Abstract
Cross-transmission of bunchy top virus from and to banana (Musa sp.) cv. Lakatan and abacá (Musa textilis Nee) cv. Tinawagan Pula was achieved. Bunchy top virus (BTV) from abacá showed a 10% rate three months post-inoculation when aphid-inoculated to banana, whereas a 30% infection rate was obtained when BTV from banana was transmitted to abacá in the same manner. We also confirmed plant species outside the Musaceae family, namely Alpinia zerumbet (shell ginger), known as “gettou” in Japanese, Colocasia esculenta (satoimo) and Canna indica, were alternate hosts of Banana bunchy top virus (BBTV) isolates from banana in Japan and the Philippines. C. indica was found to be a host of BBTV isolates from Japan and the Philippines in which the latter inoculum source could induce severe bunchy top symptoms at a high incidence (100%). Interestingly, A. zerumbet served for the first time as a silent host of Japanese BBTV isolates with a low detection frequency (2/8) yet was conducive for aphid, Pentalonia nigronervosa, multiplication at a rate comparative to varieties of C. esculenta (satoimo, gabi and taimo). Moreover, C. esculenta (satoimo) was found to be an alternate host of Japanese BBTV isolates (11%) for the first time. These findings partly explain the naturally occurring specificity of BBTV isolates towards cultivated and wild plant species as a component of plant-aphid-virus etiology.
