According to the results of research, for the first time a new class of specialized indices for UAVs has been proposed, which are able to identify the technological nature of stress for winter rape in the optical range. It was found that the RLrg index, based on the use of red and green channels, provides selectivity for the identification of leaves with abnormal color, soil and green leaves of plants. Due to the use of red and green channels, RLrg can potentially be adapted for the most common industrial multispectral equipment. The index RLrgb = 2R - G - B, with a lower sensitivity to the identification of red leaves and soil, is able to separately identify red and yellow leaves, as well as the difference between the green leaves of affected and healthy rapeseed leaves. The aim of the work was to develop an index based on the results of analysis of digital images with high resolution, obtained using UAVs, to identify technological stresses. In field studies, it was found that the affected areas of the plant have an abnormal color of the two lower leaves, namely yellow and red. The use of monochromatic images of each of the spectral channels was insufficient to isolate such leaves. Therefore, to identify the affected plants, it was proposed to use the image of the object, based on the ratio of several channels simultaneously, which allowed to distinguish between affected and healthy plants, soil, plant remains
rapeseed, technological stress, plant nutrition, indication indices, UAV