An improved method and its application for agricultural drought monitoring based on remote sensing. Evaluation of Drought Tolerance and Fertility Traits for Rice Maintainer Lines Extensively Used in China The response of three crop drought indices to spring wheat water stress over semi-arid region in northwest China Effects of nitrogen fertilization on crop water stress index ofsummer maize in red soil Fertility Responses to Drought Injury at Booting Stage of Rice Maintainers and Remedy Effects of Water Complement