BBTV is the most serious viruses of all banana viruses and causes a devastating disease called Banana bunch Top Disease.
The earliest symptom of BBTV is a series of dark green lines on the otherwise pale green underside of the leaf petiole where it branches away from the pseudostem. These lines often show a “dot-dash” symptom like Morse code. The best leaf to identify this specific symptom is the second youngest leaf, but at a very early stage of infection, the symptom is indistinct. Also, the second youngest leaf may be high up on a mature plant, necessitating a ladder to check the petioles closely.
Banana bunchy top virus is spread between banana plants by the banana aphid (Pentalonia nigronervosa). It is spread over longer distances by the movement of infected planting material.
In Mozambique The disease was first official reported in June 2016, in a commercial farm located in Guija District and in a small farm in Chokwe District, Gaza Province. After the report of the disease the NPPO of Mozambique together with South African scientists visited the infested plantation where samples from both plantation were collected for diagnostic at DUROI laboratory in South Africa. After confirmation the Mozambique NPPO produced and multiplied 500 copies of leaflets and 100 posters to raise awareness of banana producers about the impact of the disease, trained technicians and extension officers, employees, small holder farmers and households. For management of the disease the affected banana producers with assistance of the Mozambique NPPO are controlling the aphid (vectors) and destroying the infected plants.