Hasegawa Toshihiro, Sakai Hidemitsu, Tokida Takeshi, Nakamura Hirofumi, Zhu Chunwu, Usui Yasuhiro, Yoshimoto Mayumi, Fukuoka Minehiko, Wakatsuki Hitomi, Katayanagi Nobuko, Matsunami Toshinori, Kaneta Yoshihiro, Sato Takashi, Takakai Fumiaki, Sameshima Ryoji, Okada Masumi, Mae Tadahiko, Makino Amane
National Institute for Agro-Environmental Sciences, Tsukuba, Ibaraki 305-8604, Japan.
Taiyokeiki Co. Ltd, Kita-ku, Tokyo 114-0032, Japan.
Funct Plant Biol. 2013 Mar;40(2):148-159. doi: 10.1071/FP12357.
There is some evidence that rice cultivars respond differently to elevated CO2 concentrations ([CO2]), but [CO2]×cultivar interaction has never been tested under open-field conditions across different sites. Here, we report on trials conducted at free-air CO2 enrichment (FACE) facilities at two sites in Japan, Shizukuishi (2007 and 2008) and Tsukuba (2010). The average growing-season air temperature was more than 5°C warmer at Tsukuba than at Shizukuishi. For four cultivars tested at both sites, the [CO2]×cultivar interaction was significant for brown rice yield, but there was no significant interaction with site-year. Higher-yielding cultivars with a large sink size showed a greater [CO2] response. The Tsukuba FACE experiment, which included eight cultivars, revealed a wider range of yield enhancement (3-36%) than the multi-site experiment. All of the tested yield components contributed to this enhancement, but there was a highly significant [CO2]×cultivar interaction for percentage of ripened spikelets. These results suggest that a large sink is a prerequisite for higher productivity under elevated [CO2], but that improving carbon allocation by increasing grain setting may also be a practical way of increasing the yield response to elevated [CO2].
有证据表明，水稻品种对二氧化碳浓度升高（[CO₂]）的反应有所不同，但[CO₂]与品种的相互作用从未在不同地点的田间条件下进行过测试。在此，我们报告在日本两个地点，静石（2007年和2008年）和筑波（2010年）的自由空气二氧化碳富集（FACE）设施中进行的试验。筑波生长季的平均气温比静石高5℃以上。在两个地点测试的四个品种中，糙米产量的[CO₂]与品种的相互作用显著，但与地点年份没有显著相互作用。具有较大库容量的高产品种对[CO₂]的反应更大。包括八个品种的筑波FACE试验显示，产量提高的幅度（3 - 36%）比多地点试验更大。所有测试的产量构成因素都促成了这种提高，但对于成熟小穗的百分比，[CO₂]与品种的相互作用非常显著。这些结果表明，大库容量是[CO₂]升高条件下提高生产力的先决条件，但通过增加结实率来改善碳分配也可能是提高对[CO₂]升高的产量反应的一种切实可行的方法。
