MODEL OF THE DEVELOPMENT AND BULKING OF POTATOES (SOLANUM-TUBEROSUM-L) .2. PREDICTION OF DISTRICT COMMERCIAL YIELDS

A model (Mi) of the development and bulking of potatoes was derived from data relating to individual crops grown under high quality management. Since practical and theoretical difficulties prevented direct adoption by a population of growers in a district under average weather conditions, an attempt was made to derive alternative parameter values, for a version called Md, using data on the typical yield and timing of production activities for 41 district crops grown in Australia together with average weather data for these districts. It was found that the growth of the district crops could be explained by the relationships used in Mi provided the form of one of the relationships was modified, namely that for the maximum bulking rate. These findings provided validation of the concepts on which Mi was based and implied that the relationships used in Mi were not location- or season-specific. The respective roles envisaged for Mi and Md are briefly discussed. © 1979.