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The Characteristics of Plant Communities Along East Eurasian Steppe Transect

Journal of Integrative agriculture 2014年第6期13卷 1157-1164页

作者： HAN Wen-jun HOU Xiang-yang OLOKHNUUD Chun-liang Michael P Schellenberg Institute of Grassland Research Chinese Academy of Agricultural Sciences Semiarid Prairie agricultural Research Center (SPARC) Agriculture and Agri-Food Canada

The East Eurasian Steppe Transect （EEST） is the ifrst international transect across regions of middle and high latitudes in the eastern Eurasian steppe. The EEST is an ideal platform for researching the response of Eurasian temperate steppe to global change, because of its integrated gradients of temperature and human activities on a large-scale. In this study, basic characteristics of plant communities along the EEST across a latitudinal gradient was analyzed. According to the survey of 58 sampling sites, there are 140 species belonging to 34 families and 94 genera. Of particular note was the ifnding of Astragalus dalaiensis which has disappeared in the grasslands of China. On the whole, Gramineae plants are dominant with Liliaceae plants in the communities signiifcantly decreasing along the latitudinal gradient from south to north. The Shannon-Wiener index and biomass of communities all decreased along the latitudinal gradient with signiifcant negative linear regressions. The SDR2 （summed dominance ratio based on two factors） of dominant plants in the upper layers of communities, such as Stipa and Leymus chinensis, decreased along the latitudinal gradient from south to north. Especially, the SDR2 of L. chinensis decreased signiifcantly. The SDR2 of Cleistogenes squarrosa, Agropyron cristatum in the lower layers of communities and the indicator species for degradation were not affected. Potentilla acaulis was found mainly in the southern and northern areas. Stellera chamaejasme was found just in a few sites in the southern area of the EEST. In communities of Stipa grandis and Stipa krylovii, annual and biennial species are dominant. The ratio of annual and biennial species in the community is signiifcantly related to the latitudinal gradient. Perennial herbaceous plants and shrubs were not affected. According to the principal component analysis （PCA）, with the data from 58＆#215;140 dimensions, the ifrst and second components had the lowest proportion, thus indicati

关键词： climate warming transect typical steppe species diversity summed dominance ratio

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The Stripe Rust Resistance Gene Yr10 Encodes an Evolutionary-Conserved and Unique CC-NBS-LRR Sequence in Wheat

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Molecular Plant 2014年第12期7卷 1740-1755页

作者： Wei Liu Michele Frick Rene Huel Cory L. Nykiforuk Xiaomin Wang Denis A. Gaudet Francois Eudes Robert L. Conner Alan Kuzyk Zhensheng Kang Andre Laroche State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection Northwest A&F University YanglingShaanxi 712100 RR. China agriculture and agri-food canada Lethbridge Research Centre 5403 1st Avenue South Lethbridge Alberta T1J 4B1 Canada Current address: The International Commission on Missing Persons Alipasina 45A Sarajevo 71000 Bosnia and Herzegovina Current address: Emergent BioSolutions 155 Innovation Drive Winnipeg MB R3T 5Y3 Canada Current address: agriculture and agri-food canada Morden Research Centre Unit 100-101 Route 100 Morden MB R6M 1Y5 Canada Retired from agriculture and agri-food canada

The first seedling or all-stage resistance （R） R gene against stripe rust isolated from Moro wheat （Triticum aes- tivum L.） using a map-based cloning approach was identified as Yr10. Clone 4B of this gene encodes a highly evolutionary- conserved and unique CC-NBS-LRR sequence. Clone 4E, a homolog of Yr10, but lacking transcription start site （TSS） and putative TATA-box and CAAT-box, is likely a non-expressed pseudogene. Clones 4B and 4E are 84% identical and divergent in the intron and the LRR domain. Gene silencing and transgenesis were used in conjunction with inoculation with differen- tially avirulent and virulent stripe rust strains to demonstrate Yr10 functionality. The Yr10 CC-NBS-LRR sequence is unique among known CC-NBS-LRR R genes in wheat but highly conserved homologs （E = 0.0） were identified in Aegilops tauschii and other monocots including Hordeum vulgare and Brachypodium distachyon. Related sequences were also identified in genomic databases of maize, rice, and in sorghum. This is the first report of a CC-NBS-LRR resistance gene in plants with limited homologies in its native host, but with numerous homologous R genes in related monocots that are either host or non-hosts for stripe rust. These results represent a unique example of gene evolution and dispersion across species.

关键词： seedling or all-stage stripe rust resistance gene functionality transgenesis gene silencing homolog sequences coiled-coil region nucleot de-b nding site leucine-rich repeat domain.

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Identification and characterization of soybean dreg soluble dietary fibre by combination of extrusion pre-treatment and enzymatic modification

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food Quality and Safety 2017年第2期1卷 153-160页

作者： Min Qu Yujia Liu Guang Zhang Sophia Jun Xue Hongchen Fan Yan Wang Shiyou Yu Key Laboratory of food Science and Engineering of Heilongjiang Province College of Food EngineeringHarbin University of CommerceHarbinChina Guelph food Research Center Agriculture-Agri-Food CanadaGuelphOntarioCanada

OBJECTIVES:Soybean dreg is a by-product of soy milk processing,which contains high levels of soluble dietary fibre(SDF).In this study,we aimed to provide comprehensive processes of pre-treated extrusion for the improving structure and properties of soybean dreg soluble dietary fibre(SDSDF),which would be a valuable approach to enhance physiological ***:Here,we characteristic the functional role of SDSDF employing to extrusion *** dregs were pre-treated using the twin screw extrusion method followed by enzymatic modification using neutral protease,α-amylase,glucoamylase,and cellulose to produce *** physical properties and antioxidant activity of SDSDF were ***:The morphology and crystal structure of SDSDF were observed that,through extrusion processing and enzymatic modification,the SDSDF yield increased by 106.28%.Moreover,the surface structure showed block-shaped or reticular formations in the extruded SDSDF,and the size of block-shaped cells was about 10μ*** spectroscopic analysis showed that a characteristic absorption peak of polysaccharide appeared at 1631 cm−1 during extrusion ***,after extrusion processing,decreased absorption peaks were observed for the extruded ***,XRD analysis showed that the 2θdiffraction peak changed at 24.16°for the extruded ***:The overall findings suggest that the water holding capacity(WHC),oil holding capacity(OHC),expansibility,and the water solubility were significantly decreased in extruded *** addition,the scavenging ability of 1,1-diphenyl-2-picrylhydrazyl(DPPH),-OH,O_(2)^(-),and the total reducing power were significantly improved,indicating that beneficial changes had taken place in the crystal structure of cellulose or hemicellulose to improve the physiological activity in extruded SDSDF.

关键词： Soybean dreg Soluble dietary fibre Extrusion Enzymatic modification

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Residue Return Effects Outweigh Tillage Effects on Soil Microbial Communities and Functional Genes in Black Soil Region of Northeast China

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Chinese Geographical Science 2023年第4期33卷 679-692页

作者： WANG Qian JIA Shuxia LIANG Aizhen CHEN Xuewen ZHANG Shixiu ZHANG Yan Neil B MCLAUGHLIN GAO Yan HUANG Dandan Key Laboratory of Mollisols Agroecology Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China School of Geography Sciences Nanjing Normal UniversityNanjing 210023China College of Forestry Beihua UniversityJilin 132013China University of Chinese Academy of Sciences Bejing 100049China Ottawa Research and Development Centre Agriculture and Agri-Food CanadaOttawa K1A 0C6Canada

Conservation tillage as an effective alternative to mitigate soil degradation has attracted worldwide attention,but the influences of conservation tillage on soil microbial community and especially function remain *** metagenomics sequencing was performed to examine the taxonomic and functional community variations of black soils under three tillage regimes,namely no-tillage with residue(maize straw)return(NTS),moldboard plow with residue return(MPS),and moldboard plow without residue return(MPN)in Northeast *** results revealed:1)Soil bacterial and archaeal communities differed significantly under different tillage regimes in contrast to soil fungal community.2)The overlay of less tillage and residues return under NTS led to unique soil microbial community composition and functional ***,in contrast to other treatments,NTS increased the relative abundances of some taxa such as Bradyrhizobium,Candidatus Solibacter,and Reyranella,along with the relative abundances of some taxa such as Sphingomonas,Unclassified Chloroflexi and Nitrososphaera decreased;NTS had a unique advantage of increasing the relative abundances of genes involved in‘ATP-binding cassette(ABC)transporters’and‘quorum sensing(QS)’pathways,while MPN favored the genes involved in‘flagellar assembly’pathway and some metabolic pathways such as‘carbon’and‘glyoxylate and dicarboxylate’and‘selenocompound’metabolisms.3)Significantly different soil bacterial phyla(Acidobacteria,Gemmatimonadetes,and Chloroflexi)and metabolic pathways existed between MPN and another two treatments(NTS and MPS),while did not exist between NTS and MPS.4)Dissolved organic carbon(DOC)and soil bulk density were significantly affected(P<0.05)by tillage and accounted for the variance both in microbial(bacterial)community structure and functional *** results indicated that a change in tillage regime from conventional to conservation tillage results in a shift of microbial community and

关键词： no-tillage microbial community composition Kyoto Encyclopedia of Genes and Genomes(KEGG)pathways soil properties

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Degradation of ^(14)C-glyphosate and aminomethylphosphonic acid (AMPA) in three agricultural soils

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Journal of Environmental Sciences 2010年第9期22卷 1374-1380页

作者： Abdul Jabbar Al-Rajab Michel Schiavon Laboratory of Soil and Environmental Sciences 54505 Vandoeuvre-lès-Nancy Cedex France agriculture and agri-food canada London Ontario N5V 4T3 Canada

Glyphosate （N-phosphonomethyl glycine） is the most used herbicide worldwide. The degradation of ^14C-labeled glyphosate was studied under controlled laboratory conditions in three different agricultural soils： a silt clay loam, a clay loam and a sandy loam soil. The kinetic and intensity of glyphosate degradation varied considerably over time within the same soil and among different types of soil. Our results demonstrated that the mineralization rate of glyphosate was high at the beginning of incubation and then decreased with time until the end of the experiment. The same kinetic was observed for the water extractable residues. The degradation of glyphosate was rapid in the soil with low adsorption capacity （clay loam soil） with a short half-life of 4 days. However, the persistence of glyphosate in high adsorption capacity soils increased, with half-live of 19 days for silt clay loam soil and 14.5 days for sandy loam soil. HPLC analyses showed that the main metabolite of glyphosate, arninomethylphosphonic acid （AMPA） was detected after three days of incubation in the extracts of all three soils. Our results suggested that the possibility of contamination of groundwater by glyphosate was high on a long-term period in soils with high adsorption capacity and low degrading activities and/or acid similar to sandy loam soil. This risk might be faster but less sustainable in soil with low adsorption capacity and high degrading activity like the clay loam soil. However, the release of non-extractable residues may increase the risk of contamination of groundwater regardless of the type of soil.

关键词： glyphosate aminomethylphosphonic acid (AMPA) mineralization degradation soil

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Identification of the Mamestra configurata （Lepidoptera Noctuidae） peritrophic matrix proteins and enzymes involved in peritrophic matrix chitin metabolism

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Insect Science 2016年第5期23卷 656-674页

作者： Umut Toprak Martin Erlandson Doug Baldwin Steve Karcz Lianglu Wan Cathy Coutu Cedric Gillott Dwayne D. Hegedus agriculture and agri-food canada Saskatoon SK Canada Department of Biology University of Saskatchewan Saskatoon SK Canada Department of Plant Protection Faculty of Agriculture University of Ankara Ankara Turkey Department of food and Bioproduct Sciences University of Saskatchewan Saskatoon SK Canada plant Biotechnology Institute National Research Council of Canada Saskatoon SK Canada

The peritrophic matrix （PM） is essential for insect digestive system physiol- ogy as it protects the midgut epithelium from damage by food particles, pathogens, and toxins. The PM is also an attractive target for development of new pest control strategies due to its per os accessibility. To understand how the PM performs these functions, the molecular architecture of the PM was examined using genomic and proteomic approaches in Mamestra configurata （Lepidoptera： Noctuidae）, a major pest of cruciferous oilseed crops in North America. Liquid chromatography-tandem mass spectrometry analyses of the PM identified 82 proteins classified as：（i） peritrophins, including a new class with a CBDIII domain; （ii） enzymes involved in chitin modification （chitin deacetylases）, di- gestion （serine proteases, aminopeptidases, carboxypeptidases, lipases and ^-amylase） or other reactions （/^-l,3-glucanase, alkaline phosphatase, dsRNase, astacin, pantetheinase）; （iii） a heterogenous group consisting of polycalin, REPATs, serpin, C-Type lectin and Lsti99/Lsti201 and 3 novel proteins without known orthologs. The genes encoding PM proteins were expressed predominantly in the midgut, cDNAs encoding chitin synthase-2 （McCHS-2）, chitinase （McCHI）, and fl-N-acetylglucosaminidase （McNAG） enzymes, in- volved in PM chitin metabolism, were also identified. McCHS-2 expression was specific to the midgut indicating that it is responsible for chitin synthesis in the PM, the only chitinous material in the midgut. In contrast, the genes encoding the chitinolytic enzymes were expressed in multiple tissues. McCHS-2, McCHI, and McNAG were expressed in the midgut of feeding larvae, and NAG activity was present in the PM. This information was used to generate an updated model of the lepidopteran PM architecture.

关键词： chitin Mamestra configurata peritrophic matrix protein

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Effects of Tillage Management on Infiltration and Preferential Flow in a Black Soil, Northeast China

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Chinese Geographical Science 2013年第3期23卷 312-320页

作者： FAN Ruqin ZHANG Xiaoping YANG Xueming LIANG Aizhen JIA Shuxia CHEN Xuewen Northeast Institute of Geography and Agroecology Chinese Academy of Sciences University of Chinese Academy of Sciences Greenhouse and Processing Crops Research Centre Agriculture and Agri-Food Canada

The impacts of no-tillage (NT) and moldboard plough (MP) managements on infiltration rate and preferential flow were characterized using a combined technique of double-ring device and dye tracer on a black soil (Mollisols) in Northeast China. The objective of this study is to evaluate how tillage practices enhance soil water infiltration and preferential flow in favor of soil erosion control in the study area. The steady infiltration rates under NT management are 1.6 and 2.1 times as high as those under MP management in the 6th and 8th years of the tillage management in place, while the infiltrated water amounts under NT management are 1.4 and 2.0 times as high as those under MP management, respectively. The depth of methylene blue penetrated into NT soil increases from 43cm in the 6th year to 57cm in the 8th year, which are 16cm and 19cm deeper than those in MP soil, respectively. The results of morphologic image show that more biological macro-pores occur in NT soil than in MP soil. These macro-pores play a key role in enhancing preferential flow in NT soil, which in turn promotes water infiltration through preferential pathways in NT soil. The results are helpful to policy-making in popularizing NT and have the implications for tillage management in regard to soil erosion control in black soil region of China.

关键词：东北黑土土壤渗透耕作方式优先流中国土壤水分入渗免耕土壤稳定入渗率

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Soil Quality in Relation to agricultural Production in the North China Plain

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Pedosphere 2015年第4期25卷 592-604页

作者： XIA Min ZHAO Bingzi Xiying HAO ZHANG Jiabao State Key Laboratory of Soil and Sustainable agriculture Institute of Soil Science Chinese Academy of Sciences College of Public Administration Nanjing Agricultural University agriculture and agri-food canada Lethbridge Research Centre

Sustainable agricultural production is of vital importance to food supply security. This study aimed to investigate crop yield response to spatial variability of soil quality at a county scale in the North China Plain(NCP) and subsequently derive key soil quality indicators. Soil samples were geo-referenced and taken in 2008 from both surface(0–20 cm) and subsurface(20–40 cm) layers in132 fields throughout the Fengqiu County, located in the centre of the NCP, for subsequent soil properties' analyses. Annual crop yields were obtained from the same fields where soil samples were collected. Soil quality was evaluated based on a fuzzy set with 13 soil properties, and its spatial distributions were investigated by integrating geostatistical analysis and geographic information system(GIS) techniques. Soil quality indices were classified into five grades, and their spatial distributions were mapped within the *** surface soil qualities were about one to two grades higher than the subsurface soil. The quality indices for surface and subsurface soils were positively associated with the annual crop yields, suggesting the importance of both. Soil organic matter, total nitrogen,available P, and available K contributed 50% of the combined weight to the soil quality index and were identified as key indicators of soil quality status in the area in terms of sustainability.

关键词：土壤质量指标华北平原农业生产地理信息系统土壤质量指数作物产量表层土壤空间分布

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The Study on the Effects of Chinese Herbal Mixtures on Growth,Activity of Post-Ruminal Digestive Enzymes and Serum Antioxidant Status of Beef Cattle

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agricultural Sciences in China 2011年第3期10卷 448-455页

作者： WANG Hong-fang YANG Wei-ren WANG Yu-xi YANG Zai-bin CUI Yong-hua DepartmentofAnimalSciencesandTechnology ShandongAgriculturalUniversityTai’an271018P．R．China agriculture and agri-food canada Lethbridge Research Centre Lethbridge AB P.O.Box 3000 Canada

Sixteen Limousin×Luxi crossbred beef cattle [（199.4±8.67） kg] were used to evaluate the effects of Chinese herbal mixtures （CHM） on growth, activities of post-ruminal digestive enzymes and serum antioxidant status of beef cattle. Treatments were control （no CHM supplementation） and three formulations of CHM （CHM-A, CHM-B and CHM-C） that were arranged as completely randomized design. The calves were fed in indoor individual feeding barn with total mixed ration for 90 d. The CHM-A, CHM-B, and CHM-C was incorporated into the diet at the level of 20 g kg-1 DM （dry matter） of concentrate. The cattle were weighted at the beginning, at the end and every 15 d between to determine growth rate. Blood sample was taken every 30 d to analyze activities of total superoxide dismutase （T-SOD） and glutathione peroxidase （GSH-PX） and concentration of malondialdehyde （MDA）. The cattle were slaughtered at the end of experiment and chymus samples from various section of the post-ruminal digestive tract were collected to analyze enzymes activities. All cattle had similar average daily gain, but cattle supplemented with CHM-A tended faster growth （P=0.08） compared to the control and other CHM treatments. Supplementation of CHM did not affect pH of chymus in any section of the post-ruminal digestive tract. Activities of pepsin, trypsin, chymotrypsin, and lipase in chymus samples were enhanced （P0.05） to various extents by supplementation of CHM-A, CHM-B, and CHM-C depending on the enzymes and the site of the digestive tract. Amylase activity was increased only by CHM-A and CHM-C from chymus sample collected at the ileum. Supplementation of CHM-A and CHM-B reduced （P0.05） concentration of MDA, but did not affect GSH-PX activity in the serum of cattle throughout the entire experimental period. Cattle supplemented with CHM-B also had higher （P0.05） T-SOD activity in the serum at day 30 and 60 as compared with the control and the other two CHM treatments. Chinese herbal mixtures supplemented a

关键词： Chinese herbal mixture cattle growth digestive enzymes antioxidant status

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Effects of broad-leaf crop frequency in various rotations on soil organic C and N, and inorganic N in a Dark Brown soil

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agricultural Sciences 2012年第6期3卷 854-864页

作者： Sukhdev S. Malhi R. L. Lemke S. A. Brandt agriculture and agri-food canada Melfort Saskatchewan Canada agriculture and agri-food canada Saskatoon Saskatchewan Canada agriculture and agri-food canada Scott Saskatchewan Canada

The objective of this study was to determine the impact of frequency of broad-leaf crops canola and pea in various crop rotations on pH, total organic C (TOC), total organic N (TON), light fraction organic C (LFOC) and light fraction organic N (LFON) in the 0 - 7.5 and 7.5 - 15 cm soil depths in autumn 2009 after 12 years (1998-2009) on a Dark Brown Chernozem (Typic Boroll) loam at Scott, Saskatchewan, canada. The field ex-periment contained monoculture canola (herbicide tolerant and blackleg resistant hybrid) and monoculture pea compared with rotations that contained these crops every 2-, 3-, and 4-yr with wheat. There was no effect of crop rotation duration and crop phase on soil pH. Mass of TOC and TON in the 0 - 15 cm soil was greater in canola phase than pea phase in the 1-yr (monoculture) and 2-yr crop rotations, while the opposite was true in the 3-yr and 4-yr crop rotations. Mass of TOC and TON (averaged across crop phases,) in soil generally increased with increasing crop rotation duration, with the maximum in the 4-yr rotation while no difference in the 1-yr and 2-yr rotations. Mass of LFOC and LFON in soil was greater in canola phase than pea phase in the 1-yr, 2-yr and 3-yr rotations, but the opposite was true in the 4-yr rotation. There was no consistent effect of crop rotation duration on mass of LFOC and LFON. The N balance sheet over the 1998 to 2009 period indicated large amounts of unaccounted N for monoculture pea, suggesting a great potential for N loss from the soil-plant system in this treatment through nitrate leaching and/or denitrification. In conclusion, the findings suggest that the quantity of organic C and N can be maximized by increasing duration of crop rotation and by including hybrid canola in the rotation.

关键词： Broad-Leaf Crops Canola Frequency Light Fraction Organic C Light Fraction Organic N Pea Total Organic C Total Organic N

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