关键词: 油菜, 品种识别, 特征参数, 苗期, 方差分析

Abstract: Hyperspectral is widely used in agriculture, and   it provides certain technical support for the classification and identification of crop varieties due to fast, efficient, accurate and non-destructive characteristics. This paper collected canopy reflectance spectra data of 11 rapeseed varieties in the pre-seedling and late seedling stages, using a total of 23 characteristic parameters in 6 aspects of hyperspectral position, amplitude, area, width, reflectance and vegetation index as indicators to measure the contribution rate of the characteristic parameters and the significance of the analysis of variance. Based on this, the effect of distinguishing and identifying on different varieties of rape was analyzed. The results showed that: from the view of contribution rate, different types of hyperspectral characteristic parameters had different ability to distinguish rape varieties, the amplitude parameter had the strongest ability to distinguish rape varieties, and the width parameter had the weakest ability to distinguish rape varieties. The overall effect from strong to weak was: amplitude parameter>area parameter>reflectance parameter>vegetation index parameter>position parameter>width parameter; from the perspective of analysis of variance, the effects of distinguishing rape varieties in different periods were different. Among them, the comprehensive effect of identifying rape varieties with vegetation index parameters was the best. The identification effect in the late seedling stage was better than pre-seedling stage, the three characteristic parameters of D_r, SD_r/SD_{b and} (SD_r-SD_y)/(SD_r+SD_y) were the best in the multiple comparison analysis of variance, which could clearly distinguish 6 varieties. Canopy spectral characteristic parameters at seedling stage could classify and identify rape varieties. The research results laid the foundation for the rapid classification and identification of crops and the rational formulation of the planting area and spatial distribution of crops.

Key words: rape, variety identification, characteristic parameters, seedling stage, variance analysis