Diagnosis of the Npk Requirements of Sugarcane Plant Age and Season Using Beau

Recently Beaufils published a monograph entitled Diagnosis and Recommendation Integrated System (DRIS) in which he presented complete details of his experimental approach and plantlenvironment calibration technique for the first time. One of the cardinal points of this diagnostic technique is that it should be applicable to a particular crop grown at any place at, any stage of its development. The concepts of this experimental approach and diagnostic technique were originally developed for rubber trees in Vietnam; they were then adapted to maize in the southern part of Africa. After further expansion to potatoes, application of these concepts is now being developed for sugarcane. In this paper preliminary observations on the sensitivity and general applicability of this system to sugarcane are presented. From data on leaf composition and yield obtained from growers in the South African Sugar Industry by means of a survey, a provisional standard chart for the determination of N P K requirements of sugarcane has been established. An evaluation of this chart has been made by application to data obtained either from the literature or the S.A. Sugar Association Experiment Station, Mount Edgecombe. At this early stage it appears that one can reasonably expect an improved sensitivity in the diagnosis of N and P requirements of sugarcane as well as the possibility of diagnosing N P K requirements at any stage of development irrespective of moisture status, season and variety.