Effect of Some Chemical and Biological Treatment Against the Fungal Alternaria solani

Abstract

This study was carried out to test the effectiveness of two chemical pesticides Folio gold 537 SC and the mixture of Bravo50 SC) + (Valbon71.75 WG and the two Bio control agent fungal Trichoderma harzianum and bacterial Bacillus subtilis individually against the fungus Alternaria solani the causal agent of Early Blight disease, laboratory study was conducted to test the effectiveness of chemical and biological factors in inhibiting the growth of pathogenic fungus, The results showed an antagonism property activity of bacterial bio-control agent. B.subtilis against the pathogenic fungus A.solani in the media culture , B.subtilis has caused complete inhibition in the growth of pathogenic fungus mycelia reached 100% at at dilution of 5.4 × 8-10, also fungal bio-control agents T.harzianum showed a high ability of antagonism to the growth and development and reproduction of the pathogen A.solani. Results indicated a high compatibility between the fungal and bacterial bio agents T.harzianum and B.subtilis with no any antagonism effect of the bacterial bio agent B.subtilis in the growth and development of biological control fungus T.harzianum. Results showed that the fungicide Folio gold 537 SC achieved a complete inhibition 100% of pathogenic mycelial growth in all tested concentrations (RD -50) (RD) (RD + 50), and the mixture of (Bravo + Valbon) has achieved A significant inhibition for pathogen mycelial growth by of pathogen at 81.46 and 92.22 and 96.23% for the three concentrations respectively.