Virus Research 166 (2012) 13–22 Contents lists available at SciVerse ScienceDirect Virus Research jo u r n al hom epa ge: www.elsevier.com/locate/virusres Molecular characterisation of dicot-infecting mastreviruses from Australia James Hadfield a , John E. Thomas b , Mark W. Schwinghamer c , Simona Kraberger a , Daisy Stainton a , Anisha Dayaram a , Judith N. Parry d , Daniel Pande e , Darren P. Martin f , Arvind Varsani a,g,h,∗ a School of Biological Sciences, University of Canterbury, Ilam, Christchurch 8140, New Zealand b The University of Queensland, Centre for Plant Science, Queensland Alliance for Agriculture and Food Innovation, Ecosciences Precinct, PO Box 46, Brisbane, QLD 4001, Australia c Department of Employment, Economic Development and Innovation, 80 Meiers Road, Indooroopilly, Queensland 4068, Australia d NSW Department of Primary Industries, Tamworth Agricultural Institute, 4 Marsden Park Road, Calala, NSW 2340, Australia e Department of Botany and Horticulture, Maseno University, P.O. Box 333, Maseno, Kenya f Computational Biology Group, Institute of Infectious Diseases and Molecular Medicine, University of Cape Town, Cape Town, South Africa g Electron Microscope Unit, University of Cape Town, Rondebosch, 7701 Cape Town, South Africa h Biomolecular Interaction Centre, University of Canterbury, Ilam, Christchurch 8140, New Zealand a r t i c l e i n f o Article history: Received 21 December 2011 Received in revised form 16 February 2012 Accepted 20 February 2012 Available online 3 March 2012 Keywords: Dicot-infecting mastreviruses Recombination Geminivirus Australia Chickpea Bean Tobacco a b s t r a c t Monocotyledonous and dicotyledonous plant infecting mastreviruses threaten various agricultural sys- tems throughout Africa, Eurasia and Australasia. In Australia three distinct mastrevirus species are known to infect dicotyledonous hosts such as chickpea, bean and tobacco. Amongst 34 new “dicot-infecting” mastrevirus full genome sequences obtained from these hosts we discovered one new species, four new strains, and various variants of previously described mastrevirus species. Besides providing additional support for the hypothesis that evolutionary processes operating during dicot-infecting mastrevirus evolution (such as patterns of pervasive homologous and non-homologous recombination, and strong purifying selection acting on all genes) have mostly mirrored those found in their monocot-infecting counterparts, we find that the Australian dicot-infecting viruses display patterns of phylogeographic clustering reminiscent of those displayed by monocot infecting mastrevirus species such as Panicum streak virus and Maize streak virus. © 2012 Elsevier B.V. All rights reserved. 1. Introduction In Australia chickpea (Cicer arietinum) and bean (Phaseolus vul- garis) are important crops worth more than AUD 250 million a year (Anonymous, 2011a,b). Amongst the most important biotic threats to Australian bean and chickpea cultivation are viruses in the Mastrevirus genus of the family Geminiviridae (Ballantyne et al., 1969; Schwinghamer et al., 2010). Such dicotyledonous-plant infecting mastreviruses also cause major losses in tobacco (Nico- tiana tabacum, family Solanaceae) (Hill and Allan, 1942). Mastreviruses are leafhopper-transmitted, single stranded DNA viruses with 2.5–2.7 kb long circular genomes. The genus contains both species that infect grasses (Poaceae including small grains and maize) and species that infect dicotyledonous plants in Africa, Europe, western and southern-central Asia, and Australia (Brown et al., 2011). Mastreviruses that infect dicots include the recog- nised species Tobacco yellow dwarf virus (TYDV) (Morris et al., 1992) ∗ Corresponding author at: School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand. Tel.: +64 3 366 7001x4667; fax: +64 3 364 2590. E-mail address: arvind.varsani@canterbury.ac.nz (A. Varsani). from Australia and Bean yellow dwarf virus (BeYDV) (Liu et al., 1999) from southern Africa and Pakistan and proposed species chickpea chlorosis virus (CpCV-A, CpCV-B) and chickpea redleaf virus (CpRLV) from Australia (Thomas et al., 2010). Other tenta- tive species such as chickpea chlorotic dwarf virus (CpCDV) from northern Africa and the Indian subcontinent (Horn et al., 1993), chickpea chlorotic dwarf Pakistan virus (CpCDPKV; Nahid et al., 2008), chickpea chlorotic dwarf Syria virus (CpCDSV; Mumtaz et al., 2011), and chickpea chlorotic dwarf Sudan virus (CpCDSDV; Ali et al., 2004) probably represent strains of a single species. Wherever host ranges have been examined, mastreviruses in this group have been found to be capable of infecting a diverse range of dicotyle- donous plant families (although in many cases the identity of the viruses has not been confirmed at the molecular level; Thomas and Bowyer, 1984; Trebicki et al., 2010). CpCDV infects sugar beet (Beta vulgaris, family Amaranthaceae) naturally in Iran (Farzadfar et al., 2008) and TYDV infects species in at least seven plant families, and occurs naturally in a number of these, including tobacco, bean and chickpea (Thomas and Bowyer, 1984; Trebicki et al., 2010). Infection is lethal in susceptible bean cultivars (Ballantyne et al., 1969; Rybicki and Pietersen, 1999) and early-infected chickpea (Horn et al., 1995) but is more often sub-lethal to symptomless. Sub-lethal but often damaging symptoms in dicotyledonous hosts 0168-1702/$ – see front matter © 2012 Elsevier B.V. All rights reserved. doi:10.1016/j.virusres.2012.02.024