Seed-borne fungi of chilli (capsicum frutescens) and studies on the seed transmission of colletotrichum dematium in the coastal savannah zone of Central Region of Ghana

Abstract

The study was carried out to assess the influence of Colletotrichum dematium one of the major causes of pepper diseases on the declining yield of pepper in the Ajumako Enyan Essiam district of the Central Region and to find the extent of transmission through different inoculation methods. Three fruit types (riped, unriped and dropped) were collected from six farms across four locations (Akuamase, Nkodwo, Esikado and Mando) and another sample which was made up of only riped fruits was taken from the Mankessim market after which the seeds were extracted. This gave a total of 19 samples. Seed vigour, germination and health tests were conducted to assess the quality of the extracted seeds. Two media (sand and blotter) were used to assess the percent vigour and germination in a Completely Randomised Design in the laboratory. A transmission study was carried out to assess the extent of transmission of Colletotrichum dematium through four methods of inoculation (stem injection, leaf inoculation, flower inoculation and control) in a Randomised Complete Block Design with 4 replications. There were significant differences for both mean percent vigour (8.18% and 5.29%) and mean percent germination (30.04% and 14.17%), for sand medium and blotter paper respectively. A total of 35 species of fungi belonging to 17 genera were isolated from the host. Only flower inoculation with Colletotrichum dematium resulted in seed transmission. Unriped fruits should not be collected for seed extraction for planting purposes because they have high seed mycoflora infection.