Cassava Brown Streak Disease Evidence Note 2022
Published: July, 2022
In Zambia, cassava is the second most important economic staple crop after maize, and a mainstay for an estimated 30% of Zambians. The invasive Cassava Brown Streak Disease, which can cause yield losses of up to 100% in susceptible cassava varieties has emerged as a serious threat with the potential to collapse the cassava subsector in Zambia. The effects of CBSD impacts and management strategies were assessed through a combination of a household survey of 516 households and secondary data. Farmer survey results across the three surveyed districts indicated annual average yield losses of 1.4 t/ha. Early indications of the economic damage due to CBSD in Zambia is estimated to be 55% of total annual cassava production, which corresponds to monetary losses of over US $500,000, annually. CBSD being new in Zambia, management of CBSD symptoms on farmers’ fields include plucking infected leaves, owing to lack of knowledge of effective control or management measures against CBSD. Stringent cross-border sanitary and phytosanitary measures will most likely impede the growth of Zambia’s cassava export market if deliberate remedial actions are not taken as the whitefly vector, Bemisia tabaci that causes CBSD is classified an A2 quarantine pest by the European and Mediterranean Plant Protection Organization and the Caribbean Plant Protection Commission. CBSD is spreading throughout Zambia, underscoring the need to reinforce sanitary and phytosanitary measures, in addition to educating farmers on how to manage the disease.