Evaluation of seed health testing methods for the detection of seed-borne fungi of African yam bean, Sphenostylis stenocarpa

Abstract

The efficiency of four seed health testing techniques namely the blotter, deep- freezing blotter, ragdoll and agar plate methods in detecting seed-borne fungi of African yam bean, Sphenostylis stenocarpa (Hochst ex. A. Rich) Harms seeds was evaluated. The blotter method was found to be the most suitable testing technique for detecting Aspergilus flavus, A niger, A terreus, A. ochraceus, Botryodiplodia theobromae, Colletoritchum dematium, C. gloeosporiodes and Curvularia lunata in seeds pre-treated with 1 % available chlorine for 5 minute as well as in untreated seeds. The deep-freezing blotter method was superior to the other methods in detecting Fusarium moniliforme, F. semitectum, Chaetomium sp. and Cephalsorium sp. The incidence of Macrophomina phaseolina and Penicillium spp. were recorded more in the agar plate method than in the other fungi recorded but gave highest percentage seed germination in both untreated and chlorine pre-treated seeds in all the four sampled tested.

Keywords: Sees health, testing techniques, seed-borne fungi, African yam bean.