Preplant Soil Treatments Influence Tree Performance and Nematode Dynamics in Replanted Cherry Orchards

In this 2-year field study, the impacts of preplant soil management strategies, including soil fumigation, nematicide application, and organic amendments, on the growth and nematode community dynamics on cherry cultivars 'Emperor Francis' and 'Ulster' grafted to 'Mahaleb' rootstock were investigated in a replanted orchard site. In the first year, fumigation with 1,3-dichloropropene-chloropicrin mixture (Telone C-35) led to significantly increased trunk cross-sectional area and canopy height in both cultivars. <i>Pratylenchus penetrans</i> population densities were suppressed only short term. Plots treated with the fungicide/nematicide fluopyram (Velum Prime) had <i>P. penetrans</i> reproduction factors below one throughout both years independent of the scion. Additionally, the combined application of Seed Starter 101, Dairy Doo compost, and straw mulch reduced the reproduction factor of <i>P. penetrans</i> to below one in the first year. In the same time period, this combinatory treatment had the highest reproduction factor for bacterivore and fungivore nematodes. Based on the results of this study, fumigation with Telone C-35 resulted in improvement of tree establishment and provided effective short-term suppression of <i>P. penetrans</i>. Velum Prime exhibited longer-term efficacy for the suppression of <i>P. penetrans</i>.