不同穗型超高产小麦旗叶CO_2同化能力的比较

Comparison of CO_2 Assimilation Capacity in Flag Leaf for Super-high-yield Wheat with Different Spike Type

在超高产条件下 ,对多穗型小麦品种豫麦 4 9和大穗型品种周麦 13旗叶净光合速率 (Pn)、RuBP羧化酶 (RuBP case)活性、羧化效率 (CE)及Pn 对CO2 的响应进行了研究。结果表明 ,两品种旗叶一生Pn、RuBPcase活性变化趋势一致 ,各处理旗叶展开后Pn 和RuBPcase活性逐渐上升 ,于展开后第 10天达最大值 ,之后逐渐下降。两品种相比 ,旗叶展开的0～ 10d内豫麦 4 9各处理的Pn、RuBPcase活性、CE均高于周麦 13,而第 2 0天以后周麦 13则高于豫麦 4 9。豫麦 4 9CO2 饱和点低于周麦 13,而其CO2 补偿点则高于周麦 13。两品种B2 处理 (基本苗 15 0× 10 4株·hm-2 )旗叶表现出明显的CO2 同化优势。

The responses of net photosynthesis rate ( P n),RuBPcase activity and carboxylation efficiency (CE) in flag leaf for two cultivars,Yumai 49,a small spike type,and Zhoumai 13,a large spike type,to CO 2 concentration were studied in super-high-yield condition. The P n and RuBPcase activity increased gradually in the initial 10 days and reached the maximum value at the 10 th day,then declined gradually for both the cultivars after flag leaf fully expanded. Compared with Zhoumai 13,Yumai 49 had higher P n,RuBPcase activity and CE in 0-10 days after flag leaf fully expanded,and vice versa after the 20 th day. Yumai 49 had lower CO 2 saturation point but higher CO 2 compensation point than that of Zhoumai 13. We came to the conclusion that Zhoumai 13 had higher CO 2 assimilation capacity than Yumai 49. The B 2 treatment(base plant of 150×10 4 plant·ha)of the two cultivars had apparent advantages in CO 2 assimilation capacity.