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Using an organically cultivated batch of rye, drum drying (fixed constant maximum grain temperature 62°C; retention time 10.5 minutes) and ordinary continuous drying were compared with regard to effect on baking quality and surviving propagules of yeasts and filamentous fungi. Both techniques dried the grain quickly and efficiently, and no differences in baking quality were found after drying. Drum drying was much more efficient than continuous drying in reducing surface dwelling yeasts and filamentous fungi. The results showed drum drying to be very efficient towards the deoxynivalenol, nivalenol and zearalenone producing Fusarium culmorum and more so than continuous drying. [Copyright &y& Elsevier]

j.c. frisvad, f. lund and s. elmholt. 2004.To examine if molecular amplified fragment length polymorphism (AFLP) fingerprinting of the only ochratoxin A-producing species in European cereals,Penicillium verrucosum, can be used as a method in hazard analysis using critical control points (HACCP).A total of 321 isolates ofP. verrucosumwere isolated from ochratoxin A-contaminated cereals from Denmark (oats), UK (wheat and barley) and Sweden (wheat). Of these, 236 produced ochratoxin A as determined by thin layer chromatography; 185 ochratoxin A-producing isolates were selected for AFLP fingerprinting. A total of 138 isolates had unique AFLP patterns, whereas 52 isolates could be allocated to small groups containing from two to four isolates with similar AFLP patterns. A total of 155 clones were found among the 185P. verrucosumisolates, thus 84% of the isolates may represent different genets ofP. verrucosum. As the few isolates that were grouped often came from the same farm, and those groups that contained AFLP-identical isolates from different countries were morphotypically different. On single farms up to 35 clones were found. The few groups of ramets from the same genet indicated that a HACCP approach based on clones may require a very large number of AFLP analysis to work in practice, we recommend basing the HACCP approach on the actual speciesP. verrucosum. A more detailed characterization should rather be based on the profile of species present at different control points, or analysis of the mycotoxins ochratoxin A and citrinin in the isolates. Examination of 86 isolates with HPLC and diode array detection ofP. verrucosumshowed that 66% produced ochratoxin A, 87% produced citrinin, 92% produced verrucin and 100% produced verrucolone.Among 184 ochratoxin A-producingPenicillium verrucosum, 155 clonal lineages were indicated by AFLP fingerprinting, indicating a high genetical diversity, yet the speciesP. verrucosumis phenotypically distinct and valid.AFLP fingerprinting ofPenicillium verrucosumindicates that genetic recombination takes place in this fungus. [ABSTRACT FROM AUTHOR]

Phytophthora drechsleri f. sp. cajani (Pal et al) Kannaiyan et al. causes stem and leaf blight in pigeon pea (Cajanus cajan [L.] Millsp.) in India. The asexual phase occurs in artificial culture as well as on the host tissue. Sparse oospore formation has been observed in old cultures. A technique has been evolved in which abundant mature oospores are formed on the leaflets of pigeon pea and also on glass slides using zoospores and mycelial discs on the former but only mycelial discs on the glass slides. The largest number of oospores was formed after incubation for 36 h at 25 °C. [ABSTRACT FROM AUTHOR]