Nutrients in the field and crop growth information require nutrient diagnosis. There are many methods for diagnosis. The traditional method of diagnosis of nutrients in crops is high in accuracy, but it is more time consuming, costly, and if there is a large area for nutrient diagnosis. It is not suitable. In recent years, spectrum-based crop nutrient diagnosis technology can achieve real-time crop nutrient acquisition. This study analyzed the changes of cotton spectral parameters NDVI, RVI and SPAD in the course of childbearing under different water and nitrogen conditions in order to provide technology for cotton water and nitrogen diagnosis. stand by. Crop nutrient diagnostic instruments are more effective in this application. Plus Wechat controls more relevant information: The film of the soft film lamp box is a high-grade new environmental protection material. It is flexible in texture and rich in color, and can be stretched at will. It completely breaks through the limitations of traditional light boxes in modeling, color, small piece assembly, and is rich in color. The ultra-thin soft film lamp box perfectly combines the light guide plate and the soft film together, making it ultra-thin and more delicate. Slim Fabric Light Box,Led Light Box,Lighting Box,High Brightness Light Box Guangzhou Jinshiming advertising equipment Co., Ltd , https://www.gzjsmad.com
Under the same irrigation condition, NDVI showed an increasing trend with the increase of nitrogen application rate. In the growth process of cotton, the NDVI in the early growth stage does not increase significantly with the amount of nitrogen applied. With the progress of the birth process, the effect of nitrogen on NDVI gradually becomes apparent. The results of data processing under the W2 and W3 moisture treatments show that From 89 days after emergence (full flowering period) to 110 days after emergence (flowering and bolling period), the difference in NDVI between treatment sites under different nitrogen application rates was extremely significant, while the difference between W0 and W1 conditions was relatively small. Nitrogen is an important component of the crop's green organ's chlorophyll. Nitrogen application can promote the vigorous growth of the aboveground part of the crop. Nitrogen fertilizer gradient treatment affects the growth of the cotton canopy, NDVI also appears to be different, and water is used as a plant to absorb and utilize nutrients. The important medium influences the absorption and utilization of nitrogen nutrition, which is mainly reflected in the same nitrogen application on the NDVI of cotton canopy under W0 and W1 conditions is less than W2 and W3 treatment.
The crop nutrient diagnostic apparatus has studied the "low-high-low" variation of the cotton canopy NDVI during the whole growth period, which is similar to the results of previous studies. During the growth period of cotton, RVI showed a trend of “high-low-highâ€, which was contrary to the change rule of NDVI. The SPAD value showed the same change trend as NDVI during the growth period of cotton, and it was lower at 52 days after emergence, and then gradually increased. The peak value of full flowering period showed a gradual decrease trend. 
Crop nutrient diagnostic apparatus for field and crop nutrient application