不同氮磷用量对红枣果实品质和产量的影响

水资源匮乏与土壤肥力不足一直是阻碍新疆红枣果业发展的重大问题。为探究不同氮磷用量对红枣产量和品质的影响，给红枣树合理施肥提供指导。在南疆阿里尔市枣园，以主干结果型灰枣树为研究对象，采用单因素随机区组试验设计，在滴灌条件下研究了不同施氮量和施磷量下灰枣果实可溶性糖、可滴定酸、糖酸比、Vc等品质指标与产量的变化。结果表明，各施氮处理吊干枣的可溶性糖含量、可滴定酸含量均明显高于鲜枣，但鲜枣的Vc含量和糖酸比却均明显高于吊干枣。随施氮量增加，吊干枣果实中可滴定酸含量、糖酸比均呈先降低后增加趋势。其中以施N 690.0 kg/hm2时吊干枣可溶性糖含量较高，糖酸比较低；施N 495.0 kg/hm2时吊干枣可滴定酸含量较低，糖酸比较低；施N 592.5 kg/hm2时鲜枣Vc含量较高，糖酸比较高，吊干枣产量最高，为8 061 kg/hm2。各施磷处理鲜枣的可溶性糖含量、可滴定酸含量明显低于吊干枣，但鲜枣的Vc含量明显高于吊干枣，糖酸比波动较大，变化无明显规律。随施磷量增加，鲜枣和吊干枣果实中可溶性糖含量和Vc含量均呈先增加后降低趋势；可滴定酸含量呈先降低后增加趋势；糖酸比鲜枣呈先增加后降低再增加趋势，吊干枣呈先降低后增加趋势。施P2O5 517.5 kg/hm2时吊干枣可溶性糖含量和鲜枣Vc含量较高，吊干枣产量最高，为6 983 kg/hm2。施P2O5 435.0 kg/hm2时吊干枣可滴定酸含量较低。综合可见，施N 495.0 kg/hm2、P2O5 517.5 kg/hm2 为南疆枣园最优施肥量。

Effects of Different Application Rates of Nitrogen and Phosphorus on Fruit Quality and Yields of Red Jujube

The shortage of water resources and soil fertility has always been a major problem restricting the development of jujube industry in Xinjiang. To explore the effects of different application rates of nitrogen and phosphorus on the yield and quality of jujube and to provide references for rational fertilization of jujube trees, trunk-fruit type grey jujube tree was taken as the material and single factor randomized block experiment design was adopted to study the effects of different application rates of nitrogen and phosphorus on grey jujube quality indexes, such as contents of soluble sugar, titratable acid, sugar-acid ratio and Vc, and grey jujube yields under drip irrigation conditions in Arier Municipality of southern Xinjiang. The results showed that contents of soluble sugar and titratable acid in hanging dried jujube under all nitrogen treatments were significantly higher than that of the fresh jujube, but Vc content in fresh jujube was significantly higher than that in hanging dried jujube. With the increase of nitrogen application rate, titratable acid content and sugar-acid ratio in hanging dried jujube were decreased first then increased, among which the soluble sugar content of hanging dried jujube was relatively higher and the sugar-acid ratio was relatively lower at N application rate of 690.0 kg/ha, titratable acid content and sugar-acid of hanging dried jujube were relatively lower at N application rate of 495.0 kg/ha, and Vc content of fresh jujube and the sugar-acid ratio were higher at N application rate of 592.5 kg/ha under which the yield of hanging dried jujube peaked as well with an average data of 8 061 kg/ha. Contents of soluble sugar and titratable acid in fresh jujube under all phosphorus treatments were significantly lower than that of the hanging dried jujube, but Vc content in fresh jujube was significantly higher than that in hanging dried jujube, and the sugar-acid ratio varied with no obvious pattern of change. With the increase of phosphorus application rate, the soluble sugar content and Vc content in fresh and hanging dried jujube fruits showed a trend of increasing first then then decreasing, the content of titratable acid was decreased first and then increased, the sugar-acid ratio showed a trend of increasing first then decreasing, and then increasing again in fresh jujube, whereas sugar-acid ratio in hanging dried jujube showed a trend of decreasing first then increaseing. The Vc contents of hanging dried and jujube were relatively higher and the yield of hanging dried jujube, i.e., 6 983 kg/ha, peaked at P2O5 application rate of 517.5 kg/ha, the titratable acid content in hanging dried jujube was low at P2O5 application rate of 435.0 kg/ha. Therefore, N application rate of 495.0 kg/ha, and P2O5 application rate of 517.5 kg/ha were considered as the optimum application rate of fertilizers for jujube production in southern Xinjiang.