Influence of potassium fertilization on quality and antioxidant potential of sapodilla at different development stages

ABSTRACT The chemical composition and stage of maturation may interfere with harvest point of sapodilla depending on the destination of the fruit. This study aimed at evaluating the influence of potassium fertilization on quality and antioxidant potential of sapodilla at different development stages. The experiment was carried out on farm Norfruit, in Pau Branco, Mossoró, RN. The experimental design was completely randomized blocks in a 5 × 6 factorial scheme, consisting of five doses of potassium (0, 200, 400, 600, and 800 g K for plant) and six development stages, with five repetitions. The fruits were marked when reaching 10 to 15 mm in length, being collected and evaluated after 90, 120, 150, 180, and 200 days after being marked and when they were fully mature (after eight days of storage at 25 ± 2 °C and RH 58 ± 5%). Sapodilla can be harvested 200 days after full bloom, when it reaches its maximum size and presents adequate quality for consumption. The ripe sapodilla has higher concentration of sugar and lower concentration of bioactive compounds and antioxidant activity. The dose of 400 g of K per plant generated fruits of greater mass, with higher concentration of polyphenols and antioxidant activity. The antioxidant activity of sapodilla is more correlated with total extractable polyphenol concentration.