Onion (Allium cepa L.) is the second most important vegetable crop in Burkina Faso and provides an important source of income for those involved in the sector. However, producers are facing significant pre-harvest and...Onion (Allium cepa L.) is the second most important vegetable crop in Burkina Faso and provides an important source of income for those involved in the sector. However, producers are facing significant pre-harvest and post-harvest losses. To date, knowledge of major diseases of the crop is limited, limiting the development of effective control strategies. The objective of this study was to test the pathogenicity of some species of Fusarium. To this end, 33 fungal isolates collected from onion plants in 17 localities and belonging to five Fusarium species were used to inoculate onion seeds and bulbs to determine the pathogenic species responsible for damping-off on seedlings and basal bulb rot in Burkina Faso. The virulence of pathogenic isolates was determined according to the percentages of seedling damping-off evaluated 28 Days After Sowing, and the extent of rot in millimetres on inoculated bulbs. The evaluation of isolates on seedlings revealed that the most pathogenic isolates belong to the species F. proliferatum (I29, I21, I37, I33, I31), F. thapsinum (I35) and F. solani (I38) which resulted in 58.33% - 70.83% of seedling damping-off. The most pathogenic isolates on bulbs belong to the species F. proliferatum (I4, I29, I32) and F. oxysporum (I52, I50, I16) which caused 21.67 to 25 mm of rot on bulbs. Isolate I29 was very virulent on both seedlings and bulbs. The isolates of F. fujikuroi species were all low pathogenic on seedlings but one of them, (I27), expressed average pathogenicity on bulbs.展开更多
Many fungi limit onion production in Burkina Faso. This study aims to identify the main Fusarium species associated with onion plant in field in order to determine those involved in seedling damping-off and bulb rot, ...Many fungi limit onion production in Burkina Faso. This study aims to identify the main Fusarium species associated with onion plant in field in order to determine those involved in seedling damping-off and bulb rot, and develop adequate management strategies of these diseases. For this purpose, 36 isolates of Fusarium were isolated from onion plants in 17 sites and subjected to molecular analysis and biometric characterization. The results revealed that the isolates belong to five Fusarium species: Fusarium oxysporum (44.44% of the isolates), Fusarium proliferatum (41.66%), Fusarium solani (5.55%), Fusarium fujikuroi (5.55%) and Fusarium thapsinum (2.77%). Fusarium oxysporum, F. proliferatum, F. solani and F. fujikuroi had faster mycelial development, with a growth rate of 7.72 - 8.27 mm/d, than F. thapsinum (6.52 mm/d). Conidia of F. oxysporum, F. proliferatum and F. solani were longer (4.74 - 5.96 μm) than those of F. fujikuroi and F. thapsinum (3.20 - 4.04 μm). Fusarium solani and F. oxysporum, respectively, had the largest and most partitioned conidia.展开更多
基金the Congregation of the Sisters of the Immaculate Conception of Ouagadougou(S.I.C.O)and the Institute of Environment and Agricultural Research(INERA)for their financial support for this work.
文摘Onion (Allium cepa L.) is the second most important vegetable crop in Burkina Faso and provides an important source of income for those involved in the sector. However, producers are facing significant pre-harvest and post-harvest losses. To date, knowledge of major diseases of the crop is limited, limiting the development of effective control strategies. The objective of this study was to test the pathogenicity of some species of Fusarium. To this end, 33 fungal isolates collected from onion plants in 17 localities and belonging to five Fusarium species were used to inoculate onion seeds and bulbs to determine the pathogenic species responsible for damping-off on seedlings and basal bulb rot in Burkina Faso. The virulence of pathogenic isolates was determined according to the percentages of seedling damping-off evaluated 28 Days After Sowing, and the extent of rot in millimetres on inoculated bulbs. The evaluation of isolates on seedlings revealed that the most pathogenic isolates belong to the species F. proliferatum (I29, I21, I37, I33, I31), F. thapsinum (I35) and F. solani (I38) which resulted in 58.33% - 70.83% of seedling damping-off. The most pathogenic isolates on bulbs belong to the species F. proliferatum (I4, I29, I32) and F. oxysporum (I52, I50, I16) which caused 21.67 to 25 mm of rot on bulbs. Isolate I29 was very virulent on both seedlings and bulbs. The isolates of F. fujikuroi species were all low pathogenic on seedlings but one of them, (I27), expressed average pathogenicity on bulbs.
基金the Congregation of the Sisters of the Immaculate Conception of Ouagadougou(S.I.C.O.)and the Institute of Environment and Agricultural Research(INERA)for their financial support for this work
文摘Many fungi limit onion production in Burkina Faso. This study aims to identify the main Fusarium species associated with onion plant in field in order to determine those involved in seedling damping-off and bulb rot, and develop adequate management strategies of these diseases. For this purpose, 36 isolates of Fusarium were isolated from onion plants in 17 sites and subjected to molecular analysis and biometric characterization. The results revealed that the isolates belong to five Fusarium species: Fusarium oxysporum (44.44% of the isolates), Fusarium proliferatum (41.66%), Fusarium solani (5.55%), Fusarium fujikuroi (5.55%) and Fusarium thapsinum (2.77%). Fusarium oxysporum, F. proliferatum, F. solani and F. fujikuroi had faster mycelial development, with a growth rate of 7.72 - 8.27 mm/d, than F. thapsinum (6.52 mm/d). Conidia of F. oxysporum, F. proliferatum and F. solani were longer (4.74 - 5.96 μm) than those of F. fujikuroi and F. thapsinum (3.20 - 4.04 μm). Fusarium solani and F. oxysporum, respectively, had the largest and most partitioned conidia.
