Journal of Scientific & Industrial Research Vol 73, November 2014, pp. 713-718 Salicylic acid pre-treatment alleviates chilling injury, preserves bioactive compounds and enhances shelf life of mango fruit during cold storage K Barman 1 * and R Asrey 2 *1 Department of Horticulture (Fruit and Fruit Technology), Bihar Agricultural University, Sabour, Bhagalpur, Bihar – 813 210, India 2 Division of Post Harvest Technology, Indian Agricultural Research Institute, New Delhi – 110 012, India Received 21 November 2013; revised 3 April 2014; accepted 8 August 2014 This study was conducted to investigate the effect of postharvest salicylic acid (SA) treatment on alleviating chilling injury (CI), preserving bioactive compounds and extending shelf life of mango fruit during low-temperature storage. Physiologically mature mango fruit (cv. Chausa) were immersed in 1 mM and 2 mM SA solutions for 5 min and then stored at 8±0.5ºC temperature and 90±5% relative humidity. Before taking observations, the fruit were subjected to exposure at 25±2ºC temperature for 3 days to simulate shelf life. The results showed that SA treatments were highly effective in alleviating CI (11-25% lower) in mango fruit. Among the treatments, 2 mM SA proved best in lowering weight loss, fruit softening, disease incidence, pectin methylesterase and polygalacturonase activities over control. Bioactive compounds like carotenoids, phenolics and antioxidant capacity were also maintained higher in SA-treated fruit. The findings confirmed that, SA (2 mM) can be potentially used as a pre-storage treatment during low-temperature storage of mango fruit. Keywords: Mango; Salicylic acid; Chilling injury; Antioxidant capacity; Enzyme activity. Introduction Mango (Mangifera indica L.) is one of the most popular fruit and commonly known as ‘King of fruits’ in Asian countries. Because of its delicious taste and pleasant flavor, it is ranked as one of the choicest fruits in the national and international market. Mangoes ripen and deteriorate very fast when stored at ambient temperature, which leads to reduction in shelf life. Therefore, low-temperature storage is necessary to slow down the metabolic processes and decay development but, when this fruit stored at temperature below 13ºC, it develops chilling injury (CI) which further limits its shelf life during low-temperature storage. The symptoms manifest as discoloration and pitting of the peel, sunken lesions, lenticels spotting, shrivelling, uneven ripening, poor color, off-flavor development and increased susceptibility to decay 1 . These lead to reduction in market value of the fruit. Salicylic acid (SA) belongs to a group of phenolic compounds that are ubiquitous in plants and is now considered as plant hormone 2 . It plays pivotal role in regulating a variety of physiological processes in plants. Recently, SA has also been reported to act as a key signal molecule for expression of multiple stress resistance in plants 3 . The effect of SA on delaying ripening, fruit softening and reducing disease incidence have been discussed by several researchers 3 .In recent years, a few studies have reported that pre-storage SA treatment alleviates CI in fruit during cold storage 4,5,6 .Considering the commercial importance of the fruit and its postharvest problem during low- temperature storage, we investigated the effect of SA in alleviating CI, extending shelf life and preserving fruit quality during cold storage. Materials and methods Plant materials and treatments Mango fruit of cv. Chausa were harvested at physiological maturity stage (light cream pulp with 8–10ºBrix total soluble solids) from an orchard located at IARI, New Delhi (India). After selecting uniform sized healthy fruit, they were randomly divided into 3 lots each of 216 fruit for the following treatments in triplicate (72 fruits per replicate): control (treated with distilled water), SA at 1mM and 2 mM concentrations. Fruit were treated by dipping in 20 l solution of SA containing Tween-20 (2 g L -1 ) as surfactant, at 25ºC for 5 min. They were then air-dried at room temperature and stored in a temperature-controlled chamber at 8±0.5ºC along with 90±5% relative humidity. After 5, 10, 15, 20, _____________  Author for correspondence E-mail: barman.kalyan@gmail.com