Virus and virus-like diseases of citrus in West-Africa: an overview

Abstract

Purpose: In sub-Sahara Africa, citrus is mainly cultivated in the coastal countries. It plays important nutritional and socio-economical roles by providing vitamins and minerals to consumers and cash to farmers. The crop is being challenged by many constraints. The purpose of this review is to inventory the virus and virus-like diseases known to infect citrus in the West-Africa up today. Findings: Less attention is given to citrus in West African countries while the crop is imperiled by biotics as well as abiotic constraints. Then, it is threatened by several diseases. Among them, the updated reported virus and virus-like diseases are tristeza, exocortis, citrus psorosis complex, cachexia, stubborn and greening. There is no recent update regarding the incidence, severity, and distribution of those diseases as well as their impact on yield. The biological or molecular characterization of the diseases' causal agents also still lack. Research limitations: There is no effective national or regional plant protection policy; leading to the persistence of citrus diseases and wide-spreading infections. Climate change is enhancing the dilemma. Directions for future research: The sustainable production of citrus in the region requires new plant protection policies and investigations regarding citrus diseases and their vectors. Furthermore, rootstocks screening is required in every single agro-ecological zones where citrus is grown for the simultaneous management of citrus viroids, viruses, and soil-born fungi.