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Journal of Arid Land 2020年第2期12卷 215-226页

作者： LIU Weichao FU Shuyue YAN Shengji REN Chengjie WU Shaojun DENG Jian LI Boyong han Xinhui YANG Gaihe College of Agronomy Northwest A&F UniversityYangling 712100China research Center of Recycle agricultural Engineering and Technology of Shaanxi Province Yangling 712100China School of Life Science Yan'an UniversityYan'an 716000China

Succession is one of the central themes of ecology;however,the relationship between aboveground plant communities and underground soils during secondary succession remains *** this study,we investigated the composition of plant community,plant-soil C:N:P stoichiometry and their relationships during secondary succession after the abandonment of farmlands for 0,10,20,30,40 and 50 a in China,*** showed that the composition of plant communities was most diverse in the farmlands after secondary succession for 20 and 50 *** organic carbon and total nitrogen contents slightly decreased after secondary succession for 30 a,but both were significantly higher than those of control farmland(31.21%-139.10%and 24.24%-121.21%,respectively).Moreover,C:N ratios of soil and microbe greatly contributed to the changes in plant community composition during secondary succession of abandoned farmlands,explaining 35.70%of the total ***,soil C:N ratio was significantly and positively related with the Shannon-Wiener *** study provides the evidence of synchronous evolution between plant community and soil during secondary succession and C:N ratio is an important linkage between them.

关键词： C:N ratio soil nutrient plant community restoration loess hilly region

PORK PRODUCTION SYSTEMS IN CHINA:A REVIEW OF THEIR DEVELOPMENT,CHALLENGES AND PROSPECTS IN GREEN PRODUCTION

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Frontiers of agricultural Science and Engineering 2021年第1期8卷 15-24页

作者： Shuai ZhanG Xin WU Dandan han Yong HOU Jianzhuang TAN Sung Woo KIM Defa LI Yulong YIN Junjun WANG State Key Laboratory of Animal Nutrition Ministry of Agriculture and Rural Affairs Feed Industry CentreCollege of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China Key Laboratory of Agro-ecological Processes in the Subtropical region Institute of Subtropical Agriculturethe Chinese Academy of SciencesNational Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry ProductionHunan Provincial Engineering Research Center for Healthy Livestock and Poultry ProductionScientific Observation and Experimental Station of Animal Nutrition and Feed Science in the South-Central RegionMinistry of Agriculture and Rural AffairsChangsha 410125China College of Resources and Environmental Sciences National Academy of Agriculture Green DevelopmentKey Laboratory of Plant-Soil Interactions(Ministry of Education)China Agricultural UniversityBeijing 100193China Tech-bank Food Co. LtdNanjing 211800China Department of Animal Science College of Agriculture and Life SciencesNorth Carolina State UniversityRaleighNC 27695USA

This paper reviews the changes in pork production in China,the largest pork producing and consuming nation in the *** pork sector in China has changed dramatically since the 1990s,with large-scale intensive pork production systems replacing the former,exclusively family-based pork production *** breeding,feeding,vaccinating,and management technologies are widely used ***,smallholders still account for a large proportion of the total *** intensification and specialization of the pork sector is expected to continue in the future,but there is increasing awareness and pressure to develop more environmentally-sustainable production *** relative shortage of domestically produced feed,the low utilization efficiency of feed ingredients,the large emissions of nitrogen and phosphorus to the environment,the high use of antibiotics,and the presence of residual metals in manures are very large challenges for the pork sector *** solve these problems,techniques including new feed resource utilization,precise feeding,low-protein diets,alternatives to antibiotics and increased manure recycling are all important topics and research directions *** new techniques and management approaches,it is possible to build more sustainable pork production systems in China.

关键词： China feed pork production sustainability

The LTR of endogenous retrovirus ev21 retains promoter activity and exhibits tissue specific transcription in chicken

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Chinese Science Bulletin 2009年第24期54卷 4664-4670页

作者： LU XiaoQing han JinRun LIU XiaoFang LIN TongHui LI YuLin HU XiaoXiang LI Ning State Key Laboratory of Agrobiotechnology College of Biological Sciences China Agricultural University Beijing 100193 China College of Animal Science & Technology China Agricultural University Beijing 100193 China

Endogenous viruses integrate into the host genome and influence the expression of neighboring genes through their long terminal repeats (LTRs). In this study, we analyzed the promoter, enhancer and transcriptional activities of the chicken endogenous retrovirus ev21 LTR. The LTR was cloned into pGL3-basic and pGL3-promoter luciferase vectors in forward and reverse orientation separately. The luciferase activities were detected respectively in chicken embryonic fibroblast cell, human embryonic kidney cell line, human lung carcinoma cell line, Chinese hamster ovary cell line, and murine melanoma cell line. Relative luciferase activity analysis indicated that the ev21 LTR retained bi-directional promoter activity but no detectable enhancer activity in these cells. The constructs containing the LTR and F1 region show stronger promoter activity than the constructs containing only LTR. The transcriptional pattern of ev21 LTR varied in tissues of late feathering White Leghorn chicken at post-hatch day one. Skin exhibits the highest expression in the tissues examed. Collectively, our results indicate that the ev21 LTR exhibits tissue-type specific expression in White Leghorn chicken, and it also have regulatory potential.

关键词：内源性逆转录病毒启动子活性白来航鸡组织特异性展品铁胚胎成纤维细胞宿主基因组

Effects of wind guide plates on wind velocity acceleration and dune leveling： a case study in Ulan Buh Desert, China

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Journal of Arid Land 2017年第5期9卷 743-752页

作者： han Yanlong GAO Yong MENG Zhongju DANG Xiaohong JIA Xu DING Yanlong LI Peng College of Desert Control Science and Engineering Inner Mongolia Agricultural University Huhhot 010018 China

The areas used to be covered by shifting sand dunes have been reclaimed rapidly in recent years. However, it is a challenge to reclaim high sand dunes because it is rather costly to level the high dunes to gentle arable lands. In this study, a wind guide plate was used to change the characteristics of natural wind to level the sand dunes. The use of wind energy could significantly increase the efficiency of dune leveling and decrease the cost. Low wind velocity is a typical characteristic in Ulan Buh Desert of China where the average wind speed is much lower than the threshold velocity for sand movement. The experiment of this study was conducted to accelerate the wind velocity by a wind guide plate to level a sand dune. Results show that the threshold velocity for sand movement is 3.32 m/s at 10 cm above the sand surface in Ulan Buh Desert. A wind guide plate set at an angle less than 50° could significantly increase the wind velocity. The wind velocity could be accelerated up to the threshold velocity for sand movement behind a plate when the plate is at the angles of 20°, 25°, 35° and 40°. The most significant acceleration of wind velocity appears at 1.5 and 3.0 m behind the plate with an angle of 25°. An obvious wind velocity acceleration zone exists behind the wind guide plate when the angles are at 25°, 35°, 40° and 45°, with the most obvious zone under the angle of 45°. The results also show that the total amount of sand transferred over the experimental period increased by 6.1% under the effects of wind guide plates compared to the sand moved without wind guide plates. The results of the study will provide theoretical and practical supports for desert management in sand dune areas.

关键词： wind guide plate sand dune dune leveling wind velocity sandy desert Ulan Buh Desert

Impacts of native vegetation on the hydraulic properties of the concentrated flows in bank gullies

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Journal of Mountain Science 2021年第4期18卷 907-922页

作者： SU Zheng-an HE Zhou-yao ZHOU Tao WANG Jun-jie WANG Xiao-yi WANG Li-juan FANG Hai-dong SHI Liang-tao LIU Yi-han WU Zuo Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China Forestry College Sichuan Agricultural UniversityChengdu 611130China University of Chinese Academy of Sciences Beijing 100049China College of Water Conservancy and Hydropower Engineering Sichuan Agricultural UniversityYa’an 625014China lnstitute of Tropical Eco-agricultural Sciences Yunnan Academy of Agricultural SciencesYuanmou 651300China College of Geography and Resources Science Sichuan Normal UniversityChengdu 610101China

To quantify the impacts of native vegetation on the spatial and temporal variations in hydraulic properties of bank gully concentrated flows,a series of in situ flume experiments in the bank gully were performed at the Yuanmou Gully Erosion and Collapse Experimental Station in the dry-hot valley region of the Jinsha River,Southwest *** experiment involved upstream catchment areas withone-and two-year native grass(Heteropogon contortus)and bare land drained to bare gully headcuts,i.e.,Gullies 1,2 and *** Gully 4,Heteropogon contortus and Agave sisalana were planted in the upstream catchment area and gully bed,*** these experiments,the sediment concentration in runoff in Gully 3 was the highest and that in Gully 2 was the lowest,clearly indicating that the sediment concentration in runoff obviously decreased and the deposition of sediment obviously increased as the vegetation cover *** concentrated flows were turbulent in response to the flow *** concentrated flows in the gully zones with native grass and bare land were sub-and supercritical,*** flow rate and shear stress in Gully 3 upstream catchment area were highest among the four upstream catchment areas,while the flow rate and shear stress in the gully bed of Gully 4 were lowest among the four gully beds,indicating that native grass notably decreased the bank gully flow rate and shear *** Darcy–Weisbach friction factor(resistance f)and flow energy consumption in the gully bed of Gully 4 were notably higher than those in the other three gully beds,clearly indicating that native grass increased the bank gully surface resistance and flow energy *** Reynolds number(Re),flow rate,shear stress,resistance f,and flow energy consumption in the gully beds and upstream areas increased over time,while the sediment concentration in runoff and Froude number(Fr)***,increasing vegetation cover in upstream catchment areas and downstream gully

关键词： Soil erosion Indigenous grass species Bank gully Concentrated flows Flow energyconsumption Dry and hot valley

A fast technique for visual screening of wheat haploids generated from TaMTL-edited mutants carrying anthocyanin markers

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Plant Communications 2023年第3期4卷 11-13页

作者： Huali Tang Ke Wang Shuangxi Zhang Zhiyang han Yanan Chang Yuliang Qiu Mei Yu Lipu Du Xingguo Ye Institute of Crop Sciences Chinese Academy of Agricultural SciencesBeijing 100081China Crop research Institute Ningxia Academy of Agriculture and Forestry SciencesYinchuan 750002China College of Agronomy Ningxia UniversityYinchuan 750021China

Dear Editor,Breeding a new wheat variety using traditional methods typically takes at least 8 to 10 years,and the breeding period can be dramatically shortened via a doubled haploid strategy,which can yield homozygotes within one or two *** the past several decades,wheat haploids have been widely induced through anther or microspore culture and chromosome elimination via interspecific hybridization between wheat and *** first technique exhibits strong genotype dependency and a severe albino phenomenon,whereas the latter shows low induction efficiency(Sangam et al.,2015).In addition,haploid induction procedures using the aforementioned methods are complicated to perform and require specialized equipment and environmentally controlled ***,the application of these technologies in wheat breeding has been limited(Sangam et al.,2015).

关键词： breeding wheat doubled

Image segmentation of overlapping leaves based on Chan–Vese model and Sobel operator

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Information Processing in Agriculture 2018年第1期5卷 1-10页

作者： Zhibin Wang Kaiyi Wang Feng Yang Shouhui Pan Yanyun han Beijing research Center for Information Technology in Agriculture Beijing 100097China National Engineering research Center for Information Technology in Agriculture Beijing 100097China Key Laboratory of Agri-informatics Ministry of Agriculture of ChinaBeijing 100097China School of Economics&Management China Agricultural UniversityBeijing 100083China

To improve the segmentation precision of overlapping crop leaves,this paper presents an effective image segmentation method based on the Chan–Vese model and Sobel *** approach consists of three ***,a feature that identifies hues with relatively high levels of green is used to extract the region of leaves and remove the ***,the Chan–Vese model and improved Sobel operator are implemented to extract the leaf contours and detect the edges,***,a target leaf with a complex background and overlapping is extracted by combining the results obtained by the Chan–Vese model and Sobel *** verify the effectiveness of the proposed algorithm,a segmentation experiment was performed on 30 images of cucumber *** mean error rate of the proposed method is 0.0428,which is a decrease of 6.54%compared with the mean error rate of the level set *** results show that the proposed method can accurately extract the target leaf from cucumber leaf images with complex backgrounds and overlapping regions.

关键词： Leaf segmentation Sobel operator Overlapping leaves Chan–Vese model Image fusion

Substitution of ramie (Boehmeria nivea) for alfalfa in improving the carcass and meat quality of Liuyang Black goats

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Animal Nutrition 2021年第3期7卷 688-694页

作者： Shaoxun Tang Yao He Peihua Zhang Jinhe Kang Qiongxian Yan Xuefeng han Zhiliang Tan Hongrong Wang Duanqin Wu Lihuai Yu Min Wang Chuanshe Zhou Jinzhen Jiao CAS Key Laboratory for Agro-Ecological Processes in Subtropical region National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry ProductionHunan Provincial Key Laboratory of Animal Nutritional Physiology and Metabolic ProcessSouth-Central Experimental Station of Animal Nutrition and Feed Science in the Ministry of AgricultureInstitute of Subtropical AgricultureThe Chinese Academy of SciencesChangshaHunan410125China College of Animal Science and Technology Yangzhou UniversityYangzhouJiangsu225009China Institute of Bast Fiber Crops Chinese Academy of Agricultural SciencesChangshaHunan410205China College of Animal Science and Technology Hunan Agricultural UniversityChangshaHunan410128China

Ramie(Boehmeria nivea)is noted for the production of a large biomass that has a high protein content and is rich in *** may thus serve as a high-quality forage material to replace alfalfa and improve the meat quality of farmed *** this study,we evaluated the carcass characteristics and meat quality of goats when 0,35%,75%,and 100%of dietary alfalfa was replaced with *** protein content(linear,P<0.0001)and key muscle color values at 24 h after slaughter decreased with increasing ramie *** content of most individual amino acids,non-essential amino acids(NEAA),total amino acids(TAA),branched chain amino acids(BCAA),functional amino acids(FAA),and flavor amino acids(DAA)decreased(P<0.05)with increasing dietary *** diet in which 35%of alfalfa was replaced with ramie yielded meat with the highest amino acid content,whereas the fatty acid profile was unaffected by the inclusion of *** results indicate that ramie could be used as a potential dietary forage resource for goats,and that substituting 35%of alfalfa with ramie,which is equivalent to 126 g/kg DM content,would be optimal in terms of goat meat quality.

关键词： Goat Meat quality Ramie Alfalfa Carcass

Evaluation of the chemical profile from four germplasms sources of Pruni Semen using UHPLC-LTQ-Orbitrap-MS and multivariate analyses

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Journal of Pharmaceutical Analysis 2022年第5期12卷 733-742页

作者： Zihan Zhao Yue Liu Yushi Zhang Zeyu Geng Rina Su Lipeng Zhou Chao han Zhanjun Wang Shuangcheng Ma Weidong Li School of Chinese Materia Medica Beijing University of Chinese MedicineBeijing102488China Institute of Forestry and Grassland Ecology Ningxia Academy of Agricultural and Forestry SciencesYinchuan750002China Institute for Control of Chinese Traditional Medicine and Ethnic Medicine National Institutes for Food and Drug ControlBeijing100050China

Pruni Semen,the seed of several unique Prunus plants,is a traditional purgative herbal *** determine the authentic sources of Pruni Semen,46 samples from four species were collected and *** compounds including multiflorin A(Mul A),a notable purative compound,were isolated and identified by chemical separation and nuclear magnetic resonance ***-six communal components were identified by ultra-high performance liquid chromatography with linear ion trap-quadrupole Orbitrap mass spectrometry,and acetyl flavonoid glycosides were recognized as characteristic *** flavonoids were distributed in the seed coat and cyanogenic glycosides in the *** on this,methods for identifying Pruni Semen from different sources were established using chemical fingerprinting,quantitative analysis of the eight principal compounds,hierarchical cluster analysis,principal component analysis,and orthogonal partial least squares discriminant *** results showed that the samples were divided into two categories:one is the small seeds from Prunus humilis(Ph)and Prunus japonica(Pj),and the other is the big seeds from Prunus pedunculata(Pp)and Prunus triloba(Pt).The average content of Mul A was 3.02,6.93,0.40,and 0.29 mg/g,while the average content of amygdalin was 18.5,17.7,31.5,and 30.9 mg/g in Ph,Pj,Pp,and Pt,*** the above information suggests that small seeds might be superior sources of Pruni *** is the first comprehensive report on the identification of chemical components in Pruni Semen from different species.

关键词： Pruni semen Acetyl flavonoids Amygdalin Multivariate analyses Authentic sources

Differential transcriptional regulation of the NANOG gene in chicken primordial germ cells and embryonic stem cells

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Journal of Animal Science and Biotechnology 2021年第3期12卷 877-890页

作者： Hee Jung Choi So Dam Jin Deivendran Rengaraj Jin Hwa Kim Bertrand Pain Jae Yong han Department of agricultural Biotechnology and research Institute of Agriculture and Life Sciences Seoul National UniversitySeoul 08826South Korea Univ Lyon UniversitéLyon 1INSERMINRAEStem Cell and Brain Research InstituteU1208USC136169500 BronFrance Institute for Biomedical Sciences Shinshu UniversityMinamiminowaNagano 399-4598Japan

Background:NANOG is a core transcription factor(TF)in embryonic stem cells(ESCs)and primordial germ cells(PGCs).Regulation of the NANOG gene by TFs,epigenetic factors,and autoregulatory factors is well characterized in ESCs,and transcriptional regulation of NANOG is well established in these *** NANOG plays a key role in germ cells,the molecular mechanism underlying its transcriptional regulation in PGCs has not been ***,we investigated the mechanism that regulates transcription of the chicken NANOG(cNANOG)gene in PGCs and ***:We first identified the transcription start site of cNANOG by 5′-rapid amplification of cDNA ends PCR ***,we measured the promoter activity of various 5′flanking regions of cNANOG in chicken PGCs and ESCs using the luciferase reporter *** expression required transcriptional regulatory elements,which were positively regulated by POU5F3(OCT4)and SOX2 and negatively regulated by TP53 in *** proximal region of the cNANOG promoter contains a positive transcriptional regulatory element(CCAAT/enhancer-binding protein(CEBP)-binding site)in ***,small interfering RNA-mediated knockdown demonstrated that POU5F3,SOX2,and CEBP played a role in cell type-specific transcription of ***:We show for the first time that different trans-regulatory elements control transcription of cNANOG in a cell type-specific *** finding might help to elucidate the mechanism that regulates cNANOG expression in PGCs and ESCs.

关键词： Chicken Embryonic stem cells NANOG gene Primordial germ cells Regulatory elements