ASSESSING GENETIC DIVERSITY AND PHYLOGENETIC LINKS AMONG VIRUSES AFFECTING YAM (DIOSCOREA SPP.) IN NIGERIA'S GUINEA SAVANNA ZONE
Abstract
Yam (Dioscorea spp.) holds immense agricultural significance in sub-Saharan Africa, particularly in Nigeria, where it stands as the primary root crop in terms of cultivation area, production volume, and economic value. However, yam cultivation faces persistent challenges attributed to pest-related yield losses, including insects, diseases, and weeds. Among these obstacles, viral diseases have emerged as a substantial concern due to their detrimental impact on yam propagation.
The primary mode of yam multiplication involves vegetative planting of cuttings or tuber pieces (setts), resulting in the accumulation and transmission of viral diseases. Various viral pathogens from the Potyvirus, Potexvirus, Badnavirus, Cucumovirus, and Caviavirus genera infect yam species, inducing symptoms such as mosaic patterns, chlorosis, stunting, and distortion. Of particular importance in sub-Saharan Africa is the Yam mosaic virus (YMV) within the Potyvirus genus.
This abstract highlights the prevalence and consequences of viral infections in yam cultivation, especially in regions responsible for over 90% of global yam production. It underscores the need to address the epidemiology and control of yam viruses, emphasizing the role of uncontrolled introduction of infected yam germplasm in spreading these pathogens. Understanding and managing viral diseases are crucial steps toward ensuring the sustainability and productivity of yam farming in sub-Saharan Africa.
Keywords:
Yam cultivation, Viral diseases, Yam mosaic virus (YMV), Yam propagation, Sub-Saharan AfricaDownloads
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Copyright (c) 2023 Dr. Shatu Wudiri Asala , Dr. Ibrahim Yusuf Mohammed
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