Effect of Gibberellins (GA3) on the postharvest life and quality of Papaya fruits under ambient storage conditions

Thumbnail Image
Journal Title
Journal ISSN
Volume Title
Papaya is an important fruit crop in the tropics. The crop however, has a short shelf-life leading to high postharvest losses in papaya growing areas in the Akuapim South Municipality. The study was in two phases including survey and laboratory analysis. The survey was conducted on famers in the Akuapim South Municipality in order to identify the challenges they encounter during papaya production. Majority of the famers mentioned short shelf-life as the main problem they encounter during papaya production even though they have other challenges in the production of papaya fruits in the study area. The research attempted to mitigate this problem by applying a postharvest technology as a way of prolonging the shelf-life of the crop. The laboratory work was carried out at the Department of Horticulture, Kwame Nkrumah University of Science and Technology (KNUST) to determine the effect of GA3 on the postharvest life and quality of papaya fruits under ambient storage conditions in a 2 × 4 factorial arrangement in completely randomized design with three replications. Four rates of GA3 were applied on the papaya fruits at 0mg/litre, 100mg/litre, 200mg/litre and 300mg/litre. It was observed that of all the nine quality characteristics, effect of papaya varieties (colur, shelf-life, weight loss, moisture content and total soluble solids) were significantly different (p=0.01). However, effect of variety on pH, firmness, total titratable acidity and sugar/acid ratio did not show significant differences (p>0.01). Shelf-life of papaya varieties were significantly different (p=0.01). Kapoho had a mean of 11 days to ripen whilst Sunrise recorded a mean of 10 days to ripen. The four GA3 concentrations recorded significant differences on all the nine properties of the papaya fruits. Papaya fruits stored longer as the concentration were increased. Gibberellins concentrations at 0mg/litre had the least mean number of 6 days to ripening whilst the papaya fruits treated with the highest concentration of 300mg/litre had the highest mean number of 15 days. Also, sensory attributes of papaya fruits were highly accepted by the ten (10) panelists. Fresh papaya fruits (control) were served jointly with the gibberellins treated papaya fruits after the storage period to the panelists for their assessment and evaluation. Significant differences (p=0.01) were observed for pulp colour, aroma, taste, mouth feel and general acceptability. There was no significant difference (p>0.01) between the control and the gibberellins concentration of 300mg/litre. Overall, papaya fruits applied with gibberellins concentration of 300mg/litre was effective in prolonging the shelf-life of both types of papaya under ambient storage conditions.
A thesis submitted to The School of Research and Grduate Studies, Kwame Nkrumah University of Science and Technology, in partial fulfilment of the requirements for the award of Master of Philosophy (Mphil. Postharvest Technology) Degree,