烤烟氮、钾营养及其平衡的变化规律研究

Study on Discipline of NK and N/K Ratio of Flue-cured Tobacco

通过小区试验的方法 ,探讨了不同生育期土壤氮、钾水平及烤烟中部烟叶氮钾含量、氮钾平衡的变化。结果表明 :(1)在烤烟整个生育期中土壤氮素与烟叶含氮量呈下降趋势 ,而烟叶含氮量在 6 4～ 78d出现一个高峰值 ,氮、钾肥施用多 ,则高峰值出现的时间早。 (2 )土壤与烟叶含钾量随着时间的推移呈下降趋势 ,但烟叶含钾量在 78d时略有升高。 (3)烟叶氮 /钾比随生育期推移呈上升的趋势 ,施氮量越多 ,最大值越高 ;而土壤氮

Field trials were carried out to study the changes of nitrogen and potassium levels in soils and contents and balance of nitrogen and potassium in leaves in middle position of flue cured tobacco in central Yunnan Province. Results showed as follows: (1) Contents of nitrogen in soils and leaves decreased gradually in the whole period of growth. Contents of nitrogen in leaves had a peak between 64-78 days, and the more the fertilizing rates of N, K fertilizer the earlier this peak got to. (2) Contents of potassium in soils and leaves decreased gradually in whole period of growth, but the contents of potassium in leaves had a higher point in the 78?th day. (3) The ratio of nitrogen to potassium (N/K) in leaves had the tendency of increasing in the whole period of growth. The peak came in the 108?th day. But there were not any changing regulation of the N/K ratio in soils.