Resistance of strawberry (fragaria hybrids) to mycosphaerella fragariae (TUL.) LIND. (Ramularia tulasnei SACC)

Abstract

49 strawberry clones were tested for the reaction to the natural incidente of Ramularia tulasnei in field condictions, in Piracicaba, São Paulo State. The evaluation were done using a scale of 1 (denoting no infection) to 6 (indicating a severe infection) in the phase of highest severity of the disease; the clones were classified in resistants (1.00 to 2.30), moderately resistants (2.31 to 3.70), and susceptibles(3.71 to 5.00). 11 resistant clones, 31 moderately resistant, and 7 susceptible ones were identified. The resistant clones were "1-2008" (grade 1.00 ± 0.00), "IAC-2713", "Camanducaia (IAC-3530)", "A. Brucknner (1-2492)", "IAC-3113 x (IAC-2712 x 1-2008-1)-10", "IAC-4326", "IAC-3530 x IAC-2747-2", "Konwoy (1-3846)", "Atibaia (IAC--4325)", "IAC-4896-4", and "IAC-4749"; the most susceptible one was "Jundiai (IAC-4204)" (grade 5.00 ± 0.41).