Lemon and Lime - Tropical and Subtropical Fruits: Postharvest Physiology, Processing and Packaging - page 373

mold (Figs. 20.4c and 20.4d) can enter through damaged
areas in the fruit rind made during harvesting and handling
and appear in storage.
Sour rot (Fig. 20.4e) can occur in mature lemon fruit
damaged during harvesting as well as when fruits have
been treated with a fungicide that controls green or blue
mold but not sour rot. It is very attractive to vinegar flies.
The brown fungus ( Phytophthora spp.) is present in the
soil, and the spores are carried onto the fruit in rain splash
(Fig. 20.4f). The infection can spread upward throughout
the tree in the water during wet conditions.
'Key' lime is very susceptible to stem rot (Table 20.6).
Stem rots caused by D. natalensis and Alternaria citri are
important postharvest diseases of 'Persian' lime.

rupturing of oil glands. Peteca is a postharvest disorder of
lemons, the cause of which is not known. The fruits develop
either large sunken areas in the rind or pitting of the sur-
face soon after packing. Oleocellosis can develop on lime
peel if harvested early in the morning or immediately after
rainfall when the peel is turgid. Stylar-end breakdown is a
significant problem with limes, which begins as an apparent
breakdown of tissues at the stylar end of the fruit, making it
to take a wet appearance. High field heat and rough handling
can aggravate the incidence (Malo and Campbell, 1994).

Current storage and shipping practices
Lemons are cool-stored after harvest for a long period of
time; short- and long-term storage can be used to market
fruit at times of peak market demand, a common method
in California. However, the storage time depends on the
stage that the fruit is picked. Fruits harvested when silver-
green are stored for around 6 weeks, light green fruit for
2 months, and dark green fruit for 5-6 months (Hardy,
2004). If the fruits are internally mature when harvested,
the quality characteristics such as peel thickness and juice
content can be improved during storage. The optimum tem-
perature and relative humidity range for lemon storage is

Physiological disorders
Physiological disorders of lemon and lime fruits are out-
lined in Table 20.7. Oleocellosis also known as oil spotting
is caused by the phytotoxic action of peel oil released onto
the rind as a result of abrasion, rough handling, thorn punc-
tures, or other injuries. The rind of lemons is especially
prone to oleocellosis. Foggy wet conditions worsen the
disorder, making the rind more turgid and subject to the

Table 20.7. Physiological disorders of lemon and lime

Disease Cause Symptoms Occurrence Control

Oleocellosis A burnlike damage

from the oil released
from oil glands
when the rind tissue
is damaged.

Superficial damage results in
light yellow colored patches.
Severe damage results in
dark brown patches and rind
collapse.

Lemon and
lime

Pick only dry fruit and do
not harvest fruit in
cold, wet conditions or
green fruit in early
morning. Careful
handling of fruit
during and after
harvest to reduce
damage to the rind.

Peteca Unknown Large sunken areas in the rind

or pitting of the surface soon
after packing. Severity
increased by spraying fruit
with high concentration oil
sprays, imbalance of calcium
and potassium in the peel
and cold conditions prior to
harvest.

Lemon Susceptible fruit should

not be subject to
excessive brushing and
waxing. Avoid storage
of fruit below 13 ◦ C.

Storage below 13 ◦ Cand
improving ventilation
in storage.

Membrane
stain

Membrane between segments,
or capillary walls, shows
irregular brown or black
areas.