The Effect of Rhizoctonia Fragariae, Soil Type, Compost, and Mechanical Root Injury on Strawberry Growth

Abstract

Three experiments were conducted to study the influence of Rhizoctonia fragariaeanastomosis groups A and G in combination with different soil types, varying rates of compost, and following different methods of injuring the roots on strawberry vegetative growth. R. fragariaeanastomosis groups were isolated from Pennsylvania (PA) strawberry farms and obtained from the Connecticut Agricultural Experiment Station. In the first experiment, plants were inoculated and grown in two Hagerstown soils and a sandy loam soil collected from Centre County, PA. Inoculated plants generally grew better than non-inoculated plants, but the effect of inoculation depended on soil type. In another experiment, inoculated plants were grown in Hagerstown soil with 0, 10, 20, and 30 percent compost by volume. Plant growth was generally negatively related to compost concentration and inoculation with both strains tending to partially alleviate the negative effects of compost. In the third experiment, plants with roots injured by crushing or scraping had significantly higher total dry mass when plants were inoculated with CT-G and PA-A. Results from the three experiments suggest that inoculation with R. fragariaemay be beneficial to strawberry plant growth when roots are exposed to adverse conditions.