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AbstractIn laboratory and field studies with the codling moth, Cydia pomonella(L.), TH 6043 and TH 6044, experimental benzoylphenyl urea chitin-synthesis inhibitors, were as effective as diflubenzuron in reducing egg hatch and subsequent larval entry when eggs were deposited on previously treated fruits or foliage. All three compounds exhibited extended residual activity, with significant reductions in egg hatch occurring over a 19-week period. TH 6045 exhibited little activity against codling moth. All compounds tested were relatively ineffective in reducing egg hatch or subsequent larval entry when they were applied topically to deposited eggs, except for the red ring stage of development which was slightly affected.

AbstractIn laboratory studies with the codling moth, Cydia pomonella(L.), TH 6043 and TH 6044, new benzoylphenylurea chitin-synthesis inhibitors, were more effective than TH 6045 and diflubenzuron in reducing hatch of eggs from treated adults. With TH 6043 and TH 6044, egg hatch was reduced only when the female of each mating pair was treated. Topical application of diflubenzuron to adults moderately reduced egg hatch while TH 6045 had no effect. Diflubenzuron also reduced oviposition by females. None of these compounds adversely affected mortality, longevity, or mating propensity of adults.

The peach-twig borer, Anarsia lineatella(Zeller), is one of the most important pests of peaches, almonds, and other stone fruits in the western United States (Bailey 1948), with larvae infesting both twigs and fruit. Infested fruit cannot be marketed and twig injury is damaging to young trees because the young worms burrow into the tender terminal growth of the twigs and cause the rapidly growing twigs to wilt. In this way, infestations by the peach-twig borer interfere with development in young orchards (Newcomer 1966).

Cyclohexyl phenylacetate, a lure for male and female checkered flower beetles, Trichodes ornatus Say, impregnated on rubber septa was effective for 6 weeks in the field. Beetle captures in traps baited with septa containing 200–400 mg of the lure were statistically equal. Septum containing 400 mg lure initially will lose ca. 200 mg through evaporation by the 43rd day; thus, two baits suffice for the beetle’s principle flight period which lasts from early June to mid-August in Washington.

To determine the trends in populations of the green peach aphid, Myzus persicae (Sulzer), and the aphid forms present on peach trees in September and October before leaf fall, the arrival of 2 winged forms of the aphid and the buildup of the wingless female populations were investigated in the Yakima Valley, Washington, in 1965. In addition, the role that predaceous insects play in suppressing the aphid populations was observed. Results indicated that after the winged gynoparae arrived on the peach trees, the oviparous population rapidly increased and that male arrival was synchronized with maturing of oviparae. Syrphids were the only predators that effectively suppressed the aphids. Evidence of feeding activity by syrphid larvae was found on more than half the aphid-infested leaves. Maximum stimulus for egg deposition by syrphids was about 30–40 aphids per leaf.