With the ready availability of molecular technology comes the opportunity to study the genotype to phenotype relationship of complex physiological processes.  The physiology of growth has been studied extensively, but little is known about the genetic regulation of growth.  As a means of closing the genotype to phenotype gap associated with growth, a study of maize kernel growth was conducted in a sample of 140 test-crossed double haploid lines along with eight commercial hybrids and the parents of the doubled haploids..  Biomass and moisture accumulation were evaluated in developing kernels sampled at intervals of approximately 25 growing degree units (GDU) beginning with 200 GDU after pollination and ending 200 GDU after physiological maturity.  The data analyses are being conducted in three stages.  The first is selection of appropriate models to describe biomass and moisture accumulation.  From among possible growth models Gompertz, Chanter and Richards functions appear to fit the data in biomass contents in the check hybrids and parents.  Because the first derivatives of Gompertz, Chanter and Richards functions appear to provide reasonable models to describe the data in moisture content, the second stage of analyses will be to determine if there are models that functionally connect biomass and moisture accumulation.  The third stage will attempt to associate QTL with variability in estimates of the parameters describing the biomass and moisture accumulation.