Pomegranate - Tropical and Subtropical Fruits: Postharvest Physiology, Processing and Packaging - page 517

deficiencies, large variation in day and night temperatures,
dry breeze, and some diseases and pests are the likely causes
of the splitting and cracking (Yilmaz, 2007; Holland et al.,
2009). The extent of the splitting and cracking may be
reduced or prevented by using split/crack-resistant types
such as 'Izmir-16' and 'Beynar' in Turkey (Yilmaz, 2007;
Holland et al., 2009).

Scald
Scald, a physiological disorder limiting long-term of stor-
age, develops with time, appears first on the stem end, and
expands up to 60% of the skin but does not affect the internal
tissue. Scald incidence and severity may be related to senes-
cence since pomegranates harvested late showed higher
scald degree than those harvested early. Among postharvest
applications or treatments tested (such as diphenylamine,
1-MCP or CA), only the controlled atmosphere (5% O 2 +
15% CO 2 ) seems to be successful to control this disorder
(Defilippi et al., 2006).

Harvest blemish
For fresh consumption or processing, fruit should be hand-
picked and handled very delicately. Even a small bruise or
scratch may cause a dark blemish on the rind, resulting in
a sharp decline in commercial value.

Internal breakdown
Internal breakdown is another physiological disorder in
pomegranates, although the cause has not been explained
yet. The symptoms of the disorder include underdeveloped
light red-colored arils (Ryall and Pentzer, 1982).

Weight loss
Weight loss or water loss is the main problem for
pomegranate fruit during postharvest life. Among the
postharvest treatments tested, chilling temperature regime
( 5 ◦ C) at high relative humidity (RH) (90-95%), modified

atmosphere packing, film wrapping, waxing and controlled
atmosphere (CA) storage have been found effective in lim-
iting weight loss.

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Postharvest pathology
Gray mold ( Botrytis cinerea ) rot, green mold ( Penicillium
digitatum )rot, Cladosporium spp., Aspergillus spp., and
Alternaria spp. are the most common postharvest diseases
of pomegranate fruit (Roy and Waskar, 1997; Pekmezci and
Erkan, 2010). Other fungi or bacteria causing pomegranate
fruit decay or damage include Cercospora spp., Penicillium
spp., Colletotrichum gloeosporioides , Sphaceloma puni-
cae , Coniella granati Sacc. Petr. & Syd., Phytophthora
spp., Glomerella cingulata , Rhizopus spp., Nematospora
spp., and Pestalotiopsis versicolor (Holland et al., 2009;
Palou and del Rio, 2009). Penicillium digitatum and
Botrytis cinerea are likely the most frequent pathogens of
pomegranate fruit and the most damaging (Palou and del
Rio, 2009). In most cases, calyx is the entry point of gray
mold, resulting in light brown, tough, and leathery skin as it
progresses (Salunkhe and Desai, 1984). Heart rot is another
disease caused by Aspergillus spp. and Alternaria spp.
(Salunkhe and Desai, 1984). The disease progresses while
on the tree; symptoms of the diseases are slightly abnormal
skin color and blackened arils (Salunkhe and Desai,
1984). A noninvasive crown mold could develop on the
stamen remains, leading to loss of aril color and off-flavor
development and to ethanol buildup (Nerya et al., 2006).
Fludioxonil R

Chilling injury
Storage at 5 ◦ Corbelow5 ◦ C for even 1 month may ini-
tiate chilling injuries in pomegranates, and the degree of
the chilling injury symptoms increases with time and tem-
perature decrease under 5 ◦ C (Elyatem and Kader, 1984).
'Wonderful' cultivar can be safely stored at 5 ◦ C for up to 2
months; however, the minimum safe temperature for longer
storage is 7.2 ◦ C (Crisosto et al., 2010). Chilling injuries are
easily perceivable after transferring fruit to 20 ◦ C, causing
browning of the rind, surface pitting, husk scald, pale color
of the arils, brown discoloration on the white segment, in-
crease in electrolyte leakage, and increase susceptibility to
decay organisms (Elyatem and Kader, 1984; Artes et al.,
2000; Mirdehghan et al., 2007b).
To alleviate chilling injury symptoms, some postharvest
treatments have been examined, and the following appli-
cations have been found successful to a variable degree:
controlled and modified atmosphere storage (Nerya et al.,
2006), thermal application by air or hot water dip (Artes
et al., 1998, 2000; Mirdehghan et al., 2007a, 2007b), in-
termittent film wrapping and coatings (Nanda et al., 2001;
D'Aquino et al., 2010), and polyamine application (Mird-
ehghan et al., 2007a) and salicylic acid treatment (Sayyari
et al., 2009). Of these postharvest treatments, the polyamine
application seems to be best tool to retard chilling injury
symptoms when the fruit is stored at chilling temperatures
(Mirdehghan et al., 2007a).

, a synthetic analogue of pyrrolnitrin
(Rosslenbroich and Stuebler, 2000) and a member of the
class of phenylpyrroles, has been recently registered for
controlling postharvest decay of pomegranates and other
horticultural crops in the United States (Tedford et al.,
2005). Fludioxonil alone or in combination with film wrap-
ping has been shown to quite effectively control mold