控释尿素对大棚黄瓜氮素利用和品质的影响

The effect of coated urea on quality change tendency of soil nutrient and nutrient utilization of cucumber in greenhouse

采用混料试验中的单形重心设计方案,将包膜控释尿素在大棚黄瓜上进行田间试验,对不同时期黄瓜品质、土壤氮素的变化趋势和黄瓜果实、茎叶的吸氮规律进行了图解分析,对控释尿素D30、D60和普通尿素配合下的氮素利用率进行了研究。结果表明:控释尿素无论单施或配合施用随生长时期均有提高黄瓜的安全品质和营养品质的趋势。控释尿素在黄瓜生长后期可保证碱解氮和氨态氮的持续供应,为一次性施用包膜控释尿素可以满足作物全生育期对养分的供应提供了更为有力的依据。D30D60、UD30D60配合施用随生长期延长果实吸氮量呈上升趋势;各处理茎和叶的吸氮规律较为一致;果实的总吸氮量各处理均明显比普通尿素高,尤以D30D60处理最高。果实、茎、叶三项的总吸氮量与果实吸氮量具有相同的规律。D30D60氮素利用率最高为41.0%,比普通尿素相对高130.32%,其次UD30D60为39.1%,比普通尿素相对高119.73%,在黄瓜生产中D30D60、UD30D60两种施肥配方均可选择。

The method of the simplex centroid design of mixture experiment of greenhouse cucumber was used to establish the production model and carried out and the picture analysis was made of cucumber quality, the change tendency of soil nitrogen and the absorption regulation of stem and leaves in different time. A study study was also made on the nitrogen utilization of using both coated urea D30, D60 and normal urea. The results showed that： From analytic comparison of production, the best production was made by using D30 and D60 cooperatively, but there were no obvious difference in using D30D60 together; From the model of production analysis, if the amount of pure nitrogen was used per hm^2 like： X1 （U） = 105.0 kg, X2（D60） = 262.5 kg, X3 （D30） = 157.5 kg, it would take the top quality to up to 122. 595 t/hm^2. No matter single or complex fertilizing of coated urea, the tendency quality and nutrient of cucumber would be improved a lot with time passing. The coated urea would supply continually cucumber in the later time of growing with Alkal. N and Atom. N, which would show the evidence of using coated urea one time would meet the nutrient needs of the crop growth. The time of using D30D60 and D30D60 cooperatively is longer and the absorption of nitrogen in fruit is higher, but the absorption of nitrogen in stem and leaf are similar. The total nitrogen absorption of coated urea was higher than normal urea in greenhouse cucumber, especially the top was D30D60. The total nitrogen absorption of fruit, stem and leaf had the same regulation as fruit did. The top nitrogen utilization of D30D60 was 41.0 %, about 130.32% more than normal urea, then the nitrogen utilization of D30D60 was 39.1%, about 119.73% more than normal one, so, two methods of using D30D60 and UD30D60 cooperatively could be choosen.