Grain yield in cereal crops was an eternal theme.The number of panicles perplant(PN),filled spikelets per panicle(FSP),and 1000-grain weight(TGW)were the three important yield components.Some QTLs for rice yield had b...Grain yield in cereal crops was an eternal theme.The number of panicles perplant(PN),filled spikelets per panicle(FSP),and 1000-grain weight(TGW)were the three important yield components.Some QTLs for rice yield had beenmapped,but conditional QTLs for grain yield had not been analyzed.Phenotypicvalues of yield traits,which had no influence on the given components,wereused for QTLs conditional analysis.This study was to uncover conditional QTLsfor rice yield in a RIL population,and to search for evidences on the geneticbasis of yield QTLs.展开更多
A continuum model of solids with cylindrical microvoids is proposed based on the Taylor dislocation model. The model is an extension of Gurson model in the sense that the void size effect is accounted for. Beside the ...A continuum model of solids with cylindrical microvoids is proposed based on the Taylor dislocation model. The model is an extension of Gurson model in the sense that the void size effect is accounted for. Beside the void volume fraction f, the intrinsic material length l becomes a parameter representing voids since the void size comes into play in the Gurson model. Approximate yield functions in analytic forms are suggested for both solids with cylindrical microvoids and with spherical microvoids. The application to uniaxial tension curves shows a precise agreement between the approximate analytic yield function and the exact parametric form of integrals.展开更多
Based on grain yield data of China, the vanation features of grain yield in China in recent 40 years and their relationships with the associated factors were analyzed. Results show that the total grain yield increased...Based on grain yield data of China, the vanation features of grain yield in China in recent 40 years and their relationships with the associated factors were analyzed. Results show that the total grain yield increased gradually, and its interannual variation is influenced principally by unit area crop yield (about 70 percent in average). The influences of agricultural technology, social factors and weather conditions on thet area crop yield can be separated because of their unique variation trends and time scales. The influence of agricultural technology is in a smoothly and gradually incremental trend, and the influence of the social factors is oscillated with three waves in recent 40 years, and the influence of weather conditions is fiuctuated sharply from year to year. Their mean effects on the inter-annual variation of unit area crop yield are about 35 to 40 percent, 10 to 15 percent and 50 percent respectively. In the view point of predictions, the effects of weather conditions are much more important.展开更多
文摘Grain yield in cereal crops was an eternal theme.The number of panicles perplant(PN),filled spikelets per panicle(FSP),and 1000-grain weight(TGW)were the three important yield components.Some QTLs for rice yield had beenmapped,but conditional QTLs for grain yield had not been analyzed.Phenotypicvalues of yield traits,which had no influence on the given components,wereused for QTLs conditional analysis.This study was to uncover conditional QTLsfor rice yield in a RIL population,and to search for evidences on the geneticbasis of yield QTLs.
基金The project supported by the National Natural Science Foundation of China(20020003023)the Ministry of Education(key grant 0306)
文摘A continuum model of solids with cylindrical microvoids is proposed based on the Taylor dislocation model. The model is an extension of Gurson model in the sense that the void size effect is accounted for. Beside the void volume fraction f, the intrinsic material length l becomes a parameter representing voids since the void size comes into play in the Gurson model. Approximate yield functions in analytic forms are suggested for both solids with cylindrical microvoids and with spherical microvoids. The application to uniaxial tension curves shows a precise agreement between the approximate analytic yield function and the exact parametric form of integrals.
文摘Based on grain yield data of China, the vanation features of grain yield in China in recent 40 years and their relationships with the associated factors were analyzed. Results show that the total grain yield increased gradually, and its interannual variation is influenced principally by unit area crop yield (about 70 percent in average). The influences of agricultural technology, social factors and weather conditions on thet area crop yield can be separated because of their unique variation trends and time scales. The influence of agricultural technology is in a smoothly and gradually incremental trend, and the influence of the social factors is oscillated with three waves in recent 40 years, and the influence of weather conditions is fiuctuated sharply from year to year. Their mean effects on the inter-annual variation of unit area crop yield are about 35 to 40 percent, 10 to 15 percent and 50 percent respectively. In the view point of predictions, the effects of weather conditions are much more important.
