Temperature Treatments on Postharvest Handling of Small Onion (Allium cepa L. var. aggregatum Don.)

Studies on the effect of different temperature treatments on packing and storage methods in onion (Allium cepa L. var. aggregatum Don.) cv. CO On 5 at College orchard, Tamil Nadu Agricultural University, Coimbatore were temperature during 2008-2010. The experiment was laid out in a factorial completely randomized design (FCRD) with eight treatments and three replications. Pre-harvest sprays were done by using Maleic hydrazide @ 2000ppm + carbendazim @ 1000ppm and the harvested onion bulbs were cured with 2cm neck length packing and storage treatments were subjected to viz., jute bags and kept in room temperature (T 1 ), packing in nylon net bags and kept in room temperature (T 2 ), packing in perforated plastic crates and kept in room temperature (T3 ), packing in bamboo baskets and kept in room temperature (T 4 ), spreading of bulbs in ventilation storage (T 5 ), spreading of bulbs in cold storage at 15 o C (T 6 ), spreading of bulbs in cold storage at 20o C (T 7 ) and spreading of bulbs in room temperature - Control (T 8 ). Among the different packing and storage treatments, the lowest physiological loss in weight (5.18 %), sprouting (0.62 %), rotting (0.64 %), rooting (0.00 %) and the highest sulphur (0.704 %), pyruvic acid (2.53 μmol g -1 ) and ascorbic acid (10.24 mg 100 g -1 ) contents and the highest shelf life (up to 6 months) were observed in spreading of bulbs in ventilation storage (T 5 ) compared to control (T 8 ).