臭氧污染对不同品种小麦磷素吸收与分配的影响

利用中国稻麦轮作O3-FACE（Free air O3 concentration enrichment）试验平台，研究了小麦（Tritcium aestivum L.）品种的物质积累、磷素的吸收与分配对大气臭氧浓度增加的响应。结果显示，大气臭氧浓度增加50%对供试小麦根和地上部的生物量积累影响差异较大，显著降低了扬麦16、烟农19和嘉兴002的产量，降幅为13.2%-35.7%，但对扬麦15和扬幅麦2号的产量无显著影响。臭氧增加导致5种小麦根系和地上部植株中磷含量呈下降趋势，而籽粒中磷含量却无显著变化。臭氧污染降低了磷在小麦根和籽粒中的积累量，促使小麦植株中磷由根部向地上部转移，增加了籽粒中磷所占比重。高臭氧浓度下扬麦16、烟农19和嘉兴002的磷偏生产力降低9.0-23.8（kg/kg， P2O5）， 磷素利用率显著降低8.2%-20.2%，但扬麦15和扬幅麦2号的磷素偏生产力与利用效率变化不明显。以上结果表明，臭氧污染具有改变小麦物质分配， 影响土壤磷素在土壤-植物系统周转的潜在风险。

Effects of ozone pollution on phosphorus absorption and distribution in different varieties of wheat

With the aid of the Free Air Ozone Concentration Enrichment (O3-FACE) system, effects of elevated atmospheric ozone on the biomass of five varieties of wheat (Tritcium aestivum L.) and phosphorus (P) uptake and distribution in wheat plant were investigated in Yangtze River delta. The results showed that the 50% increasing ozone concentration differently influenced the biomass of root and shoot of all wheat. Ozone elevation significantly decreased the yield of yangmai 16, yannong 19 and jiaxing 002 by 13.2%-35.7%, but had no significantly effect on yield of yangmai 15 and yangfumai 2 Elevated ozone decreased P content of root and shoot of all wheat, however no significant difference in the grain was found. Ozone elevation decreased P accumulation in the root and grain, and promoted P turnover from root to shoot, which increased the proportion of P in the grain to all biomass. Elevated ozone decreased partial productivity of phosphorus of yangmai 16, yannong 19 and jiaxing 002 by 9.0- 23.8 kg/kg P₂O₅, and significantly decreased utilization efficiency of phosphorus of yangmai 16, yannong 19 and jiaxing 002 by 8.2%-20.2%; however, there was no significant effect on yangmai 15 and yangfumai 2. It is quite obvious that elevated ozone pollution has a potential risks to change the matter distribution of wheat and influence phosphorus turnover in soil plant system.