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    01 October 2010, Volume 43 Issue 19
    CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    Genetic Improvement of Yield and Plant-Type Traits of Inbred Indica Rice Cultivars in South China
    LIU Chuan-guang,ZHANG Gui-quan,ZHOU Han-qin,FENG Dao-ji,ZHENG Hai-bo
    Scientia Agricultura Sinica. 2010, 43(19):  3901-3911 .  doi:10.3864/j.issn.0578-1752.2010.19.001
    Abstract ( 773 )   PDF (394KB) ( 677 )   Save
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    【Objective】 Cultivar yield improvement and plant-type traits development since the beginning of rice dwarfing breeding and their relationship were analyzed in order to search the strategies for continuously improving the yield potential of inbred indica rice in South China. 【Method】 Sixty-five leading cultivars released during 1957 to 2005, which were widely planted in South China, were used as experimental materials. Based on the field experiment under the same ecological and cultivation conditions, the evolution characteristics of yield and plant-type traits were analyzed, and correlation analysis and path analysis were used for detecting the relationship between yield improvement and plant-type traits development. 【Result】 Since the beginning of rice dwarfing breeding, the yield of inbred indica rice cultivars released in South China was improved continually, and it got to a summit in late 1980s, and then showed a downtrend until a new increasing trend began in 2000. Regression analysis result indicated that the plant height slowly increased during the course of cultivar evolution, but the extent was narrow. For leaf-morphologic traits, the length and width of top three leaves nearly had no change, but the angle and curvature of top three leaves decreased and had been improved significantly. Among the panicle-grain traits, the primary branch number, secondary branch number and number of spikelets per panicle increased gradually, but the panicle number per plant and seed setting rate declined and 1000-grain-weight decreased stepwise. The sink size per plant, biomass per plant and grain yield per plant increased significantly until the late 1980s,and then maintained on the plateau in the next tweenty years. 【Conclusion】 Yield level of inbred indica rice in South China has remarkably increased since the beginning of rice dwarfing breeding in 1950s, but stagnated in the past twenty years. The plant-type traits have been improved observably. It had been a main way of cultivar development that bred panicle-weight type cultivars for replacing gradually panicle-number type cultivars. In the next stage, the major approach of rice cultivar development in South China should be the increasing of sink size based on development of plant types.
    Mapping of MIPS1 and Development of CAPS Marker for Low Phytic Acid Mutation in Soybean
    YUAN Feng-jie,JIANG Ying,ZHU Shen-long,LI Bai-quan,FU Xu-jun,ZHU Dan-hua,DONG De-kun,SHU Qing-yao
    Scientia Agricultura Sinica. 2010, 43(19):  3912-3918 .  doi:10.3864/j.issn.0578-1752.2010.19.002
    Abstract ( 822 )   PDF (563KB) ( 642 )   Save
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    【Objective】 The objectives of the present study are to map the D-myo-inositol 3 phosphate synthase (MIPS EC 5.5.1.4) gene MIPS1 to enrich genetic information of this gene, and to develop molecular markers specific for the MIPS1 mutation for marker assisted selection of low phytic acid (LPA) trait of the mutant line Gm-lpa-TW-1. 【Method】 The candidate chromosome, in which MIPS1 is located, was identified by using soybean whole genome sequence and bioinformatics tools. The results were then verified through classical linkage analysis between microsatellites markers and the LPA trait using the F2:3 population derived from the cross between Gm-lpa-TW-1×Zhongdou 27. Cleaved amplified polymorphic sequences (CAPS) makers specific to the MIPS1 mutation of Gm-lpa-TW-1 were developed based on sequence information of all 4 MIPS genes; the usefulness of CAPS marker was verified using another segregating F2:3 population. 【Result】 Four MIPS genes were identified in soybean and MIPS1 was mapped on chromosome 18 (Linkage Group G) and proved to be the Glyma18g02210 gene. The DNA sequence of MPIS1 starts at 1 364 774 bp and is positioned on the upside of SSR markers Satt570(3 162 690 bp)and Satt115 (10 422 881 bp) at the genetic distance of 5.5 and 15.2 cM, respectively. A co-dominant CAPS marker, which completely segregates with the LPA trait, was developed and verified for the mutant MIPS1 gene of Gm-lpa-TW-1. 【Conclusion】 The present study mapped the MIPS1 on chromosome 18 for the first time, greatly enriched the genetic knowledge of this gene. The CAPS marker developed for the LPA trait of Gm-lpa-TW-1 can be used for marker assisted selection of this important trait and thus can enhance the efficiency of LPA soybean breeding.
    Genetic Variability and Evolutionary Peculiarity of Isoflavone Content and Its Components in Soybean Germplasm from China
    WANG Chun-e,ZHAO Tuan-jie,GAI Jun-yi
    Scientia Agricultura Sinica. 2010, 43(19):  3919-3929 .  doi:10.3864/j.issn.0578-1752.2010.19.003
    Abstract ( 958 )   PDF (366KB) ( 1113 )   Save
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    【Objective】 There are numbers of germplasm accessions of soybean, including both cultivated soybean (Glycine max (L.) Merr.) and wild soybean (Glycine soja Sieb. et Zucc.), available in China where the former were domesticated from the latter. It is a basic work to characterize the genetic variability and evolutionary peculiarity of the soybean germplasm in breeding for isoflavone contents. 【Method】 The 895 accessions, including 580 landraces, 106 released cultivars, 209 wild materials from various ecological regions in China with 88 released cultivars from abroad as reference, a total of 983 accessions were tested for their 12 isofavone contents by using rapid high performance liquid chromatography technique. 【Result】 A large variation in total isoflavone (TISF) and its components both in cultivated and wild soybeans in China was observed. The ranges of TISF in wild accessions, landraces and released cultivars were 927.29-7 932.94, 259.38-7 725.45 and 489.67-5 968.90 μg?g-1, with their averages of 2 994.51 μg?g-1, 3 241.33 μg?g-1, and 2 704.83 μg?g-1, respectively. In average, with the long term artificial selection, the total genistin group content (TG, especially 6’-O-malonylgenistin) and total glycitin group content (TGL, especially 6’-O-acetyl- and 6’-O- malonylglycitin) increased, while the total daidzin group content (TD, especially 6’-O-acetyldaidzin) decreased obviously, which led TISF in released cultivars lower than that in wild soybean. There existed also great variabibility of isoflavone contents in wild and cultivated soybeans within each eco-region as was that in the whole country. The TISF of cultivated soybeans was negatively correlated both with longitude (r =-0.264) and latitude (r=-0.380) at P<0.01 significance level, while no such correlation was found in wild soybeans, which indicated that the differential directions of artificial selection acted on the cultivated soybeans among geographic regions caused the correlation between genotypes and geographic sites in the cultivated soybean different from that of the wild soybeans. From the 983 accessions, elite ones, such as ZYD3621 (TISF 7 932.94 μg?g-1), N3188 (TISF 7 725.45 μg?g-1), N20793 (TGL 5 122.21 μg?g-1), etc. were screened out for isflavone breeding. 【Conclusion】 The evolutionary peculiarity of isoflavone content and its components from the wild species to cultivated landrace and to the released cultivars of soybean in China elucidated that the average of TISF, TG and TGL of G. max was higher than that of G. soja, while the average of TD of G. max was lower than that of G. soja. There existed great variation in total isoflavone and its components both in the whole country and in each eco-region in both wild and cultivated soybeans. Elite germplasm accessions with high isoflavone components in G. soja and G. max were screened out for breeding purposes.
    The Strategy for Maintaining Genetic Integrity of Soybean Germplasms ——Selecting Pure Lines Based on SSR Markers
    LI Ying-hui,CHANG Ru-zhen,QIU Li-juan
    Scientia Agricultura Sinica. 2010, 43(19):  3930-3936 .  doi:10.3864/j.issn.0578-1752.2010.19.004
    Abstract ( 815 )   PDF (349KB) ( 710 )   Save
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    【Objective】 The objective of the study is to identify the purity of soybean cultivars using SSR markers for efficiently keeping the genetic integrity of germplasm during germplasm conservation. 【Method】 The purity of 2 794 soybean cultivars or lines was analyzed by utilizing 59 SSR markers. 【Result】 90.1% of soybean accessions had high purity, which indicated that most of them could be easily used in the breeding and researches. 277 accessions with low purity were identified. Among them, 94.2% were landraces, accounting for 10.5% of total landraces (2 475). t test also showed that the homozygosity of landraces was significantly lower than that of cultivars or lines. 【Conclusion】 The population size should be kept larger during the propagation for those lower purity accessions compared to high purity accessions, otherwise the low frequent genotypes were easy to be lost. In order to lower the cost of propagation and convenient utilization, it is strongly recommended that pure lines should be selected for the low purity accessions based on the molecular markers, and some accessions from provinces, such as Hubei, Sichuan, Jiangsu, etc., should be put on the priority list.
    Differential Expression Analysis of Gibberellin-Induced Stem Elongation Genes in Sugarcane by cDNA-SRAP
    WU Jian-ming,LI Yang-rui,WANG Ai-qin,YANG Liu,YANG Li-tao
    Scientia Agricultura Sinica. 2010, 43(19):  3937-3944 .  doi:10.3864/j.issn.0578-1752.2010.19.005
    Abstract ( 764 )   PDF (696KB) ( 724 )   Save
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    【Objective】 The research was carried out to explore the molecular basis of the differential expression of GA-induced stem elongation genes of sugarcane and isolation of elongation-related genes. 【Method】 The plants were sprayed with gibberellin (GA3) at concentration of 200 mg?L-1 at early elongation stage, with water spraying as control. After extraction, equal quantity of the total RNAs of the same treatment was mixed to get two different mixed RNA pools for the GA3 treatment and the control. By cDNA-SRAP technique, different expressions of the genes were analyzed. 【Result】 Using 700 pairs of primers, about 15 000 cDNA fragments in size between 50-750 bp were amplified. Some fragments were different between the GA3 treatment and the control for different gene transcriptions in the young stem of sugarcane. Among them, 134 different cDNA fragments were selected. After reverse Northern blot analysis, 24 positive S-TDFs (cDNA-SRAP transcript derived fragments) were selected for cloning and sequencing analysis. After BLAST analysis, the 24 S-TDFs were divided into six categories according to gene function: energy and metabolism-related genes (4, accounting for 16.67%), genes of unknown functional proteins (6, accounting for 25%), unknown genes (10, accounting for 41.66%), cell wall biosynthesis and modification related genes (2, accounting for 8.33%), and transcription factor-related genes (1, accounting for 4.17%). 【Conclusion】 This study shows that the cDNA-SRAP technique is applicable to the analysis of gene differential expression. Some fragments of differentially expressed genes associated with sugarcane stem elongation were obtained, and may be used for investigating the molecular mechanism of sugarcane stem elongation.
    TILLAGE & CULTIVATION·PHYSIOLOGY & BIOCHEMISTRY·AGRICULTURE INFORMATION TECHNOLOGY
    Effects of Different Postures on Growth of Broadcasted Rice and the Regulating Factors of Physical Standing of Broadcasted Seedlings
    GUO Bao-wei,ZHANG Chun-hua,WEI Hai-yan,ZHANG Hong-cheng,CHEN Hou-cun,DAI Qi-gen,HUO Zhong-yang,XU Ke,XING Lin,GUAN Wen-wen,HUANG Xing-fu,YANG Xiong
    Scientia Agricultura Sinica. 2010, 43(19):  3945-3953 .  doi:10.3864/j.issn.0578-1752.2010.19.006
    Abstract ( 1035 )   PDF (270KB) ( 648 )   Save
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    【Objective】 To provide a theoretical basis for improving the population starting point quality of broadcasted rice, the effects of different postures on broadcasted rice and their regulating factors were studied in this experiment. 【Method】 The effects of different postures on broadcasted rice were studied by preparing the upright seedlings, the leaning seedlings and the laying seedlings and the regulating factors of physical standing of broadcasted seedlings under the conditions involving soil preparations, broadcasting height, water depth and different soil ball rates were investigated. 【Result】 Standing and establishment of the upright seedlings came earlier than the leaning seedlings and the laying seedlings, and the upright seedlings’ biomass , N accumulation, net assimilation rate, lodging resistance and harvest yield were higher than that of the and the seedlings laying seedlings. The rate of the upright seedlings was the highest under the conditions that the soil of top 5-6 cm was soft and the broadcasting height was 3 m, which was 81%. The rate of the upright seedlings decreased gradually as water depth increased. The plastic trays with bigger hole should be chosen moderately for raising seedling and the height of seedling should be controlled at 10-16 cm when broadcasting. 【Conclusion】 The upright seedlings’ growth status at different stages was better than the leaning seedlings and the laying seedlings, and significantly better than the laying seedlings. Increasing the rate of upright seedlings resulted in the high yield of broadcasted rice effectively. Under the conditions that the soil at the depth of top 5-6 cm was soft, the broadcasting seedlings were low and broadcasting height was from 3 to 4 m, it would have the best seedling standing.
    Effects of Tillage on Water Consumption Characteristics and Grain Yield of Wheat
    CHU Peng-fei,YU Zhen-wen,WANG Dong,ZHANG Yong-li
    Scientia Agricultura Sinica. 2010, 43(19):  3954-3964 .  doi:10.3864/j.issn.0578-1752.2010.19.007
    Abstract ( 980 )   PDF (381KB) ( 987 )   Save
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    【Objective】 The objective of this experiment was to study the effects of tillage on water consumption characteristics and grain yield of wheat under high-yield conditions by using the supplemental irrigation based on measured soil moisture, and to provide a scientific basis for water-saving and high-yield cultivation of wheat. 【Method】 This experiment was conducted under high-fertilized conditions during wheat growing seasons in 2007-2009 and water consumption amount, transpiration rate of flag leaf, leaf water use efficiency, grain yield and water use efficiency of wheat were analyzed by using five tillage styles which were strip rotary tillage (SR), strip rotary tillage after subsoiling (SRS), rotary tillage (R), rotary tillage after subsoiling (RS) and plowing tillage (P), respectively. 【Result】 The results showed that RS gained the highest total water consumption amount, followed by SRS and P which had no significant difference between them, while SR and R were lower than the above treatments. This indicated that total water consumption amount was significantly increased after subsoiling. The percentage of soil water consumption amount to total water consumption amount, the water consumption amount from anthesis to maturity stage and its water consumption percentage were the highest in SRS, and RS took second place, followed by P which was higher than SR and R. The above results indicated that SRS was beneficial for wheat to absorb soil water and improved the absorption of water during filling stage, which had favorable effect on grain filling. The percentage of irrigation amount to total water consumption amount of SRS and SR was lower than others, in which SR was the lowest, however, RS and P were the highest, which had no significant difference between them, and R took second place. The leaf water use efficiency at middle and later filling stages of SRS and RS, which had no significant difference between them, were significantly higher than other treatments. SR and R had lower leaf water use efficiency than P. This illustrated that subsoiling had favorable impact on keeping high photosynthetic ability during middle and later filling stages. SRS and RS had the highest grain yield which had no significant difference between them, and P took second place, followed by SR and R. This illustrated that subsoiling was beneficial to improving the grain yield of wheat. SRS had the highest water use efficiency and irrigation benefit, and RS took second place. SR and R had lower water use efficiency and irrigation benefit than P. This illustrated that SRS had favorable effect on improving water use efficiency. 【Conclusion】 As far as high-yield and water-saving were concerned in the experiment, the most appropriate treatment for recommendation was the strip rotary tillage after subsoiling.
    Relationship Between Dry Matter Accumulation and Sucrose Metabolism During Pod Development in Peanut (Arachis hypogaea L.)
    CUI Guang-jun,LIU Feng-zhen,WAN Yong-shan
    Scientia Agricultura Sinica. 2010, 43(19):  3965-3973 .  doi:10.3864/j.issn.0578-1752.2010.19.008
    Abstract ( 796 )   PDF (258KB) ( 714 )   Save
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    【Objective】 The experiment aimed at study on the relationship between peanut pod dry matter accumulation and sucrose metabolism. 【Method】 With the seeds of normal peanut line 05D610 and its wrinkled mutant line 05D677 as material, the dynamic changes of pod dry weight (during 6-72 d after peg penetration), contents of soluble sugar, sucrose,fructose,glucose,starch, protein, and oil in seeds (during 6-72 d after peg penetration), and activities of sucrose-metabolizing enzymes (during 30-72 d after peg penetration) were examined. 【Result】 The period of 24-54 d after peg penetration was a rapid dry weight accumulation phase which determined the final dry weight, and pod dry weight accumulation rate of 05D610 was 2.4 times that of 05D677 in the same period. At harvest, dry weight of 05D610 and 05D677 were 2.06 g and 1.28 g, respectively, the difference between them was highly significant. In the period of 30-72 d after peg penetration, hexose/sucrose ratio and oil content of 05D610 seeds were always significantly higher than that of 05D677, while the protein content of 05D610 being always significantly lower than that of 05D677, and the starch content in seeds was not different significantly between 05D610 and 05D677. During the period of seed dry matter accumulation, the activity of sucrose synthase (SS) was significantly higher than that of sucrose phosphate synthase (SPS), which was the main enzyme on sucrose syntheses. SS activity was higher than acid invertase (AI) and neutral invertase (NI), which was also the main enzyme for direction of sucrose cleavage. In conclusion, SS is the main enzyme for sucrose metabolism at the stored matter accumulation stage of peanut seeds. SS (synthesis) activity in seeds showed slight difference between 05D610 and 05D677.SS (cleavage) activity of 05D610 was significantly lower than that of 05D677. SPS activity of 05D610 was significantly higher than that of 05D677. 【Conclusion】 The phase 24-54 d after peg penetration is more important for pod dry weight accumulation. SS (cleavage) is a key enzyme for organic matter accumulation. The difference in hexose/sucrose ratio, SPS activity, SS (cleavage) activity between 05D610 and 05D677 may be the dominant factor leading to their difference in dry weight accumulation rate of pod, pod dry weight and content of components in peanut seeds.

    PLANT PROTECTION
    Effects of Grafting Cotton on Verticillium Wilt Resistance,Yield and Fiber Quality of Cotton
    HAO Jun-jie,MA Qi-xiang,LIU Huan-min,JIA Xin-he,DONG Zhong-dong,LIU Shu-mei,CUI Xiao-wei,ZHANG Zhi-xin
    Scientia Agricultura Sinica. 2010, 43(19):  3974-3980 .  doi:10.3864/j.issn.0578-1752.2010.19.009
    Abstract ( 868 )   PDF (230KB) ( 844 )   Save
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    【Objective】 This study aimed at investigating the effects of grafting cotton on Verticillium wilt resistance, yield and fiber quality of cotton, and farther discussing the feasibility of controlling cotton Verticillium wilt using grafting. 【Method】 Two sea island cotton (Gossypium barbadense L.) lines (resistant to Verticillium dahliae), Hai 7124 and Pima 90, were selected as rootstocks. The scions were two upland cotton (G. hirsutum) cultivars Xiangzamian 21 (tolerant to Verticillium dahliae) and Jimian 11 (susceptible to Verticillium dahliae). The four grafting combinations were completed and planted in the naturally infected cotton field, and the data of cotton Verticillium wilt, yield and fiber quality were investigated in grafting and non-grafting cotton types.【Result】 Compared to the scion controls, the severity of cotton Verticillium wilt on the grafting cotton was significantly reduced, and the resistance to cotton Verticillium wilt of some grafting combinations was not significantly different from the resistant rootstock controls. The plant height, number of sympodial branches/plant, number of total bolls/m2, seed cotton yield and lint yield of grafting cotton were higher than that of the scion controls, respectively. Grafting nearly had no effects on growth, lint, boll weight and fiber quality of the majority of grafting combinations. 【Conclusion】 This study showed that grafting could be used as an effective method for control cotton Verticillium wilt and increase yield in continuous cropping cotton field.

    Prokaryotic Expression of Fdn-I , Preparation of Rabbit Anti-Fdn-I Antibody and Analysis of the Fdn-I Levels in ToMV-Infected Tobacco Leaves
    SUN Xian-chao,LI Yong,ZHOU Chang-yong,QING Ling
    Scientia Agricultura Sinica. 2010, 43(19):  3981-3987 .  doi:10.3864/j.issn.0578-1752.2010.19.010
    Abstract ( 754 )   PDF (565KB) ( 514 )   Save
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    【Objective】 The objective of the study is to construct the prokaryotic expression vector of Fdn-I and express the soluble Fdn-I in E. coil BL21 for preparation of rabbit anti-Fdn-I antibody for the analysis of expression of Fdn-I in tobacco leaves infected by ToMV. 【Method】 Fdn-I was amplified from the full-length cDNA of Fdn-I by PCR and cloned into pEGX-6p-1, an expression vector fused with GST, to construct the pEGX-Fdn-I. The recombinant plasmid was transformed into E. coil BL21 to express the soluble GST-Fdn-I protein in the optimized condition. GST-Fdn-I protein was purified with high-affinity GST resin to immunize rabbit for preparing anti-Fdn-I antibody. The title was determined by enzyme-linked immunosorbant assay (ELISA). The specificity of anti-Fdn-I antibody and the expression of Fdn-I in tobacco leaves infected by ToMV were detected by Western blot method. 【Result】 The soluble GST-Fdn-I protein with molecular weight 41.3 kD was successfully expressed in E. coil BL21 induced with 0.3 mmol?L-1 IPTG at 28℃. About 4 mg fusion protein was purified and used to immunized rabbit. Anti-Fdn-I antibody with the title of 1/6 400 was obtained. Western blotting analysis showed that it could bind with Fdn-I specially expressed in E. coil and Yeast. In ToMV infected tobacco leaves, the expression of Fdn-I was lower than that in health tobacco leaves. 【Conclusion】 The recombinant GST-Fdn-I protein in E. coli and its polyclonal antibody with high title and specificity were successfully achieved. The result of Western blot with the polyclonal antibody showed that the expression of Fdn-I in tobacco leaves was decreased by the infection of ToMV.

    SOIL & FERTILIZER·WATER-SAVING IRRIGATION·AGROECOLOGY & ENVIRONMENT
    Effects of Tillage Systems on Fields in Chengdu Plain I. The Effects of Tillage Systems on Soil Properties and Crop Yields
    LIANG Shu-min,XIE Rui-zhi,TANG Yong-lu,YANG Jin-zhong,LI Chao-su,WANG Ling-bian,WU Chun,LI Shao-kun
    Scientia Agricultura Sinica. 2010, 43(19):  3988-3996 .  doi:10.3864/j.issn.0578-1752.2010.19.011
    Abstract ( 753 )   PDF (305KB) ( 819 )   Save
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    【Objective】 In order to provide a theoretical basis for the main tillage systems and control technology of Chengdu plain, the effects of different tillages on soil properties and yield were compared. 【Method】 Based on long-term experiments, 5 years of field trials were carried and the tillages on crop yield and soil properties and their relationship were analysed. The five treatments were wheat and rice conventional tillage (WRCT); wheat no-tillage and rice conventional tillage (WNRCT); wheat and rice no-tillage (WRNT); wheat and rice ridge tillage (WRRT); wheat no-tillage and rice conventional tillage and autumn vegetable no-tillage (WNRCVNT).【Result】 The effects of different tillage systems on soil properties were different: Compared with the control, single and double no-tillage all reduced soil bulk density of the 0-10 cm layer, increased that of the 10-20 cm layer; which increased the small soil porosity, and increased the big soil porosity of the 0-10 cm layer, while increased the proportion of small pores, decreased the big soil porosity of the 10-20 cm layer, which improved the soil pore size distribution. It was not significantly different in soil specific gravity and soil hygroscopic water between tillage treatments. No-tillage decreased the soil specific gravity. The seepage rate of soil was increased too, which was not good for rice growth. No-tillage increased the soil organic. No-tillage straw mulching reduced alkalescence of the 0-10 cm soil layer, but increased alkalescence of the 10-20 cm soil layer. The average yield of five years showed that no-tillage increased wheat production, but significantly reduced rice production. 【Conclusion】 No-tillage resulted in the formation of “loose above and compact below” soil structure, which changed the soil permeability. Especially in the 10-20 cm, it broke the traditional plowpan. But no-tillage changed the soil structure which the effects on wheat and rice yield is not consistent. Under the same conditions, no-tillage is beneficial to increase wheat yield, but it is negative to rice growth and yield. The reason mainly due to no-tillage increased the rates of soil water seepage, and it caused leakage of water and nutrients seriously.

    Study on Fertilization Effect and Fertilizer Contribution Rate of Different Crops at Present Production Conditions
    WANG Wei-ni,LU Jian-wei,LI Yin-shui,ZOU Juan,SU Wei,LI Xiao-kun,LI Yun-chun
    Scientia Agricultura Sinica. 2010, 43(19):  3997-4007 .  doi:10.3864/j.issn.0578-1752.2010.19.012
    Abstract ( 1010 )   PDF (342KB) ( 832 )   Save
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    【Objective】 The purpose of the research was to study the effect of fertilization on rice, wheat, rapeseed and cotton yields, and to investigate the fertilizer contribution rate (FCR) and agronomic efficiency (AE) in different crops at present conditions.【Method】 Field experiments of rice, wheat, rapeseed and cotton were, respectively, conducted at 251, 47, 62 and 26 sites in 21 counties of Hubei Province during 2006-2008. 【Result】 The results indicated that combined application of N, P and K(NPK) increased the yields of four crops significantly. The average yields of NPK treatment of rice, wheat, rapeseed and cotton were 7 697, 4 520, 2 597 and 4 220 kg?hm-2, which were 46.7%, 109.8%, 173.7%, and 68.6% higher than those of CK treatment, respectively. The FCR to rice, wheat, rapeseed and cotton yields were 29.6%, 48.6%, 56.2% and 38.0%, corresponding to 7.2, 7.7, 4.0 and 3.0 kg?kg-1 of AE, respectively. 【Conclusion】 The combination of N, P and K fertilizers significantly increased crop yields, and the responses of different crops to fertilizer were different. In addition, compared with the past, chemical fertilizer plays much more important role in agricultural production at present.

    Response of Olsen-P to P Balance in Black Loessial Soil Under Long-Term Fertilization
    PEI Rui-na,YANG Sheng-mao,XU Ming-gang,FAN Ting-lu,ZHANG Hui-min
    Scientia Agricultura Sinica. 2010, 43(19):  4008-4015 .  doi:10.3864/j.issn.0578-1752.2010.19.013
    Abstract ( 806 )   PDF (326KB) ( 723 )   Save
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    【Objective】 Response of Olsen-P to P balance in a black loessial soil was studied in a long-term fertilization experiment carried out in Pingliang, Gansu province for the purpose of providing a theoretical basis for the scientific application of phosphate fertilizer in the Loess Plateau dryland farming areas. 【Method】 The relationships between Olsen-P change and the budget of soil P balance in the treatments of CK, N, NP, M, NPM were studied by the method of linear regression based on a 28-year (1979-2007) experiment. 【Result】 The results showed that long-term application of M, NP, and NPM resulted in significant increase of Olsen-P by 0.54, 0.64 and 1.11 mg?kg-1?a-1, respectively. While the soil Olsen-P content remained stable or showed a decreasing trend in the CK and N treatments. The increase amount of Olsen-P changed with P balance. Application of NP, M, NMP increased the amount of Olsen-P significantly. The P balance was very significantly (P<0.01) correlated with the Olsen-P. With an average surplus of 100 kg phosphorus per hm2, the soil Olsen-P increased by 3.85, 0.29 and 0.53 mg?kg-1, in the NP, M, and NPM treatments, respectively. Application of chemical fertilizer increased Olsen-P was 11.6 times higher than that of manure, followed by the chemical fertilizer combined with manure. 【Conclusion】 Changes of soil Olsen-P followed soil phosphorus surplus and the close correlation between the increased amount of Olsen-P and the form applied phosphorus were observed. Long-term application of chemical P fertilizer resulted in the increase of the amount of Olsen-P is higher than manure obviously in black loessial soil.

    Quantification of Transpiration and Evaporation over Agricultural Field Using the FAO-56 Dual Crop Coefficient Approach —A Case Study of the Maize Field in an Oasis in the Middlestream of the Heihe River Basin in Northwest China
    ZHAO Li-wen,JI Xi-bin
    Scientia Agricultura Sinica. 2010, 43(19):  4016-4026 .  doi:10.3864/j.issn.0578-1752.2010.19.014
    Abstract ( 1071 )   PDF (579KB) ( 1287 )   Save
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    【Objective】 The quantification of transpiration and evaporation in an oasis field in the middlestream of the Heihe River basin in Northwest China was studied in order to provide a basis for laying down a reasonable crop irrigation system and improving the utilization efficiency of regional water resources. 【Method】 Based on the microclimatic and other supplementary experimentation data of maize field in Linze Inland River Basin Research Station, China Ecosystem Research Network, four different Penman-Monteith equations with two time-steps suggested by FAO-56 and ASCE were applied to calculate reference evapotranspiration (ET0) over a maize field in 2009, then FAO-56 dual crop coefficient method was applied to calculate canopy transpiration and soil evaporation over the same field in 2009. 【Result】 The actual evapotranspiration (ETc) for the FAO-56-PM 24h, ASCE-PM 24h, FAO-56-PM 1h, ASCE-PM 1h with dual crop coefficient methods totaled 672.1 mm, 766.2 mm, 991.2 mm and 805.6 mm, respectively. 【Conclusion】 Compared with the eddy covariance data and measured evaporation data by micro-lysimeter, the FAO-56-PM 24h equation can well estimate ET0, and can provide a fairly good estimation of ETc with dual crop coefficient. The total evapotranspiration of the maize field in 2009 was 671.2 mm, with the mean daily value of 4.1 mm. The cumulative amount of transpiration and evaporation were 498.5mm and 172.7 mm, accounting for 74.2% and 25.8% of the total evapotranspiration during the maize growing season, respectively.

    HORTICULTURE
    Changes of the Photosynthetic Pigment and Differential Expression of the Correlated Genes in a Chlorophyll-Deficient Cucumber Mutant (Cucumis sativus L.)
    MIAO Han,GU Xing-fang,ZHANG Sheng-ping,WANG Xiao-wu,FANG Zhi-yuan,ZHANG Zhen-xian
    Scientia Agricultura Sinica. 2010, 43(19):  4027-4035 .  doi:10.3864/j.issn.0578-1752.2010.19.015
    Abstract ( 736 )   PDF (438KB) ( 1439 )   Save
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    【Objective】 Cucumber chlorophyll-deficient mutant is an ideal material for studies on the photosynthetic system and genetic breeding. To make clear on the mechanism of the leaf colour transformation in yellow leaf mutant will provide a theoretical basis for quantitative trait loci gene mapping and gene cloning. 【Method】 A cucumber chlorophyll-deficient mutant named 9110Gt and its wild type named 9110G were used as materials in this study. The photosynthetic pigment components, contents and Pchl contents in 9110Gt and 9110G were analysed. cDNA-AFLP and cDNA-Ad-SRAP were employed to detect the differentially expressed genes. 【Result】 Spectral analysis showed that there was no significant difference in the pigment components between 9110Gt and 9110G, but the contents of photosynthetic pigment and protochlorophyll in 9110Gt were lower than in wild type in yellow period. Nine candidate transcript derived fragments (TDFs) were obtained. The candidate transcript derived fragments had highly identities with cucumber mitochondrial and chloroplast genome sequence. 【Conclusion】 It was concluded that there was a blockage in the protochlorophyllide biosynthesis, then leading to lower chlorophyll content and make changes in the proportion of photosynthetic pigment of mutant. The leaf colour mutant was may be due to gene mutations in chloroplast development and chlorophyll biosynthesis.

    Relationship Between Carotenoid Content and Low-Light-Tolerance or Chilling- and Low-Light-Tolerance of Pepper Varieties
    XIE Jian-ming,YU Ji-hua,HUANG Gao-bao,FENG Zhi
    Scientia Agricultura Sinica. 2010, 43(19):  4036-4044 .  doi:10.3864/j.issn.0578-1752.2010.19.016
    Abstract ( 929 )   PDF (286KB) ( 584 )   Save
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    【Objective】 Several correlations between the changes of carotenoid content and the tolerance of pepper seedlings under low light or low light with low temperature stress were studied. The objective of this study is to screen suitable indexes for evaluating low light- tolerance or chilling- and low light-tolerance of pepper seedlings.【Method】The correlations between the carotenoid content at different times and the tolerance of 12 pepper varieties (expressed as the averaged subordinate function values) under low light or low light with low temperature stress were studied by using correlation analysis. 【Result】 The carotenoid contents in pepper leaves decreased both under 28℃/18℃, 100 μmol?m-2?s-1 PFD stress and under 15℃/5℃, 100 μmol?m-2?s-1 PFD stress, and the carotenoid contents were more smaller in pepper leaves treated under low light with low temperature stress than in those treated under only low light stress. There were strong positive correlations between the averaged subordinate function values and the carotenoid contents in pepper leaves treated under 28℃/18℃, 100 μmol?m-2?s-1 PFD stress for 5, 10, 15, and 20 days. Significant negative correlations existed between the averaged subordinate function values and the carotenoid contents in pepper leaves treated under 15℃/5℃, 100 μmol?m-2?s-1 PFD stress for 10, 15, and 20 days. 【Conclusion】 It was suggested that carotenoid content in pepper leaves treated under 28℃/18℃, 100 μmol?m-2?s-1 PFD stress for 5, 10, 15, and 20 days or 15℃/5℃, 100 μmol?m-2?s-1 PFD stress for 10, 15, and 20 days could be used as good indicators for identification and screening low light- tolerant or chilling- and low light- tolerant pepper varieties. The higher the carotenoid content, the higher tolerance to low light stress. On the contrary, the higher the carotenoid content, the lower tolerance to low light with low temperature stress.

    Effects of Vineyard Cover Crops on Main Nitrogen Compounds in Grape Berry and Wine from Vitis viniferal L. cv. Cabernet Sauvignon
    XI Zhu-mei,ZHANG Zhen-wen,MA Xin-li,MA Shao-qing,LI Hua
    Scientia Agricultura Sinica. 2010, 43(19):  4045-4052 .  doi:10.3864/j.issn.0578-1752.2010.19.017
    Abstract ( 781 )   PDF (297KB) ( 604 )   Save
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    【Objective】 This study was conducted to determine the effect of inter-row cover crops in vineyard on main nitrogen compounds in grape berry (skin, pulp and seed) and wine from Cabernet Sauvignon. 【Method】 Compared with soil tillage (control), three cover crops, white clover, alfalfa and tall fescue were sown in vineyard. The main nitrogen compounds (total nitrogen, soluble protein and free amino acid) of mature grape berry (skin, pulp and seed) and wines vinified under the same conditions were extracted and analyzed with micro-kjeldahl method and full- automatic biochemical analyzer. 【Result】 The protein content in seed of alfalfa treatment was higher significantly than that of the soil tillage, and the total N and protein contents in skins, pulps and seeds decreased by different cover crops treatments. The total N content in seeds was the highest, which was 41.6% of the total N content in the whole berries, total N in pulps and skins accounted for 33.9% and 24.50% of the whole berries, respectively. While 46.0% of total nitrogen compounds in berries were proteins, the protein contents in seeds, pulps and skins were 50.9%, 33.9% and 15.2% of the total proteins, respectively. No significant difference was noticed among different treatments in total N content and protein content in wines. Compared to soil tillage, the alfalfa and tall fescue sward treatments increased the total amino acid contents of grape berry but the white clover treatment decreased them, and there was no significant difference between cover crop treatments and the control. Proline was the most abundant amino acid in grape berry in four treatments, which accounted for 45.9% to 56.9% of the total amino content, next in abundance was arginine and lysine, which accounted for 16.4% to 24.2% of the total amino acid content. The sward treatments showed a higher content of amino acid contents in wines, and there were significant differences (P<0.05) between two cover crop treatments (tall fescue, alfalfa) and soil tillage. Praline was also the most abundant amino acid in wine, which accounted for 90.11% to 92.45% of the total amino acid content. 【Conclusion】 Cover crops in vineyard increased total free amino acid content of grape and wine, although decreased total N and protein content of grape berry. The conclusion is that the cover crops may improve the quality of wine.

    Analysis of Differential Protein Expression of Tea Callus with Different Catechins Contents
    ZHANG Li-ming,WANG Yun-sheng,GAO Li-ping,XIA Tao
    Scientia Agricultura Sinica. 2010, 43(19):  4053-4062 .  doi:10.3864/j.issn.0578-1752.2010.19.018
    Abstract ( 1007 )   PDF (916KB) ( 796 )   Save
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    【Objective】 To establish a two-dimensional electrophoresis (2-DE) of proteome suitable for tea callus and analyze the differential protein expression patterns of tea callus with different catechins contents, which could provide a basis for the further study of proteomics of the catechins biosynthesis. 【Method】 Using the improved protein extraction, 2-DE and LTQ-ESI-MS/MS method, the differential protein expression profiling was investigated using the tea callus of “Yunjing63X” (with low catechins contents), “Yunjing63Y” (with higher contents), and “Yunjing63Y” cultured under light (with the highest contents). 【Result】 Protein quantitative and SDS-PAGE electrophoresis results showed that TCA-acetone method was the best for extracting tea callus proteins. And 14 differential protein spots were identified by 2-DE electrophoresis, LTQ-ESI-MS/MS and database searching. The glutathione S-transferase, WD40 family protein, catechol O-methyltransferase, S-adenosylmethionine synthetase, pectin methylesterase and so on were identified among those differential protein spots. 【Conclusion】 The predicted function of these picked proteins were involved in many physiological reactions, such as phenylpropanoid and flavonoids biosynthesis, transport and regulation, ethylene biosynthesis, cell wall metabolism , glycolysis pathway, and signal transduction.

    Salt Tolerance Screening of 32 Taxa from Chrysanthemum and Its Relative Genera

    GUAN Zhi-yong,CHEN Su-mei,CHEN Fa-di,YIN Dong-mei,LIU Zhao-lei,TANG Juan,YANG Fan
    Scientia Agricultura Sinica. 2010, 43(19):  4063-4071 .  doi:10.3864/j.issn.0578-1752.2010.19.019
    Abstract ( 846 )   PDF (339KB) ( 819 )   Save
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    【Objective】 In order to establish a method for salt tolerance screening of Chrysanthemum as well as to discover salt tolerant germplasms for chrysanthemum breeding, salt tolerance of 30 species from Chrysanthemum and its relative genera was identified in comparison with two chrysanthemum cultivars. 【Method】 Four species from Chrysanthemum and its relative genera were hydroponically cultured in Hoagland solution supplemented with NaCl at different concentrations of 0, 40, 80,120, 160 and 200 mmol?L-1, respectively. The proper screening concentration of NaCl was determined using the ratio of injured leaf area per plant. The regression equation models regarding the correlation between the stressed duration and the ratio of injured leaf area per plant were established, from which the time when the ratio of injured leaf area per plant reached 50% of the whole plant was figured out. The salt tolerance of 32 taxa was sequenced based on the time. This sequence was compared with those judged from other leaf morphological indexes. A comprehensive evaluation of salt tolerance of 32 taxa was made by using hierarchical clustering analysis.【Result】The proper NaCl concentration for screening salt-tolerance was 120 mmol?L-1. Variation coefficients of different indexes under the NaCl concentration were great, and correlation coefficient between sequences of salt tolerance based on different indexes was high. Three types of equations including 32 regression equations were established, and the regression equations all demonstrated good regression effects. 【Conclusion】 Salt tolerance screening of plants from Chrysanthemum and its relative genera can be achieved effectively and rapidly by leaf morphological indexes. Clustering analysis showed that 32 taxa could be divided into extremely salt tolerant, salt tolerant, moderately salt tolerant and salt sensitive grade, respectively. Artemisia japonica, Aster spathulifolius, Crossostephium chinense are extremely salt tolerant, Tanacetum vulgare and Chrysanthemum crassum are salt-tolerant, seven taxa represented by Artemisia vulgaris, Leucanthemum vulgare are moderately salt tolerant, 14 taxa represented by Chrysanthemum zawadskii, Ch. chanetii, Ch.vestitum, Ch. lavandulifolium are salt sensitive ones.

    STORAGE·FRESH-KEEPING·PROCESSING
    Research of Anthocyanin Composition in Blue and Purple Wheat Grains
    ZHAO Shan-cang,LIU Bin,ZHAO Ling-jun,GUO Dong-liang,MAO Jiang-sheng,GUO Chang-ying,REN Feng-shan,WANG Xian-ze,TIAN Ji-chun
    Scientia Agricultura Sinica. 2010, 43(19):  4072-4080 .  doi:10.3864/j.issn.0578-1752.2010.19.020
    Abstract ( 906 )   PDF (464KB) ( 1131 )   Save
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    【Objective】 A systematic method for anthocyanin identification using tandem mass spectrometry (MS/MS) coupled to Ultra performance liquid chromatography (UPLC) with photo-diode array detection (PDA) was developed. Isolation and identification of anthocyanins from blue, purple wheat grains were made, and then the compositions of anthocyanin were revealed. 【Method】 Wheat grains were extracted by 90% methanol-water solution (containing 0.5% formic acid), ultrasonic assisted extraction was employed, and purified on SPE C18 column. The precursor ions of anthocyanins were scanned using UPLC/MS/MS on a triple quadrupole instrument allowing for the specific determination of each category of anthocyanins. Further characterization of each anthocyanin was performed using MS/MS product-ion scanning, full scanning and MRM (multiple reaction monitoring). 【Result】 Fourteen anthocyanins were identified in blue and purple wheat grains. Significant difference was found in the composition and content of anthocyanins among different wheat varieties. 【Conclusion】 The study has defined the compositions and contents of anthocyanins in blue and purple wheat grains. The present approach allows mass spectrometry to be used as a highly selective detector for rapid identification and characterization of anthocyanins in wheat grain.

    Study on the Composition and the Structure of Polysaccharide of Almond Gum

    WANG Li-xin,WANG Sen,GAO Ai-ling
    Scientia Agricultura Sinica. 2010, 43(19):  4081-4087 .  doi:10.3864/j.issn.0578-1752.2010.19.021
    Abstract ( 913 )   PDF (307KB) ( 669 )   Save
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    【Objective】 To predict the constitutes of amino acid and monosaccharide, and the structure of polysaccharide of almond gum. 【Method】 The compositions of amino acid and monosaccharide were determined by ion chromatography and the polysaccharide structure was analyzed by using chromatographic infrared analyzer. 【Result】 Almond gum consisted of 12 kinds of amino acids, Thr, Gly, Ala, His, Arg, Phe, Ser, Glu, Asp, Pro, Val, and Tyr, with Thr being the highest content (47.89%). The monosaccharide of almond gum contained Glua, xylose, galactose, arabinose, and little rhamnose and fucose and their molar ratios of monosaccharide were 24.35﹕9.25﹕33.75﹕31.60﹕0.74﹕0.31. The main chain of polysaccharide of almond gum could contain 1, 6-linked Galp and 1,4-linked Araf. Non-reducing end group was 1-linked Fucp, 1-linked Ribf, or 1-linked GluA. The branching point was mainly located in 1,2,6-linked Galp. 【Conclusion】 This research will play an important role in the further development and utilization of almond gum.

    ANIMAL SCIENCE·RESOURCE INSECT
    Comparison of Nitrate Reduction, Methane Production and Fermentation Characteristics Among Ruminal Microbial Fractions
    LIN Miao,GUO Wang-shan,REN Li-ping,ZHOU Zhen-ming,MENG Qing-xiang
    Scientia Agricultura Sinica. 2010, 43(19):  4088-4093 .  doi:10.3864/j.issn.0578-1752.2010.19.022
    Abstract ( 908 )   PDF (250KB) ( 586 )   Save
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    【Objective】 An in vitro study was conducted to evaluate the ability of nitrate reduction and its effect on ruminal methano genesis and fermentation characteristics of various microbial fractions. 【Method】 Using the Menke’s gas production method in vitro, pure substrates formulated with soluble starch, Avicel, and sodium nitrate were anaerobicly incubated for 24 hours. Physical centrifugation and chemicals selections were used to differentiate microbial fractions as follows: whole rumen fluid (WRF), protozoa (P), bacteria (B), fungi (F), protozoa plus bacteria (P+B), protozoa plus fungi (P+F), bacteria plus fungi (B+F), and negative control (CTN). 【Result】 The results showed that the degradation of nitrate by fraction P was higher than fraction B (P<0.001), while fraction F had little contribution to nitrate reduction, even for its co-culture with fractions of P or B. The gas production and nitrate reduction were greatest in WRF, followed by fractions of P+B and P, and the three fractions had greater values in methane (CH4) proportion, total VFA (TVFA) concentration and acetate molar proportion (P<0.001). Nitrate-N addition increased rumen microbial protein synthesis with the greatest synthesis occurring in P+B fraction. 【Conclusion】 Both ruminal fractions of P and B had the ability to reduce nitrate (NO3-) and nitrite (NO2-) with a greater ability in P fraction. F fraction had minor ability of nitrate reduction in this substrate. Ruminal protozoa and bacteria represented predominant populations responsible for nitrate reduction, methanogenesis, and microbial protein synthesis.

    Effect of Different Contents of Plant Protein on the Incidence of Diarrhea and Blood Parameters in Calves Aged 6-11 Days
    ZHANG Nai-feng,DIAO Qi-yu,LI Hui
    Scientia Agricultura Sinica. 2010, 43(19):  4094-4100 .  doi:10.3864/j.issn.0578-1752.2010.19.023
    Abstract ( 967 )   PDF (327KB) ( 555 )   Save
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    【Objective】 This study was designed to determine the influence of plant protein contents of milk replacers on the incidence of diarrhea and blood parameters in the calf aged 6-11 days. 【Method】 Twelve male Chinese Holstein calves were randomly assigned to three milk replacers containing 20%, 50% or 80% plant protein of total protein. 【Result】 Compared with the other milk replacers, the milk replacer containing 80% of plant protein of total protein significantly decreased the serum IgG concentration in 7-day-old calves, but significantly increased the serum alkaline phosphatase (AKP) concentration in 9-day-old calves, and significantly elevated the incidence rate of diarrhea in the first 2 or 3 days of experimental period. However, the serum concentration of total protein (TP), urea nitrogen (BUN), cortisol (Cort) and growth hormone (GH) was not different significantly among the treatments. 【Conclusion】 The plant protein content in milk replacers affected the health and blood parameters of 6- to 11-day-old calves, and an appropriate plant protein content below 50% of total milk replacer protein was suggested for the health and the smooth transition from milk to milk replacers of calves.

    Study on Nonlinear Mixed Effect Model for Evaluation of Muscovy Body Weight for Growth
    ZHANG Yuan-yue,LIU Xiao-chun
    Scientia Agricultura Sinica. 2010, 43(19):  4101-4108 .  doi:10.3864/j.issn.0578-1752.2010.19.024
    Abstract ( 754 )   PDF (332KB) ( 704 )   Save
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    【Objective】 The aim of the study is to describe and estimate the trajectory and parameters of body weight growth of native Muscovy. 【Method】 One hundred and sixteen Muscovy ducks were fed and observed for 21 weeks, five body weight growth functions including Gompertz, Logistic, Von Bertalanffy, Richards, and Brody were estimated, nonlinear mixed effect models were fitted to data of body weight in Muscovy, and the 8 growth parameters including mature weight, Point of inflection (POI), POI weight, birth weight, absolute growth rate, relative growth rate, absolute maturing rate, and relative maturing rate were computed for these models in this study. The results of fitting and estimating with these different growth models were compared using information criteria,error variance, and accuracy of estimated growth parameters for evaluating the alternative models. 【Result】 The 5 nonlinear mixed effect models with 8 growth parameters each were fit for body weight of Muscovy ducks. Their accuracies had a much larger increase than these of the nonlinear fixed effect models. Among the 5 nonlinear mixed effect models for the body growth of female and male Muscovy, information criteria of Gompertz growth model were least, and reduction of residual error variance of this model was up to 99.92%. For the body growth of male or female Muscovy, information criteria of Richards growth model was least among the 5 nonlinear mixed effect models. Reduction of residual error variance of this model was up to 89.80% for male group, 91.81% for female group. 【Conclusion】 Gompertz,Richards nonlinear mixed effect models are best growth models for fitting the body growth of Muscovy,for male or female Muscovy, respectively.

    VETERINARY SCIENCE
    Prevalence of Serotypes and Virulence Genes and Antimicrobial Susceptibility of Pathogenic Escherichia coli Isolates from Swine
    WANG Xiu-mei,JIANG Hong-xia,LIAO Xiao-ping,ZHANG Wan-jiang,ZHU Heng-qian,ZHANG Yue,LIU Ya-hong
    Scientia Agricultura Sinica. 2010, 43(19):  4109-4115 .  doi:10.3864/j.issn.0578-1752.2010.19.025
    Abstract ( 908 )   PDF (332KB) ( 880 )   Save
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    【Objective】 The aim of the study was to investigate the prevalence of serotypes, virulence genes and resistance phenotypes of Escherichia coli isolates from swine. 【Method】 O serogroups were identified by agglutination with specific antisera. Resistance phenotypes were tested by the broth microdilution. All strains were screened for virulence genes by PCR. 【Result】 The finding showed that more than 50% of E. coli isolates possessed astA, Stx2e and eaeA genes, while the combinations of Stx2e+astA and Stx2e+eaeA were more prevalent. Fifteen O serogroups were identified for 53 E. coli isolates, of which O8 and O64 were dominant serogroups. All strains of O8 serogroup carried astA gene, most of the O8 strains were resistant to tetracycline, ciprofloxacin, enrofloxacin and chloramphenicol, but were susceptible to apramycin , amikacin and polymyxin E. While most of the O64 strains possessed astA and Stx2e, and also were resistant to ciprofloxacin, enrofloxacin, chloramphenicol and sulfamethoxazol, but were susceptible to kanamycin and polymyxin E. 【Conclusion】 It is concluded that O8 and O64 are dominant serogroups associate with the disease of swine, both serogroups harbor similar virulence genes and resistant phenotypes, but present different susceptibility phenotypes.

    Changes of Acute Phase Proteins Profile in PCV2 Experimentally Infected Piglets

    SUN Yun,HUA Li-zhong,CHEN Geng,ZHANG Shu-xia
    Scientia Agricultura Sinica. 2010, 43(19):  4116-4122 .  doi:10.3864/j.issn.0578-1752.2010.19.026
    Abstract ( 710 )   PDF (348KB) ( 765 )   Save
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    【Objective】 In order to obtain the valuable evidence of pathogenic mechanism and clinical diagnosis about PCV2 infection, the dynamic changes of acute phase proteins (APPs) concentration in serum and APPs expression in liver were studied in piglets infected with PCV2. 【Method】Nineteen conventional piglets without antibodies against PCV2, obtained from a farrow-to-finish farm and certified as having a health status, were divided into control group and challenge group, at randomly. Their blood and liver tissues were collected at different days post-inoculation (DPI) of PCV2. The dynamic changes in concentration of APPs were detected by ELISA, and its mRNA expression in liver were evaluated using fluorescence quantitative RT-PCR, respectively. The histopathological changes of liver lesions were also observed. 【Result】 After PCV2 infection, there were variable degrees of pathological lesions of parenchymal cells in livers, vacuolar degeneration in hepatocytes, proliferation of connective tissue in perilobuler area, and variable degrees of eosinophilic granulocyte infiltration in the perilobular and parenchymal area. The maximum values of pig-main acute phase protein (pig-MAP) were reached on 7 DPI, a significant increase with respect to the serum concentrations before infection (0 DPI)(P<0.05), and the values were gradually recovered to baseline after 14 DPI. Serum amyloid A (SAA) concentration had a significant increase on 7 and 21 DPI compared to the pre-infection (P<0.05). Apolipoprotein-AⅠ (ApoA-Ⅰ) was significantly increased on 21 DPI (P<0.05). There was an increasable tendency of haptoglobin (HP), C-reactive protein (CRP), alpha-1 acid glycoprotein (AGP) and SAA mRNA on 21 DPI. 【Conclusion】 The main histopathological lesions of liver were hepatocytes degeneration and necrosis, connective tissue proliferation in piglets infected with PCV2. The APPs showed different levels in concentration in serum and expression profile in livers. Among them, Pig-MAP could be a valuable marker for monitoring the course of PCV2 infection and prognosis.