Post-harvest application of putrescine to extend shelflife and quality of tomatoes during cold storage

Abstract

Putrescine (PUT) is a polyamine responsible for plant growth and development, fruit ripening, stress response, senescence and in higher quantities to maintain postharvest quality in vegetables. Tomato (cv. Punjab Ratta) fruits of uniform size and weight were picked at mature green to breaker stage from unreplicated crop grown during 2012-13 and 2013-14 at Vegetable Research Farm, Punjab Agricultural University, Ludhiana, Punjab, India and treated with putrescine at 1 mmol/L, 2 mmol/L and 3 mmol/L concentrations and untreated control corresponding to T1, T2, T3 and T4 respectively. After imposing the treatments, tomato fruits taken in plastic crates and stored at 13±2oC and relative humidity of 85-90% for further storage studies. To find out the effect of post-harvest application of putrescine on tomato during storage, fruits were analysed at 5 day interval i.e at 1st, 6th, 11th, 16th, 21st and 26th day after treatment for various quality parameters and average of two year readings was presented. At 26th day after treatment, least physiological loss in weight % was observed in the T3 treatment (PUT at 3 mmol/L) while, at 16th day after treatment, fruits in T2 treatment were recorded with hue angle of 62.050 which was above the hue angle of acceptable red stage (550) compared to T1, T3 and control. Treatments T2 and T3 retained the decay% below threshold (10%) levels upto 16th (8.18% and 6.01% respectively) day after treatment than untreated control. However, all putrescine treatments showed higher titratable acidity compared to control at the end of the storage.