EVALUATION OF SYSTEMIC PESTICIDES FOR USE AGAINST HOP APHIDS AND TWOSPOTTED SPIDER MITES, AND INTERACTIONS BETWEEN CARBON-14 - LABELED ALDICARB, HOPS, AND HOP PESTS (UPTAKE, TRANSLOCATION).

摘要

Five granular, systemic pesticides were evaluated for control of hop aphids and twospotted spider mites. Three organophosphates (disulfoton, phorate, and terbufos) and 2 carbamates (aldicarb and oxamyl) were tested. Aldicarb provided the most effective aphid control, and remained effective at 2 lb active ingredient per acre (a.i./a.). Mite control was poor at this low rate, however, oxamyl was an excellent acaricide. Disulfoton, phorate, and terbufos were ineffective at low rates.;Aldicarb uptake and movement in potted hops were studied with a C14 label. Uptake began within 6 hr of application and continued for 18 to 48 hr, depending on the application rate; higher rates took longer. Aldicarb accumulated in the greatest proportions in leaves after 84 hr. Leaf position on the plant was unimportant. Very little accumulated in stems or roots.;The ppm of aldicarb and it primary metabolites in fresh and dried leaves and cones of potted hops, treated with the equivalent of an 8 lb a.i./a., were determined 60 days after application. Aldicarb residues in fresh leaves ranged from 2.2 - 36.5 ppm, with the highest residues present within 10 days after application. Sulfoxide residues reached their peak of 89.9 ppm at 25 days after application, and then declined to 16.5 at 60 days. The sulfone remained low throughout the experiment, reaching its peak of 14.9 ppm at 45 days.;Aldicarb residues in fresh cones remained low, with the peak level of 1.3 ppm occurring 60 days after application. The sulfoxide level remained low (3-4 ppm) for the first 35 days, then increased to 11.6 ppm at 60 days. The sulfone remained low, reaching its peak of 3.1 ppm at 60 days.;Application to aldicarb with 3 shanks was more effective in controlling mites than with 2 shanks. There were no significant differences among modes of oxamyl application for aphid control, and no application differed significantly from the untreated mite population.