Submitted to: American Phytopathological Society Annual Meeting
Publication Type: Proceedings
Publication Acceptance Date: 6/1/2006
Publication Date: 6/1/2006
Citation: Izzo, A., Mazzola, M. 2006. Differential impact of Brassica spp. seed meal amendments on fungal populations associated with roots of malus domesticus from a replant orchard site. Phytopathology. v. 96. S53.
Technical Abstract: Amending soils with Brassica spp. seed meal (BSM) is effective in reducing incidence of prominent root pathogens (e.g. Rhizoctonia solani AG5 and Pythium ultimum) in Washington state apple orchards. This effect is mediated by soil biota and varies depending upon the BSM type used and the pathogens targeted. To screen for fungi that may be impacting these processes, we examined changes to root-associated fungi from 1-yr-old apple trees grown in soils amended with two BSM treatments. Fungal communities were characterized by terminal restriction fragment length polymorphism (T-RFLP) analysis with primer sets targeting the internal impact on the fungal community was dependent upon the RSM amendment type and to some extent the group of fungi under consideration. Relative to the control, the 2 different RSM treatments created similar levels of change within each of the fungal communities however community composition was altered diferently in each case. The basidiomycete community was changed most dramatically by these treatments. Differences detected are being examined to identify new fungal taxa that contribute to the differential level of pathogen suppression observed in the field in response to different BSM treatments.