[Study on the difference in canopy spectral reflectance and chlorophyll content of spring wheat at jointing stage in different land].

Taking chlorophyll content, seedling height, blade width and canopy spectral reflectance of spring wheat at jointing stage in different lands as data source, by analyzing the correlations between canopy spectral reflectance and chlorophyll content, making regression analysis for red edge inflection points of canopy spectral reflectance and chlorophyll content of spring wheat, the chlorophyll content monitor models of irrigated and dry land were established respectively. The results showed that there is a significant difference in chlorophyll content of spring wheat, with chlorophyll content of irrigated land much higher. Although there is a good correlation between wheat canopy spectral reflectance and chlorophyll content in the two lands, the correlation of dry spring wheat is lower than irrigated land in visible light and near infrared band. In the visible region, dry spring wheat canopy spectral reflectance is higher, inverse in near-infrared region. Due to high soil moisture, the dry-land spring wheat grows well and there is little difference from irrigated land. The monitor model of red-edge inflection points of canopy spectral reflectance and chlorophyll content of spring wheat at different lands showed that irrigated land wheat is available for linear model, The estimated precision is 94.06%, but dry land is suitable for binomial model, The estimated precision is 97.15%, 10.48% higher than linear model.