关键词: 小麦, 籽粒蛋白质, 品质指标, 冠层反射光谱, 叶片含氮量

Abstract: Quantitative relationships of grain protein content and relevant quality traits to canopy reflectance spectra and plant nitrogen status in wheat were investigated in the experiments under varied nitrogen conditions. The results showed that grain protein content, sedimentation value and falling number could be predicted by canopy reflectance spectra during filling. Monitoring of gliadin and glutenin contents in grains by canopy reflectance spectra at maturity showed high reliability. There were high correlations between grain protein content and leaf nitrogen content at 14 days after anthesis (mid-filling stage), and the latter could be well estimated by the ratio vegetation index RVI (1220, 710) at this stage. Therefore, the reflectance spectra at mid-filling could be used to monitor grain protein content indirectly. These results suggest two approaches to monitor grain protein content and relative quality traits in wheat: direct prediction based on reflectance spectra during filling and indirect estimation based on leaf nitrogen content at mid-filling stage.

Key words: Wheat, Grain protein, Grain quality, Canopy reflectance spectra, Leaf nitrogen content