控释尿素与尿素配施对杭白菊产量和氮肥利用率的影响

Effects of Mixture of Controlled-release Urea and Conventional Urea on the Yield and Nitrogen Use Efficiency of Chrysanthemum morifolium

在大田栽培适量施肥和减量施肥条件下研究施用尿素、尿素与控释尿素配施对杭白菊(Chrysanthemum morifolium)产量和氮素利用率的影响。设6个处理:对照不施氮肥(CK11);适量施肥氮肥为尿素(N11)、适量施肥氮肥为尿素与控释尿素配施(N12);减量施肥氮磷钾施用量均减少1/4,对照不施氮肥(CK22),减量施肥为尿素(N21),减量施肥尿素与控释尿素配施减量施肥(N22)。结果表明,与对照相比,施氮处理提高了株花序数、花序直径和单花序质重。采收期,施肥量相同时,控释尿素与尿素配施茎叶部氮素分配比例低于单施尿素处理,花部高于单施尿素处理,表明控释尿素与尿素配施有利于氮素向花序分配,提高产量。适量施肥杭白菊产量高于减量施肥。适量施肥控释尿素与尿素配施比单施尿素增产87.96 kg.hm-2,比减量施肥控释尿素与尿素配施增产124.99 kg.hm-2。施用方式相同时,适量施肥氮肥利用率高于减量施肥,氮肥农学利用率低于减量施肥。施肥量相同时,控释尿素与尿素配施氮肥利用率、氮肥农学利用率高于单施尿素。在本试验条件下,施氮量120 kg.hm-2,控释尿素(150 d)与尿素按1︰1混合,基施用量占总施氮量50%,控释尿素(90 d)与尿素按1︰1混合,8月15日追施孕蕾肥,施用量占总氮量50%,效果最佳。

Field experiment was conducted to study the effects of applying conventional urea, conventional urea combined with controlled-release urea on Chrysanthemum morifolium yield and nitrogen use efficiency. Six treatments with three replications were set up, i.e., control （CKll）, no nitrogen fertilizer applied： Suitable fertilization rate including single conventional urea （Nil）, controlled-release urea combined with conventional urea （N12）, control （CK22）, no nitrogen fertilizer applied, phosphorous and potassium saved 1/4： Fertilization rate saved 1/4 including conventional urea （N21）, controlled-urea combined with conventional urea （N22） . Results showed that applying nitrogen fertilization increased inflorescence diameter, inflorescence numbers per plant and dry weight per inflorescence significantly as compared with control. At harvesting stage, controlled-release urea combined with conventional urea decreased nitrogen distribution ratio to stem and leaf, and increased that to inflorescence comparing with single conventional urea under same fertilization rate, this indicated that controlled-release urea combined with conventional urea was more favorable to nitrogen allotting to inflorescence, and increased yield. Yield under suitable fertilization rate was higher than fertilization rate saved 1/4. Under suitable fertilizer rate, controlled-release urea combined with conventional urea increased yield by 87.96 kg ~ hm-2 compared with single conventional urea, and 124.99 kg. hm2 higher compared with the sarfie hitrogen fertilization mode under fertilization saved 1/4. Nitrogen use efficiency treated by suitable fertilization rate was higher than that of treated by fertilization saved 1/4 under the same nitrogen fertilization mode, while nitrogen agricultural use efficiency displayed reverse tendency. Both nitrogen use efficiency and nitrogen agricultural use efficiency treated by controlled-urea combined with conventional urea were significantly higher than those of treated by single conventional urea under the same fertilization rate. Considering from economic and practical view, controlled-release urea combined with conventional urea under suitable fertilizer rate was the best nitrogen fertilization mode, namely the suitable nitrogen fertilization rate was 120 kg. hm-2. 50% of the total was used as basal, which was controlled-release urea（ 150 d）combined with conventional urea at the ratio of 1 ： 1 ; 50% of the total was used as dressing at vigorous stage, which was controlled-release urea （90 d） combined with conventional urea at the ratio of 1 ： 1.