Detection, Identification and Management of Seed-borne fungal Pathogens on farmer saved Soybean (Glycine max (L.) Merrill) seeds in Ghana

Abstract

Soybean is infected by a wide range of diseases, many of which are seed-borne. Infection by seedborne pathogens leads to seed rot, low seed germination, low seedling vigour and reduced plant growth as well as marketability. This study investigates seed-borne fungal pathogens that are associated with farmer saved soybean seeds and identify best seed treatment for controlling them to enhance seed quality. Seed-borne fungal pathogens on farmer-saved seeds of soybeans was investigated by examining a total of eleven (11) seed samples from two districts (Saboba and Yendi) in the Northern region and one from CSIR-Savanna Agricultural Research Institute (CSIR-SARI). A total of nine fungi genera were identified to be associate with the soybean seeds including pathogenic Cercospora spp., Alternaria spp., Fusarium spp., Macrophomina phaseolina and saprophytic Aspergillus flavus, Aspergillus niger, Penicillium spp., Curvularia spp. and Rhizopus stolonifer. Rhizopus stolonifer (21.5%) and Aspergillus niger (7.0%) revealed the highest and lowest prevalence respectively. Treatment of soybean seeds with Monceren GT 390 FS, Insector T 45, Garlic extract and Neem seed extract over a period of 90 days resulted in a decrease in fungal prevalence as well as improved seed germination and seedling vigour. Pot experiment conducted to determine pathogenicity of Microphomina phaseolina, Cercospora spp., Aternaria spp. and Fusarium spp. proved to be pathogenic. These findings indicate that farmers saved soybean seeds in Ghana is fungal infected and seed treatment alleviates the destructive effect of these microbes, thus enhancing seed quality and promoting food security in Ghana.