Studies on Leaf Analysis. : V. Nutritional balance of N, P and K elements in the leaves of wheat plants

[摘要] When the percentage of N, P or K for the total concentration of N+P+K in L. B., L. S. and I. N. of wheat plants in the Part IV is named N, P & K composition percentage, (for example, N composition percentage is N/(N+P+K)mgm-atom No./100g Dry matter), this composition percentage in the top leaf blade on a given plot is almost constant during the whole vegetative growth periods, and varies characteristically with different fetilizer treatments. The figures are shown in Fig. 1. The composition percentage of NPK plot was almost equal to that of Nil plot, and it maintained normal balance of nutrition, but in the PK plot, N was less, P and K more in the NK plot, P was less, N and K more in the composition percentage as compared with the NPK plot. Thus the NPK composition percentage of top leaf blade reflected well the NPK fertilizer treatments (Fig. 2). Analysis of variance of the NPK composition percentage to the NPK fertilizer elements is shown in Table 2. By examining the NPK composition percentage of top leaf blade, the normal and abnormal status of nutrition as well as the fertilizer elements supplied can be diagnosed.

[学科分类] 农业科学（综合）