Transmission of sowbane mosaic virus by Thrips tabaci in the presence and absence of virus‐carrying pollen

Abstract

SummaryWhen pollen of sowbane mosaic sobemovirus (SoMV)‐infected Chenopodium amaranticolor was dusted onto C. amaranticolor and C. quinoa test seedlings which were then infested with 5–10 adult Thrips tabaci, SoMV was transmitted to 25%C. amaranticolor and 88% of C. quinoa plants. Five hours access of T. tabaci to pollen‐contaminated C. quinoa seedlings was sufficient for SoMV transmission, but 1 h was not. SoMV was also transmitted when T. tabaci was mixed with pollen of C. amaranticolor and then placed on C. quinoa test seedlings. Further, plant‐to‐plant transmission of SoMV occurred in the absence of virus‐carrying pollen when T. tabaci was caged on infected non‐flowering C. amaranticolor or C. quinoa for 1–8 days and then adults transferred to C. quinoa test seedlings. This is the first time that thrips have been shown to be a vector of SoMV, and that a virus outside the ilarvirus group is reported to be transmitted using pollen and thrips.

Occurrence and transmission of sowbane mosaic virus in seed from naturally infected plants of spinach (Spinacia oleracea)

“…C. amaranticolor and C. quinoa were good indicator plants for the virus. When testing spinach seeds for infection and determining the persistence of infectivity in expressed sap, we confirmed Hardy and Teakle's (1992) finding that C. amaranticolor is less readily infected than C. quinoa. Systemic symptoms in C. amaranticolor were often star-shaped chlorotic spots highly characteristic of the virus, earlier also descriptively named 'Chenopodium star mottle virus' (Kado, 1966).…”

“…Vector transmission, as possibly by a leafminer fly (Costa et al, 1958), a leafhopper, and a fleahopper (Bennett and Costa, 1961), may be merely mechanical (Costa et al, 1958). Pollen from diseased plants containing the virus (Atriplex coulteri; Bennett and Costa, 1961) or surface contaminated with it (C. quinoa and spinach; Francki and Miles, 1985) can act as a source of infection for mechanical introduction into superficially pollen-polluted plants by rubbing (Francki and Miles, 1985;Hardy and Teakle, 1992) and by Thrips tabaci (Hardy and Teakle, 1992). Information on natural infection by the virus is limited.…”

Life history parameters of Thrips tabaci (Thysanoptera: Thripidae) on six commercial cultivars of canola

“…The empty cells on attacked plants create silvery-white spots, referred to as silver damage, which causes yield reduction. The onion thrips are also an important vector of several plant viruses, such as tomato spotted wilt tospovirus (Kritzman et al 2002;Jenser et al 2003), tobacco streak virus (Sdoodee and Teakle 1987), and sowbane mosaic sobemovirus (Hardy and Teakle 1992). T. tabaci may transmit plant viruses in infested canola plants, but this has not been investigated in Iran.…”

Pathogenicity of three entomopathogenic nematodes against the onion thrips,Thrips tabaciLind. (Thys.; Thripidae)

“…This polyphagous and cosmopolitan pest attacks a wide range of host plants including onion, garlic, cucurbits, potato, leek, bean, eggplant and ornamentals (Capinera 2001) and has high economic importance especially in Iran. Furthermore, it damages indirectly through transmitting some viruses like sowbane mosaic virus and tomato spotted wilt virus (Hardy & Teakle 1992). The current control method for managing T. tabaci on most crop plants is spraying of chemical insecticides but, hidden life habits and short life cycle increase T. tabaci population and necessitate frequent applications of chemical treatments unavoidable (Maniania et al 2003).…”