贵州高原粳稻净光合和光呼吸速率与干物重关系

Relationship Between net Photosynthetic Rate Photorespiratory Rate and Dry-matter Weight of Local Keng Rice in Guizhou

贵州高原粳稻抽穗期剑叶净光合速率(P_n)的平均值、变幅与矮秆粳稻差异很小,但存在显著的品种差异;光呼吸速率(P_r)的平均值此矮秆粳稻高,但品种间变幅、变异系数却较矮秆粳稻低。在抽穗期和灌浆期,高原粳稻不同叶位的P_n值均以剑叶为最高,随叶位下降而下降。灌浆期下位叶P_n值的下降更为显著,且不同品种下降徒度不同。抽穗期高原粳剑叶与倒二叶的P_r平均值差异不大,但不同品种表现各异。高原粳的P_r值随叶位降低而下降。高原粳的单株干物重以分蘖期到抽穗期增加最快。抽穗后15天单株干物重反而减少。而同期矮杆粳则仍有所增加。高原粳稻各生育期的单株干重与活动中心叶P_n·P_r值均未达到显著平准。

The net photosythetic rase (P_n), photorespiratory rate (P_r) and dry—matter weight of local keng rice in Guizhou were measured in 1986-1987. The results indicated that there is not significant difference beween P_n of flag leaf from local keng rice and dwarf keng rice but the coefficient of variation was lower in the former. There is significant difference among P_n form different varieties of local keng rice. P_r of flag leaf from local keng rice is higher than that of dwarf keng rice at heading stage but the coefficient of variation is lower. There were considerable variabilitier for the ratio of flagleaf P_n to lower lives P_n at heading stage and milky stage in different varietes of local keng rice. It is useful for breeding for higher P_n of lower leares after heading P_r of flag leaf is close to that of lower leares after heading in local keng rice. For dwarf keng rice, the flag leaf has a hiher P_r than lower leavas.Dry-matter weight per plant of local keng rice increases fast from tillering stage to heading stage. Howerer, it decveased after heading stage. At to the relationship between two rate (P_n and P_r ) and dry-matter weight, significant correlation is not found in local keng rice.