[Hyperspectral characteristics of spring maize from jointing to silking stage under drought stress]

By monitoring hyperspectral characteristics of spring maize from jointing to silking stage under different drought stress in Jinzhou of Liaoning, China, its spectral characteristics of visible light, red edge region and near infrared were researched, and the correlation of spectral reflectivity of different wavelength with soil moisture was analyzed. The results show that during the jointing to siking stage, the spectral reflectivity of 350-710 nm has significant negative correlation to soil moisture of 0 and 20 cm depth, but the spectral reflectivity of 710-1 300 nm has positive correlation to soil moisture of 0, 20, 40 and 60 cm, and the significant correlation is at 40 cm depth. The spectral reflectivity of red edge region (680-760 nm) which is relatively sensitive and stable, can better reflect the growth status of the plant, and the reflectivity variation per unit wavelength in this region increased at first and then decreased. The trend of polynomial regression curve of red edge parameters and soil moisture of different depth (0-60 cm) is similar, which shows that soil moisture of 0 and 20 cm increased at first and then decreased, but that of 40 cm and 60cm was opposite.