实现粮食的持续稳定增长是保障区域粮食安全的关键。分解各因素对粮食生产的作用及影响强度,识别其主导因素,对提升粮食产量具有积极意义。该文运用对数平均迪氏分解方法(logarithmic mean weigh division index method,LMDI)建立因素...实现粮食的持续稳定增长是保障区域粮食安全的关键。分解各因素对粮食生产的作用及影响强度,识别其主导因素,对提升粮食产量具有积极意义。该文运用对数平均迪氏分解方法(logarithmic mean weigh division index method,LMDI)建立因素分解模型,定量评价并对比分析1980-2010年间黄淮海地区县域粮食生产变动的区域因素。结果表明,1)1980-2010年间,黄淮海地区粮食产量增加了1.01亿t,县域粮食产量"南高北低"的空间分异格局明显,苏北、皖北、豫东和鲁西地区的粮食增产显著;2)4个因素中,粮食单产对粮食产量变化起到显著的正向促进作用,复种指数次之,而粮作比例和耕地面积在较大程度上抑制了黄淮海地区粮食产量的增加;3)县域粮食生产因素分解结果表明,县域之间在耕地面积、复种指数、粮作比例和粮食单产效应方面存在明显差异。总体而言,粮食单产效应叠加上复种指数效应使苏北、皖北和豫东多数县域粮食总产量显著增加;而粮作比例效应、复种指数效应和粮食单产效应的叠加使鲁西县域的粮食总产量增加明显。展开更多
A mathematical model based on the theory of heat and mass transfer in porous media was developed to simulate the evolution of grain temperature and moisture content in a wheat storage bin during ventilation with cooli...A mathematical model based on the theory of heat and mass transfer in porous media was developed to simulate the evolution of grain temperature and moisture content in a wheat storage bin during ventilation with cooling air at the constant temperature and humidity.Unlike the previous works on this aspect,the present work was not focused on cooling the stored grain by ventilation with ambient air,but with the refrigerated air.Validation was performed by comparing between predicted and measured grain temperature and grain moisture content for two cases.Predicted data were in reasonable good agreement with measured ones.The model and the parameter values used in the model are applicable for predicting temperature and moisture of stored grains under ventilation conditions.展开更多
High chalkiness is a major problem in many rice-producing areas of the world, especially in hybrid rice （Oryza sativa L.） in China. We previously showed a major quantitative trait locus for the percentage of grains ...High chalkiness is a major problem in many rice-producing areas of the world, especially in hybrid rice （Oryza sativa L.） in China. We previously showed a major quantitative trait locus for the percentage of grains with white chalkiness （QTLqPGWC-8） in the interval G1149-R727 on chromosome 8 using a chromosome segment substitution line （CSSL）. Here, we selected the line-CSSL50 harboring the QTLqPGWC-8 allele from the CSSLs derived from a cross between Asominori （as a recurrent parent） and IR24 （as a donor parent）, which had higher percentage chalkiness, markedly different from that of Asominori. There were also significant differences in starch granules, appearance of amylose content （AAC） and milling qualities between Asominori and CSSL50, but not in grain size or thousand grain weight （TGW）. The BC4F2 and BC4F3 populations from a cross between CSSL50 and Asominori were used for fine mapping of qPGWC-8. We narrowed down the location of this QTL to a 142 kb region between Indel markers 8G-7 and 8G-9. QTLqPGWC-8 accounted for 50.9% of the difference in PGWC between the parents. The markers tightly linked to qPGWC-8 should facilitate cloning of the gene underlying this QTL and will be of value for marker-assisted selection in breeding rice varieties with better grain quality.展开更多
文摘实现粮食的持续稳定增长是保障区域粮食安全的关键。分解各因素对粮食生产的作用及影响强度,识别其主导因素,对提升粮食产量具有积极意义。该文运用对数平均迪氏分解方法(logarithmic mean weigh division index method,LMDI)建立因素分解模型,定量评价并对比分析1980-2010年间黄淮海地区县域粮食生产变动的区域因素。结果表明,1)1980-2010年间,黄淮海地区粮食产量增加了1.01亿t,县域粮食产量"南高北低"的空间分异格局明显,苏北、皖北、豫东和鲁西地区的粮食增产显著;2)4个因素中,粮食单产对粮食产量变化起到显著的正向促进作用,复种指数次之,而粮作比例和耕地面积在较大程度上抑制了黄淮海地区粮食产量的增加;3)县域粮食生产因素分解结果表明,县域之间在耕地面积、复种指数、粮作比例和粮食单产效应方面存在明显差异。总体而言,粮食单产效应叠加上复种指数效应使苏北、皖北和豫东多数县域粮食总产量显著增加;而粮作比例效应、复种指数效应和粮食单产效应的叠加使鲁西县域的粮食总产量增加明显。
文摘A mathematical model based on the theory of heat and mass transfer in porous media was developed to simulate the evolution of grain temperature and moisture content in a wheat storage bin during ventilation with cooling air at the constant temperature and humidity.Unlike the previous works on this aspect,the present work was not focused on cooling the stored grain by ventilation with ambient air,but with the refrigerated air.Validation was performed by comparing between predicted and measured grain temperature and grain moisture content for two cases.Predicted data were in reasonable good agreement with measured ones.The model and the parameter values used in the model are applicable for predicting temperature and moisture of stored grains under ventilation conditions.
基金supported by the National Natural Science Foundation of China(30771325)National Key Transform Program(2008ZX08001-06)+2 种基金the earmarked fund for Modern Agro-industry Technology Research SystemJiangsu Cultivar Development Program(BE2008354 and BE2009301-3)the 111 project
文摘High chalkiness is a major problem in many rice-producing areas of the world, especially in hybrid rice （Oryza sativa L.） in China. We previously showed a major quantitative trait locus for the percentage of grains with white chalkiness （QTLqPGWC-8） in the interval G1149-R727 on chromosome 8 using a chromosome segment substitution line （CSSL）. Here, we selected the line-CSSL50 harboring the QTLqPGWC-8 allele from the CSSLs derived from a cross between Asominori （as a recurrent parent） and IR24 （as a donor parent）, which had higher percentage chalkiness, markedly different from that of Asominori. There were also significant differences in starch granules, appearance of amylose content （AAC） and milling qualities between Asominori and CSSL50, but not in grain size or thousand grain weight （TGW）. The BC4F2 and BC4F3 populations from a cross between CSSL50 and Asominori were used for fine mapping of qPGWC-8. We narrowed down the location of this QTL to a 142 kb region between Indel markers 8G-7 and 8G-9. QTLqPGWC-8 accounted for 50.9% of the difference in PGWC between the parents. The markers tightly linked to qPGWC-8 should facilitate cloning of the gene underlying this QTL and will be of value for marker-assisted selection in breeding rice varieties with better grain quality.
