Physical and chemical evaluation of papaya cv. Tainung n.1 fruits fertirrigated with different combinations of nitrogen sources

Abstract

The present work aimed to evaluate physical and chemical parameters of papaya fruit under two sources of nitrogen (ammonium sulfate and calcium  nitrate) during the crop cycle. The experiment was developed in an experimental field of Embrapa Cassava and Tropical Fruits, in the municipality of Cruz das Almas, Bahia State. Treatments were: T1 – application of ammonium nitrate during 100% of papaya cycle, T2 – application of ammonium nitrate during 75% of cycle and calcium nitrate during the remaining 25%, T3 – application of ammonium nitrate during 50% of cycle and calcium nitrate during the remaining 50%, T4 – application of ammonium nitrate during 25% of cycle and calcium nitrate during the remaining 75%, T5 – application of calcium nitrate during 100% of papaya cycle. The experimental design was in random block design, with five replicates. Physical characteristics (length and outer diameter, cavity diameter, pulp thickness, pulp strength) and chemical characteristics (titratable acidity – TA, soluble solids – SS, SS/TA ratio and pH) of fruits were
evaluated. The different sources of nitrogen and their combinations had significant influence on the pulp strength, titratable acidity and SS, SS/TA ratio. Regarding the physical parameters, the use of ammonium sulfate all over the cycle is the best alternative, however, better chemical fruit quality is obtained with the application of calcium nitrate for up to 50% of the cycle.