Briddon, R.W.

Bull, S.E.

Colvin, J.

Maruthi, M.N.

Muniyappa, V.

Greenwich Academic Literature Archive

DISEASE NOTEOCCURRENCE OF BLACK ROT CAUSED BY XANTHOMONAS CAMPESTRIS PV.CAMPESTRIS ON ORNAMENTALKALE IN ITALYR. Buonaurio, F. Santangeli, Moretti C. and C. CagliotiDipartimento di Arboricoltura e Protezione delle Piante, Borgo XX Giugno 74, 06121 Perugia, ItalyIn March 2000, V-shaped yellow lesions were ob-served at the leaf margins of ornamental kale (Brassicaoleracea subsp. acephala) grown as borders in publicgardens in Perugia (Italy). The lesions, only found onbasal leaves, sometimes reached the main leaf vein, andthe veins in the lesions appeared black. From diseasedleaves we consistently isolated smooth, yellow, raisedbacterial colonies on nutrient agar. For pathogenicitytests, ornamental kale plants (cv. Sekito) were water-congested by placing them in clear polyethylene bags 12h before inoculation, then airbrush sprayed with bacter-ial suspensions of six isolates (108 cfu ml-1) and kept in agreenhouse at 18-25°C, at 50-75% relative humidity,with natural lighting. The plants were covered withpolyethylene bags for the first 24 h. About 10 days afterthe inoculation, typical symptoms resembling the natu-ral ones were observed. The bacterium was consistentlyre-isolated from these plants. All the bacterial isolateswere gram-negative, aerobic, catalase-positive, and oxi-dase- and urease-negative. They hydrolyzed esculin, gel-atin, casein and starch, grew at 35°C, produced acidfrom arabinose, glucose, and mannose and producedhydrogen sulfide from cysteine. Based on these bio-chemical, physiological, nutritional and pathogenicitytests, it was concluded that the bacterial isolates fromornamental kale belonged to Xanthomonas campestrispv. campestris (Pammel) Dowson.This appears to be the first report of black rot on or-namental kale, caused by X. campestris pv. campestris, inItaly. The disease was previously described in the U.S.A.(Whipker et al., 1998).Whipker B.E., Gibson J.L., Cloyd R.A., Campbell C.R., JonesR., 1998. Horticulture Information Leaflet 507, New12/98. North Carolina Cooperative Extension Service: 5-9.Corresponding author: R. BuonaurioFax: +39.075.5856482e-mail: buonaurio@unipg.itRecived 19 June 2002Accepted 4 Febraury 2003DISEASE NOTEFIRST REPORT OF ROOT ROTOF LETTUCE CAUSED BYPHYTOPHTHORA CRYPTOGEAIN BELGIUMG. Jamart1 and J. Bakonyi21 Agricultural Research Centre-Ghent, Departmentof Crop Protection, Burg. van Gansberghelaan 96,B-9820 Merelbeke, Belgium2 Plant Protection Institute, Hungarian Academy of Sciences,P.O. Box 102, H-1525 Budapest, HungaryIn January 1998, lettuce plants (Lactuca sativa L. cv.Lollo Bionda) growing in a 0.8 ha hydroponic green-house at Kessel (Belgium) showed severe root and basalstem rot symptoms. Plant growth was reduced, and theincidence of wilted or dead plants was high. Duringpreliminary microscopic examinations, an Oomycetousfungus was observed on the infected tissues. Therefore,surface-disinfected root and stem pieces were placedonto selective P10 medium (Pittis and Colhoun, 1984)to isolate the causal agent. All isolates, recovered fromselective media, developed coenocytic and uneven hy-phae forming white, uniform and fluffy colonies on V8agar medium at 22°C. The cultures produced nonca-ducous, nonpapillate and oval to obpyriform sporangiawith rounded bases in Petri’s solution. Internal prolif-eration of sporangia and hyphal swellings could also beobserved. Chlamydospores and sexual organs were notdetected in solid or liquid cultures. All isolates, theidentity of which was confirmed by H. van Kesteren(Diagnostic Centre of the Plant Protection Service, Wa-geningen, The Netherlands), were identified as Phy-tophthora cryptogea Pethybr. & Lafferty. During an arti-ficial inoculation test a one-week-old agar culture wassubmerged into the nutrient solution of hydroponical-ly-grown two-week-old seedlings cvs. Lollo Bionda andLollo Rosa. Sporangia and zoospores were detected inthe nutrient solution within 1 day, while root and stemdecay, similar to the decay observed on naturally infect-ed plants, appeared within a week; cv. Lollo Biondawas more susceptible than cv. Lollo Rosa. Thepathogen was readily re-isolated from infected tissuesof inoculated plants, but not from non-inoculated con-trols, confirming the pathogenicity. P. cryptogea hasbeen reported as a root pathogen of lettuce in the USA(Linde et al., 1990). It has been detected in hardy orna-mental nursery stocks in Germany (Theman et al.,2002), but this is the first report of P. cryptogea on let-tuce in Belgium and Europe.Linde A.R., Stanghellini M.E., Matheron M.E., 1990. Root rotof hydroponically grown lettuce caused by Phytophthoracryptogea. Plant Disease 74, 1037.Journal of Plant Pathology (2003), 85 (1), 63-65 Edizioni ETS Pisa, 2003 63Pittis J.E., Colhoun J., 1984. Isolation and identification ofPythiaceous fungi from irrigation water and their patho-genicity to Antirrhinum, tomato and Chamaecyparis lawso-niana. Phytopathologische Zeitschrift 110, 301-318.Theman K., Werres S., Lüttmann R., Diener H.A., 2002. Ob-servations of Phytophthora spp. in water recirculation sys-tems in commercial hardy ornamental nursery stock. Euro-pean Journal of Plant Pathology 108, 337-343.Corresponding author: G. JamartFax: +32.9.2722429E-mail: g.jamart@clo.fgov.beReceived 5 December 2002Accepted 8 January 2003DISEASE NOTEFIRST REPORT OF PHYTOPLASMA IN-FECTIONS IN FRUIT TREES AND GRAPEVINE IN ALBANIAA. Myrta1, P. Ermacora2, B. Stamo3 and R. Osler21Istituto Agronomico Mediterraneo,Via Ceglie 9, I-70010 Valenzano (Bari), Italy2Dipartimento di Biologia Applicata alla Difesa delle Piante,Università degli Studi di Udine,Via delle Scienze 208, Udine, Italy3Plant Protection Institute, Durrës, AlbaniaOrchards and vineyards were surveyed in eight dis-tricts of Central and South-Eastern Albania for thepresence of phytoplasma diseases. Symptoms of Euro-pean stone fruit yellows (ESFY), apple proliferation(AP), pear decline (PD), and grapevine yellows (GY)were observed in several plantings. Samples were col-lected for laboratory testing from symptomatic apples(8), pears (4), apricots (3), myrobalans (2), Japaneseplum (1), and grapevines (4). Fruit trees were assayedby single-step PCR using primers f01/r01 specific forthe “AP” phytoplasma group (Lorenz at al., 1995),which comprises AP, PD and ESFY, followed by RFLPusing restriction enzymes SspI e BsaAI. Nested PCR wasused for grapevines using universal primersR16F2/R16R2 (Lee et al., 1995) or P1/P7 (Smart et al.,1996), followed by primers specific for “flavescencedorée” (FD) [R16(V)F1/R16(V)R1, Lee et al., 1995] or“boir noir” (BN) (rStol/fStol, Maixner et al., 1995). Fivefruit-trees (apricot, myrobalan and plum) were infectedby ESFY, five apples by AP and a pear by PD. Allgrapevines had BN, but not FD. The presence of APwas confirmed serologically with a specific monoclonalantibody. Although none of the diseases appeared tospread in epidemic form in Albania, the presence oftheir vectors is suspected since infections were detectedin plants of different varieties and age.Lee I.-M., Bertaccini A., Vibio M., Gundersen D.E., 1995.Detection of multiple phytoplasmas in perennial fruit treeswith decline symptoms in Italy. Phytopathology 85: 728-735.Lorenz K.H., Schneider B., Ahrens U., Seemüller E., 1995.Detection of the apple proliferation and pear decline phy-toplasmas by PCR amplification of ribosomal and nonribo-somal DNA. Phytopathology 85: 771-776.Maixner M., Ahrens U., Seemuller E., 1995. Detection of theGerman grapevine yellows (Vergilbungskrankheit) MLOin grapevine, alternative hosts and a vector by a specificPCR procedure. European Journal of Plant Pathology 101:241-250.Smart C.D., Schneider B., Blomquist C.L., Guerra L.J., Harri-son N.A., Ahrens U., Lorenz K.-H., Seemüller E., Kirk-patrick B.C., 1996. Phytoplasma-specific PCR primersbased on sequences of the 16S-23S rRNA spacer region.Applied and Environmental Microbiology 62 (8): 2988-2993.Corresponding author: A. MyrtaFax: +39.080.4606206 E-mail: myrta@iamb.itReceived 2 December 2002Accepted 13 January 2003DISEASE NOTEPUMPKIN YELLOW VEIN MOSAICVIRUS: A NOVEL BEGOMOVIRUSINFECTING CUCURBITSM.N. Maruthi1, J. Colvin1, R.W. Briddon2, S.E. Bull2and V. Muniyappa31 Natural Resources Institute, University of Greenwich,Chatham Maritime, Kent ME4 4TB, UK2 Department of Disease and Stress Biology, John Innes Centre,Norwich, NR4 7UH, UK3 Department of Plant Pathology, University of AgriculturalSciences, GKVK, Bangalore 560 065, IndiaPumpkin plants (Cucurbita moschata) exhibiting yel-low vein mosaic symptoms were collected in 2001 fromCoimbatore, Tamil Nadu state, South India. TotalDNAs extracted from symptomatic leaves produced di-agnostic PCR-bands using primers designed to amplifythe complete coat protein gene on DNA-A and themovement protein on DNA-B (Muniyappa et al., 2003).Primers were also designed to amplify full-length clonesand sequences of DNA-A (2739 nt) (Genebank No.AY184487) and DNA-B (2683 nt) (AY184488) were ob-tained. Phylogenetic comparisons of DNA-A and -B se-quences of the begomoviruses showed that they weremost closely related to Squash leaf curl China virus(AB027465) at 87% nucleotide identity, and Tomato64 Journal of Plant Pathology (2003), 85 (1), 63-65leaf curl New Delhi virus – Severe isolate (U15015) at56% nucleotide identity. The number and arrangementof viral open reading frames were identical to the OldWorld bipartite begomoviruses. The putative virus wastransmitted by Bemisia tabaci, and has a limited hostrange, infecting four cucurbits and Nicotiana tabacumout of 67 species tested (Muniyappa et al., 2003). Lessthan 90% nucleotide identities in DNA-A allows theconclusion that this is a previously unknown species ofbegomovirus (Fauquet et al., 2000) and we name itPumpkin yellow vein mosaic virus (PYVMV). Fauquet C.M., Maxwell D.P., Gronenborn B., Stanley J.,2000. Revised proposal for naming geminiviruses. Archivesof Virology 145: 1743-1761.Muniyappa V., Maruthi M.N., Babitha C.R., Colvin J., Brid-don R. W., Rangaswamy K.T., 2003. Characterisation ofpumpkin yellow vein mosaic virus. Annals of Applied Biol-ogy 142 (In press).Corresponding author:  M.N. MaruthiFax: +44.1634.883379E-mail: M.N.Maruthi@gre.ac.ukReceived 13 January 2003Accepted 29 January 2003Journal of Plant Pathology (2003), 85 (1), 63-65 65

Pumpkin yellow vein mosaic virus: a novel begomovirus infecting cucurbits

Abstract

Similar works

Full text

Available Versions

Greenwich Academic Literature Archive