BUREAU OF ENTOMOLOGY AND PLANT QUARANTINE 37 
the biological control of the fly will ever eliminate the need for careful 
quarantine safeguards, treatments of fresh fruits and vegetables for 
export, or the use of insecticides to protect certain of the more sus- 
ceptible hosts, such as mango and avocado. 
Tropics searched for oriental fruit fly parasites 
The search for natural enemies of the oriental fruit fly, in progress 
since 1948, continued. Shipments of field-collected fruit fly puparia 
from India, Siam, the Philippine Islands, Borneo, and Africa totaled 
about 1,725,000 puparia. From these, about 60,000 parasites, repre- 
senting 31 species, were reared. 
This work was partly financed by funds authorized under the Re- 
search and Marketing Act. 
New commodity treatments ease pinch on fruit exports from Hawaii 
Studies on the preexport treatment of fruits and vegetables sus- 
ceptible to infestation by the oriental fruit fly resulted in the adop- 
tion of a fumigation method that has greatly simplified the whole 
problem of commodity treatments. It was found that ethylene di- 
bromide is extremely toxic to fruit fly eggs at very low dosages. As 
little as one-half pound of this fumigant to 1,000 cubic feet with a 
2-hour exposure insures complete destruction of all fruit fly stages. 
Extensive tolerance tests showed that Hawaii-grown avocado, bell 
pepper, bitter melon, Cavendish bananas, cucumber, papaya, pine- 
apple, string beans, and zucchini squash will stand such treatment 
without injury. The vapor-heat treatment was also successfully ap- 
plied to pineapples that had been conditioned prior to heating. 
The new fumigation method will have a stimulating effect on the 
development of small-grower agriculture in the Hawaiian Islands, 
now that most important commodities may be grown with the as- 
surance that they can be qualified for export. California cooperators 
have also determined that this type of fumigation would be suitable 
for many of their fresh fruits and vegetables. 
Several chemical controls effective against oriental fruit fly 
The results of a large-scale test with a methyl eugenol-parathion 
lure that attracts and kills' male flies suggest that this method may 
provide substantial and cheap control of the fruit fly when applied 
on an area-wide basis. However, the lure needs further experimental 
evaluation in field tests to determine its ultimate worth. A newly 
developed olfactometer that is convenient, reliable, and effective 
greatly speeded the screening of possible attractants and repellents. 
Active ingredients in moderately large quantities in formulations 
containing lindane, parathion, dieldrin, and aldrin have effectively 
killed flies during their pupal stage in the soil. These insecticides 
offer a wide choice of materials for a localized eradication program. 
They, as well as EPN, Dilan, and DDT, at concentrations commonly 
used in orchard spraying, were found to be effective both as residual 
and contact poisons. How much protection they will give when ap- 
plied to fruits growing in commercial plantings and home gardens 
will be determined by further study. 
Parathion, dieldrin, and aldrin have also functioned as fumigants 
in controlling the fly. Parathion, furthermore, may be highly effec- 
