水稻不同生育期磷素营养对开放式空气二氧化碳浓度增高的响应

2001年和2002年利用农田开放式空气CO₂浓度增高（FACE）系统平台,研究不同施N量条件下FACE对武香粳14号不同生育时期磷含量、磷积累、磷分配和磷效率的影响.结果表明,FACE使水稻不同生育时期植株含磷率和吸磷量显著或极显著增加,增幅分别为3.9%～20.6%和28.9%～71.4%；FACE使水稻抽穗后磷在生殖器官中的比例下降9.8%～26.3%,在营养器官中的比例增加2.2%～23.9%,均达显著或极显著水平,而FACE对抽穗前磷在叶片、茎鞘中的比例无显著影响；FACE使水稻不同生育时期单位磷的干物质生产效率、籽粒生产效率和收获指数均明显下降,降幅分别为3.7%～16.6%、6.5%～15.5%和5.4%～9.0%；氮处理以及氮与FACE处理的互作对水稻不同生育时期的磷素营养影响较小.

Effects of free-air CO2 enrichment (FACE) on phosphorus nutrition of Oryza sativa at its different growth stages

Using free-air CO2 enrichment (FACE) platform and under different nitrogen supply level, this paper studied the phosphorus nutrition of Oryza sativa at its different growth stages. The CO2 concentration of FACE platform was 200 micromol.mol(-1) more than that in ambient air, and the nitrogen supply levels were 150 kg.hm(-2), 250 kg.hm(-2) and 280 kg.hm(-2). The results showed that during rice growth period, FACE significantly increased the phosphorus content of rice plant and its phosphorus uptake by 3.9%-20.6% and 28.9%-71.4%, respectively. Before heading, FACE had little effect on the phosphorous accumulation in leaf or stake, but after heading, made the proportion of phosphorus accumulation in reproductive organ decreased by 9.8%-26.3% and that in vegetative organ increased by 2.2%-23.9% at 0.01 or 0.05 significant level. Under FACE treatment, the phosphorus use efficiency for biomass production (PUEp) at different growth stages, the phosphorus use efficiency for grain output (PUEg), and the phosphorus harvest index (PHI) were decreased by 3.7%-16.6%, 6.5% -15.5%, 5.4%-9.0%, respectively. Nitrogen supply level and its interaction with FACE had less effect on the phosphorus-nutrition of rice at its different growth stages.