不同追肥浓度对生菜生长、氮素利用及土壤环境的影响.docVIP

不同追肥浓度对生菜生长、氮素利用及土壤环境的影响 　　摘要：以生菜为研究对象，在基肥氮素用量相同的条件下，研究了两种复合肥的追肥浓度对生菜生长、氮素利用及土壤环境的影响。结果表明，（1）在发芽期和幼苗期，施用基肥可以明显促进生菜植株生长；发棵期，在低追肥浓度5%时，复合肥料1、2获得的最大干物质积累量分别为4.02 g和3.18 g；产品器官形成期，在中追肥浓度10%时，复合肥料1、2获得的最大干物质积累量分别为16.24 g和13.72 g。复合肥料1、2在低追肥浓度5%时产量最高，分别比次高产增产22.05%和30.85%。（2）植株全氮含量和肥料氮素利用率随着追肥浓度的增加呈现先升高后降低的趋势。复合肥料1，植株全氮含量和肥料氮素利用率均在低追肥浓度5%时取得最大值，分别为3.97 g/kg和38.08%；复合肥料2，肥料氮素利用率在低追肥浓度5%时取得最大值48.17%，植株全氮含量则在中追肥浓度10%时取得最大值4.02 g/kg，但两追肥浓度下植株的全氮含量差异不大。（3）不同追肥处理，复合肥料1在中追肥浓度10%时土壤的全氮含量最低，为0.95 g/kg；复合肥料2在低追肥浓度5%时土壤的全氮含量最低，为0.87 g/kg，但两追肥浓度下土壤的全氮含量均比对照组高；不同追肥浓度对10～20 cm中层次的土壤致酸作用较明显，此外施肥也在一定程度上增加了土壤有机质含量。综合以上指标的测定，为实现生菜的优质高产，建议追肥浓度以5%～10%为宜，产品器官形成期可以适当增加追肥浓度。 　　关键词：追肥浓度；生菜；生长；氮素利用；土壤环境 　　中图分类号：S636.2；S143 文献标识码：A 文章编号：0439-8114（2016）12-3026-05 　　DOI：10.14088/j.cnki.issn0439-8114.2016.12.010 　　Abstract： Experiment with lettuce as the research object， the nitrogen fertilizer under the same conditions，the two kinds of compound fertilizer concentration of growth and nitrogen utilization and soil environment effect were studied. The results showed that：（1）Before topdressing in lettuce germination stage and seedling stage， basal manure could significantly promote the growth of plant compared with control group； For compound fertilizer 1 and compound fertilizer 2，tillering stage in the fertilizer concentration was 5% the maximum dry matter accumulation， respectively 4.02 g and 3.18 g，the product of organ formation stage in the top dressing at the concentration of 10% the maximum dry matter accumulation，respectively 16.24 g and 13.72 g，and in the top two at the concentration of 5% fertilizer yield was the highest， respectively increased by 22.05% and 30.85% times of high yield.（2）The total nitrogen content and nitrogen fertilizer use efficiency increased with fertilizer concentration increased firstly and then decreased. For compound fertilizer1， total nitrogen content and nitrogen fertilizer utilization rate in low fertilizer concentration of 5% reached the maximum value， 3.97