Contents lists available at ScienceDirect Scientia Horticulturae journal homepage: www.elsevier.com/locate/scihorti Effects of salicylic acid on postharvest fruit quality of “Kinnow” mandarin under cold storage SakeenaTul-Ain Haider a, ⁎ , Saeed Ahmad b , Ahmad Sattar Khan b , Muhammad Akbar Anjum a , Maryam Nasir b , Safina Naz a a Department of Horticulture, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, Pakistan b Institute of Horticultural Sciences, University of Agriculture Faisalabad, Pakistan ARTICLE INFO Keywords: Antioxidant activity Citrus Catalase Enzyme activity Total phenolic contents ABSTRACT The present study was conducted to investigate the effects of postharvest SA application on the fruit quality of mandarin during storage. Different concentrations of SA (4, 8 or 12 mM) were applied in the first year while, 2, 4 or 6 mM during the second year. The fruits were stored at 5 ± 1 °C and 90 ± 5% RH for 90 days and data were collected regarding different fruit quality parameters. Results revealed that maximum antioxidant activity, total phenolic contents, activities of peroxidases (POD) and superoxide dismutase (SOD) enzymes were found in the fruit treated with 4 mM SA. All SA levels had significant effects to prevent fungal attack in comparison to untreated control fruit during 90 days storage. Therefore; pre-storage application of 4 mM SA can be used safely to minimize the decay % and to maintain the highest level of bioactive compounds in ‘Kinnow’ mandarin fruit for three months under cold storage. 1. Introduction Food safety is the major concern of this era; especially it is a chal- lenging issue in developing countries like Pakistan. Mostly fresh fruits and vegetables are known due to their therapeutic values and health- promoting activities. Therefore, foods produced without the use of synthetic chemicals are getting more global attention due to the pre- sence of bioactive compounds including phenolics and their anti- oxidative characteristics (Suleria et al., 2015). These bioactive com- pounds are helpful in curing certain chronic ailments e.g. cardiovascular diseases (Sultan et al., 2014) and cancer (Parr and Bolwell, 2000). Citrus fruits are rich in phenolics, antioxidants, and other bioactive compounds but, unfortunately, antioxidants and phenolic compounds are affected by different factors including postharvest treatments and storage conditions (Connor et al., 2002; Sdiri et al., 2014). Postharvest disease incidence is the major challenge during their long term cold storage and fungi are the most important and widespread causal or- ganisms infecting a wide range of hosts including citrus fruit. Fruit rot causes major losses in fresh fruit and vegetables after harvesting, during storage and transportation. It has been reported that more than 50% of the fresh produce is destroyed every year due to fungal spoilage in developing countries (Feliziani and Romanazzi, 2013). Many fungicides such as imazalil, thiabendazole, and sodium or- thophenyl phenate are being used to overcome the postharvest fungal diseases in citrus industry (Kinay et al., 2007). However, postharvest application of fungicides is not supported by the current legislations of many developed countries, a potential market for citrus fruits. More- over, consumer’s demand for fresh fruits and vegetables (without treating synthetic chemicals) has increased during the last decade as they prefer food products which are free from fungicides residues (Feliziani and Romanazzi, 2013). Synthetic fungicides are being used for many years to control postharvest fungal problems but, in recent times, the scientists are searching for an alternative to chemical fun- gicides due to their adverse effects on human health and environment (Babalar et al., 2007). Salicylic acid (SA) is an important plant molecule, usually involved in plant defense mechanism, stress regulation and other processes re- garding plant growth and development (Asghari and Aghdam, 2010). It is also considered as a natural plant hormone that inhibits ethylene biosynthesis and delays the fruit senescence. The involvement of SA in systemic acquired resistance has also been reported (Beckers and Spoel, 2006). There are several studies indicating beneficial influences of SA treatment on storability of Banana, Peach and strawberry fruit (Srivastava and Dwivedi, 2000; Babalar et al., 2007; Khademi and Ershadi, 2013). Exogenous application of SA at low concentrations https://doi.org/10.1016/j.scienta.2019.108843 Received 9 July 2019; Received in revised form 3 September 2019; Accepted 5 September 2019 ⁎ Corresponding author. E-mail address: sakeenatulain@bzu.edu.pk (S.-A. Haider). Scientia Horticulturae 259 (2020) 108843 Available online 17 September 2019 0304-4238/ © 2019 Elsevier B.V. All rights reserved. T