Insect Vector Interactions with Persistently Transmitted Viruses*

Department of Disease and Stress Biology, John Innes Centre, Norwich, NR4 7UH, United Kingdom.
Annual Review of Phytopathology (Impact Factor: 9.62). 10/2008; 46(1):327-59. DOI: 10.1146/annurev.phyto.022508.092135
Source: PubMed


The majority of described plant viruses are transmitted by insects of the Hemipteroid assemblage that includes aphids, whiteflies, leafhoppers, planthoppers, and thrips. In this review we highlight progress made in research on vector interactions of the more than 200 plant viruses that are transmitted by hemipteroid insects beginning a few hours or days after acquisition and for up to the life of the insect, i.e., in a persistent-circulative or persistent-propagative mode. These plant viruses move through the insect vector, from the gut lumen into the hemolymph or other tissues and finally into the salivary glands, from which these viruses are introduced back into the plant host during insect feeding. The movement and/or replication of the viruses in the insect vectors require specific interactions between virus and vector components. Recent investigations have resulted in a better understanding of the replication sites and tissue tropism of several plant viruses that propagate in insect vectors. Furthermore, virus and insect proteins involved in overcoming transmission barriers in the vector have been identified for some virus-vector combinations.

Download full-text


Available from: Anna E Whitfield
  • Source
    • "Tomato spotted wilt virus (TSWV) is one of many tospoviruses transmitted by various thrips species, through a virus–vector interaction that has been the subject of major conferences (Ullman et al. 2007) and reviews (German et al. 1992; Whitfield et al. 2005; Pappu et al. 2009), and was ranked second in a survey of plant virologists , based on its perceived economic and scientific importance (Scholthof et al. 2011). Tospoviruses are persistent–propagative viruses (Hogenhout et al. 2008). Acquisition efficiency of tospoviruses is often positively correlated with virus titres in plants and similarly inoculation efficiency with virus titre in the vector (Okasaki et al. 2011). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Tospoviruses are plant viruses in the genus Bunyaviridae transmitted in a persistent–propagative manner by a range of thrips species and cause disease in wide range of cultivated crops and wild hosts. The viruses in this genus are the only plant-infecting members of the Bunyaviridae. A distinguishing feature, of tospoviruses, from other persistent–propagative plant viruses is that acquisition from infected host plants only occurs by larvae of thrips species. This transmission characteristic is modelled generically as acquisition by juveniles, an invasion threshold is derived, and the dynamics of the system are compared with systems where adults only are involved in acquisition and inoculation. The comparison suggests that in the model disease develops faster and to a greater extent where adults are involved in both acquisition and inoculation. In that case, mobile non-viruliferous adults visit infected plants to acquire virus and in turn visit healthy plants to inoculate virus, whereas acquisition by non-mobile juveniles depends firstly on eggs being laid on an infected plant and then on the virus passaging transstadially from the juvenile to the mobile adult form: other factors being equal, the greater the mobility of vectors the greater the probability of both acquisition and inoculation. Where acquisition is by both juvenile and adult forms of the vector, the derived invasion threshold is simply the sum of the component thresholds for each life stage; however, there may be a fitness cost on combining these characteristics expressed as a trade-off between optimising the life history parameters involved in each acquisition route.
    Full-text · Article · Mar 2015 · Arthropod-Plant Interactions
  • Source
    • "The lack of research on MED is noteworthy because this cryptic species is also invasive and a major pest; although generally competitively inferior to MEAM1, MED is more tolerant of insecticides and has displaced MEAM1 throughout China and other Asian countries (Crowder et al. 2010, Pan et al. 2011). MED and MEAM1 also differ in their relationship to tomato yellow leaf curl virus (TYLCV), a complex of circular, single-stranded DNA plant geminiviruses that infects tomato (Solanum lycopersicum L.) and is transmitted by B. tabaci in a persistent and circulative manner (Hogenhout et al. 2008, Ghanim 2014). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Pathogen-mediated interactions between insect vectors and their host plants can affect herbivore fitness and the epidemiology of plant diseases. While the role of plant quality and defense in mediating these tripartite interactions has been recognized, there are many ecologically and economically important cases where the nature of the interaction has yet to be characterized. The Bemisia tabaci (Gennadius) cryptic species Mediterranean (MED) is an important vector of tomato yellow leaf curl virus (TYLCV), and performs better on virus-infected tomato than on uninfected controls. We assessed the impact of TYLCV infection on plant quality and defense, and the direct impact of TYLCV infection on MED feeding. We found that although TYLCV infection has a minimal direct impact on MED, the virus alters the nutritional content of leaf tissue and phloem sap in a manner beneficial to MED. TYLCV infection also suppresses herbivore-induced production of plant defensive enzymes and callose deposi-tion. The strongly positive net effect on TYLCV on MED is consistent with previously reported patterns of whitefly behavior and performance, and provides a foundation for further exploration of the molecular mechanisms responsible for these effects and the evolutionary processes that shape them.
    Full-text · Article · Feb 2015 · Journal of Economic Entomology
    • "Two members of the cryptic species complex, the putative species Middle East-Asia Minor one (herein MEAM1) and Mediterranean (commonly referred to in the literature as the B and Q biotypes, respectively) are known worldwide as the two most invasive and destructive species of the complex (Perring 2001). Evidence suggests that the invasion of MEAM1 and Mediterranean into many regions of the world has led to epidemics of plant diseases caused by begomoviruses transmitted by B. tabaci (Seal et al. 2006, Hogenhout et al. 2008). Although both MEAM1 and Mediterranean are known for their invasiveness, their biological characteristics are rather different (Wang et al. 2010). "
    [Show abstract] [Hide abstract]
    ABSTRACT: The whitefly, Bemisia tabaci (Gennadius), is a cryptic species complex that attacks >600 different species of plants and transmits several plant viruses causing severe economic losses. Until 2010, the B. tabaci complex comprised 24 distinct putative species. Recently, at least 15 new species have been reported. The objective of this study was to identify B. tabaci species present in bean, melon, and tomato crops in Argentina by applying phylogenetic analyses and pairwise comparison of genetic distances of mitochondrial cytochrome c oxidase subunit I (mtCOI) sequences. The 39 proposed whitefly species were identified with both analyses, and the presence in Argentina of one indigenous species, New World 2 (NW2), and two introduced species, Middle East-Asia Minor one (MEAM1) and Mediterranean, was confirmed. Common bean crop presented the three whitefly species detected, with NW2, MEAM1, and Mediterranean being present all together under field conditions. Also, Mediterranean was the only species identified in tomato, whereas MEAM1 was found in melon. To the best of our knowledge, Mediterranean is a recent invasive species in open-field agriculture in the American continent and in greenhouse tomato in Argentina. Additionally, we provide the first report of MEAM1 in common bean and melon. These findings raise several questions on the future scenario of B. tabaci and the viruses it transmits in Argentina.
    No preview · Article · Jan 2015 · Journal of Economic Entomology
Show more