SCALES - A COMPUTER-PROGRAM TO CONVERT AMONG 3 DEVELOPMENTAL STAGE SCALES FOR WHEAT

The Haun, Feekes, and Zadoks-Chang-Konzak developmental stage scales a re often used to report phenological information for wheat (Triticum a estivum L.) development. Agronomists familiar with one of these scales may have only a passing acquaintance with developmental scales other than the one they consider most appropriate for their purposes. This m akes review and interpretation of the literature more difficult. Altho ugh wheat development models often report phenological results, they g enerally use no more than one scale. For these reasons, and because th ere is not a simple numeric correspondence among the three scales, a c omputer program to convert among them is a useful tool. SCALES is a th ree-module FORTRAN program that relates the three scales based on publ ished descriptions. The interactive user interface module requests an input scale value and minimal additional information, which the conver sion module uses to determine values for the remaining two scales via a dichotomous key. The output module writes the conversion results to the monitor. SCALES may be used independently for comparing phenologic al data based on different developmental scales, or the conversion mod ule may be incorporated into computer models to provide output of deve lopmental stage information for the simulation.