Effect of antifungal botanical extracts on seed-borne fungi prevalence and germination of Terminalia ivorensis seeds in Ghana

Abstract

The use of synthetic fungicides for the management of seed-borne pathogens are detrimental to human health and the environment. In view of this research was conducted to assess the effect of antifungal botanical extracts (garlic, neem and Senna alata) on seed-borne fungi prevalence and seed germination of Terminalia ivorensis seeds. Two major seed-borne fungi of two genera namely Aspergillus niger and Colletotrichum sp. were isolated from the seeds. There was a hundred percent incidence of seed-borne fungi infection of Terminalia ivorensis seeds. Aspergillus niger was predominant with an incidence of 91.7% while Colletotrichum sp. had an incidence of 8.3%. There were significant differences between treatments with respect to total seed-borne fungi prevalence. Seeds treated with Senna alata aqueous extract showed the highest 100.0% prevalence of total seed-borne fungi followed by seeds treated with neem (75.0%) whilst seeds treated with aqueous garlic extract recorded the least (8.3%) total seed-borne fungi prevalence. The highest (100.0%) prevalence of Aspergillus niger was recorded by seeds treated with Senna alata whilst the least (8.3%) recorded in seeds treated with garlic. Colletotrichum sp. was only prevalent on seed treated with Mancozeb 80% WP at 8.3%. Significant variations were observed between treatments regarding germination percentages of Terminalia ivorensis seeds. Seeds treated with garlic extract recorded the highest (50.0%) germination percentage whilst the lowest (21.7%) recorded by Senna alata. Treating forest tree seeds with garlic extract before sowing could inhibit the growth of fungal pathogens and therefore improve germination.