Weight Loss Of Mango Fruit

4. Discussion The percentage of weight loss is one of the essential aspects to determine postharvest fruit loss. Our study showed that the percentage of weight loss of mango fruits increased progressively during storage period. However, 2 mmol/l PUT significantly decreased the percentage of weight loss (Table 1). It could be suggested that PUT inhibited respiration rate, and ethylene production thus delaying postharvest weight loss (Valero, Martínez-Romero, Serrano, & Riquelme, 1988). Our results are in agreement with the finding of Davarynejad et al. (2013) that postharvest application of PUT significantly reduced the percentage of weight loss in apricot fruit. In addition, Jawandha, Gill, Singh, Gill, & Singh (2012) showed that PUT treated

Fruit softening during the ripening process were due to the changes of cell wall degrading enzymes such as polygalacturonase (PG), pectin methyeaterase (PME), pectin esterase, and cellulase (Mithcham, Gross & Ng, 1991). The results in this experiment revealed that, mango fruit treated with 2 mmol/l PUT showed an increased fruit firmness during storage time. It has been reported that application of polyamines enhances fruit firmness in different fruits, including plums (Davarynejad, Zarei, Nasrabadi, & Ardakani, 2015), apricot (Martinez-Romero et al., 2002), pomegranates (Barman, Asrey, & Pal, 2011), and grape (Harindra Champa, Gill, Mahajan & Bedi, 2015). The influence of polyamines on fruit firmness augmentation can be attributed to their capacity in cross-linking to the carboxyl group of the pectin substances in the cell wall, resulting in rigidification (Abbott, Conway, & Sams, 1989). This binding between polyamines and pectin also inhibited cell wall-degrading enzymes, such as pectin esterase, polygalacturonase (PG), and pectin methyeaterase (PME), which reduced fruit softening after harvest (Valero, Martínez-Romero, & Serrano,

During storage period, the concentration of TSS continuously increased because of the hydrolysis of polysaccharides. During respiration, TA related to the concentration of organic acid, and the reduction of TA content was due to consumption of organic acids in fruit (Khosroshahi, Esna-Ashari, & Ershadi, 2007). The concentration of TSS was significantly affected by the application of polyamines. Our present experiment revealed that 2 mmol/l PUT treated fruit exhibits the lowest TSS, and the highest TA content during storage period. This effect of PUT can be attributed to the reduction of respiration rate, ethylene production, and a delay in ripening process. Similar results have also been reported in pomegranate (Mirdehahan et al., 2007) and apricot (Martinez-Romero et al.,