The Pasmo Pathogen of Flax, Investigating Potential Resistance and Characteristics of Infection

Evan Gillis¹, Khalid Rashid², Lakhdar Lamari¹

Discussion

All preliminary results obtained coincide well with the findings of Sackston, 1949.  The fact that S. linicola pycnidial organization begins to occur before 6 DAI leads to the possibility that the structures may reach maturity and have the ability to produce spores by 8-10 DAI.  This behavior may present a problem to flax producers because this is a relatively fast production of secondary inoculum compared to some other Septoria pathogens such as Septoria tritici blotch of wheat, where the congregation of hyphae to form pycnidia only became apparent at 12 days (Cohen and Eyal, 1993).  When the pathogen requires fewer days to produce inoculum then it can complete more cycles in a growing season causing rapid spread in a field and increased losses.

The results from commercial cultivars AC McDuff and AC Emerson will be compared to selection 7878 to determine if this selection, which performed relatively well under field conditions in experimental plots shows any signs of resistance at the microscopic level. This information could include deposition of any compounds or metabolites such as lignin or callose at infection sites or impeded mycelium or pycnidium growth and development.  The knowledge gained about the host-pathogen relationship between S. linicola and flax will help better understand the association they have with each other and aid in the development of resistant or partially resistant varieties.