Pear, Pear Psylla, Screening of Insect Growth Regulators, 1986

Tests were conducted on pear seedlings (small nursery liners) growing in 4-inch pots and on terminal shoots of ‘Bartlett’ in a Research Center orchard. Seedlings were infested with PP eggs by caging 20 adults on each for 5 days. Shoots in the orchard were naturally infested with mixed stage populations. Treatments were applied to seedlings 1 day before adults were caged on them by dipping them for 5 s in water dilutions of candidate pesticides. Shoot tests were replicated 3 times and were sprayed to the point of drip with a hand pump sprayer. Treated seedlings were held post-treatment in a growth room at ca. 75°F and 16 h photoperiod for 4 weeks. Treated shoots remained in the orchard post-treatment. Treatments were evaluated by counting eggs and nymphs on the entire sample using a dissecting microscope.