Abstract
Activity of five methanolic plant extracts obtained from Lantana camara, Salvadora persica, Thymus vulgaris, Zingiber officinale and Ziziphus spina-christi were investigated for their antifungal effect on tomato phytopathogenic fungi (Fusarium oxysporum, Pythium aphanidermatum and Rhizoctonia solani) the causative agents of tomato damping-off diseases. Three of five plant extracts were effective against tomato phytopathogenic fungi. T vulgaris and Z. officinale extracts were strongly active and showed fungistatic and fungicidal activities against the phytopathogenic fungi with MIC of 4 mg/ml and MFC of 8 mg/ml except E oxysporum which was less sensitive and its MFC reached to 16 mg/ml of Z. officinale extact. On the other hand, S. persica extract showed a moderate antifungal activity while L. camara and Z. spina-christi were not effective against tomato phytopathogenic fungi except P aphanidermatum which was completely inhibited at 10 mg/ml of L. camara extract. Carbendazim fungicide was more effective than all methanolic plant extracts inhibiting mycelial growth of all phytopathogenic fungi at 8 ppm and a huge concentration reached to 8 mg/ml of the effective plant extract was required to attain the same effect. Analysis of the effective plant extracts by GC/MS revealed that T vulgaris extract was mainly composed by thymol (38.73%), carvacrol (19.31%), a-cimene (10.13%) and a-terpinolene (5.94%) while Z. officinale was mainly composed by Gingerol (46.85%), cedrene (8.39%), zingiberene (7.41%) and a-curcumene (7.32%) respectively. These effective plant extracts may contribute to development of potentially effective and environmentally safer alternative fungicide to control tomato damping- off phytopathogenic fungi.