Postharvest treatments to reduce chilling injury symptoms in stored ...

gamma rays, electrons, X-rays and microwaves. Spalding and von Windeguth (1988)
reported that the percentage of decayed mango is minimized when they are exposed to
750 Gy or higher, but fruit peel shows scald-like symptoms with irradiation doses over
500 Gy.
Radiation also affected ripening, because of the specific biochemical processes.
According to Spalding and Reeder (1986), combination of irradiation and HW (53 °C), or
0.2 % hot imazalil (53 °C) was more effective for storage purposes. Gamma irradiation
(30 Krad) caused ripening delay of seven days in comparison to mango stored at room
temperature.
2.2.6 Storage by using chemicals
Treatment efficiency varies with infection level and storage regime. The length of
shelf life depends on cultivar, injury, maturity at harvest, calcium spray, and exposure to
ethylene (Anonymous, 1988, Coates et al, 1995). A dip in 4-6 % calcium chloride can
increase the shelf life of some cultivars (Singh et al., 1993). Ethylene is used to reduce
time for ripening initiation and it can also enhance skin color of the fruit (S. P. Burg and
Burg, 1962). In South Africa, a benomyl dip for 5 min at 55 °C is recommended just after
picking of fruits, which can control soft brown rot (Sepiah, 1986). Prochloraz also
provides good protection from anthracnose and Alternaria rot in mango (Johnson and
Coates, 1993). Prior to harvest Gibberellic acid (GA3) spray can retard mango ripening
at ambient temperature for up to six days of storage (Khader, 1991). Calcium chloride
treatment resulted in low ethylene production, low respiration, and helped to reduce the
occurrence of storage decay (Eeden, 1992).
2.3 Postharvest Heat Disinfestation Treatments
For fresh mangoes postharvest heat disinfestation treatments have been well
known over the past decades. Although heat has fungicidal and insecticidal action it often
has detrimental effect on the crop. The fruit is heated for a defined period of time to
ensure the energy gets transferred from the heating medium to the fruit. The heating
medium used may be air or water. In 1989, Couey reported that heat-treatments are used
to control postharvest diseases and insect pest. This method is cheap and environmentally
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