臭氧和氮肥交互对小麦干物质生产、N、P、K含量及累积量的影响

利用中日合作建立的亚洲首个稻麦轮作开放式臭氧浓度升高（ozone-free air controlled enrichment,O3-FACE）平台,选取小麦品种（Tritcium aestivum）扬麦16为试材,研究了不同臭氧和氮肥水平下,小麦不同部位干物质量以及N、P、K质量分数的变化。结果表明,臭氧胁迫下,常氮水平小麦根、叶和穗干物质量以及根冠比与对照相比均显著降低,降幅分别为37.4%、17.4%、12.8%、29.8%,而增施氮肥后,小麦根叶穗及根冠比与常氮下相比均显著增加,增幅分别为60.5%、23.2%、10.7%、43.6%;常氮条件下,臭氧浓度升高明显降低N、P、K累积量及成熟期叶中N、P、K质量分数,降幅分别为10.93%、11.65%、7.64%、23.87%、14.81%、14.9%,而成熟期穗中N、P、K质量分数明显增加,增幅分别为6.15%、10.34%、13.12%,增施氮肥后,N、P、K累积量及小麦叶中N质量分数与常氮相比明显增加,增幅分别为15.58%、11.91%、9.00%、10.74%,叶中P、K质量分数也有所增加但增幅很小,而增施氮肥对其他部位的N、P、K质量分数影响不大。臭氧和氮肥对茎部干质量及N、P、K质量分数影响均不明显。总之,增施氮肥对小麦在臭氧胁迫下的生物量累积和养分累积有一定的缓解作用。

Interactive effects of elevated ozone and nitrogen on dry matter production,concentration and accumulation of nitrogen, phosphorus and potassium in winter wheat

An O3-Free Air Control Enrichment （O3-FACE） experiment was conducted in 2008-2009 to study the interactive effects of elevated ozone and nitrogen on the dry matter production, the concentrations and accumulation of nitrogen, phosphorus and potassium in winter wheat CYang Mai 16）. The winter wheat was exposed to two levels of ozone （Ambient and 1.5Ambient） and two levels of nitrogen supply （210 kg-hm-2 and 250 kg·hm2） under open-field conditions. The results showed that elevated ozone significantly reduced the ratio of root：shoot and the biomass of roots, leaves and spikes by 29.8%, 37.4%, 17.4%, 12.8%, respectively at the nitrocon level of 210 kg·hm2 during the period of maturing. Nitrogen supply enhanced the dry weight of roots, leaves, spikes and root：shoot ratio with the increment of 60.5%, 23.2%, 10.7%, 43.6%, respectively. The accumulation of NPK and the concentrations of NPK in leaves were decreased by 10.93%, 11.65%, 7.64%, 23.87%, 14.81%, 14.9%, respectively, at the nitrogen level of 210 kg·hm-2 during the period of maturing. But at the same treatment and period, the concentrations of NPK in spikes were increased by 6.15%, 10.34%, 13.12%, respectively. After nitrogen addition, the accumulation of NPK and concentrations of N in leaves under elevated ozone were increased by 15.58%, 11.91%, 9.00%, 10.74%, respectively, compared to ambient condition. Neither ozone nor nitrogen had any effects on the concentrations of NPK in stems. Results of this experiment suggested that 19% additional nitrogen had positive effects on biomass and N content in leaves under O3-FACE in the stage of maturing.