Plant-Parasitic Nematodes in Managed Turfgrass Systems.

Plant-parasitic nematodes (PPN) can be detrimental to the playability of golf course putting greens as the root damage they cause reduces the plant’s ability to take up nutrients and water. The weakened plants have increased susceptibility to drought, nutrient deficiency, attack by pathogens, and invasion by weeds. Research into this pest in Canada is limited as PPN are not usually considered a major pest of turfgrass in colder climates. Determining how populations of PPN differ between regions and how they change over time, both during the course of a season and as greens age, is important to managing their populations. A survey was conducted to determine population dynamics on golf course greens throughout southwestern Ontario and other parts of Canada. Nematode populations along with soil chemical and physical properties were measured on golf course greens in Ontario and the provinces of British Columbia, Alberta, Quebec, New Brunswick, and Nova Scotia. These factors as well as age of the green were subjected to ANOVA and regression analysis to determine the presence of correlations between the variables. There was a statistically significant difference between greens over the age of 20 years and those under the age of 20 years in the summer and fall of 2013 (p = <0.0001), with older greens having more PPN. Regional variation within Ontario was not significant; however, the variation between provinces was significant in the spring of 2014 (p = <0.0001). Soil textural properties were correlated with nematode populations more frequently than soil nutrient properties. The fine fractions of the soil were often positively correlated with some or all of the nematode genera present in the spring, summer, and fall. These finding are an important step towards understanding PPN populations on golf greens in Canada.