The use of the nonlinear models in the growth of pears of ‘Shinseiki’ cultivar

• Main Authors: Thais Destefani Ribeiro, Taciana Villela Savian, Tales Jesus Fernandes, Joel Augusto Muniz
• Format: Article
• Language: English
• Published: Universidade Federal de Santa Maria 2017-12-01
• Series: Ciência Rural
• Subjects: Biometric measurements; Asian pear; model Gompertz; logistic model
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782018000100201&lng=en&tlng=en

ABSTRACT: The goal of this study was to elucidate the growth and development of the Asian pear fruit, on the grounds of length, diameter and fresh weight determined over time, using the non-linear Gompertz and Logistic models. The specifications of the models were assessed utilizing the R statistical software, via the least squares method and iterative Gauss-Newton process (DRAPER & SMITH, 2014). The residual standard deviation, adjusted coefficient of determination and the Akaike information criterion were used to compare the models. The residual correlations, observed in the data for length and diameter, were modeled using the second-order regression process to render the residuals independent. The logistic model was highly suitable in demonstrating the data, revealing the Asian pear fruit growth to be sigmoid in shape, showing remarkable development for three variables. It showed an average of up to 125 days for length and diameter and 140 days for fresh fruit weight, with values of 72mm length, 80mm diameter and 224g heavy fat.