Quality of seedless watermelon cultivated under different doses and phosphorus application forms

摘要

Effects of doses and phosphorus application forms were studied on the postharvest quality in seedless watermelon hybrid 'Style'. For this, an experiment was conducted in Upanema/RN, Brazil, during the period of September to December 2013, in a randomized block at factorial scheme 5×2 constituting of five phosphorus doses applied in foundation (0, 76, 168, 275 and 397 kg ha-1 of P2O5) and foundation + fertigation (0+50, 26+50, 118+50, 225+50, 347+50 kg ha-1 of P2O5) with four replications. Fruit harvested at commercial maturity (78 days after sowing) were evaluated by average fruit weight (AFW), ?pulp firmness (PF), chroma index, hue angle, soluble solids content (SS), titratable acidity (TA), maturation index (MI), total phenols content (TP), vitamin C (VC), total sugars content (TS), reducing sugars content (RS) and pH. Among the quality parameters evaluated phosphorus application forms did not affect physical characteristics of fruit, but combination of application via foundation + fertigation increased VC, TS and MI. There was interactive effect of dose and phosphorus application form for the SS, TA, pH and TP. The dose of 50 kg P2O5 ha-1 applied only in fertigation significantly increased values of SS, TA and TP. It is concluded that low doses of P in cultivation and its application via foundation and fertigation improved the main quality characteristics of ‘Style’ watermelon.