Studies on pre and post-harvest treatments for extending shelf life in onion – A review

In India, presently about 35 to 40 per cent of the onion is estimated to be lost as postharvest losses during various operations including handling and storage. Pre-harvest sprays of growth regulators viz., cycocel, ethylene compounds and fungicides play a crucial role in enhancement of shelf life in onion. The curing techniques like neck cut in onion bulbs and exposure to onion bulbs in gamma radiation for storage are proved to be useful techniques in delaying sprouting and their subsequent deterioration resulting in improved shelf life. Packaging and storage techniques also influence the shelf life of onion bulbs during storage. There is a sequence of physiological and biochemical changes occur in onion bulbs during above post harvest handling operations. The literature pertaining to the above aspects during post harvest handling and storage of onion and garlic bulbs are reviewed in this paper.