During the 2003-processing season 15 seedlots from 5 different conifer species were selected to determine the presence of Fusarium spp. on cones, debris and seed at various stages during cone and seed processing. Seed from the various stages were fungal assayed with and without surface sterilization to determine the importance of internal Fusarium spp. Germination tests (in-kind contribution) were also performed on the seed to quantify seed quality and correlate it with contamination and/or infection levels. Analysis of the fungal assay results has been initiated, but germination tests are still ongoing. Initial Fusarium levels (on cones) indicates large variability even from the same species and the same facility. Determination of treatment differences will play a key role in developing protocols. Initial results indicate that the majority of Fusarium appears as a seed contaminant, but internal Fusarium was found in some seedlots at some stages. It is clear from the results that debris can be a large source of Fusarium. This has implications to the handling and disposal of debris in a timely fashion. Results indicate that kilning can reduce Fusarium levels, but kiln temperatures used (30-40°C) do not totally eliminate Fusarium from cones, debris or seed. A further examination of type of debris and trends will allow for a prioritization of processing steps for the reduction in seed-borne Fusarium. Following a full analysis of the data, review of observations and discussions with collection and processing personnel a set of protocols for the reduction in seed-borne Fusarium will be developed. Keywords: Fusarium; Seed-borne pathogens; Disease; cone processing; seed processing; conifers. David Kolotelo.
Kolotelo, David. 2003. Development of protocols to reduce the impact of seed-borne fungal disease through the identification of cone and seed processing steps characterized with intensification of seed-borne fusarium species. Forest Investment Account (FIA) - Forest Science Program. Forest Investment Account Report. FIA2003MR328