The effect of plant extracts from Solanum nigrum L. and Avena fatua L. on the growth of some weed species and agropathogenic fungi

Experiments to evaluate 40% and 80% methanol extracts prepared from the aboveground parts of two Solanum nigrum biotypes and from the roots of two Avena sativa biotypes were used to test the growth and development of some weed species and agropathogens. The species collected from different crop fields were Viola arvensis, Chenopodium album, Stellaria media, Papaver rhoeas, and Thlaspi arvense together with the pathogenic fungi Fusarium avenaceum, F. culmorum, and F. oxysporum. Plant morphological changes and significant fresh weight reduction of Viola arvensis were observed when treated with both 40% and 80% extracts. A similar response was found in C. album, but only when plants were treated with an 80% extract obtained from plants of S. nigrum collected from a maize field. The most susceptible to both extracts from A. fatua roots growing in a spring wheat field were C. album and S. media, whereas V. arvensis was only susceptible to the 80% extract. The addition of the extracts obtained from A. fatua to PDA medium at concentrations of 0.1% and 1% contributed to significant reductions in the mycelium growth of all three Fusarium species. The extract obtained from S. nigrum added to PDA medium at 1% concentration slightly stimulated mycelium growth of F oxysporum.