窒素施肥曲線を用いた花卉類の栄養管理法の開発

A serious ploblem has recently come to light, that excessive fertilization in horticultural production is often associated with salt accumulation in soil and pollution of the hydrosphere around the culture field. Optimum fertilization with value and timing should be a balance between crop nutient absorption values, and fertilization. In previous studies for cut flower production, I found that the rate of plant growth closely paralleled the amount of nitrogen absorption. When nitrogen supply was unrestricted, increased nitrogen uptake frequently led to excessive plant growth and decreased cut flower quality. To produce economically marketable cut flowers, down-regulated nitrogen application curves(NAC) of standard type chrysanthemum (Dendranthema grandiflorum), spray chrysantthemum (Dendranthema grandiflorum), prairie gentian (Eustoma grandiflorum) and marguerite (Chrysanthemum frutescens) were developed. These fertilization methods are economical adn do not raise environmental contamination from fertilizer residue.