Diversity of floricolous yeasts and filamentous fungi of some ornamental and edible fruit plants in Assiut area, Egypt

Abstract

The floricolous yeasts and filamentous fungi of 44 samples of flowers from both ornamental (20 samples) and edible fruit plants (24 samples) were evaluated. The general isolation medium DRBC supported more fungal species diversity in both flowers, than the xerophilic media (DG18 and MY50G). The highest numbers of fungal propagules were recovered on DG18 from flowers of ornamental plants, while the lowest on MY50G from flowers of edible plants. Yeasts constituted small proportion of propagules from the two flower types on the three media. Yeasts were represented by 18 genera and 26 species. Metschnikowia (3 species, from which M. reukaufii and M. viticola), Candida (4 species, from which C. riodocensis and C. vaccinia), Cryptococcus (C. albidus var. kuetzingii), Meyerozyma (M. guilliermondii), Naganishia (N. diffluens), Rhodotorula (2 spp., R. mucilaginosa), and Vishniacozyma (2 spp., V. carnescens) were infrequently encountered on the three media, beside Filobasidium (2 species), Galactomyces (G. candidus), Papiliotrema (P. flavescens), Pichia (P. kluyveri), and Sporidiobolus (S. metaroseus) which were recorded on two media. Some other yeast species were recovered only from one flower type but not from the other. Cladosporium (10 species) was the most common genus (100 % of samples from both types of flowers), accounting from 66.45 % to 87.25 % of total fungi. C. herbarum, C. cladosporioides, C. oxysporum, and C. sphaerospermum were recovered in high frequency from both types of flowers, but C. herbarum yielded the major proportion (61.23 % to 75.77 % of total fungi). Other filamentous fungi e.g. Alternaria (19 species, from which A. alternata and A. chlamydospora), Aspergillus (47 species, from which A. flavus, A. niger, and A. terreus), Penicillium (29 spp., P. chrysogenum and P. olsonii), Fusarium (12 spp., F. incarnatum, F. solani, and F. verticillioides), and Stemphylium (3 species, S. botryosum and S. sarrciniforme) were found contaminating all flowers on almost all isolation media.