Effect of plant growth regulators on postharvest quality of banana (Musa sp. AAA Berangan)

Banana is a climacteric fruit that has high rate of deterioration which contributes to high postharvest losses. These losses might be due to improper postharvest handling and storage and occurs at any point in banana supply chain. These serious postharvest losses could be reduced by adopting one of the feasible postharvest management practices which include applying plant growth regulators (PGRs) such as gibberellins (GA3) and auxin (IAA). The treatments were 150 mg L-¹GA3, 5.71 x 10-7 mg L-¹ IAA, the combination of IAA and GA3 (2.85 x 10-7 mg L-¹and 75 mg L-¹respectively) with three replications. The parameter assessments were internal ethylene production, percentage weight loss, fruit firmness, total soluble solids (TSS) and starch pattern index (SPI). The GA3-treated-fruit resulted in delayed production of ethylene (day 7) whereas control fruit and combination of IAA and GA3-treated-fruit showed the earliest production of ethylene which was on day 2. The earliest occurrence of climacteric peak was closely related to the rapid ripening process bringing about speedy changes in colour, texture, aroma, chemical composition and respiration rate of Berangan banana. In addition, GA3-treated-fruit experienced SPI score 3 for the whole experimental period which was reflected by the delay in peel colour changes, fruit firmness while maintaining other quality attributes. As a conclusion, GA3 was able to delay the climacteric peak of Berangan banana and also retard the peel color changes, fruit softening and extend its shelf life up to 16 days.