黄土丘陵区旱作山地红枣氮磷钾施肥效应研究

采用N、P、K三因素D饱和最优设计,在黄土高原丘陵区秸秆覆盖条件下进行了矮化密植枣树N、P、K肥效及优化施肥模式田间试验。结果表明:氮磷钾施肥对红枣产量的综合效应表现为K肥N肥P肥。试验建立了黄土高原丘陵区秸秆覆盖条件下矮化密植枣树优化施肥模式,根据优化施肥模式,提出了在18 000~25 000kg·hm-2范围内红枣高目标产量的N、P、K优化施肥方案:施N用量为267.8~518.6 kg·hm-2,施P2O5用量为83.7~360.04 kg·hm-2,施K2O用量为438.0~491.0 kg·hm-2。氮磷钾施肥处理比不施肥处理提高红枣可滴定酸、总糖、还原糖、可溶性固形物的含量,依次为32.5%、0.82%、1.8%、1.01%,而氮磷钾施肥处理与不施肥处理相比红枣黄酮含量相对降低,其降低百分比为40.4%,表明红枣施氮磷钾肥比不施肥品质好。

Model of fertilization on jujube under dry farming condition in mountainous region of Loess Hilly in North Shaanxi

Upon the employment of a three-factor and D-optimum repercussion layout for the use of N ,P and K fer-tilizers ,a field experiment was carried out to explore the optimal rates of fertilizer application and the responding models for mountain jujube under the condition of straw mulching to the fertilizers in the loess plateau in north Shaanxi province . The results showed that the combined effects of NPK fertilizers on jujube yield followed the order of K > N > P fertilizers . Through the field experiment ,the responding models of mountain jujube under the condition of straw mulching to N ,P and K fertilizers were found out and the effects of N ,P and K fertilizers on mountain jujube under the condition of straw mulching were explored .Based on the responding models of yields to N ,P and K fertilizers ,an optimized fertilization plan on N ,P and K fertilizers was put forward for a high target yield of 18 000 ~ 25 000 kg·hm - 2 ,specific as the fol-lows :N fertilizer rate of 267 .8 ~ 518 .6 kg·hm - 2 ,P2O5 fertilizer rate of 83 .7 ~ 360 .0 kg·hm - 2 ,and K2O fertilizer rate of 438 .0 ~ 491 .0 kg·hm - 2 .NPK fertilizer treatments had increased the contents of titratable acid ,total sugar ,reducing sugar ,and soluble solids by 32 .5% ,0 .82% ,1 .8% ,and 1 .01% ,relatively from no fertilization treatments .But NPK fertilizer treatments relatively decreased date flavonoid content by 40 .4% from no fertilizer treatments .In conclusion , NPK fertilizers resulted in better quality jujube than no fertilizers .