Использование NDVI для определения содержания азота в растениях озимой пшеницы в условиях Ставропольского края

Abstract

Abstract. Lack of nitrogen leads to a decrease in yield and grain quality in winter wheat plants. Therefore, it is necessary to monitor nitrogen nutrition throughout the period of growth and development of plants, which will quickly assess the need for fertilizing to obtain high yields of quality grain. Therefore, the aim of the study was to establish the possibility of using the normalized difference vegetation index (NDVI) to control the nitrogen content in winter wheat plants in the Stavropol territory. Methods. The work was performed in federal state budgetary scientific institution “North-Caucasian Federal Agricultural Research Centre” at the production of winter crops. Selection of plant samples (sheaf material) was carried out according to the generally accepted method. Repeated – 4x. Determination of the chemical composition of plant organs was carried out by the method of V. T. Kurkaev with co-authors, and the content of chlorophyll – Milaeva and Primak. Results. Since the quality of winter wheat grain directly depends on the nitrogen supply of plants, the relationships between the nitrogen content in winter wheat plants and the values of the vegetation index NDVI were studied. High correlation coefficients between these indicators are obtained. Thus, the average of Rcorr fields.in 2012 it was equal to –0.89, and in 2013 and 2014 –0.82. In addition, due to the dependence of nitrogen content on the amount of chlorophyll, it was possible to analyze the correlation between these indicators and NDVI fields, which showed that a stable relationship (inverse) is observed in the case of the amount of chlorophyll per unit biomass (mg/g), which is estimated on average at –0.79. The interrelation between grain quality and earth remote sensing data is revealed. It is most clearly seen in the case of the maximum and average NDVI for the period from the resumption of spring vegetation to full ripeness of winter wheat. Scientific novelty. For the first time in the conditions of unstable humidification of the Stavropol territory, a high inverse correlation between the vegetation index NDVI and the nitrogen content in winter wheat plants was determined, which on average is estimated by the correlation coefficient equal to –0.84.