Yellow Pitahaya (Selenicereus megalanthus Haw.) Growth and Ripening as Affected by Preharvest Elicitors (Salicylic Acid, Methyl Salicylate, Methyl Jasmonate, and Oxalic Acid): Enhancement of Yield, and Quality at Harvest

Abstract

Yellow pitahaya (Selenicereus megalanthus Haw.) is an exotic fruit with great potential for exportation in Ecuador. The research was carried out with the objective of evaluating the fruit growth and ripening as affected by four elicitors: salicylic acid (SA), methyl salicylate (MeSa), methyl jasmonate (MeJa), and oxalic acid (OA), all of them at 1, 5, and 10 mM concentration, compared with untreated plants (control). For each elicitor, nine plants were selected, and on each plant, three fruits were marked to follow up the growth by measuring polar and equatorial diameters. At harvest, yield (kg plant−1 and number of fruits plant−1), fruit weight, percentage of pulp and skin, total soluble solids (TSS), titratable acidity (TA), and firmness were determined. Treated plants enhanced fruit size, crop yield, and fruit weight compared with control fruits, although results depended on the elicitor tested and applied doses. The highest and lowest TSS were found in 10 mM MeSa and 5 mM MeJa-treated fruit, respectively, while the highest TA content was shown in 5 mM SA. Firmness was only enhanced in MeJa-treated fruits. Overall, results suggest that preharvest use of elicitors could modulate the pitahaya ripening and could improve quality attributes at harvest.

Preharvest Elicitors as a Tool to Enhance Bioactive Compounds and Quality of Both Peel and Pulp of Yellow Pitahaya (Selenicereus megalanthus Haw.) at Harvest and during Postharvest Storage

“…In our previous report on pitahaya [29], preharvest SA and MeSa applied at 1, 5 and 10 mM increased TSS with the doses of 1 and 10 mM of MeSA and SA at 1 and 5 mM. In addition, the elicitors increased yield productivity and fruit weight.…”

“…Treatments were applied with a frequency of 15 days, starting at 57 days after full blossom (DAFB) and after 71, 86 and 102 DAFB, while the harvest was carried out at 126 DAFB. The elicitors were methyl salicylate (MeSa) and methyl jasmonate (MeJa) (both at 0.1 mM), while salicylic acid (SA) and oxalic acid (OA) were applied at 5 mM, based on previous experiments (Erazo-Lara et al, 2024) [29]. Treatments were performed by spraying 1.5 L per plant with freshly prepared solutions of MeSa, SA, MeJa and OA (purchased from Sigma-Aldrich, Madrid, Spain) containing 0.5% Tween-20 as the surfactant.…”