Biological activity of Callistemon viminalis and Chenopodium ambrosioides ethanolic extract on banana Fusarium wilt in screen house conditions

Abstract

Plantain (Musa spp.) is one of the most important food crops in Cameroon, however its production is threatened by many fungal diseases, such as banana Fusariumwilt a siol born fungal causing heavy losses.The objective of this work was to evaluate the biological activity of Callistemon viminalis and Chenopodium ambrosioides ethanolic extract against this disease in screen house. 42314Infected roots and leaves samples were collected from banana plantations in five localities of the West Region of Cameroon and brought to the laboratory for pathogen isolation and identification. Soil samples collected from the wilted banana rhizosphere were analysed to determine the edaphic factors influencing the growth of the pathogen. Two incoculation techniques were tested in the screen house prior to the pathogenicity test and the bioassay. All F. oxysporumisolates identified were pathogenic and the Foumbot isolate was more agressive. Clay-rich and slightly acidic soils favored the growth of F. oxysporum, while soils rich in organic matter and phosphorus inhibited its development. The drenching inoculation technique was more favorable for the inoculation of the parasite on banana seedlings. Ethanolic extracts of C. viminalis and C.ambrosioides, significantly reduced disease incidence and severity. Efficiency of Callistemon ethanolic extract (20 mL) was highly and significantly comparable to Eagrow Care (20 mL) in controlling banana Fusarium wilt. Ethanolic extracts of C. viminalisand to some extend C.ambrosioides could serve as a basis for a biofungicide formulation as alternative to chemical fungicides. Complementary molecular and ecological studies are essential to optimize disease management strategiesBanana plantain, Biocontrol, C.viminalis, Drenching inoculation technique ethanolic extract, Fusarium wilt