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Integrating MODFLOW and GIS technologies for assessing impacts of irrigation management and groundwater use in the Hetao Irrigation District,Yellow River basin

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Science china(Technological Sciences) 2009年第11期52卷 3257-3263页

作者： XU Xu1,2. HUANG GuanHua1,2.& QU ZhongYi3 1 center for Agriculture Water Research, china agricultural university, Beijing 100083,{2. 2.Chinese-Israeli International center for Research and Training in Agriculture, china agricultural university, Beijing 100083,{2. 3 Water Conservancy and Civil Engineering College, Inner Mongolia {6. university, Hohhot 010018,{2. 1. center for Agriculture Water Research China Agricultural University Beijing 100083 China 2. Chinese-Israeli International center for Research and Training in Agriculture China Agricultural University Beijing 100083 China 3. Water Conservancy and Civil Engineering College Inner Mongolia Agricultural University Hohhot 010018 China

Due to severe water scarcity, water resources used in agricultural sector have been reduced markedly in Hetao irrigation district. Application of water-saving practices (WSPs) is required for the sustainable agricultural development. The human activities including WSPs and increase of groundwater abstraction can lower down the groundwater table, which is helpful to the salinity control. Meanwhile, an excessively large groundwater table depth may result in negative impact on crop growth and fragile ecological environment. In this paper, the Jiefangzha irrigation system in Hetao irrigation district was selected as a typical area, a groundwater flow model based on ArcInfo Geographic Information System (GIS) was developed and implemented to quantify the effect of human activities on the groundwater system in this area. The preand post-processing of model data was performed efficiently by using the available GIS tools. The time-variant data in boundary conditions was further edited in Microsoft Excel with programs of Visual Basic for Application (VBA). The model was calibrated and validated with independent data sets. Application of the model indicated that it can well describe the effect of human activities on groundwater dynamics in Jiefangzha irrigation system.

关键词： groundwater flow modeling MODFLOW GIS water-saving practices irrigation district

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Genetic analysis on 3'- terminal flanking region of uncoupling protein 3 in different pig breeds

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Chinese Science Bulletin 2002年第18期47卷 1541-1543页

作者： FANG Meiying, ZHAO Xingbo, LI Ning & WU ChangxinCollege of Animal Science and Technology, china agricultural university, Beijing 100094,{2. State Key Laboratory for Agrobiotechnology, china agricultural university, Beijing 100094,{2. College of Animal Science and Technology China Agricultural University Beijing China State Key Laboratory for Agrobiotechnology China Agricultural University Beijing China

The 3’-terminal flanking region of porcine uncoupling protein 3 (UCP3) was cloned, the sequence data revealed 15 nucleotide substitutions among Landrace and three Chinese native pig breeds named Neijiang, Minpig and Erhualian. The continuous 9 polymorphic sites were checked by PCR-RFLP, the results indicated that Erhualian had extraordinary gene frequency, presented most significant difference by x2.test compared with Landrace, Largewhite, Neijiang and Minpig respectively, significant level compared with Meishan; and Meishan also had significant difference compared with Landrace and Minpig respectively. These results can be concluded that Taihu pigs have special genetic characteristics among pig breeds.

关键词： pig uncoupling protein gene clone PCR-RFLP.

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Genetic analysis of segregation distortion of mating-type factors in Lentinula edodes

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Progress in Natural Science:Materials International 2005年第8期15卷 684-688页

作者： CHENG Shuiming 1,2. LIN Fanxue1, XU Xuefeng1, LI Anzheng1 and LIN Fangcan1*(1. State Key Laboratory of agricultural Microbiology and Institute of Applied Mycology, Huazhong agricultural {2., Wuhan 430070, china 2. National Engineering Research center For Wheat, Henan agricultural {2., Zhengzhou 450002. china) State Key Laboratory of agricultural Microbiology and Institute of Applied Mycology Huazhong Agricultural University Wuhan 430070 China. National Engineering Research center For Wheat Henan Agricultural University Zhengzhou 450002 China

Analyses of the mating-type ratio of protoplast monokaryons to spores in 2. strains of Lentinula edodes were performed through statistical methods. The results showed that the segregation distortion phenomenon commonly exists in both types of Lentinula edodes, 17 out of the 2. samples did not display the expected 1∶1 ratio of protoplast monokaryons; and among them 8 fruiting strains distorted 1∶1∶1∶1 segregation of spores. The degree of distortion in all tested wild strains was significantly lower than that of cultured strains. In fruiting test of positive-negative parent, predominant spores were those with the mating type identical to dikaryotic parent, indicating that the predominance of nuclei mainly depends on the mating type of dikaryotic parent. Data from di-mon mating test verified that monokaryons with acceptor nuclear type are present exclusively in a large amount after dedikaryotization, suggesting that the specificities among B factors and some other unknown factors in cytoplasm are probably responsible for the phenomenon of skewed segregation.

关键词： Lentinula edodes mating-type factors segregation distortion cytoplasm.

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Tn5-mutagenesis and identification of atr operon and trpE gene responsible for indole-3-acetic acid synthesis in Azospirillum brasilense Yu6.

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Progress in Natural Science:Materials International 2006年第4期16卷 366-372页

作者： XIE Baoen and CHEN Sanfeng State Key Laboratory for Agrobiotechnology, College of Biological Sciences, china agricultural university, Beijing 100094,{2. State Key Laboratory for Agrobiotechnology College of Biological Sciences China Agricultural University Beijing 100094 China

To bring more information about synthesis of indole-3-acetic acid (IAA) from Azospirillum brasilense, a Tn5-insertion library of A. brasilense Yu6. was constructed and subjected to screening for IAA producing mutants. Two mutants with decreased IAA levels, named as A3 and A2., were isolated. The sequence analysis of loci tagged showed that the Tn5-106.a was located in the atrA gene encoding GntR family transcriptional regulator and trpE gene encoding component I of anthranilate synthase respectively. At the same time. atrB encoding phosphotransferase and atrC encoding aminotransferase were cloned downstream the atrA gene and atrA, atrB and atrC were clustered in an operon. Mutagenesis and complementation studies showed that atrA and atrC were involved in IAA synthesis. IAA levels of trpE mutant and wild-type strain could be improved by adding anthranilate into the medium.

关键词： indole-3-acetic acid (IAA) IAA mutants Azospirillum brasilense atrABC cluster trpE Tn5 transposon.

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Effect of Soil Moisture on Release of Low-Molecular Weight Organic Acids in Root Exudates and the Accu-mulation of Iron in Root Apoplasm of Peanut

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Pedosphere 2000年第4期10卷 333-338页

作者： ZHENG YI and ZHANG FUSUO (Department of Plant Nutrition, china agricultural university, Beijing,100094{2.) 中国农业大学北京 100094

A three-compartments rhizobox was designed and used to study the low-molecular-weight organic acids in root exudates and the root apoplastic iron of "lime-induced chlorosis" peanut grown on a calcareous soil in relation to different soil moisture conditions. Results showed that chlorosis of peanuts developed under condition of high soil moisture level (2.0 g kg-1), while peanuts grew well and chlorosis did not develop when soil moisture was managed to a normal level (150 g kg-1). The malic acid, maleic acid and succinic acid contents of chlorotic peanut increased by 108.72., 0.02. and 2..446.ig cm-2. respectively, compared with healthy peanuts. The content of citric acid and fumaric acid also increased in root exudates of chlorotic peanuts. On Days 2. and 42.of peanut growth, the accumulation of root apoplastic iron in chlorotic peanuts was higher than that of healthy peanuts. From Day 2. to Day 42. the mobilization percentages of chlorotic peanuts and healthy peanuts to root apoplastic iron were almost the same, being 52.4% and 52.8%, respectively, indicating that the chlorosis might be caused by the inactivation of iron within peanut plant grown on a calcareous soil under high soil moisture conditions.

关键词： apoplastic iron peanut root exudates soil moisture

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Pattern phenomena in an rf discharge dusty plasma system

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Science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 588-596页

作者： HUANG Feng1,2. YE Maofu2.& WANG Long2.1. College of Science, china agricultural university, Beijing 100083, china 2. Institute of Physics, Chinese Academy of Sciences, Beijing 100080, china 1. College of Science China Agricultural University Beijing 100083 China 2. Institute of Physics Chinese Academy of Sciences Beijing 100080 China

Various dust patterns are observed in an rf discharge dusty plasma system. According to the dust growth process from small to large in size, the formation of different dust patterns can be divided into two stages: the small-particle stage (or dust cloud stage), and the large-particle stage (or dust crystal stage). The evolution relations between different dust patterns with gas pressure changing are investigated. Dust voids, dust acoustic waves and strong turbulence modes are presented at the small-particle stage. The self-organized dust lattices and dust clusters are investigated at the large-particle stage. The static structure of a dust lattice is characterized by means of the pair correlation function. Dust clusters formed by particles with different numbers and the regular evolution of the clusters with gas pressure are also investigated. The packing sequences of dust clusters are verified through two-dimensional confined molecular dynamics simulations.

关键词： dusty plasma dust patterns

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Aberrant histone H4 acetylation in dead somatic cell-cloned calves

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Progress in Natural Science:Materials International 2008年第7期18卷 813-818页

作者： Lei Zhang a,b,*, Shaohua Wang a, Qiang Li a, Xiangdong Ding c, Yunping Dai a, Ning Li a,* a State Key Laboratory for Agrobiotechnology, china agricultural university, Beijing 100094,{2. b Beijing Gene & Protein Biotechnology Co. LTD, Beijing 100094,{2. c College of Animal Science and Technology, china agricultural university, Beijing 100094,{2. State Key Laboratory for Agrobiotechnology China Agricultural University Beijing 100094 China Beijing Gene & Protein Biotechnology Co. LTD Beijing 100094 China College of Animal Science and Technology China Agricultural University Beijing 100094 China

In somatic cell-cloned animals, inefficient epigenetic reprogramming can result in an inappropriate gene expression and histone H4 acetylation is one of the key epigenetic modifications regulating gene expression. In this study, we investigated the levels of histone H4 acetylation of 11 development-related genes and expression levels of 19 genes in lungs of three normal control calves and nine aber- rant somatic cell-cloned calves. The results showed that nine studied genes had decreased acetylation levels in aberrant clones (p 0.05). Whereas 13 genes had significantly decreased expression (p 0.05), and only one gene had higher expression level in clones (p < 0.05). Furthermore, FGFR, GHR, HGFR and IGF1 genes showed lowered levels of both histone H4 acetylation and expression in aberrant clones than in controls, and the level of histone H4 acetylation was even more lowered in aberrant clones than those in controls. It was suggested that the lower levels of histone H4 acetylation in aberrant clones caused by the previous memory of cell differentiation might not support enough chromatin reprogramming, thus affecting appropriate gene expressions, and growth and development of the cloned calves. To our knowledge, this is the first study on how histone H4 acetylation affects gene expression in organs of somatic cell-cloned calves.

关键词： Somatic cell-cloned calves Histone H4 acetylation Gene expression Lungs

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Phototoxic effect of UVR on wild type, ebony and yellow mutants of Drosophila melanogaster: Life Span, fertility, courtship and biochemical aspects

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Science china(Life Sciences) 2008年第10期51卷 885-893页

作者： WANG ZhePeng1,2. LIU RuiFang2. WANG AnRu3, DU LiLi1 & DENG XueMei1 1 College of Animal Science and Technology, china agricultural university, Beijing 100094,{2. 2.Vocational and Technologic College, Inner Mongolia Agriculture university, Baotou 014109,{2. 3 College of Veterinary Medicine, china agricultural university, Beijing 100094,{2. 1. College of Animal Science and Technology China Agricultural University Beijing 100094 China 2. Vocational and Technologic College Inner Mongolia Agriculture University Baotou 014109 China 3. College of Veterinary Medicine China Agricultural University Beijing 100094 China

Melanin plays an important role in protecting organisms from ultraviolet radiation (UVR). Therefore, it is possible that differently colored strains can show different sensitivities to UVR. In the present work, life span, fertility and courtship behavior of wild type (w), ebony (e) and yellow (y) strains of Drosophila melanogaster were studied to evaluate their sensitivity to ultraviolet (UV). Because a range of photo- toxic effects of UVR are mediated through generation of free radicals, levels of free radicals, lipid per- oxide (malondialdehyde, MDA) and superoxide dismutase (SOD) activity of three strains were examined to indicate their antioxidant defending ability and oxidative status. It was shown that w always had the highest lifespan and fertility not only in the control but also in UV-exposed groups. Moreover, lifespan and fertility of e were significantly higher (P2. effect on the SOD activities. After pooling data from the control and UV-exposed groups, we found that w had a significantly (P0.05). MDA levels were increased in the UV dose-dependent manner (P=0.0495). In con- clusion, our results suggested that UVR can decrease life span and fertility of flies and do harm to courtship, which may be due to oxidative damage to flies tissues (e.g. central nervous system) induced by free radicals. w had the highest tolerance to UVR, which may be ascribed to its advantage of survival under the natural condition and at high level of SOD activity. Then differences of pigment between e and y in absorbing UV, shielding agai

关键词： ultraviolet radiation Drosophila melanogaste free radicals pigment

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Synthesis of todorokite by refluxing process and its primary characteristics

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Science china Earth Sciences 2004年第8期47卷 760-768页

作者： FENG Xionghan1, LIU Fan1, TAN Wenfeng1, LIU Xiangwen2.& HU Hongqing1 1. College of Resources and Environment, Huazhong agricultural university, Wuhan 430070,{2. 2. Testing center,{2. university of Geosciences, Wuhan 430074,{2. 1. College of Resources and Environment Huazhong Agricultural University 430070 Wuhan China 2. Testing center China University of Geosciences 430074 Wuhan China

Single phase and well-crystallined todorokite were synthesized by heating and refluxing process from birnessite as a precursor. The average chemical composition of the synthesized todorokites by refluxing for 8 h and for 2. h was Mg0.19MnO2.11(H2.)1.15 and in0.17-MnO2.10(H2.)0.88, respectively. The crystallinity of the todorokite increased and no other phase was produced with increasing refluxing period. The synthesized todorokites have the same morphologies and the similar structural characteristics with the natural todorokites and hydro-thermally synthesized samples. The chemical compositions of the synthetic tordorokites by refluxing process are close to those of todorokites synthesized by hydrothermal process, except a higher average oxidation state of Mn for the former.

关键词： todorokite,birnessite,manganese oxide,refluxing,hydrothermal,synthesis.

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Migration and population genetics of the grain aphid Macrosiphum miscanti (Takahashi) in relation to the geographic distance and gene flow

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Progress in Natural Science:Materials International 2005年第11期15卷 1000-1004页

作者： GUO Wei, SHEN Zuorui, LI Zhihong and GAO Lingwang (College of Agronomy and Biotechnology, china agricultural university, Beijing 100094,{2.) College of Agronomy and Biotechnology China Agricultural University Beijing 100094 China

The population genetics of the grain aphid Macrosiphum miscanti (Takahashi) is analyzed by microsatellite markers. Samples collected from 15 locations in china have been examined at 5 polymorphic microsatellite loci. Overall, genetic diversity displays a relation between the migration and gene flow in the grain aphid; a free and frequent gene flow is found in the eastern populations, and gene isolation occurs in the two western populations, especially Datong population and Guiyang population. The natural barriers may present an insurmountable obstacle preventing gene flow and aphid migration. However, a spatial genetic differentiation between populations is correlated with their geographical separation, indicating the geographic differentiation may play an important role in shaping the genetic structure of M. miscanti populations. In addition, most populations of grain aphids are out of Hardy-Weinberg equilibrium and there is het-erozygote deficit. Based on F statistics, the average genetic differentiation among different geographical populations is relatively low. It seems that the long distance migration of the grain aphid may enhance gene flow and decrease genetic differentiation among different populations .

关键词： Macrosiphum miscanti microsatellite gene flow migration.

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