Fungi isolated from tobacco leaves and brown-spot lesions before and after flue-curing.

Discs of tissue excised from ripe nonflue-cured and flue-cured tobacco leaves, harvested on six dates and cultured on three selective media, yielded 21 and 24 genera of fungi, respectively. Of 5,094 fungi isolated from 3,240 pieces of nonfluecured leaf tissue, 89.5% comprised five genera, Alternaria, Cladosporium, Epicoccum, Trichoderma, and Nigrospora. Of 2,494 fungi isolated from 3,240 pieces of flue-cured leaf tissue, 70.9% were Alternaria, Cladosporium Epicoccum, Aspergillus, and Nigrospora. Flue-cured and nonflue-cured brown-spot lesions harvested at two locations yielded 12 and 14 genera of fungi, respectively. Alternaria, Penicillium, Phoma, and Stemphyllium comprised 91.5% of the 2,245 fungi isolated from noncured and 87.1% of the 1,118 fungi isolated from the cured lesions. The number and kinds of fungi obtained from diseased and healthy tissue were reduced but not eliminated by flue-curing.