title: Effect of Application Timing of Oxamyl in Nonbearing Raspberry forPratylenchus penetransManagement.
abstract: In 2012, the Washington raspberry (Rubus idaeus) industry received a special local needs (SLN) 24(c) label to apply Vydate L®(active ingredient oxamyl) to nonbearing raspberry for the management ofPratylenchus penetrans. This is a new use pattern of this nematicide for raspberry growers; therefore, research was conducted to identify the optimum spring application timing of oxamyl for the suppression ofP. penetrans. Three on-farm trials in each of 2012 and 2013 were established in Washington in newly planted raspberry trials on a range of varieties. Oxamyl was applied twice in April (2013 only), May, and June, and these treatments were compared to each other as well as a nontreated control. Population densities ofP. penetranswere determined in the fall and spring postoxamyl applications for at least 1.5 years. Plant vigor was also evaluated in the trials. Combined results from 2012 and 2013 trials indicated that application timing in the spring was not critical. Oxamyl application reduced rootP. penetranspopulation densities in all six trials. Reductions inP. penetranspopulation densities in roots of oxamyl-treated plants, regardless of application timing, ranged from 62% to 99% of densities in nontreated controls. Phytotoxicity to newly planted raspberry was never observed in any of the trials. A nonbearing application of oxamyl is an important addition to current control methods used to manageP. penetransin raspberry in Washington.
authors.affiliation: U.S. Department of Agriculture-Agricultural Research Service Horticultural Crops Research Laboratory, 3420 NW Orchard Avenue, Corvallis, OR 97330.
authors.forename: Inga A
authors.initials: IA
authors.lastname: Zasada
authors.affiliation: Walters Ag Research, 2117 Meadows Lane, Anacortes, WA 98221.
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Walters
keywords: Praytlenchus penetrans; Rubus idaeus; postplant nematicide; root lesion nematode; vydate