应用~(14)C示踪研究双季超高产栽培条件下水稻后期功能叶的光合特性

本研究结果表明 :超高产栽培 (VSHM)条件下剑叶和倒 2叶对14 CO2 的净同化强度分别极显著和显著高于对照 ,早稻和晚稻的趋势一致 ,是叶面积较大和单位面积光合速率较高所致。早稻和晚稻在灌浆结实期剑叶和倒 2叶的14 C 同化产物 5d内有1 7 5%～ 2 1 0 %滞留在标记叶内 ,滞留率晚稻大于早稻 ,倒 2叶大于剑叶 ,不同栽培处理之间差异不明显。14 C 的同化物有 45 3 %～ 65 4%向穗部运转 ,早稻大于晚稻 ,剑叶大于倒 2叶 ,VSHM比CK略有提高。VSHM超高产栽培双季实际产量达1 771 0kg hm2 ,比对照提高 1 8 3 3 % ,差异达 5%的显著水平

COMPARISON OF NET PHOTOSYNTHETIC RATE AND ~(14)C DISTRIBUTION BETWEEN DIFFERENT CULTURAL CONDITIONS ON DOUBLE CROPPING RICE

By applying the cultural method“Vigorous Root|Strong Stem|Heavy Panicle Cultural Method”(VSHM),the yield of double cropping rice reached 18000kg/hm+2 in large area at Liling county, Hunan province.The net photosynthetic rate and 14 C distribution of rice leaves between VSHM and traditional cultural methods(CK) were compared.The photosynthetic rate of the flag leaves at ripening stages under VSHM was higher than that of controls with both earlier rice or later rice.Regarding the net amount of 14 C|assimilate by a single flag leaf and the second top leaf,there were differences at the significant level of 0.01 and 0.05,respectively between VSHM and controls,and VSHM were 7.72%～35.05% higher.The percentage of distribution at panicles of 14 C|assimilate were 51.93%～61.40% when flag leaf was labeled,and 45.34%～54.25% when the second top leaf was labeled,that of earlier rice was higher than later rice respectively,but the differences were not significant between VSHM and CK.The actual yield of double cropping rice under the cultural condition of VSHM was 17710kg/hm+2, and increased by 18.33% when compared with controls.