NIR measurement of nitrogen content in beet leaves

For a number of years NIR spectroscopy has acquired increasing importance, in both beet and sugar production, for assessing raw material and process c ontrol. In a further extension of these applications, NIR could be used for evaluat ing total nitrogen content in the leaves of growing beet. Previous investig ations have emphasized the possibility of correlating the nitrogen content in leaves with the available nitrogen content of the soil, Analysis of leaf nitrogen status makes it possible to advise farmers whether use of fertili zers would be worthwhile during growth of the plants. Such a practice shoul d avoid problems due either to inadequate supply of nitrogen (poor developm ent), or to oversupply (pollution and reduction in the beets' technical val ue). Experiments described here show that NIR spectroscopy could replace traditi onal methods for determining leaf nitrogen contents. This would have two ma jor advantages: the use of chemical reagents would be eliminated, and a gre at deal of time would be saved - which is important given the large numbers of samples that often have to be analyzed within a very limited time.