不同栽培模式早稻-再生稻的能量积累与热值分析

以杂交水稻新组合Ⅱ优航1号为材料探讨了超高产栽培和常规栽培模式下早稻-再生稻的干物质积累以及热值和能量固定特征。结果表明，超高产模式头季稻完熟期干物质积累量为2 220.04 g m^-2，是常规模式的1.26倍，再生稻为1 697.62 g m^-2，是常规模式的1.29倍。超高产模式下的热值，叶为14 848.7~18 494.9 J g^-1，籽粒为15 810.3~17 438.0 J g^-1，鞘为14 029.1~17 039.6 J g^-1，茎为14 405.4~17 576.5 J g^-1，叶和籽粒的热值显著高于茎、鞘，各器官及稻株的热值在不同栽培模式间无显著差异。在完熟期，超高产模式头季稻、再生稻的能量积累量分别为35.71 MJ m^-2和26.24 MJ m^-2，依次比常规模式高出27.4%和29.6%；籽粒能量分配比例头季稻为52.7%，比常规模式高1.2%，再生稻均为51.5%，不同栽培模式间无显著差异。灌浆过程中，超高产模式头季稻叶、茎、鞘的总能量表观转化率为39.7%，显著高于常规模式(23.1%)，再生稻的叶、茎、鞘的总能量表观转化率为16.9%，也高于常规模式(14.7%)，超高产模式下水稻群体能流更顺畅。同时，超高产模式头季稻黄熟过程根系的能量输出为7.9%，远低于常规模式(78.2%)，保证头季稻灌浆和再生稻萌发的顺利进行；超高产模式再生稻籽粒贮能表观上25.9%来自稻桩的再转运，对后期光合的依赖比较小，保证了再生稻的稳产和高产。

Analysis on Energy Accumulation and Calorific Value of Early-Season Rice and Its Ratooning Rice under Different Cultivation Models

A new hybrid rice Ⅱ Youhang 1 was used to analyze accumulated dry weight, energy fixation and calorific value in early-season rice and its ratooning rice under super high-yield cultivation (SHC) and conventional cultivation (CC) models. The results showed that accumulated dry weight in the plants at mature stage under SHC was 2 220.04 g m^-2 and 1 697.62 g m^-2 for early- season and ratooning rice, respectively, being 1.26 and 1.29 folds higher than that under CC. Calorific value in leaf, grain, sheath and culm of the plant was 14 848.7–18 494.9 J g^-1, 15 810.3–17 438.0 J g^-1, 14 029.1–17 039.6 J g^-1, 14 405.4–17 576.5 J g^-1 under SHC, respectively. The calorific values in leaf and grain were significantly higher than those in culm and sheath, but no significant difference was found under the two cultivation models. The accumulated energy in the plants at mature stage was 35.71 and 26.24 MJ m^-2 under SHC for early season and ratooning rice, respectively, being 27.4% and 29.6% higher than that under CC. The ratio of accumulated energy partitioned into grains was 52.7% for early-season rice under SHC, which was 1.2% higher than that under CC, and for ratooning rice (51.5%), there was no significant difference between the two models. During grain filling, the ratio of energy remobilized from leaf, culm and sheath was 39.7% for early- season rice under SHC, being significantly higher than that under CC (23.1%), and the value was 16.9% for ratooning rice, which was also higher than that under CC (14.7%). It implied that the energy flow in rice community under SHC was much more smoothly than that under CC. In addition, at yellow mature stage, the energy exportation ratio of root was 7.9% under SHC, being obviously lower than that of CC, it was ensured for grain filling and regeneration of ratooning rice, and the energy of grains remobilized from the stubble of ratooning rice was 25.9% apparently, indicating that the grain yield under SHC relied less on the photosynthate in the period of grain filling, which was beneficial to steady and high yield of ratooning rice.