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Table of Content

    15 January 2012, Volume 45 Issue 2
    CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    Genetic Dissection of Milestone Parent Aimengniu and Its Derivatives
    YU Hai-Xia, XIAO Jing, TIAN Ji-Chun
    Scientia Agricultura Sinica. 2012, 45(2):  199-207.  doi:10.3864/j.issn.0578-1752.2012.02.001
    Abstract ( 1056 )   PDF (573KB) ( 1006 )   Save
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    【Objective】 The objective of this study is to reveal the genetic structure of Aimengniu and the transmission of its specific loci in derivatives. 【Method】 A total of 836 DArT markers covering the whole genome of wheat were used to screen the three parents of Aimengniu, while 330 markers were effective for genetic contribution ratio. 【Result】 The results indicated that Neuzucht contributed more genetic components (52.2%) to their derivative than other parents (Aifeng3, 43.2% and Mengxian201, 35.4%). As for single chromosomes, Aifeng 3 had the contribution ratio of 12.2% (5D) -70.7% (2A), while 14.0% (1D) -68.3% (6D) for Mengxian201 and 21.5% (7A)-85.4% (5D) for Neuzucht. On the A, B and D subgenome levels, the values were 46.2%, 44.0% and 23.8% for Aifeng3. 34.9%, 35.9%, 42.7% for Mengxian201 and 44.4%, 51.8%, 52.0% for Neuzucht, respectively. Some markers with the higher contribution ratio and inheritable rates were also detected.【Conclusion】These markers were in accordance with important genes and QTLs located on these genomic regions, this may useful for marker/trait association studies. 
    RFLP Analysis of Mitochondrial Genomes Between Cytoplasmic Male Sterile Line and Maintainer Line in Upland Cotton
    ZHANG Xiao, ZHANG Rui, SHI Ji, MENG Zhi-Gang, SUN Guo-Qing, ZHOU Tao, GUO San-Dui
    Scientia Agricultura Sinica. 2012, 45(2):  208-217.  doi:10.3864/j.issn.0578-1752.2012.02.002
    Abstract ( 817 )   PDF (835KB) ( 658 )   Save
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    【Objective】 Identification of the differences of mitochondrial genomes between cytoplasmic male sterile (CMS) line and maintainer line of cotton could make a foundation for cloning CMS-associated gene in cotton.【Method】In this study, 20 mitochondrial gene probes, atpA, atp6, atp9, ccmB, ccmC, ccmFN1, cob, coxI, coxII, coxIII, matR, nad1bc, nad2, nad4, nad5, nad6, nad7c, nad9, rpl5, and rrn18, were used to identify the differences between the P30B normal fertile (N-) and the P30A male sterile (S-) cytoplasm with Southern blot method.【Result】Among the 20 genes, atpA, atp9, ccmB, nad1bc, nad6, nad7c and rrn18 revealed restriction fragment length polymorphisms (RFLPs) between N- and S-cytoplasm. The differences in atpA locus were most obvious.【Conclusion】 atpA was an important mitochondrial genomic site that showed an obvious difference between CMS line and maintainer line of cotton. One rrn18 gene copy was deleted in the mitochondrial genome of CMS line.
    TILLAGE & CULTIVATION·PHYSIOLOGY & BIOCHEMISTRY·AGRICULTURE INFORMATION TECHNOLOGY
    Climatic Suitability of Double Rice Planting Regions in China
    DUAN Ju-Qi, ZHOU Guang-Sheng
    Scientia Agricultura Sinica. 2012, 45(2):  218-227.  doi:10.3864/j.issn.0578-1752.2012.02.003
    Abstract ( 1179 )   PDF (850KB) ( 1227 )   Save
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    【Objective】 The objectives of this study are to clarify major climate factors affecting the distribution of double rice planting regions in China based on national and annual scales, and to give the distribution of double rice planting regions and their climate suitability divisions, in order to provide a scientific basis for optimizing double rice allocation of production, modifying cropping pattern and ensuring food security. 【Method】 In terms of potential climate factors selected from the related literatures based on national and annual scales, double rice geographic information from national agrometeorological observation stations of China Meteorological Administration (CMA), together with the maximum entropy model (MaxEnt) and the spatial analysis function of ArcGIS software, major climate factors affecting the distribution of double rice planting regions in China were clarified, and the relationship between the distribution of double rice planting regions and climate were discussed. 【Result】 The results show that annual precipitation (P), mean temperature of the warmest month (TW) and days of not less than 18℃ stably (N18) are dominant climate factors affecting the distribution of double rice planting regions in China, contributing 99.1% of all the potential climate factors. The distribution of double rice planting regions in China is simulated well in terms of the maximum entropy model and the selected dominant climate factors. The suitable land area for planting double rice in China is 1.74 million km2, and it is more than the practical cultivated area (60 105 km2). Furthermore, the climatic suitability divisions of double rice planting regions in China are given based on its appearance frequency. The climate characteristics of double rice in each climatic suitability region are analysed, respectively.【Conclusion】The relationship between the distribution of double rice planting regions and climate based on the maximum entropy model is able to reveal the distribution of double rice planting regions and its climatic suitability divisions in China. The results indicate that double rice could be largely developed in China due to its huge climate suitable planting regions. The results can provide reference for double rice planting pattern and countermeasures to cope with climate change in China.
    Analysis of the Temporal and Spatial Changes of Photo-thermal Resources in Winter Wheat Growing Regions in China
    WANG Bin, GU Yun-Qian, LIU Xue, LUO Wei-Hong, DAI Jian-Feng, ZHANG Wei, QI Chun-Jie
    Scientia Agricultura Sinica. 2012, 45(2):  228-238.  doi:10.3864/j.issn.0578-1752.2012.02.004
    Abstract ( 869 )   PDF (1523KB) ( 1094 )   Save
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    【Objective】To identify the temporal and spatial changes of photo-thermal resources during the growing season and key development stages of winter wheat in China so as to mitigate the impacts of climate change on wheat production in China by adjusting cropping system and crop distribution according to changing trends of photo-thermal resources.【Method】Daily data of temperature and sunshine hours of 47 years (1961-2007) from 264 meteorological stations in the winter wheat growing regions in China were used to calculate daily active temperature (>0℃) and daily total global radiation. The theoretical dates when winter wheat reaches its main development stages were determined based on the accumulated active temperature required by each development stage. Photo-thermal resources (the growth degree days (GDD), the thermal time (TT), the total global radiation, and the product of thermal effectiveness and global radiation (TEP)) for the whole growing season and the key development stages were then calculated. The grid data were obtained by means of inverse distance weight spatial interpolation using ArcGIS (v9.3).【Result】During the 1961-2007, the theoretical sowing date of winter wheat delayed averagely by 0.5 d•10a-1, that of heading and ripening became earlier averagely by 1.6 d•10a-1 and 1.7 d•10a-1, respectively, and the whole growing season was shortened averagely by 2.2 d•10a-1. During winter wheat growing season, the GDD and the total TT increased averagely by 7.8℃•d•10a-1 and 0.6 d•10a-1, respectively, the total global radiation decreased averagely by 39.69 MJ•m-2•10a-1 (by -2.34%•10a-1), and the TEP decreased averagely by 10.18 MJ•m-2•10a-1 (by -1.22%•10a-1). From sowing to heading, the GDD and the total TT increased averagely by 6.2 ℃•d•10a-1 and 0.57 d•10a-1, respectively, the total global radiation decreased averagely by 27.7 MJ•m-2•10a-1 (by -2.72%•10a-1), and the TEP decreased averagely by 5.2 MJ•m-2•10a-1 (by -1.18%•10a-1). From heading to ripening, the GDD and the total TT increased averagely by 1.6 ℃•d•10a-1 and 0.05 d•10a-1, respectively, the total global radiation decreased averagely by 12 MJ•m-2•10a-1 (by -1.78%•10a-1), and the TEP decreased averagely by 4.97 MJ•m-2•10a-1 (by -1.26%•10a-1).【Conclusion】During the 1961-2007, in the North region and in Mid-eastern Shandong Province of Huang-Huai region for winter wheat growing, the decreases of both TEP and the length of wheat growing season indicate that changes in photo-thermal resources had negative effects on winter wheat potential productivity in these regions. In the rest regions (the Southwest, the Middle and Lower Reaches of the Yangtze River, the Huang-Huai, and the South) for winter wheat growing, the increased TEP had a positive impact on winter wheat potential productivity whereas the shortened growing season had a negative impact on winter wheat potential productivity, hence, the impacts of changes in photo-thermal resources on winter wheat potential productivity is positive or negative can only be determined by resorting to quantitative analysis using crop growth simulation models.
    PLANT PROTECTION
    Control Effect and Action Mechanism Research of Bio-Organic Fertilizer on Eggplant Bacterial Wilt
    DING Chuan-Yu, QIAO Huan-Ying, SHEN Qi-Rong, RAN Wei, CHEN Wei
    Scientia Agricultura Sinica. 2012, 45(2):  239-245.  doi:10.3864/j.issn.0578-1752.2012.02.005
    Abstract ( 1086 )   PDF (521KB) ( 1000 )   Save
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    【Objective】The objective of this study is to research the effect of bio-organic fertilizer BIO-36 and BIO-23 on eggplant bacterial wilt, enzyme activities and rhizosphere soil microbial. 【Method】 The organic fertilizer (pig manure compost and amino acid fertilizer) were innoculated with Bacillus subtilis strain II-36 and I-23 for a second solid fermentation to produce the specific bio-organic fertilizer BIO-36 and BIO-23. A pot experiment was used to identify the control effect. 【Result】 The bio-organic fertilizer inhibited the eggplant wilt disease (antagonistic effect, respectively, 96% and 91%). The activities of antioxidases (catalase, peroxidase and superoxide dismutase) in eggplant leaves were significantly higher, but the content of MDA was reduced remarkably. CAT activities for BIO-36 and BIO-23 increased by 25.0% and 23.7% respectively as compared with the control, the activities of POD increased by 99.5% and 93.6% and that of SOD increased by 32.7% and 29.8%, respectively, while the contents of MDA decreased by respectively 29.5% and 26.3%, respectively comparing with control. In addition, the application of bio-organic fertilizer changed microbial communities in rhizosphere soil significantly decreased the number of Ralstonia solanacearum, increased fungi and actinomycetes, smaller changes in bacteria. 【Conclusion】 The specific bio-organic fertilizer against eggplant bacterial had some connection with induction of systemic resistance of plant and regulation of rhizosphere microbial diversity.
    Effects of the Introduction of Biocontrol Agent Trichoderma harzianum T4 on the Bacterial Community in Cucumber Rhizosphere
    YIN Dan-Han, GAO Guan-Peng, XIA Fei, WANG Wei
    Scientia Agricultura Sinica. 2012, 45(2):  246-`254.  doi:10.3864/j.issn.0578-1752.2012.02.006
    Abstract ( 740 )   PDF (643KB) ( 1062 )   Save
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    【Objective】The objective of this study is to analysis the impact of T. harzianum T4 introduction on the indigenous bacterial community of rhizosphere soil, and to provide objective biosafety evaluations for the field application of biocontrol agents. 【Method】 Comprised molecular tools DGGE and T-RFLP were used in this study to assess the modifications of the bacterial community in cucumber rhizosphere after inoculation with T. harzianum T4. 【Result】 Introduction of T. harzianum T4 in the soil resulted in significant variations of the bacterial community structures from 14 to 56 days post-inoculation. During this period the impact of T4 was sustainable and weakened gradually. T. harzianum T4 could restrain effectively Cyanobacterium, Beta-proteobacterium, Staphylococcus, Burkholderia, Serratia, Acidobacterium and some kinds of soil uncultured bacterium, while it improved the growth of Bacillus, Agrobacterium and Gemmatimonadetes observably. On 70th day after T. harzianum T4 introduced, as 2 weeks after harvest, there was no prominent alteration of bacterial community due to inoculation with T4. 【Conclusion】 Tracking of the modifications of the indigenous bacterial community by 16S rDNA DGGE and T-RFLP analysis not only described comprehensively the variations of the structure of soil bacterial community, but also showed the preliminary and qualitative information of bacterial community change. In general, the application of T. harzianum T4 exerted only transient impact on the bacterial community of cucumber rhizosphere in systematic field investigation, but the perturbation was unable to imperil the bacterial community stability in the long-term.
    Resistance of Different Tea Cultivars to Empoasca vitis Göthe
    JIN Shan, SUN Xiao-Ling, CHEN Zong-Mao, XIAO Bin
    Scientia Agricultura Sinica. 2012, 45(2):  255-265.  doi:10.3864/j.issn.0578-1752.2012.02.007
    Abstract ( 1174 )   PDF (672KB) ( 1211 )   Save
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    【Objective】 The objective of this study is to analyze resistant levels of 9 tea cultivars to small green leafhopper (SGL) Empoasca vitis and to establish foundation for mechanism research in the resistance of various tea cultivars. 【Method】 The population dynamics in tea garden, life cycle, number of laid nymphae per female and nymph survival rate of SGL on different tea cultivars were investigated. Moreover, the feeding behavior of SGL on tea cultivars were obtained by using electrical penetration graph (EPG) technique. 【Result】 (1) The population density on Enbiao (EB), Zhushanyihao (ZS), Banzhuyuan (BZY) and Lantian (LT) cultivars were more than Deqing (DQ), Jiande (JD), Changxingzisun (CX) and Juyan (JY). (2) The life cycle duration on DQ, JY, CX, JD and Longjing 43 (LJ) were significantly longer than that on EB, BZY and ZS. (3) The number of laid nymphae per female on EB and BZY were significantly more than that on JY, CX, JD and LJ. (4) The difference existed in nymph survival rate on various cultivars. The survival rate of nymphae on EB and ZS were the highest, amounted 55.00% and 50.00% respectively, while the lowest was on JY, amount 32.00%. (5) The total feeding duration on ZS and EB were significantly longer than that on DQ, JY, CX, JD and LJ. (6) The resistant levels of the 9 tea cultivars to SGL were classified into two groups based on the result of cluster analysis according to the life cycle duration, number of laid nymphae per female, nymph survival rate and the feeding duration. The first group, including JY, DQ, LJ, JD and CX, was resistant to the SGL, and the second group was susceptible to the SGL, consisting of LT, BZY, ZS and EB. Generally, the order of resistance level with 9 cultivars from strong to weak were JY > DQ, LJ, JD and CX > LT, BZY and ZS > EB. 【Conclusion】 The natural choice, adaptability and feeding preference of SGL on various cultivars are reflected well based on the dynamics of population density, life cycle, number of laid nymphae per female, nymph survival rate and feeding duration, which are significantly different in the classification of various cultivars in resistant levels to the SGL.
    SOIL & FERTILIZER·WATER-SAVING IRRIGATION·AGROECOLOGY & ENVIRONMENT
    Response of the Turnover of Soil Organic Carbon to the Soil Moisture in Paddy and Upland Soil
    WANG Ai-Hua, SU Yi-Rong, LI Yang, HU Le-Ning, WU Jin-Shui
    Scientia Agricultura Sinica. 2012, 45(2):  266-274.  doi:10.3864/j.issn.0578-1752.2012.02.008
    Abstract ( 972 )   PDF (568KB) ( 867 )   Save
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    【Objective】To ascertain the difference of the accumulation of soil organic carbon (SOC) in paddy and upland soil, the mineralization, dissolved organic carbon (DOC) and microbial biomass carbon (MBC) in soil under different soil moisture conditions were determined. 【Method】 In laboratory, one portion of paddy and upland soil was incubated under 45%, 60%, 75%, 90% and 105% water holding capacity (WHC) to measure the mineralization of SOC. The other portion was incubated under 45%, 75% and 105%WHC to measure the DOC and MBC content in soil. All the soils were placed at 25℃,100% air humidity for 100 days.【Result】The soil moisture, land use (paddy and upland) and the interactions of them all had significant effects on the mineralization of SOC, content of soil DOC and MBC. The accumulative mineralized proportion (amount) of SOC increased as moisture content increased from 45% to 90%WHC in paddy soil and from 45% to 75%WHC in upland soil. Meanwhile, the half decay time of SOC (paddy, 5.23-7.57 age; upland, 6.79-12.87 age) decreased as moisture content increased. During 100 d incubation period, the equivalent of 2.33%-3.94% and 1.66%-3.33% of SOC in paddy and upland soil respectively, were mineralized. Both the mineralization rate of SOC in paddy and upland soil were greater under flooding condition than under aerobic condition. However, the content of DOC and MBC in paddy soil were lower under flooding condition.【Conclusion】Along with the increasing of soil moisture content, from 45%-90%WHC in paddy soil and from 45%-75%WHC in upland soil, the mineralization of SOC will be accelerated, thereby the soil nutrient release will be expedited. Nevertheless, the increase in soil moisture has no positive-effects on the DOC and MBC content of soil. The reasons, why the mineralization rate and the accumulative mineralization proportion (amount) of SOC were higher under flooding condition or in paddy soil than under aerobic condition or in upland soil, may be that the decomposition of SOC be accelerated by the alternation of drying and wetting of soil, and the priming effects of the alternation of drying and wetting on the paddy soil are greater than that on the upland soil.
    Soil Microbial Biomass N Turnover After Long-Term Fertilization in Paddy Field
    LU Mei-Rong , LI Zhong-Pei, LIU Ming, JIANG Chun-Yu, CHE Yu-Ping
    Scientia Agricultura Sinica. 2012, 45(2):  275-282.  doi:10.3864/j.issn.0578-1752.2012.02.009
    Abstract ( 1033 )   PDF (498KB) ( 854 )   Save
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    【Objective】Soil microbial biomass plays an important role as a dynamic sink of nutrients. Soil microbial biomass turnover was evaluated after long-term fertilizer application to understand the influence of fertilization on nutrients cycling and nutrients available for plant uptake.【Method】Using soil samples taken from long-term fertilization field of N, P, K fertilizers, organic manure cycling or half amount of rice straw, soil microbial biomass, microbial biomass turnover and grain yield of rice (Oriza sativa L.) under fertilization were determined. 【Result】P fertilizer application increased soil microbial biomass N and C, microbial biomass N turnover and grain yield by 13.2%, 33.1%, 31.2% and 173.4% averagely compared to P fertilizer-omitted treatments. Organic manure application only increased soil microbial biomass N and C, and grain yield by 36.1%, 28.1% and 68.1% , and decreased soil microbial biomass N turnover by 4.3% averagely compared to CK. Incorporation of inorganic and organic fertilizer increased soil microbial biomass N and C, microbial biomass N turnover and grain yield, NPKC and NPKS treatments increased respectively by 40.1%, 26.3%, 177.1%, 204.1% and 36.1%, 20.9%, 192.9%, 203.3% compared to CK.【Conclusion】Incorporation of inorganic and organic fertilizers increased soil available nutrients sink, soil nutrients cycling and nutrients available for plant uptake to high soil productivity.
    Slow Release Characteristics of the Low Molecular Weight Polylactic Acid- Coated Urea and Its Reduction Effects on Soil Ammonia Volatilization
    LU Jing , LI Dan, SUN Jian-Bing, NI Wu-Zhong
    Scientia Agricultura Sinica. 2012, 45(2):  283-291.  doi:10.3864/j.issn.0578-1752.2012.02.010
    Abstract ( 911 )   PDF (880KB) ( 858 )   Save
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    【Objective】 This paper presented an approach for preparing low molecular weight polylactic acid (PLA)- coated slow-release urea. The release behavior and reduction of ammonia volatilization after the coated urea added into soil were studied. 【Method】 By spouted-spraying methods, film coated urea fertilizers were prepared with two types of low molecular weight PLA (relative molecular weight-RMW5 000 and RMW10 000) respectively, retreated with paraffin wax as sealant or not, thus four types of coated urea were obtained. The structure of coating film was observed by scanning electronic microscopy (SEM), nitrogen release was investigated by a soil column leaching method, and ammonia volatilization was determined with an incubation experiment. 【Result】 SEM images showed that both of RMW5 000 and RMW10 000 PLA as a film coated on the surface of granular urea. Paraffin wax used as a sealant could fill up the micro holes or cracks in the coating film. Under the same nitrogen dose added, the amounts of total nitrogen leaching from soil column of the treatments with coated urea were significantly lower than that of the normal urea treatment, implying that the slow-release effectiveness of coated urea is clear. In the incubation experiment, it was found that nitrogen losses through ammonia volatilization of the treatments with coated urea were significantly lower than that of the urea treatment. 【Conclusion】 Low molecular weight PLA coated urea is a new environment-friendly type of slow-release fertilizer, and its application in sustainable agriculture is prospective.
    Soil Fauna Diversity in the Rotational Grazing Pasture in Subalpine Meadow
    XIAO Hong-Yan, LIU Hong, LI Bo, YUAN Xing-Zhong, SUN Shu-Cun, CHEN Zhong-Li
    Scientia Agricultura Sinica. 2012, 45(2):  292-301.  doi:10.3864/j.issn.0578-1752.2012.02.011
    Abstract ( 796 )   PDF (702KB) ( 680 )   Save
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    【Objective】 The objective of this study is to understand the community characteristics of soil faunal in rotational grazing pasture in subalpine meadow of Tibetan Plateau.【Method】An investigation was made on the soil faunal communities under different grazing time (winter pasture, WP and summer pasture, SP) from May to October 2008 in subalpine meadow of north-west in Sichuan. The methods of Baermann, Tullgren and hand-picking were used to separate soil animals from soil samples (0-15 cm).【Result】A total of 46 746 individuals were collected, belonging to 6 phyla, 9 classes, 16 orders and 61 groups, in which 22 092 individuals belonging to 6 phyla, 9 classes, 15 orders and 42 groups were colleted from WP, while 24 654 individuals were colleted from SP which belonged to 6 phyla, 9 classes, 15 orders and 46 groups. And Nematoda was dominated group both in SP and WP. The soil animal communities under different grazing time had different number changing tendencies and varied with the seasons, both in individual numbers and communities. The numbers of individuals of the soil fauna were SP>WP in spring, WP>SP in summer and autumn and the group number were SP>WP in spring and autumn, WP>SP in summer. The individual densities and group numbers in different depths had their variation in seasons. Both the densities and group numbers in SP were diminishing with depth in three observation seasons. The group numbers of soil fauna decreased obviously with increasing soil depth in all three seasons while from spring to autumn, the individual densities changed from diminishing with depth to increasing with depth. In spring all of diversity indices of WP were higher than those of SP and showed no significant difference. In summer the Margalef index and Simpson index of WP were higher than those of SP, while Shannon-Wiener index and Pielou index of WP were lower than those of SP and Simpson index, Shannon-Wiener index and Pielou index showed significant difference between WP and SP. In autumn, the Simpson index of WP was significantly higher than that of SP while other diversity indexes were lower than those of SP, and Shannon-Wiener index and Pielou index in WP were significantly lower than those of SP. 【Conclusion】Compared with other regions, the soil animal community composition in the subalpine meadow of the eastern Tibetan Plateau was simpler, while the density was higher. Rotational grazing had a significant influence on seasonal dynamics of soil fauna, while the composition of soil animals in two habitats was similar.
    HORTICULTURE
    Cloning and Sequence Analysis of the Aquaporins Gene SlAQP in Tomato
    LI Ren, WU Xin-Xin, LI Wei, YANG Rong-Chao, ZHAO Yong-Qin, WEN Chang-Long, ZHAO Bing, GUO Yang-Dong
    Scientia Agricultura Sinica. 2012, 45(2):  302-310.  doi:10.3864/j.issn.0578-1752.2012.02.012
    Abstract ( 755 )   PDF (831KB) ( 1326 )   Save
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    【Objective】 To provide basal data for mechanism of tomato’s drought resistance and cultivar development, the sequence characteristics of the aquaporin gene SlAQP in tomato were analyzed, the coded protein was intracellar located and the expression profiling of the Mirco Tom tomato was studied after treatment under drought stress. 【Method】 The rapid-amplification of cDNA ends (RACE) was used to amplify the full-length SlAQP gene, and the bioinformatics software was used to analyze the structures and function of the coded protein. In order to follow the intracellular localisation of the protein, the GFP sequence was fused downstream to the SlAQP coding region and the fusion gene SlAQP::GFP transferred into onion epidermal cells by biolistic method. The Mirco Tom tomato was used as material, the real time-PCR was adopted to study the expression profile of gene SlAQP.【Result】 The full-length cDNA of SlAQP gene (GenBank Accessin No. HQ433337) consists of 1 107 bp and contains a 852 bp open reading frame(ORF) encoding 283 amino acid proteins. Bioinformatics analysis demonstrated that SlAQP gene exhibited a typical structure with six membrane-spanning domains and an internal symmetry showing two highly conserved Asn-Pro-Ala (NPA) motifs, and possessing the MIP family signal consensus sequence. The SlAQP amino acids showed high identity with other 10 plant species PIP subfamily by NCBI homology comparison analysis. Phylogenetic analysis among 11 species indicated that SlAQP was clustered with the StAQP from Solanum tuberosum. The result of transient expression showed that SlAQP gene was located in the membrane. Southern blot analysis indicated that SlAQP was a single-copy gene. Real time-PCR analysis showed that the expression of SlAQP gene was down-regulated by drought stress.【Conclusion】The expression profiling of this gene indicates that the SlAQP gene may regulared by drought stress. This paper provides important information for the future study on the gene-expression regulation during drought stress.
    Genetic Association of Fruit Weight and Six Phenological Traits in Peach (Prunus persica L.)
    CAO Ke, WANG Li-Rong, ZHU Geng-Rui, FANG Wei-Chao, CHEN Chang-Wen, ZHAO Juan
    Scientia Agricultura Sinica. 2012, 45(2):  311-319.  doi:10.3864/j.issn.0578-1752.2012.02.013
    Abstract ( 768 )   PDF (1018KB) ( 1047 )   Save
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    【Objective】 Association mapping is an effective approach for identifying quantitative trait loci (QTLs) and may be an alternative to QTL mapping based on crosses between different lines. The study aims to improve the speed and efficiency of fruit quality breeding by investigating the genetic correlation of fruit weight and six phenological traits in peach (Prunus persica) using association mapping approach. 【Method】 In the current study, 104 peach landrace accessions from 6 Chinese geographical regions were evaluated for fruit and phenological period traits. The accessions were genotyped with 53 genome-wide simple sequence repeats (SSR) markers. The population structure and linkage disequilibrium (LD) of peach were analyzed by using STRUCTURE 2.3.3 and TASSEL 2.0.1 software. The genetic correlation was studied based on the results of association mapping of fruit weight and six phenological traits. 【Result】 Based on population structure analysis, the 104 peaches were divided into 5 groups. Of the 1378 SSR pairs composed of 53 SSR primers, 27 were in LD (P<0.01). Although correlation analysis showed that the fruit weight was only related to leaf expansion date trait positively, same QTLs were found associated with fruit weight and the date of full bloom, leaf expansion, harvest maturity, and defoliation based association mapping. Simultaneously, the obviously LD was observed among the interchromosomal loci association with fruit weight and the date of full bloom, defoliation and fruit development period. UDP96-013-206, an allele which possesses a significantly positive effect on fruit weight also acted on the phenological trait to advance the bloom date for 1.46 days, delay the fruit development period and defoliation date for 13.77 and 2.17 days, respectively. 【Conclusion】 Twenty-seven QTLs associated with fruit weight and six phenological traits were obtained using association mapping, and many of them were located in same chromosomes which obtained using linkage analysis previously. Although fruit weight was only related to leaf expansion date through correlation analysis, the real genetic correlation was found between fruit weight and the date of full bloom, leaf expansion, harvest maturity, defoliation, and fruit development period. Pleiotropy or close linkage are the two major reasons for genetic correlation in these correlated traits.
    Polymorphism of DFR Gene Intron 2 and Intron 3 in Sweet Cherry
    WANG Nian, YAN Jin-Hui, ZHANG Kai-Chun, WANG Jing, ZHANG Xiao-Ming, YAN Guo-Hua
    Scientia Agricultura Sinica. 2012, 45(2):  320-329.  doi:10.3864/j.issn.0578-1752.2012.02.014
    Abstract ( 724 )   PDF (736KB) ( 1049 )   Save
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    【Objective】 The relationship between polymorphism of DFR gene and pericarp colors was studied in 70 sweet cherry varieties. 【Method】 DNA sequences analysis was applied to detect the polymorphism of DFR gene in 10 sweet cherry varieties (Prunus avium L.) of different colors in pericarp. Special primers were designed to amplify the polymorphic DNA fragments. 70 sweet cherry varieties  (P. avium L.) were used to test DFR gene polymorphism. 【Result】 The DNA sequences of partial DFR gene about 1 kb were obtained from sweet cherry (P. avium). The identity of these DNA sequences was 80% with DFR gene of peach (Prunus persica). The identity of predicted amino acid sequences was 99% with the amino acid sequence of DFR in sweet cherry. This partial DFR gene contained 3 extrons and 3 introns. Two polymorphic loci were detected in intron 2 and intron 3. Three haplotypes and five haplotype combinations were found among 70 sweet cherry varieties which are composed of yellow pericarp group, yellow with a pink blush pericarp group and red pericarp group. There was no significant difference in the DFR gene frequencies between yellow with a pink blush pericarp group and dark red pericarp group. 【Conclusion】 Two polymorphism    loci were detected in intron 2 and intron 3 of DFR gene. Preponderatn alleles frequencies of 70 sweet cherry varieties was 0.864 in intron 2 and  0.679 in intron 3,respectively. There is no direct relationship between pericarp colors and polymorphisms DFR gene in intron 2 and intron 3.
    STORAGE·FRESH-KEEPING·PROCESSING
    Screening and Identification of Single-Chain Antibodies Against Microcystin-LR by Magnetic Beads and Time Resolved Fluorescence Immunoassay
    LIU Yuan, Huovinen Tuomas, LIU Xian-Jin, LIANG Ying, ZHANG Cun-Zheng, XIE Ya-Jing, HE Jiang, WANG Yun, ZHANG Xiao
    Scientia Agricultura Sinica. 2012, 45(2):  330-337.  doi:10.3864/j.issn.0578-1752.2012.02.015
    Abstract ( 628 )   PDF (677KB) ( 1000 )   Save
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    【Objective】 Single chain antibodies (scFv) against microcystin-LR were rapidly isolated from a synthetic mouse phage display library. 【Method】 Two rounds of binding were designed by using magnetic beads and subtractive panning. After each round of binding, the ratio of out to input of phage and polyclonal phage immunoassay were employed to investigate the enrichment of specific phage. The scFv genes after the second round of binding were extracted and cloned into the soluble expression vector. The soluble format of scFv was induced by IPTG and determined by time resolved fluorescence immunoassay, and then the positive clones were sequenced. 【Result】 The ratio of out to input of phage after two rounds of binding were 4.8 × 10-8 and 2.88 × 10-6, respectively. In polyclonal phage immunoassay, the signal to background ratio for the library after the second round of binding increased by 22.8 fold to the primary library. Finally, 5 unique positive clones were isolated from the libraries, and the detection limit (IC10) and IC50 for the best clone was 13 ng•mL-1and 435 ng•mL-1, respectively. The linear range for microcystins-LR detection was between 31-5 952 ng•mL-1. 【Conclusion】 In this study, these isolated single-chain antibodies were potentially used in the immunological detection for microcystin LR or preparation of immunoaffinity columns. Meanwhile, an efficient screening and identification methods of scFv against microcystin-LR was also explored.
    Microbial Community Diversity Analysis During the Pickled Processing of Mustard Tuber with Low-Salinity
    WENG Pei-Fang, CHEN Xi, SHEN Xi-Quan, WU Zu-Fang, REN Jing
    Scientia Agricultura Sinica. 2012, 45(2):  338-345.  doi:10.3864/j.issn.0578-1752.2012.02.016
    Abstract ( 873 )   PDF (548KB) ( 883 )   Save
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    【Objective】 Microbial community structure, population changes of microorganism and the quality characters of pickled vegetables were investigated, respectively, in order to elucidate the predominant microorganisms involved in pickled processing of mustard tuber under the condition of low salt concentration.【Method】 By means of 16S rDNA clone library and clone units analysis, the microbial diversity, predominant community and its changes were conducted during different fermentation phases at 5% and 7% salinity of pickled mustard tuber.【Result】 The results showed that Lactobacillus, Leuconostoc and Weissella were the predominant community at the early stage of the 5% salt concentration system, but the dominant microorganism at 7% system was Weissella hellenica. At the late phase of pickled processing, Lactobacillus plantarum played a leading role in the pickled system of mustard tuber. In addition, the pH change descended quickly at the 5% salt concentration, reached the lowest value of 3.79 within 10 days, but it reached 4.49 at 7% salt concentration within 20 days. In contrast, the population of lactic acid bacteria increased rapidly at lower salinity, which reached the 3.22×108CFU/mL at the 10th day, the total population of lactic acid bacteria was the 100 times lower compared to that of 7% salinity. The content of nitrate and nitrite in pickled product of three month preservation reached 320 mg•kg-1 and 2.9 mg•kg-1, respectively. 【Conclusion】 Microbial diversity of pickled mustard tuber could be investigated by 16S rDNA clone library method. The pH value always descends until a stable level between 3.9 and 4.0. Low salt concentration is benefitical to the growth of lactic acid bacteria and the predominant species are Lactobacillus, Leuconostoc and Weissella at the early phase under the 5% salinity pickling. But the main species become Weissella hellenica at 7% salinity. The crucial microorganism is Lactobacillus plantarum in the stable periods of pickling. The content of nitrate and nitrite in pickled product is greatly lower compared with the traditional processing of pickled mustard tuber. No significant difference of other components occurred between them.
    ANIMAL SCIENCE·RESOURCE INSECT
    Establishment of Aortic Endothelial Cells Model in Vitro from Wuzhishan of Inbred Miniature Pig and Expression of  In?ammatory Cytokines Mediated by TLR2
    WANG Pan, TAO Xiao-Li, SHEN Zu-Nan, LI He-Gang, PAN Jie, MOU Yu-Lian, LI Kui
    Scientia Agricultura Sinica. 2012, 45(2):  346-352.  doi:10.3864/j.issn.0578-1752.2012.02.017
    Abstract ( 645 )   PDF (450KB) ( 641 )   Save
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    【Objective】 This study aimed to explore a protocol of isolation, culture and identification of Wuzhishan Inbred Miniature Pig aortic endothelial cells (EC), and to study the regulation of Toll-like receptor 2 (TLR2) expression by LPS in EC with the expression of in?ammatory cytokines mediated by TLR2.【Method】Thoracoabdominal aortic were isolated from 3-4 month-old Wuzhishan Inbred Miniature Pig, disassociated with 0.1% collagenase I. Aortic EC were identified with the methods of uptake of fluorescence-labeled acetylated low density lipoproteins (DiI-Ac-LDL) and detecting of CD31 expression in the cells by flow cytometry. After stimulation of aortic derived EC with 1 μg•mL-1 lipopolysaccharide (LPS) for 0, 6, 8 and 12 h, the level of TLR2 and TLR4 mRNA was detected by real-time PCR. Furthermore, we detected the influence of lipoteichoic acid (LTA) on IL-6, IL-8 and ICAM-1 expression in aortic EC pretreated for 12 h with 1 μg•mL-1 LPS. 【Result】 Obtained Wuzhishan Inbred Miniature Pig aortic EC displayed paving stone-like pattern with high vitality. The cultured cells expressed CD31 and Ac-LDL Receptor in membrane, demonstrating that they were indeed EC. Stimulation of aortic derived EC with LPS induced a strong increase in TLR2 mRNA but not in TLR4 mRNA. LTA potentiated the increase of the in?ammatory cytokines IL-6, IL-8 and ICAM-1 expression in EC pretreated with LPS, but not in EC without LTA. 【Conclusion】The present study successfully isolated and identified Wuzhishan Inbred Miniature Pig aortic EC in vitro culture system. LPS stimuli induced a high TLR2 expression in EC, which mediated the expression of inflammatory cyokines.
    cDNA-AFLP Analysis on Transcripts Associated Gene with Broodiness in Muscovy Duck
    WU Xu, YAN Mei-Jiao, LIU Li-Ping, FU Xing-Yuan, LIAN Sen-Yang, LI Ang
    Scientia Agricultura Sinica. 2012, 45(2):  353-358.  doi:10.3864/j.issn.0578-1752.2012.02.018
    Abstract ( 973 )   PDF (455KB) ( 698 )   Save
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    【Objective】 The objective of this experiment is to identify differentially expressed genes of Muscovy Duck broodiness. 【Method】cDNA-AFLP approach was employed to analyze genes differentially expressed in broodiness and non-broodiness Muscovy Duck individuals derived from a single RF white feathers line. 【Result】 There were 82 differentially expressed bands associated with broodiness behaviors, 15 bands of them were subject to sequence analysis. Database searches indicate that 8 cDNA fragments show high homology to known genes, which include some function genes in hypothalamic- pituitary-gonadal axis regulating reproduction, such as GnRH gene and FSH gene. Meanwhile genes were also found in GH-IGF axis, such as GH gene. Other genes participated in signal transduction, transcription, metabolism biological processes, such as superoxide dismutase, keratin related protein, thiocyanate enzyme release S-transferase enzymes etc. Two cDNA fragments show homology to unknown function genes, 5 cDNA fragments show no detectable homology to know genes, suggesting that they probably represent novel genes. Three bands selected randomly from them were confirmed by RT-PCR and that result was consistent with the results of cDNA-AFLP. 【Conclusion】 The results of this paper uncovered the regulation mode of gene express variation of different Muscovy Duck broodiness traits, and thus further providing the molecular mechanism of broodiness of Muscovy Duck.
    Construction of Knock-Out Vectors for Bovine MSTN
    ZHAO Li-Hua, LIANG Hao, YUN Ting, LI Rong-Feng
    Scientia Agricultura Sinica. 2012, 45(2):  359-368.  doi:10.3864/j.issn.0578-1752.2012.02.019
    Abstract ( 775 )   PDF (675KB) ( 1259 )   Save
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    【Objective】The objective of this study is to construct two replacement targeting vectors for knocking-out bovine MSTN gene. 【Method】 Primers with restricted endonucleases locus were designed and synthesized. The short arms and long arms for both vectors were isolated from the genomic DNA of cattle by polymerase chain reaction (PCR). Then, these fragments were cloned into basic targeting vectors pMCS-PLP and PⅢ to construct two replacement targeting vectors (pPLP-MSTN and PⅢ-MSTN), respectively.【Result】Two constructed gene targeting vectors were identified by PCR, T-vector ligation and DNA sequencing. The 2.8 kb short arm and the 4.0 kb long arm were detected in the targeting vector pPLP-MSTN, and the 1.3 kb short arm and the 6.8 kb long arm were detected in the targeting vector PⅢ-MSTN.【Conclusion】Two replacement targeting vectors for knocking-out bovine MSTN gene were successfully constructed. The targeting vector pPLP-MSTN is a traditional knock-out vector without a negative-selecting gene, and the targeting vector PⅢ-MSTN is a promoter trap vector with EGFP without a negative-selecting gene.
    Study and Application of Induced Pluripotent Stem Cells
    MIAO Xiang-Yang, CHEN Xiao-Ying
    Scientia Agricultura Sinica. 2012, 45(2):  369-375.  doi:10.3864/j.issn.0578-1752.2012.02.020
    Abstract ( 719 )   PDF (592KB) ( 1306 )   Save
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    The study of induced pluripotent stem cells (iPS cells/iPSCs) has become hot spot of stem cell research since the mouse embryonic fibroblast and tail tip fibroblast were successfully reprogrammed to iPSCs. Compared with embryonic stem cells, iPS cells have many advantages, such as simple operation and high stability. The iPSCs has potential values in both the fundamental study of biology and clinical application. iPS cells’ application would be very useful in various fields, for example, creating genetic models for human diseases, obtaining transgenic animals for organ transplantation therapies, improving animal production traits and disease resistance, as well as for bio-pharmaceuticals and so on. In addition, the application of iPSCs would have a great significance for solving the long-standing problems of stem cell research ethical issues and immune rejection. With the combination of gene therapy and cell transplantation therapies, the iPSCs research findings have been applied to animal disease models and transgenic animals. And iPS cells technology elicits a great promise for patient-specific cell therapy and development of gene targeted drugs. Furthermore, the technology also provides a novel platform for the research of iPS cells reprogramming mechanism and pathological process of human disease. However, at the present stage iPSCs’ research is just beginning and there is still much work to do before iPSCs can be considered as a clinically reliable cell source. The research progress, current situation and future application prospects of iPSCs technology were discussed in the paper.
    Coupling Effect of Water and Fertilizer on Yield and Silage Quality of Maize
    FENG Peng, WANG Xiao-Na, WANG Qing-Li, SUN Qi-Zhong, ZHAO Shu-Fen
    Scientia Agricultura Sinica. 2012, 45(2):  376-384.  doi:10.3864/j.issn.0578-1752.2012.02.021
    Abstract ( 952 )   PDF (666KB) ( 1005 )   Save
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    【Objective】 The objective of this study is to research on the effect of coupling between water and fertilizer on maize yield, fermentation quality, nutritional value and the water use efficiency. 【Method】 Urea (0, 75, 225, 300 kg•hm-2) and water (0, 2 299.95, 2 069.96, 1 839.96 m3•hm-2) were all four levels. By measuring the yield and indicators of silage quality of maize, the effective utilization way of coupling between fertilizer and water were studied. Yields, lactic acid, acetic acid, propionic acid, butyric acid, ammonia nitrogen, buffering capacity, dry matter, crude protein, neutral detergent fiber, acid detergent fiber, crude ash, ether extract, and water-soluble carbohydrates were determined. 【Result】 The results showed that the yield when the irrigation water was at 2 069.96 m3•hm-2, fertilizer urea at 225 kg•hm-2 was the highest, as much as 87 229.87 kg•hm-2. The content of lactic acid of fertilizer urea at 225 kg•hm-2 treatments (W0N2, W1N2, W2N2, W3N2) was higher than others (P<0.05), and 11.96%, 15.03%, 12.58%, 15.64% higher than CK, respectively. Silage consumed water soluble carbohydrates, reduced detergent fiber of raw, and improved digestibility, the neutral detergent fiber and acid detergent fiber in treatment of irrigation water at 2 069.96 m3•hm-2 and fertilizer urea at 225 kg•hm-2 was the lowest, and DM was 53.61% and 28.39%, respectively. 【Conclusion】 The water utilization efficiency was increasing with irrigation water volume. Application of urea can facilitate water use efficiency, especially in arid and semiarid region. So it is an effective way to increase yield and water use efficiency of maize. The yield and silage quality of the treatment of irrigation water 2 069.96 m3•hm-2 and fertilizer urea 225 kg•hm-2 were the best.
    VETERINARY SCIENCE
    Study of Class I Integrons in qnr-positive Enterobacteriaceae Isolates from Animals
    YUE Lei, CHEN Xue-Ying, ZHUANG Na, HE Jia-Xin, SHI Wei, LIAO Xiao-Ping, LIU Ya-Hong
    Scientia Agricultura Sinica. 2012, 45(2):  385-390.  doi:10.3864/j.issn.0578-1752.2012.02.022
    Abstract ( 738 )   PDF (568KB) ( 525 )   Save
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    【Objective】The objective of this study is to investigate the prevalence of class 1 integrons in qnr-positive enterobacteriaceae isolates from animals. 【Method】 Fourteen qnr-positive strains of Enterobacteriaceae from animals were screened for class 1 integrase gene intI by PCR and sequencing. Gene cassettes of the detected class 1 integrons were studied by PCR using LA Taq enzyme and sequencing.【Result】intI1 was detected in all the 14 qnr positive strains tested. And more than two resistance genes were found in each cassette. The genes most commonly found in integrons were dihydrofolate reductase (dfr) gene for trimethoprim resistance and adenylvltransferase (aadA) gene for amino glycoside resistance. Lincosamide nucleotidyltransferase linF gene and ribosyl transferase arr-3 gene for rifampin resistance were also detected in this study. Plasmid-mediated quinolone resistance aac (6')-Ib-cr was found following an empty cassette. dfrA27-aadA2, dfrA12-orfF-aadA2 and dfrA17-aadA5 were the major arrays.【Conclusion】It seems that the class 1 integrons are extensively existed in qnr positive strains.
    Effect and Mechanism of Kisspeptin-10 on Progesterone Secretion in Granulosa Cells of Chicken F1 Follicles Cultured in Serum-Free Medium
    XIAO Yun-Qi, HUANG Yan-Bing, WU Jing, NI Ying-Dong, ZHAO Ru-Qian
    Scientia Agricultura Sinica. 2012, 45(2):  391-398.  doi:10.3864/j.issn.0578-1752.2012.02.023
    Abstract ( 712 )   PDF (297KB) ( 687 )   Save
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    【Objective】The objective of this study was to investigate the effect and mechanism of Kisspeptin-10 (Kp-10) on progesterone (P4) secretion in cultured granulose cells of chicken follicles.【Method】Two-hundred-day ISA laying hens were sacrificed before the expected time to ovulation. The follicles (F1) were collected and the granulosa cells were isolated and cultured in serum medium for one day, and then cultured in serum-free medium. After one day stabilization in serum-free medium, the granulosa cells were treated with different concentrations of Kp-10 alone or in combination with U73122, EGTA and/or Ca2+ for 24 h, respectively. The media was collected for measuring P4 by radioimmunoassay (RIA).【Result】The cells were determined to be kisspeptin-positive expression with specific antibody against Kp-10. After 24 h treatment, Kp-10 significantly increased the viability of granulosa cells as well as P4 secretion (P<0.05). U73122 (PLC inhibitor) at 0.5 μmol•L-1 and 2 μmol•L-1 blocked the effect of Kp-10 on stimulating P4 secretion markedly (P<0.05), while 2 μmol•L-1 U73122 had no effect on P4 secretion. Verapamil (the calcium channel blocker) suppressed P4 secretion in a dose-dependent manner, reaching the statistical significance at 100 μmol•L-1 dosage (P<0.05). Under low dosage of Verapamil (1 μmol•L-1) background, 100 nmol•L-1 Kp-10 can still significantly increase P4 secretion (P<0.05). However, under higher dosage of Verapamil (10 or 100 μmol•L-1), 100 nmol•L-1 Kp-10 could not reverse the significant decrease of P4 secretion by Verapamil in medium of in vitro cultured granulosa cells. Flow cytometric analysis showed that the level of intracellular Ca2+ was consistent with progesterone secretion. P4 secretion induced by Kp-10 was decreased significantly in the presence of EGTA (1 and 5 mmol•L-1), while this effect was converted by adding 1.5 mmol•L-1 Ca2+ (P<0.05). 【Conclusion】 Kisspeptin-10 increase P4 secretion in granulosa cells of ISA hens' follicles cultrured in serum-free medium, and the mechanism might be associated with intracellular Ca2+ concentration.
    RESEARCH NOTES
    An Efficient Method of Qualitative Screening Positive Transgenic Samples Based on PCR Technique and Pooling Strategy
    LIU Wen-Wen, HAO Zhuan-Fang, WENG Jian-Feng, LI Xin-Hai, SONG Xin-Yuan, ZHANG Shi-Huang, XIE Chuan-Xiao
    Scientia Agricultura Sinica. 2012, 45(2):  399-404.  doi:10.3864/j.issn.0578-1752.2012.02.024
    Abstract ( 1031 )   PDF (564KB) ( 1407 )   Save
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    【Objective】 The objective of this study is to establish an efficient method of qualitative screening a few of transgenic-positive individuals from a large number of samples based on PCR technique and DNA pooling strategy.【Method】 In a case study, 480 samples were randomly numbered and then a virtual 3 dimensional pooling bulks of template DNA were constructed. Each of 480 samples was put into 5×96-well plates well by well. The row pools, X dimension pools, were the samples from same row number of all plates and therefore 8 (A, B, C, …… G, H) pools were made. The line pools, Y dimension pools, were the samples from same line number of all plates and therefore 12 (1, 2, 3, ……11, 12) pools were made. The plate pools, Z dimension pools, were the samples from the same plate and therefore 5 (I, II, III, IV, V) pools were made. The rationals of the design was used in order to archive high efficiency because the cross among 3 dimensions is unique along with high sensitivity and specificity be provided with PCR technique. The 500 ng•µL-1 positive samples were 96× diluted by using ddH2O or negative DNA, respectively. At the same time, 13 double blind samples of Bt176 events, Bt176 and Cry1Ab positive samples, were mixed in 480 samples. By screening the 25 pools, the candidate samples were detected and then screened them again. 【Result】 The results showed that the sensitivity and specificity of the detection were not affected. What’s more, this way exactly screened out 13 positive samples after screening of 25 pools and they were the positive 13 samples. 【Conclusion】 This method can be used for screening a few numbers of positive individuals from a large number of accessions. The work load will be reduced around 80% compared with conventional sample by sample method.