Weed hosts of major legume viruses in Niger State, Southern Guinea Savanna of Nigeria

Abstract

Field surveys were conducted during the 2015 cropping season to identify and determine the distribution of legume viruses in Niger State, Nigeria. A total of 27 locations were visited during the surveys. Leaves were collected from weed plants showing virus and virus-like symptoms in fields of cowpeas, groundnuts and soyabean. Samples were also collected from asymptomatic plants within the vicinity of infected plants. The antigen coated plate - enzyme linked immunosorbent assay (ACP –ELISA) method was employed for virus detection in the collected leaf samples. Results showed that Blackeye cowpea mosaic virus (BICMV), Cowpea mild mottle virus (CPMMV) and Cowpea mottle virus (CPMoV) were the viruses detected. Thus Aeschynomene indica, Amaranthus caudatum and Centrosema pubescens were positive to BICMV; while Aspilia africana, Cleome viscera, Euphorbia hirta and Heterotis rotundifolia were hosts of CPMoV and CPMMV was detected in Chenopodium amaranticolor, Desmodium scorpiurus, and Vicia faba. The detection of these viruses in weed species in the surveyed areas indicates their importance in the ecology, survival and the significant role they play in the epiphytology of the various virus diseases. The occurrence of BICMV, CPMoV and CPMMV in these weed species is believed to be the first report in the study area.