Development of theory on assimilation, transport and distribution processes of rice silica content to cope with global change

对过去的FACE(自由空气CO2富集法)实验中采集的水稻样品的二氧化硅含量进行了重新分析，结果表明，高二氧化碳降低了水稻叶鞘、茎和叶片中的二氧化硅含量。推测植物各部位的二氧化硅分布与高CO2增加干物质重量所预期的二氧化硅含量并不一致，从而导致二氧化硅含量的降低。高CO2还降低了穗表面的二氧化硅含量，这可能使植物对生物胁迫敏感。由于高CO2降低了穗部蒸腾作用而不考虑二氧化硅含量的降低，高CO2使穗部温度升高，从而增加了高温胁迫的风险。

Re-analyzing of silica content of rice sampled in the past FACE (Free-Air CO2 Enrichment) experiment showed that silica content decreased by high CO2 in sheath, culm and leaf blade. It was inferred that silica distribution to each part of plants did not correspond to the silica amount expected from the increase of dry matter weight by high CO2, resulting in the decrease of silica content. Silica content in panicle surface also decreased by high CO2, which might make plants susceptible against the biotic stress. As the panicle transpiration decreased by high CO2 regardless of silica content decrease, panicle temperature increase by high CO2, which should raise the risk of heat stress