At all stage of flag leaves senescence, we can find the activity of C_4 pathway enzymes:PEPCase,PPDK,NADP-ME,NADP-MDH. We surmise that there are C_4 path-way in hybrid rices.

• 本实验亦证明在剑叶全展后的各时期均能测定到C_4途径关键酶:PEPCase、PPDK、NADP-ME和NADP-MDH的活性,推测在供试材料中可能存在有C_4途径。