Mycroparasitic effect of trichoderma harzianum rifai against cephalosporium acremonium corda

ABSTRACT

Trichoderma harzinuam was found to parasitize Cephalosporiurn acremonium, the incirant of Cephalosporium-wilt disease of gain sorghum. Inhibition and death of the host hyphae were brought about by close contact. T. harzianurn penetrated and grew within the hyphae of the host, C. acremonium. Abundant sporulation of T. harzianum occurred on the colony of the host. Culture filtrates obtained from T. harzianum isolates showed a toxic effect on C. acremontium mycelial growth and inhibited it by more than 35% compared with the control. Sucrose and glucose [as carbon sources], ammonium tartrate and ammonium nitrate [as nitrogen sources], acidic pH and low C/N ratio were the most favourable factors for mycoparasitism. Based on a preliminary pot experiment, the possibility of controlling the disease by soil inoculationwith T. harzianum is suggested. Adding T. harzianum to C. acremonium infested soil decreased the incidence of the disease significantly