Control of Fusarium Wilt of Tomato Caused byFusarium oxysporumF. Sp. Radicis-Lycopersici Using Mixture of Vegetable andPosidonia oceanicaCompost

Abstract

A compost of vegetable waste andPosidonia oceanicamixture (70 : 30% vol : vol) was testedin vitroandin vivofor its efficacy againstFusarium oxysporumf.spradicis-lycopersici(Forl), the causal agent of Fusarium wilt of Tomato (Lycopersicon esculentumcv. chourouk).The incorporation of non-sterilized VPC in the culture medium showed potent antifungal activity against Forl and complete inhibition of mycelium growth was observed for all the tested compost rates (0.5, 1, 2, 4, 6, 8, 10, 15 and 20%). However, only the highest rates (15 and 20%) of a sterilized suspension of VPC were effective in preventing mycelial growth. Nine indigenous bacterial strains isolated from VPC exhibited antagonism against Forl. Based on 16S rDNA sequence analysis, the isolates were assigned toBacillus sphaericus(B12 and BS2),Pseudomonas putidaPPS7 andBurkholderia gladioliBuC16. Under green house condition, seed inoculation by B12, BS2, PP7 and BuC16 strains protected significantly tomato againstFusarium oxysporumf.spradicis-lycopersici(Forl) attacks.