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TATE PLANT BOARD 
May 1953 E-856 
United States Department of Agriculture 
Agricultural Research Administration 
Bureau of Entomology and Plant Quarantine 
TESTS OF INSECTICIDES FOR CONTROL OF THE PICKLEWORM 
AND ASSOCIATED INSECTS ON CUCUMBERS AND SQUASH- -1948-51 
By W. J. Reid, Jr., and F. P. Cuthbert, Jr. . 
Division of Truck Crop and Garden Insect Investigations^-' 
The pickleworm ( Diaphania nitidalis (Stoll)) is a serious pest of 
cucurbit crops in the South Atlantic and Gulf States. It frequently causes 
considerable damage in adjoining States, and occasionally occurs as far 
west as Texas, Kansas, Missouri, and Iowa, and as far north as the 
tier of States extending from Illinois eastward to Connecticut, including 
New York. Summer squash is its favorite host, but it often severely 
damages cucumber and muskmelon. Occasionally young tender fruit of 
winter squash is attacked. The pickleworm is active throughout the 
winter in the extreme southern part of Florida, where its cultivated or 
native hosts are available continuously. From this and similar sub- 
tropical areas the insect gradually spreads northward each year, and 
usually appears later in the spring than most insects. Evidently it 
does not survive the winter as far north as the Carolinas. 
The melonworm ( Diaphania hyalinata (L.)), a species related to but 
less destructive and more easily controlled than the pickleworm, has 
about the same distribution in the United States. In addition, it has been 
reported from Arizona, New Mexico, and southern California, and 
adults have been taken in Canada. Apparently it also overwinters only 
in semitropical regions. 
The banded cucumber beetle ( Diabrotica balteata Lee.) and the 
spotted cucumber beetle ( Diabrotica undecimpunctata howardi Barber) 
often injure young cucumber plants, and the striped cucumber beetle 
( Acalymma vittata (F.)) damages the plants and fruits. The melon aphid 
( Aphis gossypii Glov.) often causes serious damage to cucumbers. 
Because of its habit of tunneling into the stalks, vines, buds, 
flowers, and fruit of cucurbits, the pickleworm has been difficult to 
control with the insecticides known prior to World War II. Studies con- 
ducted near Charleston, S. C, from 1930 through 1934 showed the need 
for more effective control measures. In 1948 these studies were re- 
sumed to determine the control value of some of the newly developed 
1/ In cooperation with the South Carolixia Agricultural ExDeriment 
Station. 
