populations, respectively. The average selective efficiency was 88.2%.

关键词： sorghum bicolor aphid resistance gene molecular marker SCAR molecular assistant selection

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Study on PCR rapid molecular detection technique of Meloidogyne vitis

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Journal of Integrative agriculture 2022年第11期21卷 3408-3416页

作者： YANG Yan-mei LIU Pei LI Hong-mei PENG Huan DU Xia DONG Ye HU Xian-qi college of Plant Protection Yunnan Agricultural UniversityKunming 650201.P.R.China State Key Laboratory for Conservation and Utilization of Bio-Resources in yunnan Yunnan Agricultural UniversityKunming 650201P.R.China Institute of Agricultural Environment&Resources Yunnan Academy of Agricultural SciencesKunming 650205P.R.China International college Yunnan Agricultural UniversityKunming 650201P.R.China State Key Laboratory for Biology of Plant Disease and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193P.R.China

Meloidogyne vitis is a new root-knot nematode parasitic on grape root in yunnan Province,*** order to establish a rapid,reliable and specific molecular detection method for ***,the species-specific primers were designed with rDNA-ITS(ribosomal DNA internal transcribed spacer)gene fragment as the *** reaction system was optimized and the reliability,specificity and sensitivity of primer were testified,therefore,a rapid PCR detection method for *** was *** result showed that the optimal annealing temperature of the primers was 53℃,which was suitable for the detection of different life stages of *** test showed that the specific fragment size of 174 bp was obtained from ***,but other five non-target nematodes did not have any amplification bands,thus effectively distinguish *** and the other five species,and could specifically detect the *** from mixed *** test showed that this PCR technique could detect the DNA of a single second-stage juvenile(J_(2))and 10^(-4)***,this PCR technique could be used to detect directly *** from soil *** rapid,sensitive and specific PCR molecular detection technique could be used for the direct identification of a single J_(2)of *** and the detection of *** in mixed nematode populations and the detection of two J_(2)s or one male in 0.5 g soil samples,which will provide technical support for the investigation of the occurrence and damage of *** and the formulation of efficient green co ntrol strategies.

关键词： Meloidogyne vitis PCR rapid detection reliability specificity sensitivity

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Variation and driving factors of nitrous oxide emissions from irrigated paddy field in the arid and semiarid region

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International Soil and Water Conservation Research 2018年第3期6卷 245-252页

作者： Qingwen Zhang Hui Zhang Xingren Liu Aiping Zhang Meijia Xiao Zhengli Yang Agricultural Clean Watershed Research Group Institute of Environment and Sustainable Development in AgricultureCAASBeijing100081China Ningxia vocational and technical college Yinchuan750002China

Agricultural pollution source as Nitrous oxide (N2O) emission from irrigated paddy field as affected by overuse of chemical fertilizer application and flooding irrigation is the primary anthropogenic source of nitrogen (N) losses in the Ningxia irrigation district. The emissions variation and driving factors of N2O emission in the large irrigation districts needs much more investigation. A static chamber-gas chromatograph method was conducted to quantify N losses from a paddy field in Lingwu Farm during 2009– 2010. Three nitrogen (N) treatments were conducted, including the conventional N application rate of 300 kg ha-1 (N300), the reducing N application rate of 240 kg ha-1 (N240) and control plot (N0). The N2O emissions due to combined effects of the fertilizer application and flood irrigation after winter dry follow was 2.86–3.27 kg ha-1 in N300. The flood irrigation at the beginning of the rice transplanting promotes N2O emissions due to nitrification–denitrification of a richer N source provided by the N fertilizer accumulation of soil NH4 + and NO3 -. During the rice growth stage when the paddy field was submerged, N2O emission was very low while intermittent irrigation before tillering and the maturation stages, frequent alteration of dry and wet soil condition enhance N2O emission. The reducing N fertilizer application improved the recovery rate in rice and resulted in a less N2O emission from irrigated paddy field in the arid and semiarid region while keeping the rice yield.

关键词： N2O emission Irrigated paddy field Flood irrigation Anthropogenic-alluvial alkaline soil

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Analysis of the Genetic Diversity and Origin of Some Chinese Domestic Duck Breeds

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Journal of Integrative agriculture 2014年第4期13卷 849-857页

作者： ZHANG Yang CHEN Yang ZHEN Ting HUANG Zheng-yang CHEN Chang-yi LI Xin-yu DUAN Xiu-jun DONG Biao XU Qi CHEN Guo-hong college of Animal Science and Technology Yangzhou University college of Animal Science and Technology Jiangxi Agricultural University vocational and technical college of Jiangsu Animal Husbandry and Veterinary college

Twelve fluorescence-labeled microsatellite markers were used to analyze the genetic diversity of 12 domestic duck breeds and 2 wild duck breeds to determine the relationship and origin of Chinese domestic duck breeds. Gene frequency, effective number of alleles （Ne）, expected heterozygosity （He）, polymorphism information contents （PIC）, inbreeding coefficient in population （Fis）, standard genetic distance （Ds）, and genetic distance （DA） were calculated by FSTAT and distance and phylogenetic analysis after the dates which were output from the Microsatellite-Toolkit software. Genetic distances between 12 domestic duck breeds and 2 wild duck breeds were analyzed by variance analysis. Unweighted pair group method with arithmetic mean （UPGMA） and phylogenetic trees used for cluster analysis were structured. The results indicated that 11 loci had medium- or high-level genetic diversity among the 12 loci, which could be efficiently used in the detection of the genetic parameters of each population. The values of He were 0.5414 to 0.7343, those of PIC proved similar, and those of Fis were 0.1101 to 0.3381 among all populations. All breeds were clustered into three groups by UPGMA phylogenetic trees. Banzui duck was clustered into a separate group. Differences of the DA were analysed by t-test. The results showed that difference in DA between the 12 domestic duck breeds and Lvtou duck and the Banzui duck were very significant （P〈0.01）, indicating that these 12 domestic duck breeds originated from Lvtou wild duck, but not Banzui duck.

关键词： wild duck Chinese domestic duck origin microsatellite DNA marker cluster analysis

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The Effect of Myostatin mRNA Expression on Carcass Traits in yunnan Wuding Chicken

The Effect of Myostatin mRNA Expression on Carcass Traits in...

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2015中国遗传学会大会

作者： Lixian Liu Tengfei Dou Hua Rong Huiquan Tong Dahai Gu Zhiqiang Xu Qihua Li Junjing Jia Changrong Ge college of Animal Science and Technology Yunnan Agricultural University yunnan vocational and technical college of agriculture college of Food Science Yunnan Agricultural University

Introduction Muscle tissue is the largest tissue in the body and it may directly influence whole body *** growth is regulated by the myostatin gene(MSTN).In chicken the correlation between the expression of the myosta... 详细信息

关键词： Myostatin Carcass traits yunnan wuding chicken

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