The Battle Heats Up Between Mangoes, Fruit Flies By Ann Perry
June 10 , 2008
Farmers around the world produced approximately 60 billion pounds of
mangoes (Mangifera indica) in 2004, according to the latest available
figures. That's a bounty for fruit lovers and fruit flies (Anastrepha spp.)
alike. Now Agricultural Research Service (ARS) entomologist
A. Jenkins has found a low-tech solution for reducing fruit fly
infestations in mangoes.
Jenkins works at the ARS
Agricultural Research Station in Mayaguez, Puerto Rico. Naturalized and
ornamental mango trees are widespread in Puerto Rico, and ripe mangoes often
fall from these trees and remain uncollected for several days. This provides
fruit flies with ample breeding opportunities.
In his study, Jenkins and his team collected ripe mangoes that had
fallen to the ground. One group of mangoes was shaded--either by a tree or a
cloth--and left outside. A second group was stored indoors. A third group was
left exposed to full sunlight, and a fourth group was covered with a black
plastic garbage bag and then left in full sunlight.
The researchers recorded ambient temperatures and the internal fruit
temperatures of all the mangoes several times daily. On clear days, the two
sun-kissed groups of mangoes had internal temperatures peaks ranging from
126° F to 138° F. Even on cloudy days, their core temperatures peaked
at 122° F. These were well above the 77° F peaks in the indoor mangoes
and the 99° F peaks in the shaded mangoes.
After three days, the outdoor mango groups were moved inside and
monitored for the emergence of larvae and pupae. Jenkins observed that mangoes
stored indoors almost always produced many more larvae than the groups of
mangoes that had been basking in the sun.
In areas where mango is not being grown commercially, ripe mangoes
that have fallen from the tree remain shaded on the ground until they are
gathered up and removed. When fruit flies use these mangos for breeding, the
shade keeps the fruit’s core temperatures from reaching peaks lethal to
Removing the fruit from the shade of backyard trees, along with other
strategies, may help reduce fruit fly breeding opportunities and support
existing strategies to control fruit flies in commercial produce.
ARS is a scientific research agency of the
U.S. Department of Agriculture.