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

对FACE（Free-AirCO_2 Enrichment）试验中水稻样品的硅含量进行了重新分析，结果表明，高CO_2浓度使水稻叶鞘、秆和叶片中硅含量降低。据推测，硅分配到植物的各个部分不对应于硅量预期从干物质重量增加高CO2，导致硅含量的下降。高浓度CO2还降低了穗表硅含量，这可能使植物对生物胁迫敏感。由于高CO2处理降低了穗部蒸腾速率，而不考虑硅含量的降低，因此高CO2处理提高了穗部温度，增加了热胁迫的风险

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