不同氮肥施用量对胡椒生长及花穗的影响

以热引1号胡椒为材料,研究不同施氮量(0、3.5、7、10.5、14 g/株)处理对幼龄胡椒叶片SPAD值、叶片氮含量、土壤硝态氮含量、胡椒长势和花穗发育的影响及叶片氮含量与花穗发育的相关关系。结果表明:施氮量由0增加到7 g/株,胡椒叶片SPAD值、叶片氮含量均逐渐增加,促进胡椒生长。施氮量为10.5~14 g/株时,胡椒叶片的SPAD值降低,叶片氮含量减少,胡椒株高和冠幅均受到抑制,开花时间晚,花量较少,且土壤中残留的硝态氮增加。因此,在本试验条件下,幼龄胡椒适宜的施氮量为3.5~7 g/株。在生产中,除了应控制氮肥的施用量外,还应增加磷钾肥的施用。 

Different Nitrogen Rate on Growth and Flowering of Pepper

The experiment was conducted with five nitrogen（N）treatments in pepper. The application amount for   the five N treatments was 0， 3.5， 7， 10.5 and 14 g N per plant，respectively， and abbreviated as N1，  N2， N3， N4 and N5. SPAD reading， N content of leaves， plant height and canopy width of pepper，  soil  nitrate content，and flowering time were measured or recorded to assess N rate  on pepper. The  results showed  that SPAD reading and N content of the  leaves increased as more  N used. Meanwhile  rational N rate  promoted   pepper growth. However， excessive N reduced SPAD reading and N content  of  the  leaves.Plant  growth  of  pepper was inhibited by excessive N application. Flowering was delayed and the number  of  flower  spike  were  reduced  with  excessive  N.  And  excessive  N  increased  soil  nitrate  content.  Therefore， the appropriate N recommendation is 3.5 to 7 g per plant in the experiment. In addition to decreasing amount of N fertilizer， the application of phosphate and potassium fertilizers should be considered in production.