Differentiation of Begomoviruses and Bemisia tabaci biotypes using
Transcription
Differentiation of Begomoviruses and Bemisia tabaci biotypes using
Differentiation of Begomoviruses infecting tomato crops and Bemisia tabaci biotypes using real time PCR Lambros C. Papayiannis1 and Nicolaos I. Katis2 Agricultural Research Institute, Nicosia, Cyprus 2 Aristotle University of Thessaloniki, Greece 1 Tomato yellow leaf curl disease (TYLCD) TYLCD is one of the most devastating viral diseases of tomato, causing severe damage and heavy losses in many tropical and subtropical regions of the world EPPO 2005 Symptomatology on tomato plants Young plants 9 Severe stunting 9 Bushy appearance 9 Small, puckered and distorted leaves 9 Downwards leaf curling 9 Interveinal chlorosis 9 Usually produce unmarketable fruits Symptomatology on tomato plants Older plants 9 Abnormal growth above point of infection 9 Some flowers may fall or fail to set fruits TYLCD Host Range Cultivated plants Phaseolous vulgaris >100 Weed plants Capsicum annuum Causal agents of TYLCD 9 Several virus species have been shown to be the causal agents of the disease worldwide, all assigned in the genus Begomovirus of the family Geminiviridae 9 EPPO region: two main species and two recombinants Tomato yellow leaf curl virus (TYLCV)- also known as Israel type Tomato yellow leaf curl Sardinia virus (TYLCSV)- Sardinia type Tomato yellow leaf curl Malaga virus (TYLCMaV) Tomato yellow leaf curl Axarquia virus (TYLCAxV) Bemisia tabaci Genadius 9 The whitefly vector Bemisia tabaci transmits Begomovirus species in a persistent, circulative manner 9 First reported in 1889 by Gennadios infesting tobacco (Aleurodes tabaci) 1980 – today Has spread around the globe, infesting vegetable, ornamental, fiber crops and many other arable and weed plants 1160 different species of whiteflies have been identified so far and B. tabaci is considered to be among the most important ones 9 9 9 9 9 Polyphagous – colonizes > 600 Eudicots High reproductive capacity (11-15 generations per year) Adapts and spreads very easy High genetic polymorphism - Biotypes Insectiside resistance ¾ Direct damages – feeding activity ¾ Indirect damages –Transmission >100 plant viruses Detection methods of Begomoviruses involved in TYLCD • Serology • Molecular Hybridization • Loop Mediated Isothermal Amplification • Polymerase chain reaction (specific primers, RFLP, SSCP) • qPCR assay for quantitation of TYLCSV Detection methods currently used for identification of Bemisia tabaci biotypes • Polymerase chain reaction – RFLP, RAPD • Sequencing analysis of mtCOI gene • Microsatellite analysis AIM OF THIS STUDY ¾ Development and validation of primers and probes for the detection and differentiation of viruses and vectors involved in Tomato yellow leaf curl disease epidemics using Real-Time TaqMan PCR technology ¾ Identify the incidence and prevalence of Begomoviruses and Bemisia tabaci biotypes in Greece and Cyprus Materials and Methods Probe TYLCV TAQ PRIMER TYLCV R PRIMER TYLCV F PRIMER TYLCSV F Probe TYLCSV TAQ PRIMER TYLCSV R Materials and Methods 9 Begomovirus Isolates 9 DNA extraction 9 Polymerase chain reaction (PCR): TY(+)/TY(-) primers followed by RFLP analysis – AvaII (Accotto et al. 2001) – EPPO Protocol 9 Multiplex PCR primers AC1048/AV632/AC950 (Martinez-Culebras et al. 2001) 9 Results were compared to the Real Time PCR assay Materials and Methods ¾ B. tabaci samples were collected from Greece, Cyprus, Israel, Spain, Italy, Mexico, USA DNA was extracted from females Charge Switch® magnetic bead technology Partial amplification and sequencing analysis cytochrome oxidase I gene (Frohlich et al., 1999) of mitochondrial Partial amplification and RFLP analysis of mitochondrial cytochrome oxidase I gene (Bosco et al., 2003) Materials and Methods Primers and Probes were designed for Real Time TaqMan PCR tests BIOTYPE Q BTQ-F: AATGCCTCGCCGATATTCAG BTQ-R: AATCCTTCCCGCAGAAGAAATT BTQ-T: TexasRed-TTATGCTGATTGTTATCTAGTATGGAACA-BHQ BIOTYPE B BTB-F: GGTATTTGGAAGGTTGGGTATAATTTAT BTB-R: ACTGTGAATATATGATGACCTCAAACAA BTB-T: FAM-CTATATTGACTATTGGTATTCTAGGGTTT-BHQ Results Identification of TYLCV and TYLCSV using reported protocols TYLCV II) Multiplex PCR TYLCV/TYLCSV TYLCV-Sar Λακωνία TYLCV-Isr Κύπρος RFLP (Ava 302 ζβ 360 ζβ TYLCSV-Sardinia 150 ζβ TYLCV-Isr 277 ζβ TYLCSV 68 ζβ 1 2 3 4 5 6 7 1 2 3 4 5 6 7 8 9 10 11 12 Multiplex detection of TYLCV/TYLCSV with Real-Time TaqMan PCR TYLCSV TYLCV PCR-RFLP results from B. tabaci samples Bemisia tabaci Biotype Β Bemisia tabaci Biotype Q Multiplex detection of B and Q biotypes B. tabaci with Real-Time TaqMan PCR Q-like biotypes Cyprus Greece Israel Spain USA B biotypes Α-Biotype T.vaporariorum Papayiannis et al., 2009 Bulletin of Entomological Research Summary ¾ A real time PCR assay was developed for multiplex detection and differentiation of Begomoviruses involved in TYLCD ¾ The assay is extremely sensitive (>100 times from conventional PCR), specific and suitable for typing large numbers of field crops and weeds ¾ A TaqMan PCR assay for rapid discrimination of Bemisia tabaci biotypes B and Q was also developed and evaluated for several whitefly individuals from different geographical regions ¾ Both assays were successfully used in a large scale survey for identification of the virus species and vectors involved in TYLCD in Greece and Cyprus Summary ¾ In Greece both TYLCV and TYLCSV coexist ¾ In Cyprus TYLCV is the only Begomovirus related to TYLCD ¾ In Cyprus B. tabaci biotype B and possibly Q are involved to TYLCD ¾ In Greece biotype Q is the predominant type. B biotype is reported for the first time in Rhodes island ¾Other B. tabaci -transmitted viruses are found in countries neighboring EU and new strategies for managing the whiteflyvirus complex should be developed and adopted Acknowledgements 9 Prof. J.K.Brown, University of Arizona 9 All those who have supplied Begomovirus-infected material and whitefly samples for our studies Dr L. Tomassoli (Istituto Sperimentale per la Patologia Vegetale, Rome, Italy), Dr. J. Morris (Central Science laboratory, York, UK), Prof. Gutierrez and A. Alvaro-Fernandez (Instituto Agrofestal DelMediterraneao, Valencia, Spain), Prof. A. M. Idris (University of Arizona), Dr G. Anfoka (Faculty of Agricultural Technology, Al-Balqa’ Applied University, Jordan), Mr. A. Paraskevopoulos (Directorate of Agriculture, Kyparissia, Greece), Dr. Horowitz, Israel 9 Cyprus Research Promotion Foundation for funding this study Thank you!