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Table of Content

    10 September 2007, Volume 40 Issue 9
    CROP GENETICS & BREEDING·GERMPLASM RESOURCES
    Establishment of a Gene Expression System in the Rice Chloroplast and Obtainment of PPT-resistant Rice Plants
    Scientia Agricultura Sinica. 2007, 40(9):  1849-1855 . 
    Abstract ( 1327 )   PDF (455KB) ( 1276 )   Save
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    【Objective】The aim of this study was to establish an expression system for foreign genes in rice chloroplast genome.【Method】By analyzing the published complete nucleotide sequence of rice chloroplast genome and its gene distribution pattern, the intergenic region of ndhF and trnl on chloroplast genome was selected as target for site-specific integration of PPT-resistant bar gene. Two fragments were cloned from rice chloroplast genome DNA by using PCR technique, which were suitable for homologous recombination in the genetic transformation of rice genome. A gene expression cassette was generated by fusing a modified 16S rRNA gene promoter to bar gene and using 3’ sequence of psbA gene as terminator. Based on this cassette and the cloned homologous fragments, the chloroplast-specific expression vector pRB was constructed. 【Result】Chloroplast transformation was carried out by biolistic bombardment of sterile rice calli with plasmid pRB. Subsequently, the regenerated plantlets, and seeds of progeny arising from reciprocal cross to the wild-type lines, were obtained. Molecular analysis on the transformed plants indicated that foreign gene bar has been integrated into rice chloroplast genome in a site-specific way. Genetic analysis with seeds of progeny revealed that bar gene expressed normally in rice chloroplast genome, and could be stably transmitted into next generation. 【Conclusion】Therefore, it was suggested that an efficient gene expression system in the rice chloroplast has been established by chloroplast transformation technique. The bar gene conferred not only selection pressure for the transformation of rice chloroplast genome, but PPT-resistant trait for rice plants as well.
    Patterns of Positive Selection and Gene Gonversion in the Complete Disease Resistance genes of Rice
    Scientia Agricultura Sinica. 2007, 40(9):  1856-1863 . 
    Abstract ( 1519 )   PDF (414KB) ( 1948 )   Save
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    We performed a genome-wide analysis of positive selection and gene conversion in members of the nucleotide binding site (NBS)-LRR gene family of Oryza sativa L. var. Nipponbare. Analyses were possible for 172 of 457 NBS-LRR genes in the genome, and the analyses uncovered substantial evidence of positive selection and gene conversion. Sites under positive selection were detected and identified for 19 sequence groups representing 89 NBS-LRR genes and approximate 60% of positively selection sites were located in the LRRs region. At least one gene conversion event was detected in 56 NBS-LRR genes. Positively selection sites were identified in 84% of genes which were detected in a gene conversion event. Most of the genes detected in positive selection or gene conversion were resided in gene clusters.
    Study on Quality of NILs possessing HMW-GS Null and 1 in Wheat cv. Longfumai 3
    Scientia Agricultura Sinica. 2007, 40(9):  1864-1870 . 
    Abstract ( 1152 )   PDF (276KB) ( 942 )   Save
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    Abstract:【Objective】 In order to determine the genetic differences between high molecular weigh glutenin subunits (HMW-GS) Null and1.【Method】HMW-GS 1 was introduced into Longfumai 3(N,7+8,5+10) by 5 consecutive backcrosses with biochemical marker assisted selection. The near isogenic lines (NILs) of HMW-GS Null and 1 were obtained and grown in the experimental field of Crop Breeding Institute of Heilongjiang Academy of Agricultural Science in 2004 and 2005, the experimental design was method of pairing arrangement with four replicates. 【Result】The result of two years showed that the statistic differences of quality parameters between Longfumai 3 with 1 subunit and Longfumai 3 with Null subunit was no significant in flour protein content, dry gluten content, water absorption. The gluten index, Zeleny sedimentation, the ratio of sedimentation/dry gluten, development time, stability and Breakdown time in the 1 NILs were 5.8%(P<0.01)、9.3%(P<0.01)、8.6%(P=0.01)、127.3%(P<0.01)、79.2%(P<0.01)、53.6%(P<0.01) higher than that in the Null NILs, respectively, while the ratio of wet gluten/dry gluten and degree of softening were 1.7%(P=0.05)、16.5%(P=0.13) lower, respectively. 【Conclusion】The impact of the HMW-GS 1 on gluten strength was highly positive in NILs containing HMW-GS 5+10, suggesting that HMW-GS 1 are a of the necessary subunits to breeding strong gluten wheat.
    Variation of major mineral elements content and their relationships in Chinese wheats
    Scientia Agricultura Sinica. 2007, 40(9):  1871-1876 . 
    Abstract ( 1424 )   PDF (202KB) ( 1485 )   Save
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    Mineral elements including micronutrients as Fe and Zinc are very essential for human life. Two hundred and forty cultivars and advanced lines, originated from Beijing, Heibei, Henan, Shandong, Shanxi, and Shaanxi Provinces, were collected and sown in the experiment station of Crop Science Research Institute, in Chinese Academy of Agriculture Sciences in 1997-1998 wheat season, to evaluate the contents of major mineral elements including micronutrients as Fe, Ze, Mn, Cu, and macronutrients as Ca, Mg, K, P, S. Large variation for most of the mineral elements contents except Mg and S, and big difference between cultivars for all the mineral elements contents were observed. Among the micronutrients, Fe performed the highest average content, with value being of 41.9 mg/Kg, while the lowest for Cu, with value being of 5.54 mg/Kg. Among the macronutrients, K had the highest average content, with value being of 4747 mg/Kg, while the lowest for Ca, with value being of 465 mg/Kg. There were large differences for the mineral elements contents among cultivars with different origin, with cultivars from Beijing and Shandong performed high contents for most of the micronutrients, cultivars from Hebei and Shandong had high contents for most of the macronutrients, while cultivars from Henan Province had the lowest content for most of the mineral elements including micro- and macronutrients. Highly significant positive correlations between the contents of Fe and Zn (r = 0.630), Mg and P (r = 0.571), Mg and S (r = 0.521), Zn and P (r = 0.502), and P and S (r = 0.537) were also observed, indicating possibility for elevating these mineral elements contents at the same time. There was obvious pedigree relationship among the cultivars and advanced lines with high content of mineral elements as Fe and Zn, suggesting that parents with high mineral elements content and grain yield should be used first of all in crossing with the main objective being to improve mineral elements contents in wheat breeding program. It also indicated that in the current situation leading cultivars should be screened for mineral elements contents in order to be used directly of indirectly in wheat breeding program economically and effectively.
    Cloning of proteinase inhibitor gene StPI in diploid potato and its expression analysis
    Scientia Agricultura Sinica. 2007, 40(9):  1877-1882 . 
    Abstract ( 1414 )   PDF (310KB) ( 930 )   Save
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    A full-length cDNA of proteinase inhibitor (PI) homolog with completed open reading frame of 116 amino acids was cloned from Ralstonia solanacearum resistant potato leaves using rapid amplification of cDNA ends (RACE) method and designated as StPI. BLAST search against NCBI showed that the StPI gene shared 89% identity with potato proteinase inhibitor I precursor in nucleotide and 74% in amino acid. Analysis of semi-quantity RT-PCR indicated that this gene was induced by Ralstonia solanacearum as well as up-regulated by jasmonic acid (JA), and its expression reached the highest level before 12h post R. solanacearum inoculation or JA-treatment, then leveled off. Moreover, this gene was strongly induced by JA and its mRNA accumulation quantity increased quickly post JA treatment. It concludes that StPI gene may play a role in potato resistance against R. solanacearum. and the inducyion of StPI by R. solanacearum invasion may have a similar signal transduction pathway with JA treatment.
    Gene Cloning and Structural Analysis of Biotin Carboxyl Carrier Protein Encoding Gene in Brassica napus
    Scientia Agricultura Sinica. 2007, 40(9):  1883-1889 . 
    Abstract ( 1631 )   PDF (292KB) ( 1077 )   Save
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    Gene Cloning and Structural Analysis of Biotin Carboxyl Carrier Protein Encoding Gene in Brassica napus DAI Xiao-feng, LU Chang-ming, WU Gang, WU Yu-hua, Xiao Ling (Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan, Hubei, China, 430062) Abstract: Acyl-CoA carboxylase (ACCase) catalyzes the first step in the de novo biosynthesis of fatty acids. Biotin carboxyl carrier protein (BCCP), being one of the subunits of plastidial ACCase, controls the transferring of carboxyl from acetyl-CoA carboxylase to carboxyltransferase. In this study, we isolated bccp genes from genomic DNA of three winter-type cultivars of Brassica napus and analyzed their structural aspects of these genes in both DNA and protein levels, including length, intron distribution, hydrophobic conserved regions etc.. Results showed that there were at least 3 isoforms of bccp genes found in genomes of B.napus. Only one isoform bccp1 encodes a protein which is full in length and contains the domain for biotinylation, while the other two isoforms bccp2 and bccp3 encode proteins that are incomplete and lack of the domain for biotinylation. Further analysis revealed that both in bccp2 and bccp3 an adenine insertion resulted in a shift-frame mutation. This research provides scientific basis of bccp genes for genetic engineering and molecular marker-assisstant breeding.
    TILLAGE & CULTIVATION·PHYSIOLOGY & ECOLOGY
    Characteristics of Sugar Degradation and Starch Accumulation in Waxy Wheat Grains after Anthesis
    Scientia Agricultura Sinica. 2007, 40(9):  1890-1897 . 
    Abstract ( 1259 )   PDF (277KB) ( 956 )   Save
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    Abstract: 【Objective】 The aim of this experiment is to discover the characteristics of sugar degradation and starch accumulation in waxy wheat by comparing its grain soluble sugar content and starch content with non-waxy wheat, and by studying the dynamics of sugar degradation, starch accumulation in waxy wheat grains after anthesis. 【Method】 Soluble sugar content and starch content in grains of 17 waxy wheat varieties from different crosses and 4 non-waxy wheat varieties(check) were determined in 2004-2005, and 3 waxy varieties and 2 check varieties were selected to study the process of sugar degradation and starch accumulation in grains after anthesis in 2005-2006 . 【Results】In terms of grain soluble sugar content, 15 waxy wheat varieties were significantly greater than all check varieties, and the other 2 waxy wheat varieties were significantly greater than Yangmai 12 and Yangmai 5. As grain starch content, all waxy wheat varieties were lower than Yangmai 9, 4 of which were higher than Yangmai 158. There was no significant difference in grain starch content among check varieties, although Yangmai 158 was lower than Yangmai 9, Yangmai 5 and Yangmai 12.The decreasing rate of soluble sugar content in waxy wheat grains was slow during the period from the 10th day to the 17th day after anthesis. All 3 waxy wheat varieties tested had a “pause stage” of starch content increase after the 17th day post-anthesis, during which starch content stopped increasing. 【Conclusion】Soluble sugar content in waxy wheat grains was higher, but starch content was lower than check varieties. The probable reason might be the low efficiency of sugar transformation at the beginning stage of grain filling and the existence of “pause stage” due to the absence of GBSS. Much attention should be paid to study on the efficiency of sugar transformation and the process of starch accumulation, so as to breed varieties with high efficiency of sugar transformation and late appearing of “pause stage” during starch accumulation.
    Photosynthetic Traits of over-15000 kgha-1 Summer Maize Hybrids during Grain Filling
    Scientia Agricultura Sinica. 2007, 40(9):  1898-1906 . 
    Abstract ( 1244 )   PDF (554KB) ( 1206 )   Save
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    【Objective】It is very important to study photosynthesis of super high-yielding maize hybrids, so a field trail was conducted to research the relation to photosynthetic traits and yield of over-15000 kg ha-1 summer maize hybrids during grain filling period. 【Method】Three summer maize hybrids (XY335, DH3632 and DH3806) were planted at 78000 plants ha-1 in National Corn Project Technology Research Center (Shandong) randomly. Above-ground biomass partitioning and photosynthetic characteristics of ear leaves were investigated to evaluate yield formation of three super high-yielding maize hybrids during grain filling period.【Result】Yields of three-type maize hybrids were over 15000 kg ha-1, and yield of XY335 was higher than that of DH3632 and DH3806 significantly (P<0.05). Characteristic of grain filling analyzed by Richards equation showed XY335 had the higher grain-filling rate, the longer active growing period, and it reached the maximum grain-filling rate earlier than DH3632 and DH3806. The result indicated grain-filling traits like XY335 was favorable to high yield in the experiment. The leaves’ photosynthetic physiology quantity of XY335 was highest of the three-type hybrids. XY335 had high net photosynthetic rate (Pn), PEPCase activity, RuBPCase activity and chlorophyll a/b value after anthesis, and the leaf area index (LAI) and soluble protein content decreased slowly from 20d and 30d after flowering, respectively. 【Conclusion】To obtain 15000 kg ha-1 of super high-yielding breeding and cultivation in practice, we need to improve the leaves photosynthetic physiology quantity to maintain high grain-filling rate and long active growing period after anthesis, enhance the solar energy use efficiency.
    Study on characteristics of wheat canopy reflectance and wheat yield caused by variable nitrogen application based on Spectral index
    Scientia Agricultura Sinica. 2007, 40(9):  1907-1913 . 
    Abstract ( 1117 )   PDF (248KB) ( 1101 )   Save
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    This study was to develop the time-specific and time-critical method to overcome the limitations of traditional field sampling methods for variable rate fertilization. Farmers, agricultural managers and grain processing enterprises are interested in measuring and assessing soil and crop status in order to apply adequate fertilizer quantities to crop growth. This paper focused on studying the relationship between vegetation index (OSAVI) and nitrogen content to determine the amount of nitrogen fertilizer recommended for variable rate management in precision agriculture. The uniform rate fertilizer management was chosen as the CK. Analyses revealed that the red edge of the wheat canopy reflectance spectrum had distinct “red shift” and increased red peak in variable-rate zones. The variable-rate nitrogen fertilization reduced the variability of wheat yield and OSAVI and increased wheat yield, compared to uniform rate fertilizer application. There was a big difference for canopy spectral reflectance between two nitrogen application types in wavebands of 670nm and 760-900nm at elongation stage.
    The analysis of conservation tillage in China----conservation tillage and crop yield: reviewing the evidence
    Scientia Agricultura Sinica. 2007, 40(9):  1914-1924 . 
    Abstract ( 1532 )   PDF (337KB) ( 586 )   Save
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    【Objective】Conservation tillage (CT) also be referred to as resource-efficient / resource effective agriculture,it is primarily used as a means to protect soils from erosion and compaction, to conserve moisture and reduce production costs, have become the most important measures of sustainable agriculture development. Research advances in the conservation tillage of china on recent years were reviewed in this paper.【Method】Based on papers published, the current researches progress on conservation tillage (CT) of crop production in china were summarized and analyzed. All these aspects are reviewed but detailed information of conservation tillage is spares and disparate from China studies.【Result】It was showed that conservation tillage is a relatively new concept but widely adopted in china and had considerable benefits. Since studies have been conducted at the catchment scale, therefore some findings must be treated with caution until the can be verified at a larger scale and for a greater range of climatic, cropping and soil conditions.【Conclusion】Conservation tillage should be put forward in order to establish reasonable policy of agricultural management. It necessary using integrated system analysis methodologies, by means of long-term field and theoretical experience, and the developed modeling approaches with interdisciplinary knowledge, to enhance research strength and level for improving and promoting sustainable agricultural.
    PLANT PROTECTION
    Postulation of Leaf Rust Resistance Genes in 47 New Wheat Cultivars(Lines)in China
    Scientia Agricultura Sinica. 2007, 40(9):  1925-1935 . 
    Abstract ( 1108 )   PDF (701KB) ( 527 )   Save
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    【Objective】The objectives of this study were to postulate leaf rust resistance genes in 47 new wheat cultivars(lines)in China, and to analyse problems of postulations and their application and realization.【Method】With seventeen differential pathotypes being tested under different temperature and (or) light intensity, genes were detected with pedigree analysis. Postulation results were intensively analyzed.【Result】Ten named genes, Lr1(in 11 cultivars or lines), Lr3(8), Lr3bg(2), Lr9(3), Lr10(4), Lr13(10), Lr16(6), Lr23(2), Lr26(14), and Lr34(1), were identified. Unnamed genes were found in forty-two cultivars(lines).【Conclusion】Reliable results could only be obtained from more differential pathotypes, repeated determination under relatively steady and uniform environment, and pedigree analysis.
    Review on the Genetic Structure of Potato Late Blight Pathogen (Phytophthora infestans(de Bary) Population
    Scientia Agricultura Sinica. 2007, 40(9):  1936-1942 . 
    Abstract ( 1187 )   PDF (224KB) ( 1170 )   Save
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    Phenotypic characteristics of Phytophthora infestans population, such as mating type, physiological race and metalaxyl-sensitivity were reviewed. The distribution of A2 mating type, physiological race structure and the frequency of resistant isolate to metalaxyl in different countries were described. Research results about the genotype and genetic diversity of Phytophthora infestans with the molecular markers including mtDNA fingerprint, RFLP, RAPD, AFLP and SSR were discussed. The research focus of potato late blight pathogen in China was suggested.
    Studies on prunus necrotic ringspot Ilarvirus(Prunus necrotic ringspot virus,PNRSV) occurred on Lily
    Scientia Agricultura Sinica. 2007, 40(9):  1943-1951 . 
    Abstract ( 1338 )   PDF (705KB) ( 506 )   Save
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    【Objective】Molecular Identification of Prunus necrotic ringspot virus occurred on Lily. 【Method】Lily corms were randomly selected and grown in greenhouse. Total RNAs were extracted from younger leaves with RNA Extraction Kit (Sangon, China), and RT-PCR amplification of CP cDNA fragments was performed with primer pairs specific for PNRSV. An expected cDNA fragment of about 450bp was harvested and cloned into pGEM-T-easy Vector. Clones were sequenced and compared with reported PNRSV isolates in Gene bank【Result】The nucleotide sequence of the cloned cDNA revealed that 450bp sequence is belong to PNRSV, and has a 84.5%~99.1% homology with 27 reported PNRSV isolates.【Conclusion】Identifying the occurrence of Prunus necrotic ringspot virus on Lily with molecular bio-methods, and confirming that lily is a new nature host of PNRSV.
    Separation of Insecticidal Active Ingredient of Paecilomyces Cicadae(Miquel)Samson
    Scientia Agricultura Sinica. 2007, 40(9):  1952-1958 . 
    Abstract ( 1562 )   PDF (404KB) ( 1127 )   Save
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    Insecticidal active substance of the fruiting body of Paecilomyces Cicadae(Miquel)Samson was isolated and purified by combined with separation and analyzing and biology experiment for the first time. The results showed that the water portion of ethanol-H20 total extract was strong toxicity to against the third instar larvae of Plutella xylostella L. in 24h, 48h and 72h with the corrective mortality of 46.67±1.34%、60±2.24% and 66.67±1.79%, respectively, at the concentration of 50.0mg/ml, and the other fractions of CH2Cl2, ethyl acetate and n-butanol were weak. By means of bioactive guided isolation of macroporous adsorption resin column, high performance liquid chromatography and sephadex A-20 column, a white powder compound was obtained. At the concentration of 10.0mg/ml, the corrective mortality of the compound against Plutella xylostella L were significantly ( P < 0101), 95.12±1.83%, 97.67±1.60% and 99.06±1.68%, respectively, in 24h, 48h and 72h. The bioactive compound was stable to acids and was not sensitive to proteinase pepsin, other physical and chemical chractristics were reported.
    Adsorption of abamectin in soil-water environment
    Scientia Agricultura Sinica. 2007, 40(9):  1959-1963 . 
    Abstract ( 1131 )   PDF (306KB) ( 957 )   Save
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    Adsorption of abametin in 5 different soils was studied by batch equilibration technique. The result showed that soils had strong adsorption of abamectin, which, however, varied with the different properties of the soil tested. The isotherm data were fitted to Fruendlich equation, The Kaf values increased with increasing organic matter and clay content of soil, the correlative coefficient of Kaf values and organic matter and clay content of soil were significantly positive .The free energy of sorption ranged from 10.9859 kJ/mol to 25.1538 KJ/mol indicates that the spontaneity of the given sorption process of abamectin in soils.
    SOIL & FERTILIZER·WATER-SAVING IRRIGATION
    Movement and Aftereffect of Labeled Nitrate-N in Different Soil Layers
    Scientia Agricultura Sinica. 2007, 40(9):  1964-1972 . 
    Abstract ( 1497 )   PDF (420KB) ( 1125 )   Save
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    Abstract: This study set up field micro-plot experiments by technique of external injection of labeled 15NO-3-N to investigate the movement and aftereffect of labeled nitrate-N in different soil layers. The results showed that,under the condition of experimental water and nitrogen management, in the crop growth season no NO-3-N intensively poured, labeled NO-3-N in soil depth of 15cm, 45cm and 75cm moved downwards 65cm, 45cm and 25cm respectively, which no moved outside crop root zone (1m). These presented the regulation of labeled NO-3-N in upper soil layer moving in longer distance and those in subsoil in shorter distance. Labeled NO-3-N dynamic regulation in soil solution 100 cm depth frankly reflected N utilization status. From after-sowing to before-winter, labeled NO-3-N concentration in those three treatments changed less. But at the growth-evening stage, for wheat it increased in soil depth of 15 cm and 45 cm and for two crops it increased in 75 cm layer until harvest, which showed that N utilization in 75 cm soil layer were lower. In summer maize growth season, labeled-N utilization ratio was from 2.1% to 5.6%. The remnant efficiency in different labeled-N treatments collectively represented higher in soil depth of 45 cm and lower in 15 cm and 75 cm. And in summer maize planted behind Jin411 it was significantly higher than those planted behind Xiaoyan54 in soil depth of 15 cm and 45 cm, the value in the former was higher than those in the latter in soil depth of 75 cm, but no significant.
    Effects of conservation tillage on the soil aggregates characteristics in Huabei Plain, China
    Yizhong Lv Hu Zhou Zhichen Yang Baoguo Li
    Scientia Agricultura Sinica. 2007, 40(9):  1973-1979 . 
    Abstract ( 1412 )   PDF (265KB) ( 1509 )   Save
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    【Objective】Tillage will greatly influence the aggregation and stability of soil aggregates. The paper studied the effects of conservation tillage on the soil aggregates characteristics. 【Method】Soils from No-tillage (NT), Rotary tillage (RT) and conventional tillage (Moldboard tillage, CT) plots witch lasted 4 years (2001-2005) at the Luancheng Research Station in Hebei Province were sampled, and the aggregates amount, size distribution and fractal dimension were examined by dry and wet sieving methods. 【Result】Results indicated that NT significantly increased the topsoil (0-5cm) bulk density (BD), while RT maintained lower BD as CT except for significant increase at 10-20cm. Dry sieving results showed that NT resulted in higher Macro-aggregates content (R0.25), mean weight diameter (MWD) and Geometric Mean Diameter (GMD) than other treatments at 0-10cm, while RT showed no difference with CT. Wet sieving results showed that most of the aggregates are unstable, and the MWD and GMD of water-table aggregates showed the same trend: NT>RT>CT. At 0-5cm, the fractal dimension (D) of water-stable aggregates under NT was lower than RT and CT; while at 5-10cm, RT yielded highest , showed worst stability. 【Conclusion】After 4 years experiment, NT increased the aggregation and the stability of soil aggregates, while duo to intense disturbance, the aggregation and stability within tillage depth under RT and CT decreased; at 10-30cm, no significant difference had been yielded among the three tillage systems.
    Study on the spatial variability of the soil cation exchange capacity in hilly tea plantation soils with different sampling scales
    Scientia Agricultura Sinica. 2007, 40(9):  1980-1988 . 
    Abstract ( 1333 )   PDF (417KB) ( 862 )   Save
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    Abstract: Studies about the spatial variability of the soil cation exchange capacity (CEC) could provide the construction of ecological tea plantation and management of soil fertilizer in tea plantation with some theoretical basis. Geostatistics were used for the analysis of the spatial variability of soil CEC in tea plantation at mountain of Mengding in Sichuan province with two sampling scales. Results:(1)In the tea plantation at small scale, the soil CEC was consumingly spatially dependent, the rate of nugget to sill was18.84%, the range of spatially dependent was 1818m. Structural factors were the main factors which affected the spatial variability of the soil CEC. The soil CEC had a stronger anisotropic structure in the aspect of the slope, and a weaker one at the aclinic aspect of the slope. According to the Ordinary Kriging method the equivalence of the soil CEC was distributed along the aclinic aspect of the slope from northeast to southwest, and the soil CEC content was reduced as the elevation went down. (2) In the tea plantation at micro scale, the soil CEC was consumingly spatially dependent too, and the rate of nugget to sill was16.52%, the range of spatially dependent was 311m. Structural factors were the main factors which affected the spatial variability of the soil CEC.The anisotropic Structure was different with the small scale, It had a stronger anisotropic structure in the aspect which near the aspect of slope,and a weaker one near the aclinic aspect of the slope. The soil CEC distributed along the aclinic aspect of the slope and some distributed like spots. From top to down of the slope,the soil CEC increased firrst,then reduced, and finally increased.
    Prediction and validation of soil organic matter content based on hyperspectrum
    Scientia Agricultura Sinica. 2007, 40(9):  1989-1995 . 
    Abstract ( 1509 )   PDF (518KB) ( 1165 )   Save
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    NIR-Visible spectral reflectance of soil samples were measured using ASD2500 hyperspectral meter. The results indicated that the spectral reflectance curve shape of north-east black soil of Heilongjiang is different from fluvo-aquic soil of Henan and Shandong province. The former shows ascending in a slow curve but the latter in a steep curve in 600-900nm region. The correlation analysis indicated that organic matter (OM) content has negative correlation with spectral reflectance in 545-830nm at 0.05 significant level and in 580-738nm at 0.01 significant level. OM has positive correlation with first derivative spectral reflectance in 458-1069nm and 1166-1306nm at 0.01 significant level. Furthermore, the degree of correlation is stronger than original spectral reflectance. Different spectral characteristic parameters are selected including reflectance and its first derivation, reflected height and absorbed depth. The analysis results show that OM can be predicted using first derivative reflectance in 570-590nm and reflected height in 1280nm (P_Depth1280). By validating, the prediction models are practical and feasible. Different models can be made reference to each other in practice.
    Research of Management zones Generating Based on QuickBird Imagery
    Xiao-yu Song Tao Shen
    Scientia Agricultura Sinica. 2007, 40(9):  1996-2006 . 
    Abstract ( 1327 )   PDF (472KB) ( 821 )   Save
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    Abstract::【OBJECTIVE】This present study tries use high-resolution multi-spectral remote sensing data-Quickbird imagery to generate within-field management zone.【METHOD】After spatial analysis of soil nutrient sampling data, three methods of management zone generating were evaluated in this study: 1)using of soil nutrient sampling data to generate management zone map;2)using of crop remote sensing information to generate management zone map;3)using of soil nutrient data and crop remote sensing information to generate management zone map.【RESULTS】Results indicate that using remotely sensed data and soil property data reduced the variance of soil property and spectral parameters within management zone compared with field scale soil property variability. 【CONCLUSION】Results show that it is valid to use remotely sensed data to generate management zone.
    HORTICULTURE
    Accumulation of nitrate in vegetables and its possible implications to human health
    Scientia Agricultura Sinica. 2007, 40(9):  2007-2014 . 
    Abstract ( 1544 )   PDF (393KB) ( 2154 )   Save
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    Recently,there are two kinds of completely opposite viewpoints about the effects of nitrate on human health. In order to further understand objectively the effects of nitrate on human health, both of harmfulness and possible benefits of nitrate to human body were discussed in this review from the aspects of nitrate accumulation in vegetables, the source of nitrate ingested into human body and the transformation of nitrate in human body as well as the pathogenesis and physiological functions of nitrate metabolins.
    Identification in Transgenic Lines of Malus robusta by Introducing LeIRT2 Gene
    Scientia Agricultura Sinica. 2007, 40(9):  2015-2020 . 
    Abstract ( 1344 )   PDF (333KB) ( 871 )   Save
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    Nine transgenic plants of Malus robusta were confirmed by Southern blot analysis. The results indicated that one to three copies of the transgene were integrated into the plant genomes respectively, were hydroponically The half fix quantify RT-PCR were carried out to identify transcription of LeIRT2 gene, six carrying one copy of the transgene were successful transcript. Planted to test their efficiency to iron-deficiency, and the tolerance was only found in the transgenic plant4 and 5 with single copy. The rate of root H+ excretion increased in transgenic lines and were substantially higher than those of control. The Fe、Mn、Zn content of leaves and roots of the transgenic lines and non-transgenic plants under the hydroponic experiment in iron-deficient full-strength solution medium with NaFeEDTA 1.00×10-6 mol/L was determined. The total Fe content of the transgenic ling roots and the activated Fe content of the transgenic leaves were notably increased. The Zn content of the transgenic line leaves and roots were notably increased too, but the Mn content was failed to increase. Using LeIRT2 gene from plasmid as the probe, the expression of LeIRT2 in the transgenic malus robusta during iron deficiency was investigated with tissue printing mRNA Northern hybridization. Strong hybridization signals were observed in the leaves and roots of the transgenic malus robusta which had been exposed to iron stress for 5 days.
    The RAPD marker linked to precocious gene of walnut (Juglans regia L.) and its sequence analysis
    Scientia Agricultura Sinica. 2007, 40(9):  2021-2027 . 
    Abstract ( 1158 )   PDF (528KB) ( 1058 )   Save
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    Abstract:【OBJECTIVE】To identify the genetic distance between RAPD marker OPB-08900 and precocious gene of walnut (Juglans regia L.), and character the sequence of OPB-08900; 【METHOD】The template DNA extracted from precocious maternal parent Lüyuan、later mature paternal parent Lüfeng and 154 F1 hybrid plants were screened with OPB-08 primer (5′GTCCACACGG 3′). The genetic distance between OPB-08900 and precocious gene of walnut was calculated using Haldane function .DNA fragments of OPB-08900 derived from precocious F1 hybrid No.2 was retrieved from agarose gel and ligated into pMD18-T Vector, and then transformed into E. coli JM109. Sequencing of positive clones was carried out .The restriction sites of sequence OPB-08958 analyzed by DNAMAN and BLAST in nr database of GenBank;【RESULTS】The RAPD-PCR result showed that specific fragment OPB-08900 was presented in precocious maternal parent Lüyuan and 69 F1 hybrid plants, but was absented in later mature paternal parent Lüfeng and 82 F1 hybrid plants . The RAPD marker OPB-08900 was co-segregating with precocious trait of walnut and the genetic distance between OPB-08900 and precocious gene was 1.99 cM. The sequencing result showed the RAPD marker OPB-08900 was 958bp, so RAPD marker OPB-08900 should be renamed OPB-08958,GenBank accession number is DQ673614.There were 97 restriction sites in the sequence of OPB-08958, digested by 36 restriction enzymes; The sequence of OPB-08958 was not homologous with any plants in GenBank;【CONCLUSION】The precocious trait of walnut is controlled by more than 2 genes which were dominance. RAPD marker OPB-08958 linked to one of the precocious genes and the sequences of OPB-08958 is unique to Walnut genome.
    Simulation of Development and Growth of Greenhouse Single Flower Cut Chrysanthemum II. Modelling of Dry Matter Production and Partitioning
    Scientia Agricultura Sinica. 2007, 40(9):  2028-2035 . 
    Abstract ( 1645 )   PDF (467KB) ( 876 )   Save
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    【OBJECTIVE】Dry matter production and partitioning is the base of external quality formation of cut chrysanthemum. A simulation model was developed to predict the biomass production, dry weight of organs and shoot fresh and dry weight of single flower cut chrysanthemum for the optimization of crop and climate management for greenhouse single flower cut chrysanthemum production.【METHOD】A model of dry matter production and partitioning of greenhouse single flower cut chrysanthemum was developed based on the effects of temperature and radiation on chrysanthemum growth. Experiments with different varieties and planting dates were carried out in greenhouses, to collect data to develop and validate the model. 【RESULTS】The results show that the simulated value agree well with the observed ones. The determination coefficient (R2) and root mean squared error (RMSE) between the simulated and the measured value based on the 1:1 line for biomass production, dry weight of leaf, stem and flower, and fresh weight of shoot per plant were, respectively, 0.97, 0.97, 0.97, 0.83, 0.99; 67.56g·m-2, 0.35, 0.44, 0.24 and 3.73 g·plant-1. For the prediction of biomass production, the prediction accuracy of the PTEP based model is significantly higher than that of the photosynthesis process based crop growth model ( R2 and RMSE were 0.82和274.68 g·m-2 , respectively ). 【CONCLUSION】 Based on the results obtained in this study, it can be concluded that the model developed in this study can give satisfactory prediction of greenhouse single flower cut chrysanthemum biomass production and partitioning. Compared with the photosynthesis process based crop growth model, the model developed in this study is more applicable for the optimization of climate and crop management for greenhouse cut chrysanthemum production.
    Construction and Application of Evaluating Quantitatively System of Appearance Quality of Flue-cured Tobacco
    Scientia Agricultura Sinica. 2007, 40(9):  2036-2044 . 
    Abstract ( 1266 )   PDF (447KB) ( 1173 )   Save
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    【Objective】Technological support was offered for perfecting the system of flue-cured tobacco quality evaluation and establishing regional assignment of tobacco planting by constructing the evaluating quantitatively system of appearance quality of flue-cured tobacco and being verified preliminarily. 【Method】The evaluating quantitatively system of appearance quality of flue-cured tobacco was constructed by adopting expert consultation, factor analysis, cluster analysis, fuzzy mathematics, statistical description, analysis of variance, analysis of correlation, geo-statistical analysis et al with flue-cured tobacco samples from tobacco-growing areas of Hunan in 2005, the correlation of evaluating indexes of appearance quality and region characteristic of appearance quality of flue-cured tobacco in Hunan were analyzed by that.【Result】There are extreme significance positive correlation between evaluating indexes of appearance quality. Evaluating indexes of appearance quality was clustered to 3 types: chroma, chromatic homogeneity, oil; mature, growth status, leaf structure, body; smooth or green-yellow. The sequence of the appearance quality score: X2F<B2F<C3F, and the score difference was extreme significance in different grades. There was not statistical difference of appearance quality score in different varieties. The sequence of the appearance quality score: Xiangnan<Xiangzhong<Xiangxibei, and the score difference was extreme significance in different ecological regions. The appearance quality index in spatial distribution reduced gradually from the high score area in west Hunan to the low score area in east Hunan, and the spatial difference of appearance quality index was distinctness. The styles of appearance quality of flue-cured tobacco in Hunan concentrate mainly on number three and number two, and less on number one. The difference of styles of appearance quality was distinctness in different grades and ecological regions.【Conclusion】The rationality of evaluating quantitatively system of appearance quality of flue-cured tobacco constructed by adopting expert consultation, factor analysis, fuzzy mathematics was verified, and that was doable to evaluate synthetically the region characteristic of appearance quality of flue-cured tobacco.
    Comparative Study on the Antioxidant Stability of Anthocyanin Extracts in Seed Coats of Three Black Cereal and Oil Crops
    Scientia Agricultura Sinica. 2007, 40(9):  2045-2052 . 
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    The effects of external factors and five sterilizing processes on the stabilities of total antioxidant capacities (TAC) in three anthocyanin extracts of black rice, black soybean and black corn by colorimetry and ferric reducing ability method were investigated. The results showed that the TAC of anthocyanin extracts from seed coats of black rice, black soybean and black corn displayed the photosensitive characteristics that decreased with the prolonging of illumination; under the conditions of natural light, fluorescent light, and without illumination, the TAC stability was in the order of black rice anthocyanin (BRA), black soybean anthocyanin (BSA), and black corn anthocyanin (BCA); the TAC of these three anthocyanin extracts displayed the heat sensitive characteristics that decreased with the prolonging of heating time, and the higher the temperature, the more they were decreased; the TAC stability was in the order of BSA, BRA and BCA. There were no significant effects of food materials such as NaCl, sucrose, and glucose and preservative sodium benzoate on the TAC stabilities of these three anthocyanin extracts, while there were different effects of five metal ions of K+, Ca2+, Mg2+, Zn2+, and Cu2+ on the TAC stabilities of these three anthocyanin extracts; the TAC stabilities of these three anthocyanin extracts were significantly affected by five sterilizing processes of boiling sterilization, autoclave sterilization, pasteurization, microwave sterilization, and high temperature short time sterilization, of which they were least affected by high temperature short time treatment, and most affected by autoclave sterilization.
    ANIMAL SCIENCE·VETERINARY SCIENCERE·SOURCE INSECT
    Study on SLA Class I-3 Alleles for Inbreeding WZSP
    SUN Jun-li MU Yu-lian LIU xiao-lin WANG Su-rong
    Scientia Agricultura Sinica. 2007, 40(9):  2053-2061 . 
    Abstract ( 1165 )   PDF (1058KB) ( 967 )   Save
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    To elucidate the structure of SLAⅠ3 alleles on inbred line of Wuzhishan pig(WZSP) population. RT-PCR products of the partial exon1, completed exon2 and partial exon3 of the SLA classical I class 3 gene were successed to amplify in 32 WZSPs. According to genealogy and amplification results, PCR products of 16 WZSPs were selected to clone and sequence. 10 different nucleotide sequences were obtained. The sequences data and their coden amino acids sequences were compared with all sequences of SLAⅠ3 gene in GenBank, respectively. It was found that these sequences were different in comparison with each other or with those of published sequences of SLAⅠ3 gene, but there were very few variation among them. The data of comparing the amino acids sequences indicated that most of these sites are conserved among the related molecules between porcine and human. Meanwhile, construction of a phylogenetic tree using the nucleotide sequences of those 23 alleles and 1 HLA A gene indicated that WZSP population own its unique resource.
    Studies of KAP as candidate gene for economic traits in Cashmere Goats
    Scientia Agricultura Sinica. 2007, 40(9):  2062-2067 . 
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    Abstract: 【OBJECTIVE】 Liaoning cashmere goats’ genetic polymorphism of KAP gene was studied and the relationship between polymorphism loci and economic traits (cashmere trait and weight trait) was analyzed in order to find molecular marker of MAS, applying theory basis for next molecular breeding. 【METHOD】 The polymorphism of KAP gene was studied by PCR-SSCP. The least square mean(LSM),the least effect(LSE) and genetic variance of different genotype at 4 polymorphism loci were analyzed, the selection reaction was forecasted by genetic correlation between marker loci and genetic variance of economic traits. 【RESULTS】 In cashmere yield trait, LSM of AA and AB at S1 was significant difference (P<0.05) with BB genotype, BB at S2 was significant difference (P<0.05)with AA and AB genotype ,AA and AB at S3 was significant difference (P<0.05)with BB genotype, AB at S4 was significant difference (P<0.05)with AA and BB genotype; In weight trait , LSM of BB at S2 was significant difference (P<0.05)with AA and AB genotype, AA and AB at S3 was quite significant difference (P<0.01)with AA and AB genotype, BB at S2 was significant difference (P<0.05)with AB and AA genotype. 【CONCLUSION】S1-AB ,S1-BB,S3-BB and S4-AB was the favorable marker genotype for cashmere yield trait, S3-AA was the favorable marker genotype for weight trait, S2-BB was the marker genotype of cashmere yield trait and weight trait Keywords: Liaoning Cashmere goat, KAP, Economic traits
    Development and application of nested PCR assay for detection of dairy cattle-derived Cyclospora sp.
    Scientia Agricultura Sinica. 2007, 40(9):  2073-2078 . 
    Abstract ( 1223 )   PDF (509KB) ( 765 )   Save
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    Based on the cattle-derived Cyclospora sp. sequences, two pairs of primers were designed. These primers selectively amplified a 168-bp DNA fragment of the 18S rRNA gene of cattle-derived Cyclospora sp. With these primers, a nested PCR assay for detection of cattle-derived Cyclospora sp. was developed. The results showed that the nested PCR assay was specific and there is no cross-reaction with other parasites, such as Eimeria spp., Cryptosporidium spp., Giardia sp., Toxoplasma sp., Trichuris sp. and cattle ciliate. The assay was able to detect as low as 2.85×10-2 fg of control positive DNA. The results of detection of clinical samples revealed that the assay was coinciding with microscopic examination and it will be an effective tool for detection of Cyclospora sp. in cattle feces.
    Effect of Monochromatic Light on the concentration of LH and FSH in the serum of Laying Hens
    额尔敦木图 Erdemtu
    Scientia Agricultura Sinica. 2007, 40(9):  2079-2083 . 
    Abstract ( 1192 )   PDF (217KB) ( 1261 )   Save
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    【Objective】The concentration of LH and FSH in peripheral blood was studied by monochromatic light and to provide a scientific data about the mechanism action of monochromatic light effect on productive performance in laying hens. 【Method】Nineteen to 53 weeks old Laying hens were exposed to red, green and blue light from light emitting diode (LED) lamps and incandescent light in this study. All light sources were equalized under 15 lx light intensity for 16 h daily. 【Results】The results show: 1) The rise length of LH and FSH in blue light was longest and the peak value of LH and FSH in blue light was appeared at the last time from 25-34 wk. The LH in white light was highest and significantly higher than those in other light groups from 37-49 wk and the rise of LH in red light was persistent from 40-49 wk. 2) Within 24h, there is only one peak of LH and FSH concentration in W, B and R light treatments respectively, the peak value of LH concentration in W, B and R light treatments were reached at 10h, 07h and 10h. The peak values of FSH concentration in W, B and R light treatments were reached at 13h, 07h and 10h respectively. 3) There are three peak value of LH and FSH concentration in G light treatment, both peak values of which were simultaneously reached at 07h, 16h, and 01h respectively. 【Conclusion】The secreting of LH and FSH was enhanced by blue light from 19-36 wk and the secreting of LH and FSH was enhanced by white and red lights from 37-53 wk. The peak values of LH and FSH in All lights were appeared at morning within 24h (except FSH in white light).
    Expression and Purification of Goose’s HSP70 and Complex Formation with Virus Polypeptide
    Scientia Agricultura Sinica. 2007, 40(9):  2084-2090 . 
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    Abstract:【OBJECTIVE】 In order to study the specificity expression of HSP70 in heat shock, HSP70 purification and its characteristic of coalescent with antigen peptide to form the compound, we designed this experiment;【METHOD】 60 healthy, 6 weeks ages male Wulong geese were selected and stochastically divided into 3 groups, the geese in Control group didn’t pass through the heat treatment, while the treatment 1 group were shocked by 1 time 42±1℃, 5h acute heat treatment and then were slaughtered immediately, the treatment 2 group restored 12h after the heat treatment under the normal raising condition and then were slaughtered. Hearts were taken to make paraffin section for the immunization organizations chemical experiment and livers were used to purify HSP70. Geese hearts HSP70 expression differences in 3 groups were determined, at the same time experiments of HSP70 purification and appraisal in the liver was carried on. HSP70 purification and synthesis HBV PreS1 multi- peptides unified the compound, and was determined by the double special immune body ELISA. 【RESULTS】 The findings indicated that, widespread HSP70 masculine pellets in the cardic muscle were found in the hot shock condition, HSP70 expression in treatment group 1 centered in the karyotheca and its periphery, but treatment group 2 centered the emphasis in the cell membrane around; We could obtain the HSP70 purification through two sets of purification plans; the synthesis peptide and the HSP70 purification forms the compound under the certain condition, examination taken to compound formation with the double specificity immune body, and the examination result was masculine, which explained that the compound had formed. 【CONCLUSION】 HSP70 specificity expression in heat shock shifted by time, and it may suggest that HSP70 possibly do some certain functions in the cell protection; we can obtain high-purity HSP70 protein under the low pressure chromatographic analysis condition, and it was compared to be better the molecular sieve preliminary separation, ConA-agarose chromatographic analysis and the ADP-agarose chromatographically analyzes flow; Under in vitro certain condition, the man-power synthesizes the peptide to be possible to unify with HSP70 forms the compound, this for further proved the compound the immunity function provides the experimental foundation.
    Effects of Intensity-Stree on the Growth and Non-specific Immunity Factors of Litopenaeus vannamei
    Scientia Agricultura Sinica. 2007, 40(9):  2091-2096 . 
    Abstract ( 1490 )   PDF (351KB) ( 939 )   Save
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    Two culture systems were designed to classify the effects of intensity-stress and water quality factors on the growth of shrimp. In the first system, shrimps Litopenaeus vanname, were cultured at 150, 300, 600 and 900 individuals/m3. In the second system, shrimps were cultured with water drained from the first system. The growth, survival and non-specific immunity factors (PO、SOD、POD、Ua and Ul) of shrimp cultured in each system were determined. The results showed that weight gain, length gain and survival rate reduced with the increase of stocking intensity in the first system. Survival rate, weight and length gain, the activities of PO、POD、Ua and Ul of shrimp in the second system were higher than those of shrimp cultured in the first system, but SOD activity of shrimp in the first system was higher than that of the second system. There are no significant differences in water quality factors (TAN、NO2-N、NO3-N and PO4-P et al.) between the two systems, which suggested that the primary reason for the difference of shrimp growth and enzyme activities in the two systems was intensity-stree, while water quality only played a minor role.
    The Body Characteristic of Newly-Hatched Silkworm Bombyx mori and Its Applied Studies on Silkworm Eggs’ Hybrid Rate Test
    Scientia Agricultura Sinica. 2007, 40(9):  2097-2102 . 
    Abstract ( 1495 )   PDF (295KB) ( 766 )   Save
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    【Objective】The silkworm eggs’ hybrid rate test plays very important roles in the sericulture production ,while there is no ideal way to be broadly applied. 【Method】 Observed by anatomical microscope (anatomical lens), 【Result】The research find that the newly-hatched silkworm’s body characteristic such as bodily color, fleck, color and shape of fleck and bodily form is different from that of grown larval of 4th and 5th instar and distinct among different breeds. On the basis of that we invent a new way to identify the silkworm breed by the body characteristic of silkworm, Bombyx mori at the earlier larval stage. That is firstly establishing the body characteristic image and character data-base of every breed at the newly-hatched silkworm stage by anatomical microscope and photography equipment, and then comparing the body characteristic of the silkworm breed to be identified with the corresponding characteristic of every breed having known in the data-base, and making a statistic deduction on the inspectional results in the light of probability distribution theory and sample deduction method. In order to reduce the appraisal risk of mistaking unqualified silkworm breeds for qualified ones or in reverse mistaking qualified silkworm breeds for unqualified ones, we intend to adopt the way of secondary sample procedures. If the purebred number inspected out of the two samples which composed of 1000 individuals each is less than or equal to 38 and 79 respectively, then we judge the silkworm breed qualified one. 【Conclusion】We can achieve the aims of testing silkworm eggs’ hybrid rate easily and exactly and promptly with low cost at the early stage employing this method.
    RESEARCH NOTES
    Mapping of QTLs associated with leaf senescence in soybean
    Shiyou Cui
    Scientia Agricultura Sinica. 2007, 40(9):  2103-2108 . 
    Abstract ( 1458 )   PDF (366KB) ( 766 )   Save
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    【Objective】Leaf senescence is a character of plant development, Delayed leaf senescence or stay green character has received considerable attention because of its negative impact on photosynthesis and its role in nutrient redistribution within the plant. 【Method】RIL-1 and 2 populations were used identified QTLs associated with leaf senescence, and correlation between leaf senescence and yield traits were also conducted. 【Result】The primary results indicated that three QTLs for leaf senescence were detected and mapped on LG-C1, D1b+W and O, each QTL explained 5.8~13.7% of total variation. Leaf senescence significantly and positively correlated with biological yield, seed yield, plant height and days to maturity in both populations except lower correlation with days to maturity in RIL-2. However, different correlation between leaf senescence and harvest index were observed, negatively and significantly in RIL-1 and positively and significantly in RIL-2. 【Conclusion】These indicated that harvest index may be increased through the selection of delayed leaf senescence in soybean breeding, but breeding materials with high potential of yield couldn’t be obtained.
    1
    Scientia Agricultura Sinica. 2007, 40(9):  2109-2113 . 
    Abstract ( 1214 )   PDF (267KB) ( 1146 )   Save
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    Amplification, Cloning and Sequence Analysis of a repetitive 529bp DNA fragment from Toxoplasma gondii strains from China
    Scientia Agricultura Sinica. 2007, 40(9):  2114-2118 . 
    Abstract ( 1490 )   PDF (387KB) ( 1278 )   Save
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    Abstract: 【Objective】The objective of the present study was to examine sequence variation in the repetitive 529 bp DNA fragment among 9 T. gondii strains from different hosts and geographical locations in China, and to compare the sequences with that of the RH reference strain. 【Method】 The 529 bp fragment was amplified by PCR from genomic DNA of the 10 T. gondii strains, and the amplicons were purified, cloned into pGEM-T Easy vector and the recombinant plasmids were identified by colony PCR and digestion with endonuclease EcoR I, and then sequenced. 【Results】 Sequence variation in the repetitive 529 bp DNA fragment ranged between 0.8-2.9% among the 10 T. gondii strains, with sequence positions of 32-55 nucleotides being the most variable region. But the sequence variation was not related to virulence. 【Conclusion】The findings of the present study showed that the intraspecific variation in the repetitive DNA fragment was low and this repetitive DNA fragment provides an ideal genetic marker for the differentiation of T. gondii from other organisms, but it is not suitable for the studies of genetic variability within T. gondii.