Abstract:
The causative agent of banana streak disease is Banana streak virus (BSV). In tropical countries, for example Kenya, the virus causes considerable damages to banana crop as well as banana production yields. Several mealy-bug species have been reported as vectors of BSV. However, latent and retention time of the BSV in the oleander mealy-bug (Paracoccus burnerae) are unknown. These characteristics are important in determining the mode of transmission of viruses by their vectors. The purpose of this study was to determine the latent and retention time of the BSV in its vector, P. burnerae. We employed both Immuno-capture Polymerase Chain Reaction (IC-PCR) and Rolling Circle Amplification (RCA) techniques to select diseased and healthy plantlets for transmission trials. RCA assays were performed on the deoxyribonucleic acid samples of viruliferous mealy-bug instars of P. burnerae and on the deoxyribonucleic acid of virus-inoculated plantlets. The findings of the study indicated that BSV has no latent period in P. burnerae during transmission at ambient conditions (9-30°C). However, the vector can retain and transmit BSV for a period of four days under ambient temperatures (9-30°). The results revealed that vector P. burnerae, transmit BSV semi-persistently which is an indication of non-circulative mode of transmission of viruses. The results of this study contribute immensely to the elucidation of the mode of transmission of Banana streak virus by P. burnerae, thus enhancing development of novel control strategies of BSV transmission.
