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Table of Content

    15 May 2011, Volume 44 Issue 10
    CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    Physiological Character and Gene Fine Mapping of a Virescent Mutant v13(t) in Rice (Oryza sativa L.)
    WANG Jun, YANG Jie, CHEN Zhi-De, FAN Fang-Jun, ZHU Jin-Yan, YANG Jin-Huan, ZHONG Wei-Gong
    Scientia Agricultura Sinica. 2011, 44(10):  1973-1979.  doi:10.3864/j.issn.0578-1752.2011.10.001
    Abstract ( 675 )   PDF (515KB) ( 1124 )   Save
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    【Objective】On the basis of phenotypic characterizations of temperature sensitive virescent mutant v13(t), the gene virescent 13(t) was finely mapped. 【Method】 One natural virescent mutant, named virescent 13(t), was identified from the indica rice cultivar 9311. The physiological basis of the phenotypic variation was observed by transmission electron microscope. And a map-based cloning strategy was employed to reveal the genetic basis of this variation. 【Result】 At low temperature conditions (<26℃), the initial three leaves of v13(t) showed white, with little green tips and sheath, and the seedling gradually died. At 28℃, only the leaf tips and edge appeared white, and then the leaves turned green. While at 30℃, a significant difference between it and wild-type was not observed. To uncover the genetic basis of this variation, an F2 segregating population, v13(t) mutant, was developed by crossing v13(t) and Wuyunjing 7. Genetic analysis indicated that this leaf color variation was controlled by one recessive nuclear gene. Gene V13(t) was initially mapped between the SSR markers RM3638 and RM459 on chromosome 5, with the genetic distance of 3.2 cM and 0.5 cM, respectively. Several new InDel markers around the V13(t) region were further developed for fine mapping. The target gene was finally delimited to a 98.9 kb region between markers InDel5-11 and InDel5-8 on BAC AC130729, and segregated with marker InDel5-2. 【Conclusion】 One new temperature sensitive virescent mutant v13(t) was controlled by one recessive nuclear gene V13(t), and V13(t) was finally delimited to a 98.9 kb region on BAC AC130729.
    Genetic Overlap Between Salt and Low-Temperature Tolerance Loci at Germination Stage of Soybean
    QIU Peng-Cheng, ZHANG Wen-Bo, JIANG Hong-Wei, LIU Chun-Yan, LI Can-Dong, FAN Dong-Mei, ZENG Qing-Li, HAN Dong-Wei, HU Guo-Hua, CHEN Qing-Shan
    Scientia Agricultura Sinica. 2011, 44(10):  1980-1988.  doi:10.3864/j.issn.0578-1752.2011.10.002
    Abstract ( 585 )   PDF (369KB) ( 507 )   Save
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    【Objective】The main purpose of this paper was to map the QTLs related with salt tolerance and low-temperature tolerance at germination stage with backcross introgression lines (ILs), and analyze the genetic overlap between them. These overlapping QTL loci could be used to breed soybean varieties with both salt tolerance and low-temperature tolerance, improve efficiency of stress-tolerance breeding. 【Method】A primary backcross introgression lines (ILs) were constructed with Hong-feng11 as recurrent parent and Harosoy as donor parent. Then 48 individuals from BC2F4 introgression populations were obtained after screening in 1.75% NaCl solution, and 40 individuals were screened out after 6℃ low-temperature treatment comparing with the Hong-feng11 at germination stage. The QTL identification of the germination stage was conducted by chi-square test and analysis of variances with the two introgression populations. 【Result】There were 22 QTL located with BC2F4 introgression populations after salt stress, and 15 QTL were mapped after low-temperature stress. Seven overlapping QTLs between salt tolerance and low-temperature tolerance were detected on 6 linkage groups at germination stage. 【Conclusion】In total, there were 31.81% of salt tolerance and low-temperature tolerance loci existed genetic overlap.
    Introduction of Bt cry1Ah Gene into Sweet Sorghum (Sorghum bicolor L. Moench) by Agrobacterium tumefaciens-Mediated Transformation
    ZHU Li, LANG Zhi-Hong, LI Gui-Ying, HE Kang-Lai, YUE Tong-Qing, ZHANG Jie, HUANG Da-Fang
    Scientia Agricultura Sinica. 2011, 44(10):  1989-1996.  doi:10.3864/j.issn.0578-1752.2011.10.003
    Abstract ( 881 )   PDF (462KB) ( 699 )   Save
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    【Objective】 The aim of the study is to establish a high frequency and steady Agrobacterium tumefaciens- mediated transformation system of sweet sorghum, and validate the insecticidal function of a novel Bt cry1Ah gene in the transgenic plants.【Method】Using the callus induced from immature inflorescence as transformation recipients, the codon optimized Bt cry1Ah was transferred into sweet sorghum varieties “BABUSH” and “MN-3025” via Agrobacterium-mediated transformation. The obtained regenerative plants were identified by PCR, RT-PCR analysis, and their herbicide resistance, the expression of aim protein and insect-resistant identification were also analyzed.【Result】After gradient selection with Biolaphos, a total of 66 regenerated plants were produced from 336 agroinfected calli in these two sweet sorghum varieties. Among these plants, 22 PCR positive transformed plants of 8 independent transformation events were obtained, and the average transformation efficiency was 2.38%. The transcription of cry1Ah gene in the T0 transgenic sweet sorghum plants was further confirmed by RT-PCR. The Bt proteins could be detected by western blotting and ELISA assay in five transgenic plants, which showed different expression levels in a range of 1.93 ng•g-1 FW to 165.69 ng•g-1 FW, with an average of 87.50 ng•g-1 FW. Additionally, the results of bioassay indicated that two of the five transgenic plants displayed high insect-resistance to Ostrinia furnacalis.【Conclusion】An Agrobacterium-mediated genetic transformation system of sweet sorghum was established by using the callus derived from immature inflorescence as the recipients. The resulted T0 generation transgenic sweet sorghum plants with cry1Ah showed high insect-resistance to Ostrinia furnacalis. Further investigations on the genetic stability of cry1Ah in different transgenic lines and generations are undergoing.
    TILLAGE & CULTIVATION·PHYSIOLOGY & BIOCHEMISTRY·AGRICULTURE INFORMATION TECHNOLOGY
    Modeling Plant Nitrogen Uptake and Grain Protein Accumulation in Rice
    CHEN Jie, TANG Liang, LIU Xiao-Jun, CAO Wei-Xing, ZHU Yan
    Scientia Agricultura Sinica. 2011, 44(10):  1997-2004.  doi:10.3864/j.issn.0578-1752.2011.10.004
    Abstract ( 613 )   PDF (506KB) ( 840 )   Save
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    【Objective】Grain protein content is an important quality index in rice. The objective of this study was to develop a process based simulation model for predicting the content and accumulation of grain protein under different cultural conditions. 【Method】On the basis of the field experiments involving different eco-sites, cultivar types and nitrogen rates, the fundamental relationships between grain protein accumulation and environmental and genetic factors were quantified by modeling the processes of nitrogen assimilation and partitioning within plant. 【Result】The model proposed that the rate of individual grain nitrogen accumulation was determined by the nitrogen availability restricted by source and nitrogen accumulation rate restricted by sink. Nitrogen availability of individual grain restricted by source was the sum of nitrogen uptake and remobilization from the vegetative organs post-anthesis, whereas nitrogen accumulation rate restricted by sink was dependent on potential nitrogen accumulation rate and interactive effects of temperature, water and nitrogen factors. Post-anthesis nitrogen uptake exhibited a logarithmic relationship to increasing grain weight. Nitrogen remobilization from the vegetative organs was provided from nitrogen accumulated in both leaves and stems. Relative nitrogen contents in leaves and stems pre-anthesis linearly increased with the accumulative growing degree-days after sowing, while those post-anthesis linearly decreased with the growing degree-days. The model was tested using the independent data sets of different years, eco-sites, cultivars, nitrogen rates, and it exhibited a good fit between the simulated and observed values, with the R2 of 0.968, 0.980, 0.974, 0.970 and 0.976, and RMSE of 16.55%, 13.24%, 9.53%, 10.93% and 9.29% for nitrogen uptake amounts of leaf and stem before anthesis, grain nitrogen uptake amount after anthesis, and nitrogen translocation amount of leaf and stem after anthesis, respectively, with the RMSE of 7.82% and R2 of 0.930 for grain protein content, respectively.【Conclusion】The simulation model based on nitrogen assimilation and translocation in rice could give a reliable prediction of plant nitrogen uptake and translocation amounts, and grain protein content and accumulation under different cultural conditions, which would provide a quantitative tool for grain quality prediction.
    Effects of Wheat and Maize Straw Returned to the Field on Lodging Resistance of Maize in Lime Concretion Black Soil Region
    SHEN Xue-Shan, LI Jin-Cai, QU Hui-Juan, WEI Feng-Zhen, ZHANG Yi, WU Wen-Ming
    Scientia Agricultura Sinica. 2011, 44(10):  2005-2012.  doi:10.3864/j.issn.0578-1752.2011.10.005
    Abstract ( 726 )   PDF (305KB) ( 589 )   Save
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    【Objective】 The objective of the experiment is to study the effects of straw returned to the field on lodging resistance of maize in lime concretion black soil region. 【Method】 Maize cultivar Zhengdan 958 was grown in this plot experiment to investigate the effects of straw returned to the field on lodging resistance of maize. 【Result】 The results showed that wheat or maize straw returned to the field could increase aerial root number, root number in 0-30 cm soil layer and root weight, so as the plant height and fresh weight of maize. After straw returning, the length, diameter, dry weight and ratio of dry weight to length of internodes from bottom 3rd to 7th were increased especially the stalk crash strength and stalk rind penetrain strength of bottom internodes were significantly increased at silking and filling stage. In addition, the root lodging coefficients were a significantly decreased while the lodging resistance indexes were significantly increased. The correlation coefficient showed that there was significant positive correlation between root lodging coefficient and root lodging percentage while there was a negative significant correlation among root lodging coefficient, fresh weight, root weight and stalk crash strength of bottom 3rd internode. The relation between total lodging percentage and internode length was a very significant post ive correlation while that among total lodging percentage and the dry weight, plumpness, crash strength and rind penetrain strength of internodes were a significant negative correlation. 【Conclusion】Therefore, under the condition of wheat and maize straw returned to the field, the root lodging percentage and stalk breaking percentage of maize would be decreased while the grain yield would be increased.
    Study on Changes of Color Parameters and Pigment Contents in Flue-cured Tobacco Leaves with Different Maturities During Bulk-curing Process
    HUO Kai-Ling, SONG Chao-Peng, WU Sheng-Jiang, LIU Chuang, HE Fan, GONG Chang-Rong
    Scientia Agricultura Sinica. 2011, 44(10):  2013-2021.  doi:10.3864/j.issn.0578-1752.2011.10.006
    Abstract ( 1023 )   PDF (425KB) ( 686 )   Save
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    【Objective】 Changes of color parameters and pigment contents in flue-cured tobacco leaves with different maturities and their relationships during bulk curing process were studied in order to provide a theoretical basis for optimization and perfection of curing technology.【Method】Automatic color difference meter and spectrophotometer were used to study the color parameters(L*, a*, b*) and chromaticity parameters(△L*, △a*, △b*) , chlorophyll and carotenoid content of unripe, immature, ripe and overripe tobacco leaves during bulk curing process. 【Result】 During bulk curing process, both L* and a* value of flue-cured tobacco leaves of different maturities showed an ascending tendency. The b*value of flue-cured tobacco leaves with four different maturities increased before 48℃, decreased between 48℃ and 54℃, and then rose again slightly. L* value of flue-cured tobacco leaves with four different maturities showed as overripe > ripe > unripe > immature, there was little difference in a* value between four kinds of fresh tobacco leaves, among which high maturity ascended quicker, and b* of flue-cured tobacco leaves showed as immature > unripe > overripe > ripe. △L* values of flue-cured tobacco leaves with four different maturities decreased generally during bulk curing process, △a* increased obviously at 48℃ and △b* reduced, especially unripe and overripe flue-cured tobacco leaves. Correlation analysis showed that there was a significant relationship between carotenoid content and L* value in immature, ripe flue-curing tobacco leaves. Regression equation between L*, a*, b* and pigments in ripe flue-cured tobacco leaves was established during bulk curing process, (r = - 0.979, - 0.851, P < 0.05), carotenoid content was clearly negatively correlated with a* value (r = - 0.832, - 0.853, P < 0.05), which equation between L*, a*, b*and pigments in ripe flue-cured tobacco leaves was, established during bulk-curing process, which respectively were followed as:  = 245.67 x1 + 114.75 x2 - 211.69 x3 - 125.21 x4 + 118.69;  = 416.9 x1 + 369.19 x2 - 404.38 x3 - 78.38 x4 + 43.55;  = - 1051.55 x1 - 1270.02 x2 + 1106.42 x3 + 17.48 x4 + 40.1.【Conclusion】Color values of front and back of flue-cured tobacco leaves with different maturities had similar changing trend during bulk-curing process, color parameters of flue-curing showed a positive correlation with pigment contents, and color parameters could be used as an auxiliary index to judge the maturity of flue-cured tobacco.
    PLANT PROTECTION
    SSR Mapping of Leaf Rust Resistance Gene LrY192 in Aegilops tauschii Y192
    HU Ya-Ya, FENG Li-Na, JI Hong-Liu, SUN Yi, ZHANG Na, WEI Xue-Jun, YANG Wen-Xiang, LIU Da-Qun, JIA Ji-Zeng
    Scientia Agricultura Sinica. 2011, 44(10):  2022-2028.  doi:10.3864/j.issn.0578-1752.2011.10.007
    Abstract ( 535 )   PDF (525KB) ( 485 )   Save
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    【Objective】 The objective of this study is to find new leaf rust resistance gene in Aegilops tauschii, and provide valuable information and germplasm for wheat leaf rust resistance breeding.【Method】 Hybridization between Ae. tauschii Y192 (resistant) and Ae. tauschii Y2272 (susceptible) was carried out and the resistance of F2 population was evaluated by inoculated Puccinia triticina for investigating the resistance genes in Y192. Bulk segregation analysis and microsatellite markers on chromosome D were used to tag the resistance gene in Y192. The genetic distance was calculated by MapChart software. Gene postulation and MAS were also used to identify the resistance genes in Y192. 【Result】 F1 population derived from the crossing Y192 and Y2272 were resistant, and the ratio of resistance/susceptible was 3:1 in F2 generation. This indicated that a dominant wheat leaf rust resistance gene was presented in Y192. The gene was temporarily designated as LrY192.Three microsatellite markers Wmc245, Xgwm296 and Xgwm261 were acquired from SSR markers and linked to LrY192 with genetic distance of 4.1, 18.9, and 26.2 cM, respectively. According to the locations of the linked markers, the resistance gene was located on chromosome 2D. 【Conclusion】 Based on the chromosomal location and the resistance pattern of the gene, it is concluded that LrY192 is a novel leaf rust resistance gene, and could be selected by Wmc245.
    cDNA Cloning, Prokaryotic Expression and Polyclonal Antibody Preparation of GOBP2 from Ostrinia furnacalis (Guenée)
    CHENG Xiao-Dong, AN Shi-Heng, WANG Hai-Ting, WANG Tian-Tian, LUO Mei-Hao, GUO Xian-Ru, YUAN Guo-Hui
    Scientia Agricultura Sinica. 2011, 44(10):  2029-2038.  doi:10.3864/j.issn.0578-1752.2011.10.008
    Abstract ( 663 )   PDF (1109KB) ( 602 )   Save
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    【Objective】The objective of this study is to clone and express in prokaryotic system of a novel cDNA, named OfurGOBP2, encoding the general odorant binding protein GOBP2 from Ostrinia furnacalis (Guenée). 【Method】The cDNA encoding OfurGOBP2 was isolated from Ostrinia furnacalis (Guenée) antennae by using reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE). The open reading frame (ORF) of OfurGOBP2 was further cloned into prokaryotic cells to test its expression. 【Result】 Sequencing and structural analysis showed that the ORF of OfurGOBP2 was 489 bp in size, encoding 162 amino acid residues (GenBank accession no. DQ673101). GOBP2 contains six conserved cysteine residues, consistent with the characteristics of odorant binding protein. The homologue analysis revealed that Ostrinia furnacalis GOBP2 shared 70% identity with other insects GOPB2, which indicated that insect GOPB2 is conserved in evolutional process. GOBP2 was further ligated with pGEX-4T-2 vector and then transformed into Escherichia coli BL21 (DE3). SDS-PAGE and Western-blot results revealed that GOBP2 was expressed in E. coli. The molecular weight of expressed protein was consistent with the predicted molecular weight of OfurGOBP2. Anti-GOPB2 antibody specifically recognized OfurGOBP2 from antenna by using Western blot. 【Conclusion】In this study, OfurGOBP2 was cloned and expressed in prokaryotic expression system, and the polyclonal antibody was further prepared, which is helpful for further researches on molecular structure and function of OfurGOBP2.
    SOIL & FERTILIZER·WATER-SAVING IRRIGATION·AGROECOLOGY & ENVIRONMENT
    Effect of Soil Compaction on Spatio-temporal Distribution and Activities in Maize Under Different Soil Types
    WANG Qun, LI Chao-Hai, LI Quan-Zhong, XUE Shuai
    Scientia Agricultura Sinica. 2011, 44(10):  2039-2050.  doi:10.3864/j.issn.0578-1752.2011.10.009
    Abstract ( 818 )   PDF (561KB) ( 731 )   Save
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    【Objective】The objective of this study was to identify the spatial and temporal responses of root distribution, root activities and yield in maize to soil compaction in different soils.【Method】A two-year, 2007-2008, barrel-culture experiment was conducted with three soil types and two levels of soil compaction on the Experimental Farm of Henan Agricultural University. The characteristics of spatial and temporal distribution of roots, root activities and yield in maize were studied. 【Result】The results showed that root morphological indexes and yield were restricted in the three selected soils under soil compaction stress. The maximum length, dry weight, volume, and activities of roots and yield were found in the fluvo-aquic soil while the minmum were observed in the yellow cinnamon soil. The total and active absorbing areas of root per plant and dehydroganase activity of root were significantly different among the three selected soils with highest in the fluvo-aquic soil, followed by the lime concretion black soil and yellow cinnamon soil. Ratio of absorbing area and ratio of active absorbing area to dry root weight were increased under soil compaction stress. With the relief of soil compaction, root morphological and physiological parameters increased significantly in all selected soils, resulting in the increase of yield. The density of root length and dry root weight were increased significantly in the 20-40 cm soil layers compared with that in 0-20 cm soil layer in the three selected soils, but the ratio of absorbing area and the ratio of active absorbing area to dry root weight were decreased with decreases of soil compaction in three soils. The changes of root parameters and yield in lime concretion black soil and yellow cinnamon soil were more sensitive than in the fluvo-aquic soil.【Conclusion】Root growth and distribution were restricted under high soil compaction. This clearly showed that plants were not passively tolerant to soil compaction stress,but actively regulated their physiological metabolic processes to reduce injury by the environment. Response of maize root soil to soil compaction stress in the three selectedl soils was closely related to soil physical properties.
    Indexes of Salt Tolerance of Cotton in Akesu River Irrigation District
    ZHANG Yu, WANG Li-Hong, SUN San-Min, CHEN Xiu-Long, LIANG Yu-Ji, HU Shun-Jun
    Scientia Agricultura Sinica. 2011, 44(10):  2051-2059.  doi:10.3864/j.issn.0578-1752.2011.10.010
    Abstract ( 756 )   PDF (418KB) ( 615 )   Save
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    【Objective】This experiment is to construct the linear subsected functions and the nonlinear S-shaped functions between the cotton relative yield and soil salt content in the salinized soil in Akesu River Irrigation District and to determine the index of cotton salt tolerance.【Method】The linear regression and the nonlinear least square approximation were used to deduce two yield response functions of cotton to soil salt content, which are respectively for the 0-20 cm soil layer and the 0-40 cm soil layer, based on experimental data from the four observation points during the three years, whose applicability were analyzed and compared and then the indexes of cotton salt tolerance were drawn up with the function with better applicability. 【Result】 Both the linear subsected functions and the nonlinear S-shaped functions were founded for the 0-20 cm soil layer and the 0-40 cm soil layer. It was found that the nonlinear S-shaped function fitted better with the response relationship between the cotton relative yield and the soil salt content in the salinized soil in Akesu River Irrigation District than others.【Conclusion】The cotton critical soil salt content the cotton threshold soil salt content, the soil salt content at the fastest rate of cotton relative yield reduction, and the soil salt content at the 50% cotton relative yield reduction are respectively 0.302%, 1.119%, 0.558%, 0.581% (0-20 cm soil layer) in Akesu River Irrigation District.
    Fourier and Wavelet Analysis of Phosphorus Concentration Time Series in Baihe River in Miyun Reservoir Upstream Watershed
    ZHANG Wei-Wei, LI Hong, SUN Dan-Feng, ZHOU Lian-Di
    Scientia Agricultura Sinica. 2011, 44(10):  2060-2069.  doi:10.3864/j.issn.0578-1752.2011.10.011
    Abstract ( 743 )   PDF (991KB) ( 797 )   Save
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    【Objective】Analyzing the long-term water quality monitoring data to find temporal pattern of water quality signals over different temporal scales can assist us in understanding various processes affecting water quality temporal evolution at different scales and further ensuring watershed water quality security. 【Method】 Taking the phosphorus monitoring data of two sites S1 and S2 in the period 1986-2003 in Baihe River lying Miyun reservoir upstream watershed as a case, time domain analysis method, Fourier and Wavelet analysis were adopted to explore and compare the periodic patterns and temporal pattern characteristics of the two sites. 【Result】 The results showed that the Time Domain analysis method was not adopted due to no serial correlation and heteroscedasticity in each site series. The periodic patterns of two sites were discovered using Fourier analysis. The site S1 had a period of six years, while the site S2 had two periodic patterns of two years around and six years. The temporal pattern characteristics at different scales were obtained through wavelet analysis, which were at moderate scale for the site S1, while at moderate and small scales for the site S2. 【Conclusion】 The Fourier and wavelet analysis method can both be used in the study of surface water quality temporal change pattern, the first is a coarse method and the latter is a more detailed method for analyzing surface water quality temporal pattern characteristics.
    HORTICULTURE
    Effect Function of NPK Fertilization, N Fertilization in Different Stages and Its Application in Formula Fertilization on Cauliflower 
    LI Guang-Qing, XIE Zhu-Jie, YAO Xue-Qin
    Scientia Agricultura Sinica. 2011, 44(10):  2070-2080.  doi:10.3864/j.issn.0578-1752.2011.10.012
    Abstract ( 584 )   PDF (380KB) ( 767 )   Save
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    【Objective】 The purpose of the study is to establish effect function models of N, P, K fertilizer balanced application and the N fertilizer application in different stages for winter cauliflower and to apply that in soil test for fertilization according to calculation formula of recommended fertilization rate toward different production targets.【Method】Using a mid-maturity winter cauliflower variety ‘120 Tian’, the “311-A” optimization regression design was used to conduct field experiments of N, P, K fertilizers and to build the models of the effect of balanced N, P, K fertilization , N fertilizer application and content of glucoraphanin.  Simplex lattice design was used to conduct field experiments of N fertilizer in different stages and to build the model of the effect of N fertilization. The combination of fertilization effect model and soil test analysis could further recommend the optimal fertilization for cauliflower production.【Result】There were extremely significant correlation between yield, appearance eligibility ratio and the coded value of N, P, K. The N, P, K optimal combination on yield was N 327.83 kg•hm-2, P2O5 89.65 kg•hm-2, K2O 201.41 kg•hm-2, and the maximum yield was 19 089.25 kg•hm-2. Further analysis showed that a good distribution ratio of N fertilizer application rates before field planting, at the early growth stage and at later growth stage was 0.4313:0.2427:0.3260. The N, P, K optimal combination on appearance eligibility ratio was N 434.20 kg•hm-2, P2O5 90.11 kg•hm-2, K2O 213.92 kg•hm-2, and the maximum appearance eligibility ratio was 84.95%. There were significant effects on the content of glucoraphanin by applying N fertilizer. When N fertilizer application reached 394.62 kg•hm-2, glucoraphanin content would get to maximum. The optimal fertilization for cauliflower production of 30 field parcels could further recommend by the combination of fertilization model and soil test analysis, according to calculation function of recommended fertilization rate toward different production targets. The results showed that the different optimal combinations of applying N, P, K fertilizers could be carried on, according to the different targets and soil nutrient level. For example, toward the maximum yield of 30 different plots, the maximum of recommended N, P and K fertilization rate were 7.92%, 10.21%, and 68.39% more than the minimum, respectively. 【Conclusion】 Toward the different plots and production targets, the N, P, K fertilization rate could be recommended according to the optimal fertilization effect function model and recommendation calculation function.
    Molecular ID Establishment of Main China Peach Varieties and Peach Related Species
    CHEN Chang-Wen, CAO Ke, WANG Li-Rong, ZHU Geng-Rui, FANG Wei-Chao
    Scientia Agricultura Sinica. 2011, 44(10):  2081-2093.  doi:10.3864/j.issn.0578-1752.2011.10.013
    Abstract ( 773 )   PDF (529KB) ( 822 )   Save
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    【Objective】 A total of 237 peach germplasms including China landraces, bred varieties, and related species selected from national grape and peach repository of Zhengzhou were studied with SSR(simple sequence repeat) markers. Analysis was made to establish the 237 peach germplasms molecular ID and to study the methods for distinguishing the germplasms more simply.【Method】Germplasms were distinguished with selected SSR markers, bands that amplified by each marker were coded, then combined the code as a molecular ID. 【Result】The results showed that after screening of the 80 primers, 203 alleles were detected using 16 selected SSR markers located on each chromosome of peach, with a mean value of 12.7 alleles/locus. There were 123 selected alleles were coded to establish germplasms molecular ID based on strategy that alleles located both in landraces, bred and related germplasms. 【Conclusion】There were 202 out of 237 germplasms could be identified with an particular combined code numbers. Moreover, the identifying efficiency of different combinations of the primers were analyzed, 176 germplasms could be identified using 8 reduced core primers, with an average value of 22.1 germplasms/primers. The remaining primers have a higher identifying efficiency and more germplasms could be identified separately. At last, for distinguish germplasms more simply, through selection of the primer pairs according to its PIC step by step, the germplasms could be distinguished by a practical primer choice.
    Analysis of Main Organic Acid Compositions in Rosa roxburghii Tratt
    AN Hua-Ming, LIU Ming, YANG Man, FAN Wei-Guo
    Scientia Agricultura Sinica. 2011, 44(10):  2094-2100.  doi:10.3864/j.issn.0578-1752.2011.10.014
    Abstract ( 781 )   PDF (380KB) ( 999 )   Save
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    【Objective】 The objective of the study is to analyze the components of organic acids and content of ascorbic acid in Rosa roxburghii Tratt.【Method】The organic acid components in Rosa roxburghii Tratt ‘Guinong 5’ and their contents in various organs, in developing fruit and during fruit storage were analyzed by using high performance liquid chromatographic (HPLC). 【Result】 The results showed that, besides ascorbate, 6 organic acid components, including malic acid, lactic acid, tartaric acid, citric acid, oxalic acid and succinic acid were detected in this plant, with different concentrations in different organs. In root, lactic acid and tartaric acid dominate and in stems and leaves there were rich in lactic acid, while in flowers it is succinic acid mainly accumulated. In the period of fruit development, the content of ascorbic acid presented an increasing trend but that of other components showed increase firstly and then decreased. Ascorbic acid content, accounting for about 67% of total acid, predominated in mature fruit. However, only for 6 organic acid components, the highest content of malic acid accounted for about 53% and followed by lactic acid (about 30%). The study also showed that storage temperature of 4℃ is good for maintenance of organic acids and ascorbate in the fruit.【Conclusion】Rosa roxburghii belongs to the malic acid-type fruit with a unique characteristic of richness of ascorbic acid.
    Effect of High Temperature on the Flower Development of    Sweet Cherry in Solar Greenhouse
    LI Yan, LI Ling, LI Shao-Xuan, WANG Hui, YE Bao-Xing, GAO Dong-Sheng
    Scientia Agricultura Sinica. 2011, 44(10):  2101-2108.  doi:10.3864/j.issn.0578-1752.2011.10.015
    Abstract ( 643 )   PDF (567KB) ( 604 )   Save
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    【Objective】 The aim of the experiment is to explore the reasons of low flowering quality of cherry cultured in greenhouse.【Method】 Effects of high temperature on flower development and flowering time of sweet cherry were studied using 4-year-old potted ‘Hongdeng’ sweet cherry (Prunus avium L. Hongdeng) trees. 【Result】 Results showed that the development of reproductive organs and the appearances of flower organs were significantly affected by high temperature of 35℃during sprouting period. Earlier high temperature had stronger inhibitory effect on the development of the stamens than on the pistils, leading to brown stamens, even abortive stamen. The florescence was also shortened significantly. As high temperature got close to bud sprouting, the rate of blasted pistil and curled corolla increased, and the first flowering dates were affected more obviously. No exceptional megaspores were found in all high temperature treatments. 【Conclusion】 The results showed that the developing pistil and stamen organs had different sensitive stages and sensitivities to high temperature during the sprouting period.
    STORAGE·FRESH-KEEPING·PROCESSING
    Distribution of Stropharia rugoso–annulata Polysaccharides Molecular Weight and Component Sugar
    CHEN Jun-Chen, WENG Min-Jie, LAI Pu-Fu, LI Yi-Bin, ZHOU Xue-Hua, SHEN Heng-Sheng
    Scientia Agricultura Sinica. 2011, 44(10):  2109-2117.  doi:10.3864/j.issn.0578-1752.2011.10.016
    Abstract ( 573 )   PDF (629KB) ( 749 )   Save
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    【Objective】The aim of this paper was to extract and isolate Stropharia rugoso-annulata polysaccharides and analyze the molecular weight and component sugar of polysaccharides.【Method】In this paper, polysaccharide from Stropharia rugoso-annulata was obtained by water extraction method, which the molecular weight distribution and changes during extraction course was investigated by using high performance liquid chromatography. The component sugar of the polysaccharides were also measured by infrared spectrum and nuclear magnetic resonance methods. 【Result】The molecular weight distribution of water soluble polysaccharides from Stropharia rugoso-annulata was about 22 kD, α and β glucosidic bonds were co-exist in polysaccharides molecule which contain 5 kinds of monosaccharides. The main monosaccharide was pyranose. D-fructose, D-glucose and D-xylose exist in polysaccharides molecule. 【Conclusion】 The detection method with hydrochloric acid solution as the mobile phase can reflect more real molecular weight distribution of polysaccharide from Stropharia rugoso-annulata, and Stropharia rugoso-annulata polysaccharide is a heterosaccharide which is composed of five monosaccharides.
    The Flavor Contribution of Subcutaneous and Intramuscular Fat to Pork
    HUANG Ye-Chuan, HE Zhi-Fei, LI Hong-Jun, QIN Gang, WANG Ting, MA Ming-Hui
    Scientia Agricultura Sinica. 2011, 44(10):  2118-2130.  doi:10.3864/j.issn.0578-1752.2011.10.017
    Abstract ( 900 )   PDF (484KB) ( 948 )   Save
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    【Objective】The objective of this study was to investigate the flavor contribution of subcutaneous and intramuscular fat to pork and provide a scientific basis for improvement of pork products flavor. 【Method】 Different proportions or kinds of subcutaneous fat was added to lean pork, and intramuscular or subcutaneous fat was added to the pork in which the total intramuscular fat had been removed, after cooking, the flavor of above samples was determined by GC-MS and electronic nose. 【Result】 Except the peak area of part of compounds changed to some extent, adding different proportions or kinds of subcutaneous fat to lean pork had no effect on the kinds of volatile flavor compounds in cooked samples. The electronic nose and Partial Least Squares Regression (PLSR) analysis showed that adding different proportions or kinds of subcutaneous fat to lean pork did not result in much change in whole flavor of cooked samples. When 5% subcutaneous fat was added to defatted pork, the kinds of aldehydes and ketones were significantly increased, and the total peak area of the cooked samples was increased by 50%; when 5% intramuscular fat was added, the kinds of aldehydes and ketones were also significantly increased, and the total peak area of the cooked samples was increased by 150%, while the kinds of nitrogen containing compounds were significantly reduced. The electronic nose and PLSR analysis showed that adding subcutaneous fat to defatted pork had little effect on the whole flavor of the cooked samples, but when intramuscular fat was added a remarkable difference was observed. 【Conclusion】 Intramuscular fat contributes significantly to pork flavor while the role of subcutaneous fat is very limited.
    ANIMAL SCIENCE·RESOURCE INSECT
    QTL Mapping for Drip Loss in a White Duroc × Erhualian F2 Resource Population
    ZHOU Li-Hua, GUO Yuan-Mei, DUAN Yan-Yu, ZHANG Zhi-Yan, YANG Kai-Xuan, MA Jun-Wu
    Scientia Agricultura Sinica. 2011, 44(10):  2131-2138.  doi:10.3864/j.issn.0578-1752.2011.10.018
    Abstract ( 726 )   PDF (343KB) ( 738 )   Save
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    【Objective】 A genome-wide scanning was performed to detect quantitative trait loci (QTL) for drip loss. 【Method】Using EZ-DripLoss and bag methods, drip loss of longissimus muscle (LM) and semimembranous muscle (SM) were measured at 24 and 48 h after sampling in 884 F2 animals from a White Duroc×Erhualian resource population. The correlations among 6 drip loss traits and between drip loss and other meat quality traits were analyzed by SAS version 9. All pigs in this experimental population were genotyped for 194 informative markers covering the entire porcine genome. QTL were identified by regression interval mapping using the online software of QTL Express. 【Result】 Correlation between the drip loss of two muscles or between drip loss obtained by two methods were high (r= 0.50-0.58, P<0.01) , and the correlation between consecutive measurements was higher (r=0.59-0.72, P<0.01). Drip loss was correlated with pH24h, Minolta L, subjective color score, marbling, moisture content and intramuscular fat content at moderate or low levels (r=0.09-0.35, P<0.05). A total of 9 QTLs were identified, including 6 QTLs for drip loss of LM on SSC2, SSC10 and SSC12; the one on SSC10 reached the 5% genome-wide significant level. Three QTLs for drip loss of SM were detected on SSC2, SSC6 and SSC17. 【Conclusion】 Four novel QTL on SSC6, SSC10, SSC12 and SSC17 were identified. Several QTL for drip loss overlapped with previously mapped QTL for pH or intramuscular fat content. None of QTL affected drip loss of both LM and SM. Erhualian founders carried favorable alleles (decreasing drip loss) at most of the detected QTL.
    17beta-Estradiol Regulates the Expression of CyclinA2 mRNA of Cultured Immature Boar Sertoli Cells via Estrogen Receptor beta, cAMP-PKA and ERK1/2
    ZUO Jing, GAN Rui, ZHANG Guo-Sheng, ZHANG Jiao-Jiao, ZHU Feng-Wei, SUN Yan, WANG Xian-Zhong, ZHANG Jia-Hua
    Scientia Agricultura Sinica. 2011, 44(10):  2139-2145.  doi:10.3864/j.issn.0578-1752.2011.10.019
    Abstract ( 764 )   PDF (382KB) ( 417 )   Save
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    【Objective】 The objective of this study was to identify whether 17beta-estradiol regulates the expression of cCyclinA2 mRNA via the estrogen receptor beta (ERbetβa) and the cAMP-PKA-extracellular signal-regulated kinase (ERK1/2) pathway. 【Method】Cultured immature boar sertoli cells were treated with 10-9 mol•L-1 17beta-estradiol, and real-time PCR was used to detect the expression of cyclinA2 mRNA.【Result】Treatment with 17beta-estradiol increased the expression of cyclinA2 mRNA from 15 min to 90 min (P<0.05). The effects of 17beta-estradiol activity peaked at 30 min compared to the control cells (P<0.05). Combined treatment with ICI182780 and ERβ reduced the 17beta-estradiol-induced increase in the expression of cyclinA2 mRNA (P<0.05), but ERβ alone did not significantly affect these parameters (P<0.05). Both 17beta-estradiol and forskolin induced the abundance of cyclinA2 mRNA (P<0.05 for both). Combined treatment with Rp-cAMP, H-89 and U0126 reduced the 17beta -estradiol-induced expression of cyclinA2 mRNA (P<0.05 for all), but Rp-cAMP, H-89 and U0126 alone had no significant effect on the abundance of cyclinA2 mRNA, compared to the control group.【Conclusion】 This study showed that 17beta-estradiol regulates the expression of cyclinA2 mRNA via the activation of ERβ, cAMP-PKA and ERK1/2.
    Polymorphisms of the DQA1 Gene in Tibetan Sheep
    CHENG Shu-Ru, LUO Yu-Zhu, HU Jiang, WANG Ji-Qing, LIU Xiu
    Scientia Agricultura Sinica. 2011, 44(10):  2146-2153.  doi:10.3864/j.issn.0578-1752.2011.10.020
    Abstract ( 704 )   PDF (561KB) ( 466 )   Save
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    【Objective】 The Tibetan sheep DQA1 gene polymorphism, determine its allele number, nucleotide polymorphism sites, amino acid polymorphism sites, the genetic relationship and evolutionary significance of the alleles were studied. 【Method】Variation of DQA1 gene in the 900 Tibetan sheep was investigated by amplification of exon 2 using PCR, followed by single-strand conformational polymorphism (SSCP) analysis, cloning, DNA sequencing and sequence data analysis. 【Result】Seventeen alleles were identified including a null allele at the DQA1 locus. Another five alleles were found in the DQA1 gene in this study. Fifty-six nucleotide polymorphism sites and 27 amino acid polymorphism sites were identified in 16 sheep DQA1 gene haplotypes. 【Conclusion】The study indicated that a high level of sequence polymorphism existed in Tibetan sheep DQA1 gene, the population may have more genetic resources. Tibetan sheep DQA1 gene may be differentiated into two major categories alleles from two mutant alleles at first. DQA1 gene in Tibetan sheep and cattle has high homology, which indicated that DQA1 gene in sheep and cattle may come from primordial sequences that were present in a common ancestor and have persisted in the sheep and cattle populations since their divergence, and the observation showed that sheep and cattle share similar allelic sequences may be evidence of the need for a specific immune response to a common pathogen. A new nucleotide mutation (A/G) was discovered in 139 site of new alleles C, and it is the synonymous mutation. Five new alleles have near genetic relationship, they maybe came from the same allele by mutantion.
    Effect of Royal Jelly on Growth and Reproduction Performance of Male Rabbits
    XU Bao-Hua, LIU Zhi-Yong, ZENG Zhi-Jiang
    Scientia Agricultura Sinica. 2011, 44(10):  2154-2160.  doi:10.3864/j.issn.0578-1752.2011.10.021
    Abstract ( 794 )   PDF (368KB) ( 524 )   Save
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    【Objective】 The mechanism of royal jelly in improvement of reproduction performance of animals was explored in this study. 【Method】 Male Japanese white rabbits at the age of 2 months were intragastricaly administrated daily with royal jelly(RJ) at 0.2% and 0.1% of body weight in the high and low dosage group, respectively. Saline water was intragastricaly administrated at 0.1% of body weight in the control group. Rabbits were slaughtered after 80 days, and the body weight of rabbits,the main organ coefficients were calculated. The right testicle of each rabbit was used for morphological analysis after paraffin section preparation. Moreover, the density, motility and deformity rate of sperms were determined in each animal. 【Result】 During the testing period of 0-8 weeks, no significant difference was detected in the body weight of rabbits among the 3 groups (P>0.05). However, the body weight was significantly greater in the treatment groups than the control group after 9-weeks treatment (0.01<P≤0.05). The organ coefficients of testicular, hypothalamus and spleen were significantly different between the treatment and control group (P≤0.01). And no difference was found in the organ coefficients of spleen, lung, heart, liver, kidney and urinary bladder among the 3 groups (P>0.05). The sperm density in RJ treatment groups was significantly higher than that in control group(P≤0.01). The semen motility of rabbits in the low dosage group was significantly higher than control group (P≤0.01), and the control group was significantly higher than the high dosage group (P≤0.01). After 80-days of RJ treatment, the spermatogenic epithelium cells of convoluted seminiferous tubules in testicular of male rabbit was significantly less, spermatogenic epithelium was fewer and scattered in the control group. Moreover, most of them contained in the center hole was primary and second apermatocytes. In comparison, the space of convoluted seminiferous tubules was less in the RJ treatment group because of sertolis cells and spermatozoa. Spermatogonia were affiliated on the basement membrane, the primary spermatocytes, spermatids, and spermatozoa were extended tightly into the center hole. The core was dying clearly, and most of containing in the center hole were spermatozoas. 【Conclusions】RJ intragastric administration can promote the development of male reproductive organs, like hypothalamus and testicular. And intragastirc administration with RJ at 0.1% of body weight can improve the motility and density of sperm in rabbits.
    VETERINARY SCIENCE
    Establishment of Experimental Infection Model of Duck Hemorrhagic Ovaritis
    LIN Jian, HAN Chun-Hua, CHEN Hua-Lin, JIANG Tao-Zhen, LIANG Wu, HE Ping-You, YANG Bao-Shou, WANG Ying, HAN Jing-Wen, LIU Dong-Yan, PAN Jie, DUAN Hui-Juan, DING Pei-Pei, HU Sheng-Qiang, LIU Yue-Huan
    Scientia Agricultura Sinica. 2011, 44(10):  2161-2167.  doi:10.3864/j.issn.0578-1752.2011.10.022
    Abstract ( 623 )   PDF (492KB) ( 775 )   Save
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    【Objective】 The objective of the study is to create an experimental infection model of Duck Hemorrhagic Ovaritis, study the disease characterization and provide an available model for developing vaccine and evaluating antiviral medicine.【Method】 The infected 196-day-old ducks were inoculated with 104 ELD50 of a DHOV isolate, DHOV-HB-F4, via a combination of intranasal, intraoral and intraocular inoculation method. Clinical signs were observed and recorded daily. At 5, 7, 9, 21, 28 and 34 day after inoculation, serum samples were taken, randomly selected and sacrificed for necropsy. Gross lesions were recorded and various tissues were collected for histological examination. Various tissues including ovaries, liver, brain, and spleen were collected for re-isolating virus. The method of fixed virus and diluted sera was used to detect the neutralizing antibody.【Result】The food consumption of infected ducks showed significant decrease (decreased by 80%) at 3, 4, 5 day post inoculation (DPI), recovered to 50% of normal intake at 6 DPI and to normal level at 11DPI. The egg production of infected ducks was significantly decreased at 3, 4, 5 DPI and zero at 6, 7, 8 DPI. The laying rate of infected ducks recovered to 60% of normal at 36 DPI and 80% at 39 DPI. DHO virus could be successfully re-isolated from three ducks’ ovaries and liver on 5 DPI (3/3), two ducks’ ovaries (2/2) and one duck’s spleen and brain(1/2) on 7 DPI, one duck’s ovaries(1/2) on 9 DPI. At 21 and 28 DPI, DHO virus could not be re-isolated from the infected ducks’ tissues. The infected ducks showed ovary degeneration and deformation, follicle membrane hyperaemia and haemorrhagia; ovary, liver, brain and spleen characterized by the reticular cells hyperplasia which showed acute Hemorrhagic Ovaritis, interstitial hepatitis, nonpurulent meningoencephalitis, necrotizing splenitis, interstitial nephritis and mild myocarditis. The infected ducks only produced lower-titer neutralizing antibody on week 3 post inoculation.【Conclusion】The experimental ducks showed acute Hemorrhagic Ovaritis after infected by Duck Hemorrhagic Ovaritis. The experimental infection model of Duck Hemorrhagic Ovaritis was developed in Peking duck which could be a model for screening and evaluating the antiviral medicine and vaccine.
    Progress in Research of Animal Transgenic Technology
    CHEN Qing, CAO Wen-Guang
    Scientia Agricultura Sinica. 2011, 44(10):  2168-2175.  doi:10.3864/j.issn.0578-1752.2011.10.023
    Abstract ( 591 )   PDF (724KB) ( 955 )   Save
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    Animal transgenic technology refers to the transfer of an exogenous gene into animal genome by random or site-specific integration and the foreign gene can be expressed and inherited to the offspring. Various technologies in animal transgenesis have now been widely applied to areas such as animal husbandry, medical industry, environmental protection and new biological materials production. This article reviews the recently developed technologies based on lentivectors, spermatogonial stem cells, zinc finger nucleases and RNA interference.
    RESEARCH NOTES
    Effects of All Straw Returned to the Field on Grain Number and Grain Weight at Different Spikelets and Grain Positions in Winter Wheat
    QU Hui-Juan, LI Jin-Cai, SHEN Xue-Shan, WEI Feng-Zhen, WU Jin-Dong, MA Bei
    Scientia Agricultura Sinica. 2011, 44(10):  2176-2183.  doi:10.3864/j.issn.0578-1752.2011.10.024
    Abstract ( 534 )   PDF (433KB) ( 551 )   Save
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    【Objective】 The objectives of this study were to research the change of gain number and grain weight of wheat with spikelet and grain position in main stem and tiller spike under the condition of straw returned to the field. 【Method】 A location field experiment was conducted from 2008 to 2010, single maize straw returned to the field, single wheat straw returned to the field, wheat and maize straw returned to the field were conducted to study the effects of straw returned to the field on grain number and grain weight at different spikelets and grain positions in winter wheat. 【Result】Results showed that, the spike per hectare, grain number per spike, 1 000-grain weight and yield were increased in treatment of straw returned to the field. The distribution of grain number, spikelet weight, and grain weight with the spikelets positions showed parabolic changes, so as the grain weight at 1st, 2nd, 3rd in each treatment and 4th in treatment of straw returned to the field. The more fertile spikelet number and less difference in spikelet grain number and single grain weight, the smoother the parabola was. The fertile spikelet number and spikelet grain number in main stem and tiller spike were increased in treatment of straw returned to the field, the increase range of fertile spikelet number in the bottom spikelet were bigger. There were different increasing effects of straw returned to the field on single grain weight at different grain positions, especially for at of 3rd and 4th grain position. 【Conclusion】 Therefore, under the condition of wheat and maize straw returned to the field, grain yield and yield components, spikelet grain number and grain weight at different spikelets of wheat were enbanced.
    Effects of Exogenous Nitric Oxide on Physiological Characteristics of Seedlings of Malus hupehensis Rehd. Under Continuous Cropping
    GAO An-Ni, TIAN Chang-Ping, HU Yan-Li, CHEN Qiang, MAO Zhi-Quan
    Scientia Agricultura Sinica. 2011, 44(10):  2184-2192.  doi:10.3864/j.issn.0578-1752.2011.10.025
    Abstract ( 628 )   PDF (403KB) ( 461 )   Save
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    【Objective】 Effects of exogenous nitric oxide on the growth, root architecture, soil environment, activities of protective enzymes and oxidative damage of seedlings of Malus hupehensis Rehd. under continuous cropping were investigated. The action mechanisms of nitric oxide were explored so as to provide a theoretical basis for alleviating apple continuous cropping. 【Method】 Sodium nitropprusside (SNP, an exogenous nitric oxide donor) at concentrations of 0-1 000 μmol•L-1 were added to the containers, the plant height, leaf area, root volume, number of tips, quantity of major microorganism groups, phenolic compounds and the activities of protective enzymes (including SOD, POD, CAT and APX) in leaves, malondialdehyde (MDA) content , and   producing rate in leaves were investigated. 【Result】 The above results indicated that the best alleviating effect was 200 μmol•L-1 SNP. At this concentration, the plant height, fresh weight, chlorophyll content and leaf area were significantly increased, comparing with contrast one, increased by 59.69%, 74.25%, 45.70%, 116.58%, respectively. The parameters of root architecture, such as average diameter, total root volume and number of tips were significantly increased. The activities of SOD, POD, CAT and APX were higher significantly than untreated seedlings, while malondialdehyde (MDA) content and   producing rate were lower significantly than untreated seedlings. Exogenous nitric oxide had little effect on the quantity of major microorganism groups (bacteria, fungi and actinomycete) and phenolic compounds in rhizosphere soil. 【Conclusion】 The above results indicated that exogenous nitric oxide had an effective function on the alleviation of continuous cropping obstacle in seedlings of Malus hupehensis Rehd. Exogenous nitric oxide had some influence on the biological factors and abiotic factors, but both of them were not the main reasons for alleviating continuous cropping obstacle in seedlings of Malus hupehensis Rehd. The activities of SOD, POD, CAT were improved obviously, while malondialdehyde (MDA) content and   producing rate were decreased significantly, which were two kinds of important reasons.