Journal of Pure and Applied MicrobiologyVol. 6 No. 4

Fungitoxic Properties of Some Plant Extracts Against Tomato Phytopathogenic Fungi

Ashraf A. Mostafa1, A.N. Al-Rahmah1, Ahmed Abdel-Megeed1,2, Essam Nageh Sholkamy1, Abdullah A. Al-Arfaj1 and Mohamed S. El-shikh1

1Botany and Microbiology Dept. Collage of Science, King Saud University, P.O. 2455, Riyadh, 1145, Kingdom of Saudi Arabia. 2Faculty of Agriculture (Saba Basha), Alexandria University, Egypt.

Received on 09 October 2012 and accepted on 20 November 2012

 

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 F. 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%), ?-cimene (10.13%) and ?-terpinolene (5.94%) while Z. officinale was mainly composed by Gingerol (46.85%), cedrene (8.39%), zingiberene (7.41%) and ?-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.

Keywords : Fungicides, Plant extracts, Fungitoxic properties.