Apple, Test of Acaricides and Insecticides, 1973, 1974

This experiment was carried out in an enclosed insectary at the Penn State Fruit Research Laboratory in Biglerville, Pennsylvania. It was designed to study the toxicity to adults of S.punctum of 22 registered and experimental insecticides and acaricides. The ladybird beetle, S.punctum, is one of the most important native predators of the European red mite in Pennsylvania fruit orchards. Adult beetles for the experiment were collected from the same orchard in 1973 and 1974. Collection dates were July 10, 12, and 25 in 1973 and July 3, 9, 23 and August 21, 1974. The beetles were collected from the trees by placing a one-yard square cloth tray beneath a limb and tapping it to dislodge the beetles. They were then taken from the tray with an aspirator and transferred to styrofoam cups for transport to the insectary. The capture cups as well as the test cups were eight ounce number 320 styrofoam cups. Two holes were cut in opposite sides of me cups, then these and the top were covered with Dacron Ninon screening. Three leaves infested with European red mites were placed in each test cup. The materials to be tested were then weighed and the solutions were mixed in the appropriate amounts with water. A small amount of each test material was then placed in separate 50-ml beakers. The beetles were then taken from the capture cups and placed in the test solutions, immersed, and allowed to remain in the solution for 15 sec. The beetles were then removed from the solution with a probe while still wet and placed on the leaves in the test cups. Lots of ten beetles each were placed in individual cups with twenty beetles total tested in each material. Survival was recorded after one, twenty-four, and forty-eight hours. Four control cages were maintained for each test day; twenty beetles for a dry check and twenty for a wet (water) check. Relative humidity ranged from 34 to 100%; the temperature range was from 53 to 90° F.