Bulletin 229, Diseases of Citrus in Florida


 On the Fruit:-The same reddish-brown, glossy, gum-soaked
blemishes that occur on the terminal twigs may also occur on
the fruit, developing at any time after the fruit is a month old
until it has attained nearly full size. Fruits affected while young
become distinctly pallid or yellowish in color in contrast with the
normal fruit, which is dark green at this stage of development.
Such fruit begins to fall at an early
age and commonly continues to do so
until there is very little left on the tree
at maturity. Soon the reddish-brown
resinous staining begins to develop.
This varies in character from numer- 4
ous, scattered, waxy eruptions ranging
in size from mere specks to spots 1/8
inch in diameter to irregular, un-
broken, dark brown blotches some.
times covering large areas of fruit
(Fig. 67). These eruptions are light
reddish-brown in color when the fruit
is young but become dark brown as it
approaches maturity. These eruptions
or stained areas usually occur most
commonly on one side or about the
stem end of the fruit but may occur
on any part of the fruit. When the
fruit is but slightly affected with only
minute eruptions the blemishes may
be confused with melanose. When the
eruptions are at all numerous the rind
becomes roughened and cracked and
frequently splits irregularly at an
early age, exposing the pulp (Fig. 68).
Fruit extensively blemished or split i ortion1 resulting fr b
commonly exhibits more or less exuda- exanthema.
tion of gum on the surface and, sometimes, an accumulation of
a clear, light-colored gum in the angles of the segments sur-
rounding the seeds. The staining of the fruit frequently occurs
on trees that show little or no evidence of exanthema otherwise.
Fruit extensively marked by this disease is worthless com-
mercially, usually being thick-skinned, insipid, and of poor keep-
ing quality.