The effects of pre harvest oxalic acid applications on fruit quality of aprikoz and roxana apricots

This research was carried out to determine the effect of pre-harvest oxalic acid (OA) treatments on the fruit harvest quality of Aprikoz and Roxana apricots. Different doses (1, 2, 4 and 8 mM) of oxalic acid and Tween-20 (0.01 %) (as a surfactant) were sprayed on apricot trees as well as distilled water with Tween-20 (control group) 7 days before commercial harvest. Fruit width, fruit length, fruit weight, fruit firmness, fruit skin color, soluble solid content, titratable acidity, respiration rate, ethylene production and total carotenoid content were measured at the harvest time. The effects of OA treatments on fruit width, fruit length and fruit weight were noticeable. The doses of 2 mM in Aprikoz and 4 mM in Roxana was maintained the fruit firmness compared to control group. 2 mM (Aprikoz) and 4 mM (Roxana) OA treatments was the most effective treatment for soluble solid content and titratable acidity. OA treatments were positive effects on fruit skin color. All OA treatments reduced the ethylene production of apricots compared to control group. The highest carotenoid contents in Roxana were obtained from 4 mM and 8 mM OA treatments, while the lowest values were found in 1 mM OA treatment.