包膜氮肥配施不同用量钾肥对多年生黑麦草植株生理指标及产量的影响

通过盆栽试验研究包膜氮肥配施不同用量钾肥对多年生黑麦草(Lolium perenne)生长特性及产量的影响,以期明确适宜黑麦草生长的最佳施肥配比。结果表明,与普通尿素相比,包膜氮肥显著提高了黑麦草植株SPAD值、株高、叶面积、净光合速率(P<0.05),明显延长了黑麦草绿期,防止早衰。施用等量钾肥条件下,包膜氮肥处理比普通尿素处理4次刈割的SPAD值分别提高11.2%、6.9%、33.6%和195.2%,株高分别增加14.1%、6.0%、25.1%和85.4%。包膜氮肥处理较普通尿素处理的干草产量提高了12.4%~25.0%。包膜氮肥配施中量钾肥处理能最大程度增加叶面积指数和净光合速率,提高黑麦草产量,因此推荐作为最佳施肥配比,为黑麦草的氮钾肥合理施用提供理论依据。

Effects of polymer-coated nitrogen fertilizer combined with different potassium fertilizer dosages on physiological indicators and yield of ryegrass

To determine the best fertilization ratio for the growth of ryegrass(Lolium perenne),a potted experiment was performed to study the effect of polymer-coated nitrogen fertilizer combined with different potassium fertilizer dosages on the growth characteristics and yield of ryegrass.Compared with common urea,the polymer-coated nitrogen fertilizer significantly increased the SPAD(soil plant analysis development)value,plant height,leaf area,net photosynthetic rate,prolonged the green stage,and prevented the premature senescence of ryegrass(P<0.05).Using the same amount of potassium fertilizer,the SPAD values of four grass cuttings increased by 11.2%,6.9%,33.6%,and 195.2%,respectively,and the plant height increased by 14.1%,6%,25.1%and 85.4%,respectively.Compared with urea treatment,polymer-coated nitrogen fertilizer increased the dry mass weight of ryegrass by 12.4%~25.0%.The leaf area index and net photosynthetic rate of ryegrass increased maximally following polymer-coated nitrogen fertilizer with moderate amounts of potassium fertilizer.Thus,it is recommended as an optimal fertilization ratio,providing a theoretical basis for the rational application of nitrogen and potassium fertilizer in ryegrass production.