基于SPAD值的烤烟氮素营养诊断研究

Study on nitrogen nutrition diagnosis of flue-cured tobacco based on SPAD value

为探究SPAD值在烤烟氮素养分诊断中的作用,以云烟100为试材,设置了6个不同氮肥水平的田间试验,分析了烤烟叶片SPAD值与氮素营养诊断指标、施氮量的关系以及施氮量对产量的影响。结果得出产量与施氮量呈二次函数关系,函数关系式为Y=-0.07X^(2)+18.07X+2165.34,根据产量与施氮量的关系确定了最佳经济施肥量,为124.5 kg/hm^(2),对应的最佳经济产量为3330.4 kg/hm^(2);建立了基于叶片SPAD值的烤烟氮肥推荐施肥标准。其中最适SPAD值范围为37.11~46.06,可作为团棵期和旺长期氮素营养诊断的指标,并能推荐氮肥的施用。

In order to explore the role of SPAD value in the diagnosis of nitrogen nutrients in flue-cured tobacco,using Yunyan 100 as the test material,6 field trials were set up with different nitrogen fertilizer levels,the relationship between SPAD value of flue-cured tobacco leaves,nitrogen nutrition diagnostic indicators,and nitrogen application rate were analyzed and the effect of nitrogen application rate on yield was investigated.The results showed that the yield and nitrogen application rate were related by quadratic function,which was Y=-0.07X^(2)+18.07X+2165.34.According to the relationship between yield and nitrogen application rate,the optimal economic fertilization rate was determined to be 124.5 kg/hm^(2),and the corresponding optimal economic yield was 3330.4 kg/hm^(2).The recommended fertilization standard for flue-cured tobacco based on the leaf SPAD value was established.Among them,the most suitable SPAD range was 37.11~46.06,which can be used as an index for the diagnosis of nitrogen nutrition in the resettling group tree stage and prosperous stage,and the application of nitrogen fertilizer can be recommended.