Assessing the Pathogenic Ability of Six Species of Fusarium Genus on Onion Variety in Burkina Faso

Prema 178 onion variety is widely used in production in Burkina Faso. It is greatly appreciated but susceptible to basal rot. This study aimed to evaluate the pathogenic ability of six strains of Fusarium genus identified in Burkina Faso on onion. Seeds, seedlings and bulbs were used for the test. A conidial suspension of each strain was made in tubes and adjusted to 1 × 106 conidia/ml with distilled water for the different tests. Germination test in the laboratory and greenhouse showed that all treatments with the strains of Fusarium oxysporum f. sp. cepae, F. solani, F. falciforme, F. acutatum, F. proliferatum and F. sp. induced failure to emerge and showed a significant difference with the control. The different strains also induced stunting rates of coleoptile growth. Fusarium oxysporum f. sp. cepae, F. acutatum, F. proliferatum, F. falciforme and F. solani were very aggressive, as they recorded above 50% damping-off rates. The test on the bulbs revealed that the strains were classified into two groups. The first consists of F. oxysporum f. sp. cepae, F. solani, F. falciforme, F. acutatum, which caused rots with respective lengths from 2.06;1.48;1.84;1.46 and 2.12 cm, thus very aggressive according to Ghanbarzadeh scale. The second is formed by F. proliferatum which recorded 0.90 cm of rot length, thus moderately aggressive. It would be appropriate to suggest a sustainable management method for these pathogens in order to improve the yield of onion production.