دراسة التاثير التثبيطي لبعض المبيدات الفطرية وفطر المقاومة الاحيائية Trichoderma harzainum ضد الفطر الممرضAlternaria solani

Abstract

The research included testing the effect of fungicide topsen , chevalier and pesticide ethanol in the growth of pathogenic fungus Alternaria solani . The effect of these pesticides in the radial growth and dry weight of this fungus was investigated in addition to the effect of antagonism of Trichoderma harzainum against A. solani under different environmental conditions of ( pH and temperature ). The results showed that all pesticides used have had a significant effect in inhibiting the growth of A. solani in PDA compared with that in untreatment one (0.05). Ethanol was grates effect in the inhibition of radial growth and dry weight of A.solani and using 10,15,20 mg 10 ml concentrations of pesticides in partial at 20 concentration with an average diameter of A.solani (0, 1.1, 1.8 cm) of pesticides ethanol, chevalier and topsen respectively. As well as the best concentration is 20 mg10 ml pesticide in reducing the rate of the dry weight which amounted to (0, 0.18, 0.14) g of pesticides respectively. Also studied the efficiency effect of the fungus Trichderma harzianum against the growth of pathogenic fungus A.solani and different environmental conditions has been given the highest capacity at 6 pH degree and 30 Cº and the effect was less at pH 8 and at a temperature of 20 Cº