Agriculture Reference
In-Depth Information
15-20 sec, followed by spraying with 50 mM HCl, effec-
tively controlled alternaria rot in stored mango fruit. Similar
HWB treatments followed by spraying with increasing con-
centrations of Prochloraz from 45 to 900 μ g/ml in 50 mM
HCl were as effective as treatment with the acid alone in
preventing alternaria rot development. However, the reduc-
tion of disease incidence by HWB and Prochloraz treatment
(900 mg/liter) was more effective than by HWB alone after
3 weeks of storage at 12 C followed by another week at
20 C. The combination of fruit HWB and waxing yielded
high quality fruits with less decay development (Kobiler
et al., 2001).
Regnier et al. (2008) proved that modification of fruit
coatings using essential oil of Lippia scaberrima, contain-
ing (d)-limonene, R-(
dent on fruit size and shape), studies have reported HWT
to accelerate the rate of ripening (Jacobi and Wong, 1991;
McCollum et al., 1993; Jacobi et al., 1996; Jacobi and Giles,
1997) and to promote the uniformity of color development
in the mango peel of 'Tommy Atkins' fruit (Jacobi and
Giles, 1997).
SHELF LIFE EXTENSION AND QUALITY
Mangoes have a limited shelf life at ambient conditions, and
the quality of the fruit rapidly decreases once they are fully
ripe. Methods to extend fresh fruit shelf life include reduced
storage temperature, external coatings, and modified and
controlled atmospheres.
1-MCP treatment
The 1-methylcyclopropene (1-MCP or C 4 H 6 )isanethylene
action inhibitor that interacts with ethylene receptors and
thereby prevents ethylene-dependent responses in many
horticultural commodities. The 1-MCP has been formu-
lated into a powder that releases its active ingredient when
mixed with water at 40 -60 C. This nontoxic compound
can be used at very low concentrations. The beneficial ef-
fects of 1-MCP in fruit include the inhibition of respiration
and ethylene production, delayed fruit softening, restricted
skin color changes, prolonged cold storage life, and allevia-
tion of certain ethylene-induced postharvest physiological
disorders. 1-MCP treatment has also been implicated in
reducing CI symptoms.
1-Methylcyclopropene treatment of mango increased the
number of days to ripening by 5.1 days (37%) compared
with untreated fruit (Hofman et al., 2001). 1-MCP treatment
(250 ppb 1-MCP for 24 hours at 25 C) prolonged the shelf
life of mango (cv. 'Nam Dok Mai') to 15 days at 20 C with
retention of higher firmness (Penchaiya et al., 2006).
Exposure of mango (cv. 'Zihua') fruit to 100 μ l/liter
1-MCP for 12 hours resulted in the reduced softening of
produce when subsequently held in air for 7 days after
ethephon treatment and in combination with the use of
polyethylene bags the postharvest life of mango could be
extendedto30daysat20 C (Jiang and Joyce, 2000). How-
ever, Santos et al. (2004) reported that treatment of 'Rosa'
mangoes (dropped from the tree) with 1-MCP (100 ppb for
24 hour) was effective in alleviating external damage only
for earlier maturity (MG or green-yellowish) stages.
)-carvone, and 1,8-cineole as main
constituents, was effective in control of two mango posthar-
vest spoilage pathogens.
There are many reports in the literature showing
that postharvest application of chemicals such as pes-
ticides/fungicides, calcium infiltration (Mootoo, 1991),
phosphonate (Zainuri et al., 2001), salicylic acid (Zain-
uri et al., 2001; Zeng et al., 2006), gibberellic acid (Khader
et al., 1988), and 2,4-dichlorophenoxyacetic acid (Kobiler
et al., 2001) can retard ripening of mango fruit and/or con-
trol their diseases.
Thermal quarantine treatments
Thermal quarantine treatments are heat disinfection treat-
ments used as a viable nonchemical control methods for the
prevention of invasive pests, specifically fruit flies in mango
around the world. Three thermal quarantine treatments (va-
por heat treatment [VHT], forced hot-air treatment [FHAT],
and hot water immersion treatment [HWT]) are used world-
wide, but only VHT (6-hour treatment) and HWT (60-
110 min treatment) are currently accepted and in use. HWT
is the most preferred quarantine treatment because it is eas-
ily adaptable by growers and produce distributors and uses
short treatment times. It is also reliable and accurate in the
monitoring of fruit temperatures and also efficient in killing
surface decay organisms and cleanses fruit surface during
treatment.
Temperatures above 46 C have been reported to produce
excessive fruit damage (Sharp, 1994) including skin scald-
ing, abnormal erratic yellow patches of color development
with ripening, accelerated skin color development (yellow-
ing), damaged lenticels (dark halo of tissue surround lenti-
cel pores), accelerated respiration rates during the precli-
macteric period, and development of storage disease such
as anthracnose and stem-end rot (Jacobi and Wong, 1991;
Joyce et al., 1993). Under optimal HWT conditions (depen-
Surface coatings
Waxing of fruits is primarily done to improve appearance,
reduce moisture loss and respiration rate, and delay ripen-
ing, thereby extending the storage life. Mango fruits coated
with carnauba-based wax had reduced weight loss and
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