Abstract:
Sweet orange (Citrus sinensis L.) is one of the highly demanded commercially sub-tropical fruit in the world and it is also an important fruit in Eritrea. Post-harvest handling of sweet oranges in Eritrea is very poor and this has resulted in great losses. Sweet orange of Eritrean lowlands (particularly Zoba Anseba) reach ripe stage while fruits are still green in color. The lack of colored fruits is due to the relatively high temperature in this region during harvesting period, which results to low demand and low prices in the market. The objective of this research was to find out effects of ethrel concentrations and packaging on de-greening (color development) and quality of sweet orange fruits. The experiment was conducted at Horticultural Science laboratory (Dark room) with cooling system (fan) during the period from 14th - 29th of November 2020. Light green sweet orange fruits were treated with ethrel at two concentrations (2ml/l and 3ml/l) and some of them left untreated. On the other hand, fruits were packaged individually in sealed-intact polyethylene (transparent one) and some of them left unpackaged plus a control (untreated and unpackaged). Six treatments were arranged in a Complete Randomized Design (CRD) with three replicates and four fruits/treatment/replicate. Results showed treated sweet orange fruits with ethrel at both concentrations significantly accelerate de-greening of fruit rind and developed uniform orange color compared to control fruits, which remained yellowish green. Packaged fruits recorded minimum weight loss (2.08 %) compared to the highest weight loss of unpackaged (13.13%). No change in TSS (%) and TA during storage of fruits. It is recommended to treat sweet orange fruits with ethrel at (2ml/l) and package them in sealed-intact polymeric polyethylene bag to obtain attractive appearance and good quality.Sweet orange (Citrus sinensis L.) is one of the highly demanded commercially sub-tropical fruit in the world and it is also an important fruit in Eritrea. Post-harvest handling of sweet oranges in Eritrea is very poor and this has resulted in great losses. Sweet orange of Eritrean lowlands (particularly Zoba Anseba) reach ripe stage while fruits are still green in color. The lack of colored fruits is due to the relatively high temperature in this region during harvesting period, which results to low demand and low prices in the market. The objective of this research was to find out effects of ethrel concentrations and packaging on de-greening (color development) and quality of sweet orange fruits. The experiment was conducted at Horticultural Science laboratory (Dark room) with cooling system (fan) during the period from 14th - 29th of November 2020. Light green sweet orange fruits were treated with ethrel at two concentrations (2ml/l and 3ml/l) and some of them left untreated. On the other hand, fruits were packaged individually in sealed-intact polyethylene (transparent one) and some of them left unpackaged plus a control (untreated and unpackaged). Six treatments were arranged in a Complete Randomized Design (CRD) with three replicates and four fruits/treatment/replicate. Results showed treated sweet orange fruits with ethrel at both concentrations significantly accelerate de-greening of fruit rind and developed uniform orange color compared to control fruits, which remained yellowish green. Packaged fruits recorded minimum weight loss (2.08 %) compared to the highest weight loss of unpackaged (13.13%). No change in TSS (%) and TA during storage of fruits. It is recommended to treat sweet orange fruits with ethrel at (2ml/l) and package them in sealed-intact polymeric polyethylene bag to obtain attractive appearance and good quality.