Transmission of Spanish Pepper- and Potato-Pvy Isolates by Aphid (Homoptera: Aphididae) Vectors: Epidemiological Implications

Abstract

Transmission of Potato Virus Y (PVY) by several aphid vectors was studied under laboratory and greenhouse conditions to determine vector propensity on sweet pepper ( Capsicum annum L.) plants. Laboratory experiments were conducted with three PVY strains: pepper-PVY pathotype φ (PVY φ ) and potato-PVY (ordinary strain, PVY ∘ , and necrotic-type strain, PVY N ). Pepper ('Yolo Wonder'), tobacco ( Nicotiana tabacum L., 'xhanthi nc'), and potato ( Solanum tuberosum L., 'Bintje') were used as virus sources or test plants, or both. Results showed that both pepper-PVY and potato-PVY strains were transmissible by Myzus persicae Sulzer to pepper plants, although potato-PVY∘ and – PVY N are less efficiently transmitted than PVY ∘ . Transmission tests between different species of aphids using PVY ∘ -infected pepper and tobacco as source plants indicated that M. persicae was the most efficient vector, followed by Aphis gossypii Glover and Acyrthosiphon pisum Harris. Aphis fabae Scopoli also was capable of transmitting PVY ∘ , but with much less efficiency. Greenhouse experiments designed to evaluate the dispersion (secondary spread) of PVY by alatae aphids indicated that M. persicae transmitted the virus at the highest rate. Aphis fabae and Aphis gossypii also were able to spread PVY efficiently under test conditions. Previous works indicated that non-colonizer species, principally in the genus Aphis , have much higher alate activity in open field conditions (higher landing rate) than M. persicae . Therefore, much of the natural spread of virus may be by species that are not commonly found feeding on pepper crops.