Description of the peach fruit growth curve by diphasic sigmoidal nonlinear models

Abstract The aim of this study was to describe the growth curve “Aurora 1” peaches using fruit height and diameter data over time through diphasic sigmoidal models constructed from eight combinations following models: Brody, Gompertz Logistic. Data were obtained an experiment carried out in 2005 municipality Vista Alegre do Alto, São Paulo, Brazil. parameters adjusted by least squares method Gauss-Newton algorithm implemented R software. Assumptions normality, homogeneity independence residues verified based on Shapiro-Wilk, Breush Pagan Durbin-Watson tests, respectively. goodness fit according corrected Akaike information criterion (AICc), residual standard deviation (RSD), asymptote adjustment index (AI) nonlinearity measures. All for both variables met assumptions homoscedasticity errors. In addition, all them present good quality data, since they presented AI values close one low RSD non-linearity However, double (GG) Logistic + (LG) presented, respectively, best relation other models. It could be concluded that evaluated showed can used “Aurora-1” peaches, criteria. it is important highlight GG LG selected peach fruits, with maximum expected 63 mm 48 diameter.