Interactions between Pratylenchus spp. and Rhizoctonia solani on resistant and susceptible potato varieties

摘要

Five potato cultivars with varying levels of resistance to black scurf were grown in Rhizoctonia solani infected soil infested with three levels of the free-living nematode Pratylenchus spp. Three varieties with moderate to good resistance to black scurf showed heightened levels of tuber symptoms in the presence of low (100 nematodes L~(-1) soil) Pratylenchus spp. and reductions in yield at the higher (500 nematodes L~(-1) soil) infestation level.Mans Piper showed no increase in the level of black scurf recorded regardless of the level of Pratylenchus spp. infestation. However a significant yield reduction was recorded in the presence of Pratylenchus spp indicating that this varieties is susceptible to attack by this free-living parasite. The susceptible cultivar Sante showed no additional yield reduction or disease symptoms as a result of the presence of Pratylenchus spp.