选取有代表性的12个水稻品种,研究分蘖期和灌浆期不同类型水稻之间光合作用的差异.结果表明:在分蘖期籼稻与粳稻的净光合速率(A)和气孔导度(gs)无显著差异,但常规稻大于杂交稻.粳稻的比叶重(specific leaf weight,SLW)、SPAD和叶片氮素含量(Narea)基本都大于籼稻,但常规稻与杂交稻无显著差异.在灌浆期A和gs基本表现为常规籼稻>杂交籼稻>常规粳稻>杂交粳稻.2种氮肥处理下,常规稻的SPAD和Narea基本大于杂交稻.低氮处理下粳稻的SPAD和Narea大于籼稻,而高氮下籼稻与粳稻无显著差异.光合氮素利用效率(photosynthetic N use efficiency,PNUE)与SLW和非结构性碳水化合物(non-structural carbohydrate,NSC)含量均呈现出显著的负相关关系.因此,gs是造成不同品种之间A存在差异的主要原因,并且SLW、NSC是影响PNUE的主要因素.%Twelve rice cultivars were selected to investigate the varietal differences in photosynthesis at both tillering and grain filling stages.The results show that: 1) At tillering stage, leaf photosynthetic rate (A) and stomatal conductance (gs) show no significant difference between indica and japonica rice plants, but they are higher in inbred than in hybrid plants.Specific leaf weight (SLW), SPAD, and leaf nitrogen content (Narea) are generally higher in japonica than in indica rice plants.2) At grain filling stage, A and gs are the highest in inbred indica rice, followed by hybrid indica, inbred japonica, and then hybrid japonica rice.At both N supplies, inbred rice plants show higher SPAD and Narea than hybrid rice.SPAD and Narea are higher in japonica than in indica riceat low N supply, but there are no significant difference at high N supply.3) Photosynthetic N use efficiency (PNUE) is negatively related to SLW and non-structural carbohydrate (NSC).Therefore, gs is the major reason for the varietal difference in A, and SLW and NSC can significantly affect PNUE.
展开▼
