Influence of harvest location and cultivar on pericarp browning and biochemical fruit quality of litchi (Litchi chinensis Sonn.).

Litchi (Litchi chinensis Sonn.) belongs to tropical/ subtropical areas that are considered to be originated near Southern China and Northern Vietnam with china being the largest producer in the world (Menzel, 2001). It has high market value due to deliciously flavoured translucent juicy aril. It is one of the most nutritious fruit as it contains 16.83 g carbohydrate, 72 mg vitamin C, 830 mg protein, 171 mg potassium and 10 mg magnesium per 100 g of fruit (Anonymous, 2012). In Pakistan, litchi is grown on an area of about 572 ha with 9250 tons production (Shah, 2003). However, postharvest pericarp browning is the main issue in litchi fruit which involves rapid browning of fruit skin after harvest (Kumar et al., 2013), thus affecting the fruit quality and hindering its market potential (Rajwana et al., 2010). Different biochemical/physiological changes, enzymatic changes such as, reduction of membrane integrity, degradation of anthocyanins, increase in peroxidase (POD), polyphenol oxidase (PPO) activities and catalyzation of superoxidation reaction have been reported to be associated with pericarp browning in litchi (Jiang, 2000). Several efforts have been made to overcome this issue by using postharvest fruit coatings (Joas et al., 2005), different antioxidants (Kumar et al., 2013), oxalic acid (Zheng and Tian, 2006), ascorbic acid (Sun et al., 2010), however, with variable and sporadic results. Due to its unique taste and high nutritional value, the demand of litchi is increasing day by day in Pakistan. At present no information is available about the effect of harvest locations and cultivars on the pericarp browning and fruit quality of litchi. Previously, location influenced many fruit characteristics that vary with cultivars (Knee and Smith, 1989). It is hypothesized that incidence of pericarp browning and quality will be affected by locations of land and cultivars. Therefore, it is the need of the time to further investigate that which area and cultivar is best suited for litchi cultivation with reduced pericarp browning at ambient conditions. Hence, present study was conducted to determine the effect of locations and cultivars on pericarp browning, enzymatic activity and fruit quality of litchi at ambient conditions.