Occurrence and Distribution of Banana Bunchy Top Disease in the Great Lakes Region of Africa

摘要

Banana bunchy top disease (BBJD) was first reported in 1958 in sub-Saharan Africa at the INEAC Yangambi research station in the Democratic Republic of Congo (DR Congo). Cases were reported in 1987 in the Rusizi valley encompassing the borders of Burundi, DR Congo and Rwanda. Since then, no study about BBTD had been carried out in this region. A survey was conducted from September to October, 2008 in three provinces (Bujumbura rural, Cibitoke and Bururi) of Burundi, two districts (Kamanyola and Nyangezi) in South Kivu, DR Congo and the Rusizi district in the Western province of Rwanda A total of 7,830 banana mats, 30 randomly selected per plot, were assessed on 261 farms. A structured questionnaire was used to assess, cultivar diversity, BBTD incidence and severity, presence and occurrence of the aphid vector (Pentalonia nigronervosa Coquerel) and farmers' awareness about BBTD management. Leaf samples were randomly collected on symptomatic plants for further PCR analysis to confirm the disease. PCRresults of samples collected in the three countries confirmed the presence of BBTV. Similar banana varieties are grown across the three countries, indicating the cross-border movement of planting materials which may have influenced disease spread over the past decennia. The regional average of BBTD incidence and aphid occurrence was 25% and 46%, respectively. However, no significant relationship between aphid occurrence and BBTD incidence (R=0.3, P= 0.623) was observed. Among the interviewed farmers, 90% were able to recognize advanced BBTD symptoms; while 95% of farmers were unaware of disease management options and stated that no locally cultivar is resistant to the disease. This pinpoints the need for farmers' awareness raising and that tolerant cultivars should be part of control option packages.