ANTAGONISM CAPABILITY IN VITRO OF TRICHODERMA HARZIANUM AGAINST ALTERNARIA ALTERNATA ON CERATONIA SILIQUA

Zahra Ibrahim El-Gali*

ABSTRACT

The in vitro studies on the antagonism of Trichoderma harzianum on pathogenic fungal Alternaria alternata isolated from carob leaves showing symptoms of brown spot disease grown at north-east Libya, was carried out to test the ability of the antagonist fungus in inhibiting the growth of the plant pathogen using dual culture assay, Trichoderma conidial suspension and Trichoderma filtrate. Direct confrontation of the colonies of T. harzianum with this of the pathogen results in an inhibition and growth arrest at a distance of the parasite. Inhibition and The mycelia of Alternaria showed abnormal morphology under direct influence of Trichoderma. The results of the activity assay of filtrate of the antagonistic fungus at different concentrations on the radial mycelial growth and percent radial mycelial growth inhibition of pathogenic fungus at all concentrations of the antagonist filtrate. Further evaluation of Trichoderma bio-control potential in field condition was recommended.

Keywords: Alternaria alternata, Ceratonia siliqua, Trichoderma harzianum, Biocontrol, Antagonism.