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The teleomorph of Ascochyta fabae has been recorded for the first time on overwintering bean straw of Viciafaba in Cambridge. Single ascospores gave rise to typical cultures of A. fabae, the conidia of which infected faba bean plants to give ascochyta blight. Comparison with similar fungi described from Vicia spp. indicated that this is an undescribed species. The name Didymella fabae Jellis & Punith. is introduced for this teleomorph and its significance in the epidemiology of the disease is discussed.

The morphological, molecular and pathological characters of 34 isolates identified as Ascochyta pinodes, A. phaseolorum, and Phoma medicaginis var. pinodella were determined. Initial molecular findings, based on PCR fragment size and RFLPs of sections of the mitochondrial genome, the rRNA gene cluster and the beta-tubulin gene complex, were further investigated by sequencing of the total rRNA ITS regions. Isolates were homogenous for all characteristics determined, with the exception of conidial size and septation, and RFLPs of AT rich (presumptive mitochondrial) DNA. The results suggest that the isolates represent host preferential forms of a single taxon, and this finding is discussed in relation to the known teleomorphs and reference material of the species studied.

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