Evaluation of granulation and quality parameters of Monte Parnaso late navel orange from South Brazil

ABSTRACT

This work aimed to evaluate granulation incidence and severity and quality parameters of ‘Monte Parnaso’ navel orange in different harvest and collection dates. The 2018 and 2019 harvests were evaluated, and the collection dates of 0, 15, 30, and 45 days after commercial collection. The evaluated parameters were granulation incidence and severity, fruit weight, longitudinal and transversal diameters, peel thickness, juice content, soluble solids content, titratable acidity, SS/TA ratio, and ascorbic acid content. The results underwent chi-squared to evaluate granulation incidence and severity, and analysis of variance for the quality parameters; occurring statistical difference, the means were compared by Tukey’s multiple range test at 5 % probability. Granulation incidence and severity were not related to collection time. Only severity was related to the harvest. The quality parameters were influenced significantly only by the harvest factor, with exception of the parameters of titratable acidity, influenced only by the factor collection date, and ascorbic acid content, which presented interaction between factors. Granulation incidence and severity were higher in the larger and heavier fruits. The frequency of fruits in the categories of higher severity (> 50 %) was higher in the 2018 harvest than in the one of 2019.

Keywords:
Citrus sinensis (L.) Osb.; Poncirus trifoliata (L.) Raf.; Citrus physiology; Fruit quality.