Cultural, molecular and pathogenic variability of Mycosphaerella pinodes and Phoma medicaginis var. pinodella isolates from dried pea (Pisum sativum)in France

The characteristics of 50 isolates of Mycosphaerella pinodes and 17 isolate s of Phoma medicaginis var. pinodella, originating from several regions of France where ascochyta blight is prevalent, were investigated using cultura l, physiological, molecular and pathogenicity analyses. M. pinodes was dist inguished from P. medicaginis var, pinodella on the basis of presence of ps eudothecia, a higher proportion of larger, bicellular conidia, compared wit h the smaller, predominantly unicellular conidia of P. medicaginis var, pin odella, and a slower linear growth rate on agar under a 12-h light regime. RAPD analysis clearly distinguished the two species, which had low intraspe cific variability. Although both species gave identical symptoms, they coul d be distinguished by their incubation period and aggressiveness, respectiv ely, shorter and higher for M. pinodes. Virulence tests gave no definitive evidence for the existence of pathotypes among the M. pinodes isolates. Two unidentified isolates had similar characters to both M. pinodes and P. med icaginis var. pinodella in some features but were distinguished from them b y their RAPD patterns.