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In the spring season of 2011, fungal isolation under laboratory conditions from senescent strawberry
plants of Festival variety collected from a farm in Dlalha (Moulay Bousselham, Northwestern Morocco)
revealed the presence of two isolates of Pestalotia longisetula. The Koch’s postulate was verified by
inoculating healthy leaves of Festival and Sabrina strawberry varieties using mycelia discs and conidia
suspension. Severity index on Festival and Sabrina leaves reached respectively 85 - 77.5% and 73.2 -
69.8% for inoculation by the first technique. The inoculation by the second technique revealed that the
severity index of the two isolates of P. longisetula (PD and PF) were superior on leaves of Festival,
respectively 68 - 63.1% against 56.8 - 50.5% on Sabrina leaves. The lowest conidia production was
observed on Sabrina leaves, inoculated with PF isolate conidia suspension (1.58 105 conidia. cm-2).
Elevated conidia production was recorded on Festival leaves, 2.81 105 conidia. cm-2, inoculated with the
PD mycelial disc. This pathogen was also able to infect ripe strawberries of Festival and Splander
varieties. The PF isolate showed the greatest capacity to induce superficial and depth lesions respectively
16.1 and 16.6 mm and to produce conidia, 9.4 105conidia. cm-2, on Splander variety which seems to be
most susceptible to infection. This was the first report of P. longisetula showing the capacity to infect
strawberry leaves and fruits in Morocco.
Keywords: Pestalotia longisetula, Fragaria ananassa, leaves, strawberries, pathogenecity, Morocco.