“Ion Ionescu de la Brad” University of Agricultural Sciences and Veterinary Medicine, Iaşi
Abstract
Monilinia fructigena is the pathogen responsible for the appearance of brown rot and mummification of apple fruit
present anywhere this species is grown. In Romania, the fungus attack is frequently in the apple orchards every year,
depending on the environmental conditions, variety resistance, pathogen control management. The antifungal activity
aainst this pathogen of steroidal glycoalcaloids extracted from Solanum species was tested in vitro. The steroidal
glycoalkaloids considered were: solanine, solanidine, tomatine, solamargine, chaconine. Of these, a structural group,
encoded GLY, was selected as one of the active components of a patented biofungicide. It was tested in concentrations
of 0.1%, 0.5% and 1% and compared with the control. The biological material was represented by the isolated
Monilinia fructigena (Mf 7), collected on apple fruit, the Idared variety, originated from RIFG Maracineni. The fungus
did not develop in the first 3 days of incubation in any of the experimental variants. After 6 days of observation, the
fungus developed at variants of GLY 0.1%, GLY 0.5% and control. The maximum mycelial diameter was determined
in the control variant with 73.3 mm after 12 days of observation. In the GLY0.1% variant the diameter of the colony
was 50 mm and in the GLY 0.5% variant the diameter of the fungus colony reached 8.2 mm, after 12 days of
observation. In GLY 1% variant fungus did not develop throughout the observation period. Efficacy was maximal (E =
100%) in the GLY1% variant, followed by the GLY0.5% variant, with the efficacy of 88.8%. The EC 50 and EC 90
values were 0. 21% and 0.75% for the data obtained after 12 days of observation
