The publications in this collection do
not reflect current scientific knowledge
or recommendations. These texts
represent the historic publishing
record of the Institute for Food and
Agricultural Sciences and should be
used only to trace the historic work of
the Institute and its staff. Current IFAS
research may be found on the
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site maintained by the Florida
Cooperative Extension Service.
Copyright 2005, Board of Trustees, University
CIRCULAR 136-B "'"""""" """:: APRIL 1967 '*"^
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IN SECT CO N T .
JAMES E. BROGDON
D. O. WOLFENBARGER
Florida Agricultural Extension Service
Institute of Food and Agricultural Sciences
University of Florida, Gainesville
PAPAYA INSECT CONTROL
James E. Brogdon and D. O. Wolfenbarger'
Papayas hold much interest and some profit for many home
owners and some commercial growers in the southern part of
Florida. These plants, which have been highly publicized, have
been grown in the state for many years and produce a subtropi-
cal fruit that is
desired by many
be a limiting fac-
tor in the grow-
ing of papayas,
especially f rom
fruit set until
those likely to be
a problem are the
papaya fruit fly,
Of these pests,
the papaya fruit
fly is especially
cause it is diffi-
cult to control
and requires tak-
ing some preven-
L_.. 1_ FRUIT FLY
Fig. 1.-Papaya fruit fly laying eggs.
(Photographs by D. O. Wolfenbarger.) Papaya fruit
flies are some-
times called wasps, because of the long ovipositor of the female
fly as well as similarities in size and color. This long egg-laying
organ, which is as long as the body proper, penetrates the flesh
Agricultural Extension Service entomologist and Sub-Tropical Station
of the fruit and enters the seed-cavity (Figure 1). Eggs are
usually laid in small fruit, about 2 to 3 inches in diameter, but
they may be deposited in smaller and larger fruit, especially
during high populations of the fly.
The larvae, which are small legless maggots, feed on the seed
and interior parts of the fruit (Figure 2). When the larvae
become mature, they emerge from the fruit (Figure 3), drop
to the ground beneath the plant and pupate just beneath the
soil surface. After about 2 to 4 weeks the flies emerge to mate
and seek fruit in which to lay eggs.
It is too late to attempt control measures after the female
fruit fly has deposited eggs in the fruit. Consequently, control
procedures are directed at preventing egg-laying either by me-
chanical means or by applying sprays to kill the adult female
before she deposits her eggs.
Fig. 2-Injury caused by papaya fruit fly larvae.
Control of the fly may be achieved by mechanical protection
such as the use of paper bags. Each fruit may be enclosed by
a 3-5 pound size bag tied around the fruit stem to hold the bag.
Newspaper, one-half sheet (about 12-15 inches in size), may be
rolled to enclose the fruit, then tied around the fruit stem, and
also the free end. Bagging should begin when the fruit is small,
shortly after the flower parts have fallen. This method of con-
trol is more adapted to small (1 to 25 plants) than to large (one-
fourth acre or more) plantings. Although bagging the fruit is
the most certain method of control, it is a laborious process and
requires attention at regular intervals (10 to 14 days) to keep
the young fruit covered. Also, this procedure will injure some
of the fruit unless handled carefully. The other suggested con-
trol procedure is to apply DDT-sulfur sprays or dusts. Such
control has been effective in many plantings. A spray containing
4 pounds of 50 percent DDT wettable powder plus 8 pounds of
wettable sulfur in 100 gallons of water has been used satisfac-
torily. For small amounts, mix 4 tablespoons of 50% DDT wet-
table powder plus 4 tablespoons of wettable sulfur per gallon of
water. A 5 percent DDT dust in sulfur may be used. Six to 12
applications at 2 to 3 weeks intervals may be necessary before
favorable results are observed. During high populations of the
fly, make applications at weekly intervals. See precautions,
Fig. 3-Emergence holes of papaya fruit fly larvae.
Sanitation is important in the control of the papaya fruit
fly. It consists of destroying all dropped and prematurely ripe
fruit, as well as small fruit suspected of being infested, to pre-
vent the larvae from developing into adult fruit flies.
This insect is sometimes referred to as the fruit cluster worm,
but is commonly called papaya webworm. It develops between
and around fruits and along stems of plants under a web (Figure
4). The webworm causes injury to fruit and stem (Figure 5),
providing an entrance for the fungus disease, anthracnose.
can be controlled
by spraying with
DDT or chlordane
at the rate of 2
pounds of 50 per-
cent w etta ble
powder per 100
gallons of water
(about 2 table-
spoons per gal-
should be started
when webs are
first noticed, or
when the fruit
begins to set if
the webworm is
prevalent in the
area. (See pre-
cautions, page 7.)
Fig. 4-Webs and excrement of papaya webworms.
adult is a small white insect which often can be detected by
shaking the leaves of the plant-especially young leaves. The
young (larval) stages are flat, scale-like creatures and, except
during the first or active "crawler" stage, are fastened to the
plant and immobile. These insects have sucking mouthparts,
and most of the injury is caused by the young stages. Sooty-
mold, a black fungus, may cover leaves, fruit and stem as a result
of whitefly infestations. This fungus develops on the sweet,
syrupy excretions of whiteflies, thus detracting from the ap-
pearance of the fruit.
The papaya whitefly can be controlled with sulfur sprays or
dusts. The spray should be mixed at the rate of 8 pounds of
wettable sulfur per 100 gallons of water (4 tablespoons per
gallon) and applied when adults become numerous.
stage of large
and may grow to
three inches or
more in length.
tations occur and
large portions of
leaves may be
consumed in a
short period of
are very small,
light-g r e e n in-
sects with suck-
be controlled with
Fig. 5-Papaya webworm injury. DDT sprays as
discussed under papaya webworm, or with a 5 % DDT dust.
INSECTS AS VECTORS OF VIRUS DISEASES
Virus diseases are another limiting factor in the production
of papayas. These viruses are transmitted by aphids. Since these
insects feed on many plants and move from plant to plant, it
would be very difficult to prevent them from feeding on papayas.
It is recommended that old plants be removed within 500 feet
of a new planting.
Insecticides are poisons and should be handled with care.
Always read the manufacturer's label on the insecticede con-
tainer carefully and completely before opening. Observe all
precautions. Store insecticides in the original labeled containers
out of reach of children and pets, and away from food. Dispose
of empty containers promptly and safely.
Papayas consumed by the producer should be prepared by
the generally accepted practices of washing, peeling, etc. Pa-
payas offered for sale must conform with federal and/or state
food and drug pesticide residue regulations. Sulfur has been
declared safe and does not require any waiting period before
harvest. A waiting period of 30 days should be allowed between
the last application of DDT or chlordane and the harvest of fruit.
COOPERATIVE EXTENSION WORK IN AGRICULTURE AND HOME ECONOMICS
(Acts of May 8 and June 30, 1914)
Agricultural Extension Service, University of Florida,
and United States Department of Agriculture, Cooperating
M. 0. Watkins, Director
Four Keys to
S READ THE LABEL ON EACH PESTICIDE CONTAIN-
ER BEFORE EACH USE. Heed all
cautions and warnings.
STORE PESTICIDES IN THEIR ORIGINAL, /
LABELED CONTAINERS. Keep them out
of the reach of children and irresponsible /
people. I //
APPLY PESTICIDES ONLY AS DIRECTED.
OF EMPTY CONTAINERS