不同水稻品种产量形成过程的固碳特性研究

 【目的】明确不同水稻品种产量形成过程的固碳特性。【方法】测定三系杂交稻汕优63、二系杂交稻两优2186和常规稻IR64生长过程各器官干物质积累、碳含量。【结果】完熟期，汕优63、两优2186和IR64全株平均碳含量依次为：40.65%、41.81%和40.44%，各器官间碳含量大小为：籽粒＞叶＞茎＞鞘＞根；汕优63、两优2186和IR64的碳积累量均在黄熟期达到最大，分别达到853.68、827.61和810.13g?m-2。完熟期，汕优63、两优2186和IR64的碳积累量下降到773.17 g?m-2，783.65g?m-2和767.94g?m-2，其中分配到籽粒中的比例分别为：53.23%、45.66%和47.83%，同期的释氧量依次为2 061.80g?m-2、2 089.73g?m-2和2 047.84g?m-2，这对维持稻田生态系统的碳氧平衡起到重要作用。汕优63、两优2186和IR64在孕穗初期至齐穗期间的碳净固定量最高，依次为339.60 g?m-2、369.33 g?m-2和309.62 g?m-2，分别占全生育期碳总固定量的43.92%，47.13%和40.31%，是水稻固碳的关键时期。3种水稻在完熟期均出现耗碳吸氧现象，汕优63吸氧量为214.69 g?m-2，分别是两优2186、IR64的1.83倍和1.91倍。【结论】三系杂交稻汕优63在产量形成过程中具有高积累、高消耗碳的特性，其灌浆过程消耗的碳对促进其产量形成具有重要作用。

Characteristics of Carbon Fixation in Different Rice Cultivars During Yield Formation Process

Abstract: Characteristics of carbon fixation, followed by the previous study of dry matter accumulation in three different rice cultivars, Shanyou 63, Liangyou 2186 and IR64, were studied at the experimental farm of Fujian Agriculture and Forestry University, Fuzhou China in 2003. The results showed that the carbon contents of whole plant in the three rice cultivars, were 40.65%、41.81% and 40.44% for Shanyou 63, Liangyou 2186 and IR64 at full mature stage, respectively, and carbon contents in different rice plant parts showed the trends of grain>leaf>stem>sheath>root in order. In addition, the carbon accumulation in the three rice cultivars peaked at yellow mature stage, with a amount of 853.68 g·m-2,827.61 g·m-2 and 810.13 g·m-2 then went down to 773.17 g·m-2, 783.65 g·m-2 and 767.94 g·m-2 at full mature stage, and the amount of released oxygen reached to 2061.80 g·m-2, 2089.73 g·m-2 and 2047.84 g·m-2 in whole growing and developmental stage, which is important for maintaining the balance between CO2 and O2 in the field of rice ecosystem. From early heading stage to full heading stage, the net accumulation of carbon in Shanyou 63, Liangyou 2186 and IR 64 were 339.60 g·m-2, 369.33 g·m-2 and 309.62 g·m-2, and performanced the highest in whole growing and developmental stage, showing 43.92%, 47.13% and 40.31% of total carbon accumulation, which was considered a key stage for carbon fixing of rice. It was also shown that the three rice cultivars cost the carbon accumulated at previous developmental stages to further promote grain filling process, Shanyou 63 consumed oxygen 214.69 g·m-2 at full mature stage, which was 1.83 and 1.91 times as higher as those of Liangyou 2186 and IR64 respectively. The result implied that it appeared to be higher carbon consuming characteristics of Shanyou 63 during grain filling process, but further study is needed to elucidate its mechanism in yield formation.