Tree Age and Harvesting Season Affected Physico-chemical and Bioactive Compounds of Elite Type of <i>Gunda Gundo</i> Orange (<i>Citrus Spp</i>) in the Northern Ethiopia

Marketability and nutritional content are critical factors that need to be considered when a quality of orange fruit is assessed. Among the many affecting quality, tree age harvesting season crucial once; however, remained unmapped. Thus, this study was aimed explore due differences in season. Three trees groups (young = 10 16, moderate 20 27 old greater than 30 years) grown at Gunda Gundo monastery its surroundings, northern Ethiopia harvested October December. The physico-chemical antioxidant contents were characterized during two consecutive years (2017–2018). R software (R version 3.6.2) used for analysis. highest single weight 218.71 g, peel thickness (3.6 mm) pH (3.73) obtained from young 2017. Total soluble solid 13.4° Brix recorded 2017, while 13.3° older harvest 2018. High rag mass 41.78% 2017 38.04% December 2018 fruits trees. vitamin C (53.95 mg 100 ml−1) total sugar (11.1%) trees; juice (52.04%) age; phenolic (9.15 mgGAEg−1), iron-reducing power (54.2 mgAAEg−1), (26.55 mgBHTg−1) lower DPPH EC50 value (1.5 obtained. This experimental results show had high activity.