Physico-chemical evaluation of red-fleshed dragon fruit (Hylocereus polyrhizus Britton and Rose) as influenced by potassium fertilization

Potassium (K) is an important, essential nutrient because of its effects on quality factors and the fact that it plays an important regulatory role in various key physiological processes (i.e., translocation of sugars and formation of carbohydrates, protein synthesis and regulation of particular enzymes). Red-fleshed dragon fruit (Hylocereus polyrhizus) has high functional potential and is in demand in the market.
This study aimed to evaluate the physico-chemical properties of freshly picked fruit at 38 days after anthesis (DAA) as influenced by five different potassium levels imposed as fertilizer treatments: T1) N₆₀P₁₂₀K₆₀; T2) N₆₀P₁₂₀K₁₂₀; T3) N₆₀P₁₂₀K₁₈₀; T4) N₆₀P₁₂₀K₂₄₀; and T5) N₆₀P₁₂₀K₃₀₀. Significant differences were observed in percent pulp and peel, equatorial diameter, number of fins and fin length and base width.
Positive differences in pulp total soluble solids concentration (°Brix) and pulp acidity (pH) were also recorded.
Application of 60-120 kg K produced the highest % pulp, while fruits applied with 300 kg K yielded the highest percent peel relative to other treatments.
Treatment 1 (60 kg K) produced the longest fin length (42.33 mm) and greatest fin base width (14.78 mm), while T3 gave the highest equatorial length (92.22 mm). Application of 180 kg K ha^‑1 (T3) gave the highest total soluble solids concentration (13.40 °Brix) and pulp acidity (pH 5.23). The results indicate that most of the physical and physico-chemical parameters were influenced positively by the application of 180 kg K relative to the other rates that were applied.

III Asian Horticultural Congress – AHC2020

J.N. Magallanes, A.B. Gonzaga, N.R. Gonzaga

potassium, physico-chemical evaluation, postharvest, dragon fruit

https://doi.org/10.17660/ActaHortic.2021.1312.47