摘要
本文研究了枣树叶片中N、P、K、Ca、Mg、Mn、Cu、Fe、Zn9种营养元素含量的季节变化动态规律。结果表明:全N的含量在初花期以前随着叶龄的增大而迅速降低。在初花期至幼果发育前期较稳定且较低,在幼果发育中期迅速增高,采收后逐渐下降;全P和全K的含量随着叶龄的增加而减小,至叶片成熟后则较稳定;Ca和Mn的含量随着叶龄的增加而迅速增高;Fe的含量在初花期出现低谷,从盛花期到果实发育中期处于稳定的高水平状态,果实进入白熟后逐渐下降,采果后则变动不显著;Mn、Cu和Zn3元素含量的变化趋势与N素水平密切相关;施尿素显著地提高了大多数物候期中叶片全N和Mn的含量,也显著地降低了大多数物侯期中叶片全P、全K和Zn的含量:在年生长周期内,各营养元素的叶分析诊断大多数有2个适宜的采叶时期。
This paper is mainly concerned with the seasonal dynamics of nine essential elements in the leaves of jujube (Zizyphus jujuba). It also discusses the effects of urea application on the concentrations of these nutritional elements in jujube leaves.The results of this study are summarized as follows, the concentration of total N falls rapidly with the growth of the leaves before anthesis, keeps low and invariable during the period from the bloom to the beginning of the fruit-bearing, increases sharply during the middle period of the fruit-bearing, and gradually declines after harvest; the concentrations of P and K drop with the growth of the leaves and show little change when they reach the stage of maturity; there are fast accumulations of Ca and Mn ;the concentration of Fe is very low at the beginning of the bloom,high and stable during the period from the full bloom to the middle of the fruit-bearing, low when the skins of the fruits turn white,and stable after harvest;the dynamics of foliar Mg,Cu and Zn have something to do with the levels of N;urea application significantly enhances the concentrations of N and Mn in most phenophases, but significantly reduces the concentrations of P,K and Zn in the leaves of most phenophases. In the annual growing season of jujube trees,each foliar element studied has at least one stable period suitable for the diagnosis samplings, and a large part of them have two periods for this purpose.
出处
《经济林研究》
1989年第2期23-29,共7页
Non-wood Forest Research
关键词
枣
营养元素
尿素
叶片
Zizyphus jujuba, Nutritional element, Leaf analysis, Urea
