Resistance of strawberry cvs. to Phytophthora fragariae var. fragariae
Experiments were carried out in North Carolina (US) to study the colonization of roots of strawberry cultivars with different levels of susceptibility to Phytophthora fragariae var. fragariae (EPPO A2 quarantine pest). Roots of the different cvs. were examined 2, 4, 6, 8 and 10 d after inoculation with the fungus. It was found that P. fragariae var. fragariae colonized the roots of partially resistant cvs. much slower than those of susceptible cvs. and that it developed fewer reproductive organs. Very few or no sporangia were formed and thus, with no production of secondary inoculum the strawberry plants were able to grow and produce good crops.
Sources
Milholland, R.D.; Daykin, M.E. (1993) Colonization of roots of strawberry cultivars with different levels of susceptibility to Phytophthora fragariae.
Phytopathology 83, 538-542.