STUDY ON THE NITROGEN, PHOSPHORUS,POTASSIUM NUTRITION AND THEIR DIAGNOSIS IN CHINESE FIR SEEDLINGS
Zhong Anliang Yu Xintuo ( Department of Forest Science )
An optimized design was adopted to arrange the pot fertilizer experiment including three factors N.P.K with five levels i. e N:0.0, 0.5, 1.0, 1.5, 2.00; P:0.0, 0.3, 0.6, 0.9, 1.2; K:0.0, 0.4, 0.8, 1.2, 1.6(g/pot). The soil for the trial was lack of availadle N. P. The results of the research showed that the treatments N3P3K1, N2P4K4and N1P3K3With proper combination between N and P, had higher or highest availability of N. P. K. The availability of N under the condition of high N and low P was low, which resulted in the waste of N and in the depression of the growth and some physiological activities of Chinese fir seedlings. Ppro-moted the adsorption of N remarkably. There were significant correlations of one variable binomial equation between most of the items of growth and physiology and the total N, total p, total K in the leave of Chinese fir seedlings. The models were used for the nutritional diagnosis to obstain more pratical results. DRIS ( Diagnosis Recomme ndation and Integrated System ) was adopted to diagnose the status of the balance of the various elements and to determine the sequences of fertilizing and the proper ratios of the elements in various periods of growth precisely. Therefore, the more integrated diagnosis indices of Chinese fir seedlings were obtained by combining the two methods.