在盆栽条件下 ,利用氮肥和改变源库比的方法 ,研究了籽粒形成期 2个冬小麦品种的 14 CO2 同化及同化物的分配特征。结果表明 ,莱州 953的 CO2 同化能力显著高于鲁麦 14 ,但后者 14 C光合产物向籽粒中的分配比例较高 ,茎叶中残留比例较小。去穗 1/ 3以减少籽粒库容后 ,莱州 953的 14 C同化受影响较小 ,而鲁麦 14的 14 CO2 同化量则显著上升。开花期增施氮素能继续提高莱州 953的 CO2 同化能力 ,但不能有效地增加鲁麦14 CO2 同化能力。14 C同化及其调节特征的品种间差异 ,应在栽培措施上有所考虑 Under potted condition, 14 CO2 assimilation and assimilate assimilation characteristics of two winter wheat cultivars were studied by using nitrogen fertilizer and changing source-sink ratio. The results showed that the CO2 assimilation capacity of Laizhou 953 was significantly higher than that of Lumai 14, but the 14 C photosynthate of the latter had a higher distribution proportion to kernels and a smaller residual ratio in stems and leaves. 14 C assimilation of Laizhou 953 was less affected by spike 1/3 to reduce grain storage, whereas 14 C02 assimilation of Lumai 14 was significantly increased. Nitrogen application in flowering stage can continue to increase CO2 assimilation capacity of Laizhou 953, but it can not effectively increase CO2 assimilation capacity of Lumai 14. Differences among 14 C assimilation and its regulatory traits should be considered in cultivation measures