On the transmissibility of PPV by Myzus varians Davidson (Homoptera: Aphididae) to Clematis vitalba L. (Ranunculaceae)

Sharka is one of the most important diseases of stone fruits in Europe and plum pox virus (PPV) is its causal agent. Nowadays, such disease represents a major constraint for the production of peach fruits in Italy. Moreover, such virus systematically infects several herbaceous plants and more than 20 aphid species are known to be able to transmit the disease. Among them, M. varians has become an increasingly severe pest of peach orchards in Italy; its secondary food plants are Clematis spp. Therefore, we carried out specific experiments to verify the capacity of C. vitalba to host the virus. M. varians have been allowed to feed upon on PPV (serotype M) infected peach plants (GF305) and placed in plants in small glasshouses together with healthy C. vitalba plants thus only the alates could reach the herbaceous plants, reproducing the natural cycle of the peach-clematis aphid. A reverse transcription polymerase chain reaction (RT-PCR) assay was applied to detect the presence of PPV in C. vitalba plants. The obtained results confirm the transmission of PPV from peach to C. vitalba by alates of M. varians. This paper reports also, for the first time, that C. vitalba is a suitable alternative host for PPV-M virus serotype