Relationship between minerals and physicochemical parameters with fruit quality in 'Rocha' pear orchards

Aims At the same location, variability among orchards may be high, which is reflected in fruit quality, and it may be associated mainly with growers' practices. This study aimed to identify physicochemical variability within pears (Pyrus communis L. cv 'Rocha') from three orchards from the same location and under the same climate conditions and correlate it with mineral composition. Methods Fruits from three orchards harvested at the optimal harvest time were characterized during ripening under shelf-life conditions of 7 d at 20 +/- 2 degrees C. The analyses performed included ethylene production, respiration rate, fruit quality (firmness, skin colour, soluble solids, and titratable acidity), macro and micronutrients, ethylene biosynthesis enzymes, esters, sugars, and organic acids. Principal component analysis was used to show the variability among fruits from the three orchards and to correlate the differences with the fruit mineral composition. Results Phosphorus (P) and potassium (K) were significantly correlated with esters and soluble solids content (r similar to 0.4 for both minerals). Fruits with higher P and K concentrations were associated with a potential over-ripeness pattern considering their higher acetate production and lower sugar concentration. Esters, soluble sugars, and sorbitol were the dominant fruit quality factors responsible for the differences among the orchards. Conclusion With this study it is expected that a better understanding of the relationship between specific minerals and quality parameters can help growers manage their orchards more efficiently and achieve consumers' quality demands.