Inversion of foliar biochemical parameters at various physiological stages and grain quality indicators of winter wheat with canopy reflectance

Canopy reflectance data selected at key growth stages of winter wheat were analysed. Regression equations between foliar total nitrogen content and other foliar biochemical concentrations, dried biomass indices, and grain quality indicators were established. The results showed that there were robust correlations between foliar total nitrogen content and other foliar biochemical concentrations, dried biomass indices, and grain quality indicators. The predictions of soluble sugar content, foliar water content, stem water content, foliar starch content, foliar dried weight, plant dried weight, and Leaf Area Index (LAI), etc. by foliar total nitrogen content were successful and feasible. The predictions of grain protein and dry gluten content by foliar total nitrogen content at anthesis were surprisingly good. The wavelength bands related to foliar total nitrogen content selected by regression equation were located at 1000-1140 nm and 1200-1300 nm.