Plant-Parasitic Nematode Population Dynamics and Alternative Management Options for Tomatoes in Southwestern Ontario

Plant-parasitic nematodes (PPN) can be damaging pests on tomatoes (Solanum lycopersicum) but their population dynamics in southwestern Ontario are unknown. Additionally, growers are unable to obtain accurate population estimates, and relate estimates to published threshold levels, due to inconsistencies in laboratory extraction methods. Finally, few management options are available to reduce PPN damage. The objectives of this study were to examine the population dynamics of PPN in southwestern Ontario tomato fields, compare nematode extraction methods from soil, identify tolerant tomato cultivars, and begin to establish threshold levels. Pratylenchus spp. nematodes were the most common genus found in the survey, present in 100% of fields sampled. Modified and optimized sugar centrifugal flotation methods extracted all PPN genera equally as well or better than the Baermann pan method. The cultivar tolerance trials showed differences in cultivar root galling induced by Meloidogyne hapla; however, high variance prevented further conclusions from being made.