Banana bunchy top virus (BBTV) is a plant virus of the genus Babuvirus, family Nanonviridae affecting Musa spp. (including banana, abaca, plantain and ornamental bananas) and Ensete spp. in the family Musaceae.[106] Banana bunchy top disease (BBTD) symptoms include dark green streaks of variable length in leaf veins, midribs and petioles. Leaves become short and stunted as the disease progresses, becoming 'bunched' at the apex of the plant. Infected plants may produce no fruit or the bunch may not emerge from the pseudostem.[107] The virus is transmitted by the banana aphid Pentalonia nigronervosa and is widespread in SE Asia, Asia, the Philippines, Taiwan, Oceania and parts of Africa. There is no cure for BBTD, but it can be effectively controlled by the eradication of diseased plants and the use of virus-free planting material.[108] No resistant cultivars have been found, but varietal differences in susceptibility have been reported. The commercially important Cavendish subgroup is severely affected.