Correlations between Nitrogen Content and Multispectral Image of Greenhouse Cucumber Grown in Different Nitrogen Level

Short fruit cucumber was chosen as object. Different nutrition conditions were applied to cultivate plants.CCD camera with special filters was used to gather images. Correlation analysis results shows that four indexes, CNDVI, GNDVI, NDGI and NDVI, had much higher correlation with nitrogen content of cucumber leaves. LS-SVM algorithm was proposed to construct models between vegetation indexes and nitrogen content. The results verified that the method of CCD camera with filters to get multispectral images could be used for analyzing nitrogen content of cucumber leaves.