不同施氮水平对旱地兰州百合养分累积与氮肥利用的影响

Effect of different N rates on nutrient accumulation and nitrogen use efficiency in rainfed land Lanzhou lily

在兰州市七里河区西果园大田条件下,研究了在施用磷肥150 kg/hm2和钾肥225 kg/hm2基础上,不同施氮水平（0,75,150和225 kg/hm2）对旱地兰州百合干生物量、养分累积动态及氮肥利用的影响,旨在揭示兰州百合需肥规律,为其规范化栽培提供依据。结果表明,适宜施氮量可促进兰州百合植株生长,提高鳞茎养分的转化吸收效率。鳞茎氮磷钾养分吸收不同步,累积量依次为K〉N〉P。施氮量只影响鳞茎干生物量和养分的阶段累积量,不改变其累积动态趋势。随施氮量的增加,鳞茎产量、氮累积量和氮肥利用率均有不同程度地提高,施氮量为150kg/hm2时三者均最高,分别达（8 982.1±845.8）kg/hm2,（29.123±1.767）kg/hm2和（4.97±2.16）%。当施氮量达225 kg/hm2时各指标均下降。施氮量为75 kg/hm2时氮肥效率最大,为（107.36±11.21）%,此后随氮肥量的增加氮肥效率极显著下降。综合考虑各因素,建议兰州百合基肥的施氮量应为75～150 kg/hm2。

Using 150 and 225 kg/hm2 of P and K fertilizers as basal fertilizer in the West Orchard village of Lanzhou,field experiments were conducted to study the effects of different nitrogen fertilizer levels（0,75,150 and 225 kg/hm2） on the cumulated dynamics of bulb biomass and nutrition,fertilizer use efficiency（NFE） in rainfed land Lanzhou lily（Lilium davidii） in order to explore its requirement pattern for the fertilizer and provide basis for its standardization cultivation.The results showed that rational N fertilization could improve the plant＇s construction,nutrition transformation and accumulation efficiency,but the steps of N,P and K absorption differed,resulting in accumulation order in KNP.The nitrogen levels only affected the stage-accumulated amounts of bulb biomass and nutrients rather than their accumulative dynamic trends.The bulb yield,N accumulation and N-fertilizer use rate（NFUR） were all increased with the amounts applied N fertilizer and get at the highest values when applied 150 kg/hm2 of N fertilizer,which were（8 982.1±845.8） kg/hm2,（29.123±1.767） kg/hm2 and（4.97±2.16）%,respectively.On the application of N fertilizers reached to 225 kg/hm2,all the indicators decreased.When applied 75 kg/hm2 of N fertilizer,the NFE was the highest and then the value great significantly decreased with amounts of N fertilizer.Considering integrated factors,the basal N-fertilizers should between 75-150 kg/hm2.