墨兰矿质营养研究

STUDY ON MINERAL NUTRITION OF CYMBIDIUM SINENSE

本文介绍墨兰在氮、磷、钾不同水平条件下的生长发育状况、叶片褐斑病发病率和一些生理生化的变化．试验确定墨兰生长发育最佳的氮、磷、钾浓度，提出判断墨兰体内磷和钾营养状况的生化指标，对合理栽培墨兰有指导意义．

This paper summerized effects of N, P, K at various concentrations on the growth and development of Cymbidium sinense (Andr.)Willd. grown in soilless medium.Plant growth was the best when supplied with ammonium and nitrate together as nitrogen source. This agrees with the general practice of using ammonium nitrate as nitrogen fertilizer for growing Cymbidium. The suitable concentrations (mmol/L) of N P, K for best growth were 1～ 10, 0.2～1.0 and 5 ～ 10 respectively. In normal culture conditions, the content of K was more than that of N and P. The ratio of N, P, K was 6:1:9. Therefore, attention should be paid to K fertilizer in cultivated C. sinense. At optimal K supplied, the plant grew rapidly in leaf, with a considerable number in flower and low rate of leaf brown spot disease. Three methods of preliminary biochemical diagnosis for K nutrition in this plant, including K content of leaf, % of reducing sugar/soluble sugar of leaf and pyruvate kinase activity in leaf, are also suggested.