Effects of seed row and foliar applied pesticides on the yield of lucerne in clay soil, in the presence or absence of lucerne stem nematode, Ditylenchus dipsaci

Abstract

SummaryCarbofuran at 1·5 kg a.i./ha applied around the seeds during sowing in spring controlled lucerne stem nematode and Sitona damage to lucerne and increased herbage yields in the susceptible cv. Europe. Such treatment was also beneficial to Europe in soil not infested with lucerne stem nematode and to the ‘resistant’ cv. Euver sown in infested soil. Subsequent treatment of the soil in spring each year with thiabendazole did not enhance lucerne yield but aldicarb at 1·5 kg a.i./ha watered onto the stubble and hydraulic or electrostatic sprays of carbendazim, thiabendazole hypophosphite, thiodicarb, dimethoate or pirimiphos methyl applied to new foliage after each herbage harvest lessened stem nematode injury and increased herbage yields in one experiment but had less or no effect in another.