Managing Plant–Parasitic Nematodes in Established Red Raspberry Fields

Abstract

The efficacy and phytotoxicity of postplant treatments to control root lesion nematodes [RLN (Pratylenchus penetrans)] and dagger nematodes [DN (Xiphinema bakeri)] in red raspberry (Rubus idaeus) were evaluated in four field studies, each conducted over 1 to 3 years. Spring spray applications of oxamyl or fosthiazate reduced RLN and DN population densities for up to 2 years, but fall oxamyl sprays and spring drip-applied oxamyl applications were not effective. Oxamyl application rate determined the duration of nematode suppression. Two spring applications of oxamyl at 2 lb/acre provided more than 2 years of suppression, while two spring applications of 0.8 lb/acre suppressed nematodes for only 1 year. Spring oxamyl applications reduced ‘Nootka’ fruit yield for one season, but did not affect ‘Willamette’ yield. Fall spray-applied fenamiphos, fall and spring spray-applied DiTera (a fermentation product of the fungus Myrothecium verrucaria), fall drip-applied 1,3-dichloropropene, and spring shallow-incorporated abyssinian mustard (Brassica carinata) seed meal suppressed RLN briefly (less than 6 months) or not at all.