供氮水平对烤烟硝酸盐、亚硝酸盐和钾素含量的影响

目的]为生产优质低害的烟叶提供科学依据。方法]通过大田试验,研究不同供氮水平(0、22.5、45.0、67.5和90.0 kg/hm2)对烤烟硝酸盐、亚硝酸盐及钾素含量的影响。结果]随着施氮量的增加,上部烟叶的硝酸盐含量和中部烟叶的亚硝酸盐含量呈上升趋势,施氮量达到45.0 kg/hm2后下降;中部烟叶的硝酸盐含量和上、下部烟叶的亚硝酸盐含量呈下降趋势,但在施氮量90.0 kg/hm2时其含量会大幅度升高;施氮量为45.0 kg/hm2的下部烟叶硝酸盐含量最高,上、中、下部烟叶钾含量也最高。烟叶硝酸盐、亚硝酸盐和钾含量因部位不同而各异,但其差异均未达到显著水平。结论]氮用量为67.5 kg/hm2时有利于降低中、下部烟叶硝酸盐含量和各部位烟叶亚硝酸盐含量。

Effect of Different Nitrogen Application on Nitrate, Nitrite and Potassium Content in Flue-cured Tobacco Leaf

Objective] The study aimed to provide the scientific basis for production of tobacco leaf with high quality and low harm.Method] In the field test,the effect of different N levels(0,22.5,45.0,67.5,90.0 kg/hm2) on content of nitrate,nitrite and potassium in flue-cured tobacco leaf was studied.Result] With the increment of N rate,the nitrate content in upper leaves and nitrite content in middle leaves showed rising trend.When the application of N reached 45.0 kg/hm2,the nitrate content in middle leaves and the nitrite content in upper and lower leaves showed downward trend,but their content could be greatly increased when the application of N reached 90.0 kg/hm2.When the application of N was 45.0 kg/hm2,the nitrate content in lower leaves was the highest,K content in upper,middle and lower leaves were also the highest.In different parts of tobacco leaves,the content of nitrate,nitrite and potassium were different,but their difference were not significant Conclusion] It was beneficial to decrease nitrate content in middle and lower leaves and nitrite content in each part of tobacco leaves when the application of N was 67.5 kg/hm2.