Awned and awnless stevia (Stevia rebaudiana) seeds of seven different lots produced in
Maringá - PR region and stored for different periods of time were assessed for occurrence of Alternaria
steviae and A. alternata and their transmission to seedlings. The blotter test with freezing was used to detect
the fungi. Sowing seeds were carried out in vermiculite substrate in greenhouses and the seedlings were
assessed after 15 days. The incidence of A. steviae and A. alternata varied in a range of zero to 3.5% and
7.3% to 86.3%, respectively. Transmission varied of 4.5% to 43.5%. Pure culture isolates of the two fungi
obtained from necrotic seeds and seedlings were pathogenic to the three months old stevia plants. Seed lots
stored for 60 to 180 days showed a reduction in infection by both fungi (varying of 86.3% to 46.8%). Nonawned
seeds showed higher A. alternata infection levels (53.8% to 82.8%) when compared with awned
ones (7.3% to 14.8%). Transmission varied from 4.5% to 43.5% and was positively correlated with the
presence of A. alternata in the seeds (54%). A reduction in the germination percentage, varying from 40.5%
to 16.8%, was observed with the increase in storage time.