Observation on black dead arm in French vineyards

Transcription

1 Phytopthol. Mediterr. (2001) 40, Supplement, S336 S342 Oservtion on lck ded rm in French vineyrds PHILIPPE LARIGNON, RÉMY FULCHIC, LAURENT CERE nd BERNADETTE DUBOS INRA, Centre de Recherches de Bordeux, UMR en Snté Végétle INRA/ENITA, BP 81, Villenve d Ornon cedex, Frnce Summry. Blck ded rm ws first identified in French vineyrds in It produces symptoms in the vine wood, cusing decline nd eventully deth. Previously, this disese ws confused with esc ecuse of the similrity of the folir symptoms. Two forms of lck ded rm, mild nd severe form, were oserved in French vineyrds on Cernet Suvignon nd Suvignon. Isoltions from 23 vines collected from four vineyrds locted in three viticulturl districts of Bordeux showed tht the min fungi ssocited with the rown streks were Botryospheri otus, B. dothide nd Trichoderm spp. Pthogenicity tests showed tht B. otus nd B. dothide cused drk lesions on 1- yer-old cnes. Therefore, these two fungi merit further study to determine their role in cusing lck ded rm. Key words: grpevine, Botryospheri otus, Botryospheri dothide. Introduction Blck ded rm is cryptogmic disese tht ws descried for the first time in 1974 from Hungrin vineyrds (Lehoczky, 1974), nd lter from Itly in the provinces of Iserni (Cristinzio, 1978) nd Reggio-Emili (Rovesti nd Montermini, 1987). The disese produces symptoms in the wood of the plnt, cusing decline nd eventully deth. The term lck ded rm ws introduced y Lehoczky (1974) to distinguish the disese he oserved from the ded rm disese cused y Phomopsis viticol Scc. The cuse ws ttriuted to Botryospheri stevensii Shoem. (nmorph Diplodi mutil Fr. pud Mont.) in Hungrin vineyrds (Lehoczky, 1974), nd to Botryospheri otus (Schwein.) Shoem. [nmorph Spheropsis mlo- Corresponding uthor: P. Lrignon Fx: E-mil: lrignon@ordeux.inr.fr rum (Berk.) Berk.] in Itlin vineyrds (Cristinzio, 1978; Rovesti nd Montermini, 1987). Recently, this disese ws identified for the first time in Frnce, in Bordeux vineyrd (Lrignon et l., 2000). In the pst, the disese ws confused with esc ecuse of the similrity of the folir symptoms. Annul losses in Bordeux vineyrds from lck ded rm re estimted to e from 4 to 20%. In the Bordeux re, ffected vines over 8- yers-old strted to show symptoms y the end of My. Symptoms first ppered on the leves t the se of the shoots nd then spred to the other leves, continuing to pper throughout the growing seson. Two forms of the disese were oserved: severe form nd mild form, leding in ech cse to premture lef fll. The severe form (Fig. 1) ws chrcterized y dieck of one or more shoots, ccompnied y lef drop, shrivelling nd drying of inflorescences or fruit clusters. Frequently, few leves remined clinging to the shoot tip (Fig. 1). S336 Phytopthologi Mediterrne

2 Blck ded rm in French vineyrds Sometimes, new growth occurred from xillry uds in the proximl portion of the shoot. In severe cses disesed shoots died entirely. The mild form ws chrcterized y wine-red (red cultivrs) or yellowish-ornge (white cultivrs) spots on the mrgins of the leves or on the lef lde, which colesced to form lrge zones of deteriortion etween the veins nd the mrgins of the lef (Fig. 2 nd 3). Inflorescences or fruit clusters my wither. Leves tht did not drop showed vrious ptterns of necrosis which hve een recently descried y Lrignon nd Duos (2001). In the wood, this disese ws chrcterized y rown strek 1 2 cm wide under the rk which egn t the se of the ffected shoot nd extended upwrd to the grft union (Fig. 4). The rown strek is delimited y yellowish-ornge order few millimeters in depth, in which the vessels re occluded. This disese differed from esc in numer of chrcteristics. Thus, symptoms of lck ded rm ppered erlier in the seson (end of My) thn those of esc (end of June). Leves of vines with lck ded rm never showed yellow spots. On red vrieties, the red pigmenttion ws drker thn tht of esc. Brown streking of the wood under the rk ws oserved only in lck ded rm. The purpose of this study ws to identify the fungi ssocited with lck ded rm in Bordeux vineyrds nd to determine their pthogenicity. Mterils nd methods Plnt mteril nd fungl isoltion Twenty-three disesed grpevines of vrious cultivrs were collected in 1998 nd 2000 from four vineyrds locted in three viticulturl districts of Bordeux. Seven vines were collected t Medoc 1 from one plot ech of Cernet Suvignon, Cernet Frnc nd Merlot. At Medoc 2, seven vines were smpled from plot of Cernet Suvignon nd one of Suvignon; t Entre-Deux-Mers, five vines from plot of Cernet Suvignon, nd t Suternes, four vines from plot of Suvignon. The vines rnged in ge from 8 35 yers nd ll hd the folir symptoms of lck ded rm oth (mild nd severe form). Isoltions were mde from rown streks in the wood of the trunks s descried y Lrignon nd Duos (1997). The fungi found were identified nd the numer of rown streks infected with ech fungus ws recorded. Any Botryospheri species isolted were identified with reference to Shoemker (1964), Lehoczky (1974), Phillips nd Lucs (1997), nd Punithlingm nd Wller (1973). Pthogenicity tests Ten isoltes of Botryospheri otus nd three isoltes of Botryospheri dothide (Moug. : Fr) Ces. nd De Not. were isolted from disesed vines collected in 1998 nd They cme from four of the vines previously mentioned (isoltes mrked with n sterisk in Tle 1) nd other vines from French regions (Tle 1). The ility of isoltes of B. otus nd B. dothide to produce rown streks ws determined y inoculting them onto 1-yer-old cnes (10 cm long) of Cernet Suvignon in the lortory. A hole 5 mm in dimeter ws drilled to the pith nd filled with 5-mm dimeter plug cut from the growing edge of 2-dy-old colonies on mlt extrct gr. Control cnes were filled with uncolonized mlt extrct gr disks. Filled holes were seled with Prfilm. Twenty cnes were inoculted with ech isolte of B. otus nd incuted for 21 dys t 25 C in the drk. After this time, the rk ws removed from the prt of the cne round the hole nd the length of ny rown streks ws mesured. Ten cnes were inoculted with ech isolte of B. dothide, incuted for 7 dys under the sme conditions s descried ove, nd exmined for lesions s with B. otus. At the end of the experiment, pieces of tissue from symptomtic wood were trnsferred to pltes of mlt extrct gr to test for Botryospheri. The experiment ws repeted once. Dt were nlyzed using the STATISTICA progrm (SttSoft, Tuls, OK, USA) nd the mens of lesion lengths were compred using the Newmn- Keuls test fter nlysis of vrince (Snedecor nd Cochrn, 1957). Results Fungl isoltion The fungi most frequently isolted from the rown streks were Botryospheri otus, B. Vol. 40, Supplement, 2001 S337

3 P. Lrignon et l. Fig. 1. Symptoms of the severe form of lck ded rm on Cernet Suvignon. ) Dieck of shoots. ) After premture lef fll, few leves remin clinging to the vine. Tle 1. Sources of Botryospheri otus nd Botryospheri dothide used for pthogenicity tests. Botryospheri species Isolte code Geogrphic origin Source Cultivr B. otus F98-1 Perpignn SD (wood) Syrh F99-4* Medoc BDA (pycnidi) Merlot F99-7 Die YGD (wood) Clirette F00-7 Chmpgne BDA (strek) Pinot Meunier F00-14 Chmpgne BDA (strek) Pinot Meunier PC R51 P178 Grves BDA (pycnidi) C. Suvignon c LVLC R8 P54* Medoc BDA (pycnidi) C. Suvignon LL R12 P84* Medoc BDA (pycnidi) C. Suvignon NJP R2 P75 Entre-2-Mers BDA (pycnidi) C. Suvignon NJP R5P5* Entre-2-Mers BDA (pycnidi) C. Suvignon B. dothide Bd 1 Medoc Berry Merlot Bd 3 Chmpgne BDA(strek) Chrdonny Bd 3-3 Medoc BDA (wood) C. Suvignon Isoltes re from the collection of Unité Mixte de l Recherche en Snté Végétle, INRA Bordeux, Frnce, except from (*) which were otined from four vines exmined during this study. BDA: Blck Ded Arm, SD: Syrh Decline, YGD: Young Grpevine Decline (1). c C. Suvignon, Cernet Suvignon. (1) At the generl Assemly of the 2nd ICGTD meeting held in Lison 2001 it ws unnimously decided tht the disese will henceforth e clled Petri disese. S338 Phytopthologi Mediterrne

4 Blck ded rm in French vineyrds Fig. 2. Left nd right, folir symptoms of the mild form of lck ded rm on Cernet Suvignon. Fig. 3. Folir symptoms of the mild form of lck ded rm on Suvignon. Fig. 4. Symptom in the wood. Peeling off the rk showing rown strek. Vol. 40, Supplement, 2001 S339

5 P. Lrignon et l. dothide nd Trichoderm sp. (Tle 2) which were isolted from 69.6, 34.8 nd 39.1% of ll vines respectively. Others fungi, isolted t lower frequencies, were Alternri sp., Aspergillus sp., Botryospheri stevensii, Epicoccum sp., Ppulri sp., Penicillium sp., Pestloti sp. nd Verticillium cephlosporium (Tle 2). The frequency of ech fungl species isolted vried ccording to site. At Entre-Deux-Mers, B. otus ws the only species found nd t Medoc 1 it ws the dominnt species, lthough Trichoderm nd Aspergillus species were here lso isolted. At Medoc 2 nd Suternes, oth B. otus nd B. dothide occurred with species from severl oth- Tle 2. Fungi ssocited with lck ded rm symptoms in vines tken from four different vineyrds in the Bordeux region of Frnce. Fungl species Vineyrd Entre-Deux-Mers Medoc 1 Medoc 2 Suternes Totl Botryospheri otus Botryospheri dothide Trichoderm spp Botryospheri stevensii Aspergillus spp Penicillium spp Pestloti sp Verticillium cephlosporium Ppulri sp Epicoccum sp Alternri sp Numer of vines exmined The dt re the numer of plnts with the rown strek from which the fungi were isolted. Tle 3. Pthogenicity of Botryospheri otus on 1- yer-old cnes of Cernet Suvignon. Isolte code Men lesion length (mm) Virulence group Control 0.63 ± F ± NJP R2 P ± PC R51 P ± LL R12 P c ± NJP R5P c ± F c ± LVLC R8 P cd ± F d ± F d ± F d ± Dt re mens of forty replictes per tretment ± SD. Mens in the sme column followed y the sme letter re not significntly different (P=0.05) ccording to the Newmn- Keuls test. er fungl gener, nd here B. dothide ws dominnt. Trichoderm species occurred only in the two Medoc vineyrds. Pthogenicity tests Isoltes of B. otus cused drk strek in 1- yer-old cnes (Tle 3) nd were re-isolted from ll lesions. There were significnt differences in the men lesion lengths cused y the vrious isoltes. Four distinct virulence groups were distinguished. Isoltes F98-1, F99-7, F00-14, LVLC R8P54 formed significntly longer lesions fter 21 dys thn did the other isoltes. Isoltes F99-7 nd NJP R2P75 cused the smllest necroses, which were similr in length to those of controls. Isoltes of B. dothide cused drk streks on 1-yer-old cnes fter 7 dys (Tle 4) nd were re-isolted from ll lesions. There were no significnt differences in the lengths of lesions produced y the three isoltes of B. dothide. No Botry- S340 Phytopthologi Mediterrne

6 Blck ded rm in French vineyrds ospheri species were isolted from the controls. A few differences were oserved etween the symptoms of lck ded rm in the wood (nturl infection) nd the lesions on the cnes cused y rtificil inocultion with the two Botryospheri spp. Lesions on the cnes were drker thn the rown streks oserved in stnding vines. Moreover, the yellowish-ornge zones which delimited the rown streks were not oserved on the cnes rtificilly infected with Botryospheri. Discussion Tle 4. Pthogenicity of Botryospheri dothide on 1- yer-old cnes of Cernet Suvignon. Isolte code Men lesion length (mm) Virulence group Control 0.8 ± Bd ± Bd ± Bd ± Dt re mens of twenty replictes per tretment ± SD. Mens in the sme column followed y the sme letter re not significntly different (P=0.05) ccording to the Newmn- Keuls test. The microiologicl exmintion of the 23 disesed vines suggested tht two fungi were minly ssocited with lck ded rm in the Bordeux region, nmely, B. otus nd B. dothide. Pthogenicity tests showed tht B. otus produced drk lesions on one-yer-old cnes. These results re in greement with those of Cristinzio (1978), nd Rovesti nd Montermini (1987), who considered B. otus pthogen of grpevines in Itly. However, vrious uthors consider this fungus sprophyte (Lrignon nd Duos, 1997) or secondry pthogen (Phillips, 1998). Lrignon nd Duos (1997) frequently found it in ssocition with Eutyp lt nd Fomitipori punctt where it ws considered secondry fungus in the process leding to the wood degrdtion chrcteristic of esc (Lrignon, 1991). Phillips (1998) showed tht it ws wekly pthogenic on grpevine. Its frequent ssocition with Phomopsis viticol nd B. dothide suggested tht it my e secondry pthogen. These differences could e due to differences in virulence mong pthogen strins since in our pthogenicity tests, two of the isoltes were not pthogenic. Concerning B. dothide, our study showed tht this fungus my lso e involved in lck ded rm. These results corrote those of Phillips (1998) who showed tht B. dothide cused drk lesions on 1- yer-old vine cnes. He lso reported it s pthogen of grpevine in Portugl where it ws ssocited with excoriose nd dieck of grpevines. Prdel Filho et l. (1995) lso reported it s cusing trunk cnker of grpevines in Brzil. Furthermore, it is well documented s pthogen of other lignicolous plnts such s thornless lckerry (Ms, 1984), pistchio (Michilides, 1991), lmond (English et l., 1975) nd pech (Wever, 1974). Of the remining fungi isolted from the streks, only B. stevensii hs een reported to e pthogenic on grpevine, cusing lck ded rm of grpevines in Hungry (Lehoczky, 1974). The other fungi re most likely sprophytic on the tissues killed y the prsites. Trichoderm spp., often isolted from rown streks, re known to e ntgonistic to mny fungi (Duos, 1987). The dt presented in this pper show tht two fungi re ssocited with lck ded rm in the Bordeux re. However, the symptoms of lck ded rm on the wood were not reproduced exctly when these fungi were inoculted on the cut cnes. This is proly due to the fct tht the tests were not done on stnding vines. Inocultions into stnding vines nd reproduction of folir symptoms would e necessry to determine the involvement of these fungi in the disese. Acknowledgements This work ws supported y grnts from the Conseil Interprofessionnel des Vins de Bordeux, Frnce. Literture cited Cristinzio G., Grvi ttcchi di Botryospheri otus su vite in provinci di Iserni. Informtore fitoptologico 28(6), Duos B Fungl ntgonism in eril iocenoses. In: Innovtives Approches to Plnt Disese Control, (I. Chet ed.) Wiley & Sons Pul., New York, NY, USA, English H., J.R. Dvis nd J.E. De Vy, Reltionship of Botryospheri dothide nd Hendersonul toruloide to cnker disese of lmond. Phytopthology 65, Lrignon P., Contriution à l identifiction et u mode Vol. 40, Supplement, 2001 S341

7 P. Lrignon et l. d ction des chmpignons ssociés u syndrome de l Esc de l vigne. PhD Thesis, University of Bordeux II, Bordeux, Frnce. Lrignon P. nd B. Duos, Fungi ssocited with esc disese in grpevine. Europen Journl of Plnt Pthology 103, Lrignon P. nd B. Duos, Le Blck Ded Arm. Mldie nouvelle à ne ps confondre vec l esc. Phytom 538, Lrignon P., P. Lecomte nd B. Duos, Comment évluer l importnce des mldies du ois dns le vignole? Union Girondine 956, Lehoczky J., Blck Ded-rm disese of grpevine cused y Botryospheri stevensii infection. Act Phytopthologic Acdemie Scientirum Hungrice 9, Ms, J.L., Botryospheri dothide cne cnker of thornless lckerry. Plnt Disese 68, Michilides T.J., Pthogenicity, distriution, sources of inoculum, nd infection courts of Botryospheri dothide on pistchio. Phytopthology 81, Prdel Filho O., I.J.A. Rieiro nd H. Kuniyuki, Podrido do tronco d videir (Vitis vinifer) cusd por Dothiorell sp., form nmórfic de Botryospheri dothide. Summ Phytopthologi 21, Phillips A.J.L., Botryospheri dothide nd other fungi ssocited with excoriose nd dieck of grpevines in Portugl. Journl of Phytopthology 146, Phillips A.J.L. nd M.T. Lucs, The txonomic sttus of Mcrophom flccid nd Mcrophom reniformis nd their reltionship to Botryospheri dothide. Sydowi 49, Punithlingm E. nd J.M. Wller, Botryospheri otus. CMI Descriptions of Pthogenic Fungi nd Bcteri 394. Rovesti L. nd A. Montermini, Un deperimento dell vite custo d Spheropsis mlorum diffuso in provinci di Reggio Emili. Informtore Fitoptologico 37(1), Shoemker R.A., Conidil sttes of some Botryospheri species on Vitis nd Quercus. Cndin Journl of Botny 42, Snedecor G.W. nd W.G. Cochrn, Méthodes sttistiques. Iow Stte University Press, USA, 649 pp. Wever D.J., A gummosis disese of pech trees cused y Botryospheri dothide. Phytopthology 64, Accepted for puliction: Novemer 12, 2001 S342 Phytopthologi Mediterrne