Virus Research 163 (2012) 229–237 Contents lists available at SciVerse ScienceDirect Virus Research journal homepage: www.elsevier.com/locate/virusres Ageratum conyzoides: A host to a unique begomovirus disease complex in Cameroon Walter N. Leke a,b , Judith K. Brown c , Maaike E. Ligthart b,1 , Naaem Sattar b , Dominic K. Njualem a , Anders Kvarnheden b,∗ a Institute of Agricultural Research for Development (IRAD), Bambui, P.O. Box 80, Bamenda, Cameroon b Department of Plant Biology and Forest Genetics, Uppsala Biocenter SLU, P.O. Box 7080, SE-750 07 Uppsala, Sweden c School of Plant Sciences, The University of Arizona, Tucson, AZ 85721, USA article info Article history: Received 29 June 2011 Received in revised form 27 September 2011 Accepted 29 September 2011 Available online 5 October 2011 Keywords: Alphasatellite Begomovirus Betasatellite Geminivirus Virus ecology abstract Ageratum conyzoides (goat weed) is a widespread uncultivated species in Cameroon that exhibits leaf curl disease (LCD) symptoms suggestive of begomovirus infection. In Asia, different begomovirus–satellite complexes have been identified in A. conyzoides. The objective of this study was to determine the identity of the suspect begomoviruses and their associated satellites in A. conyzoides in Cameroon. The results indicated that all three symptomatic A. conyzoides plants examined were infected with a new bego- movirus species, herein named Ageratum leaf curl Cameroon virus (ALCCMV). The ALCCMV genome sequences shared their highest identity, at 84.3–88.5%, with a group of tomato-infecting begomoviruses from West Africa. In addition, a betasatellite and an alphasatellite were cloned from the same symp- tomatic A. conyzoides plants. The betasatellite sequences shared limited sequence identity at 37% or less with the betasatellite Cotton leaf curl Gezira betasatellite, and the new betasatellite species is herein named Ageratum leaf curl Cameroon betasatellite (ALCCMB). The alphasatellite shared 80% nt identity with Tomato leaf curl Cameroon alphasatellite (ToLCCMA), and the new alphasatellite species is herein named Ageratum leaf curl Cameroon alphasatellite (ALCCMA). In addition, two fragments containing begomovirus–alphasatellite sequences were cloned from sample AGLI4, and they were related to the defecting interfering molecule (Y14167) associated with Ageratum yellow vein virus from Asia. These results suggest that the begomoviral–satellite complexes infecting A. conyzoides in Cameroon may be as complex or more so, to species and strains reported thus far from Asia. © 2011 Elsevier B.V. All rights reserved. 1. Introduction Wild, uncultivated plant species are commonly infected with viruses, and may serve as reservoirs of viruses also pathogenic to cultivated plants (Jones, 2009), and can exert dynamic forces on the ecology of natural systems (Wren et al., 2006). Agera- tum conyzoides (billy goat weed; Asteraceae) is native to the tropical Americas, but it is widely distributed in tropical and sub-tropical regions throughout the world. In Southeast Asia, yellow vein symptoms are commonly observed in A. cony- zoides, which have been associated with a complex consisting of the begomovirus Ageratum yellow vein virus (AYVV), the betasatellite Ageratum yellow vein betasatellite (AYVB) and sev- eral different types of alphasatellite molecules (Briddon and Stanley, 2006; Saunders and Stanley, 1999; Saunders et al., 2001; ∗ Corresponding author. Tel.: +46 18 673337; fax: +46 18 673389. E-mail address: anders.kvarnheden@slu.se (A. Kvarnheden). 1 Current address: Crucell Holland BV, Ypsilon Building, Newtonweg 1, 2333 CP Leiden, The Netherlands. Stanley et al., 1997; Tan et al., 1995). In China and Indonesia, additional begomoviruses and DNA satellites have been iden- tified in A. conyzoides plants showing yellow vein or leaf curl symptoms (Huang and Zhou, 2006; Jiang and Zhou, 2004; Kon et al.,2007; Shibuya et al., 2007; Xie et al., 2010; Xiong et al., 2007). Begomoviruses (genus Begomovirus; family Geminiviridae) can cause considerable damage to cultivated dicotyledonous plants in subtropical–tropical and mild temperate habitats (Brown, 2001; Rojas et al., 2005; Varma and Malathi, 2003). They are transmitted in a circulative, persistent manner by the whitefly Bemisia tabaci sibling species group (Brown, 2007, 2010; Brown et al., 1995) and contain a circular, single-stranded (ss) DNA genome comprising either one (∼2.8 kb) or two components (∼2.6 kb each) (Rojas et al., 2005; Stanley et al., 2005). The single DNA component of monopar- tite begomoviruses contains six open reading frames (ORFs). The coat protein gene (cp or V1) and the V2 ORF are expressed from the viral sense strand, and the rep or C1 ORF, which encodes the Rep- initiator protein, and the C2, C3, and C4 ORFs, which are involved in movement and pathogenicity, are expressed from the comple- mentary strand (Navot et al., 1991; Rojas et al., 2005). 0168-1702/$ – see front matter © 2011 Elsevier B.V. All rights reserved. doi:10.1016/j.virusres.2011.09.039