First Report of Phaeomoniella chlamydospora on Vitis vinifera, Vitis labrusca, and French American Hybrids in Pennsylvania and New York

Phaeomoniella chlamydospora (W. Gams, Crous, M.J. Wingfield. & L. Mugnai) Crous & Gams (= Phaeoacremonium chlamydosporum) was isolated during the growing seasons of 2001 and 2002 from roots, trunks, and cordons of grapevines including cultivars Concord, Niagara, Steuben, Catawba, Dutchess, DeChaunac, Vidal, Seyval, Chambourcin, Chardonnay, Riesling, Sangiovese, Dolcetto, Baco Noir, Merlot, Villard, Pinot Gris, GR7, and 3309C root stock representing 18 locations in Eastern, Central, and Lake Erie regions of Pennsylvania as well as the Lake Erie and Finger Lakes regions of New York. P. chlamydospora was isolated from 89% of samples from vines 3 to 45 years old showing decline symptoms in the field. Isolates were identified based on a previous description (1) and by internal transcribed spacer (ITS1-5.8S-ITS2) rDNA sequences identical to those of P. chlamydospora isolated from Vitis vinifera from Italy (ex-type culture CBS229.95, GenBank Accession No. AF197973). P. chlamydospora is firmly established as a member of the petri and esca disease complex and as a pathogen of grapevines (2,3). To test pathogenicity of our isolates, approximately 30 μl of a 10⁶ conidia/ml suspension, obtained from six isolates, was injected into the pith of 60 single-node, dormant, unrooted cuttings of '3309C' and 'Concord'. Ten control cuttings of 'Concord' and '3309C' were injected with an equal volume of sterile distilled water. From 24 to 32 weeks after inoculations, all P. chlamydospora-inoculated cuttings exhibited dark streaking of the vascular tissue extending 45 to 50 mm from the point of inoculation. The vascular streaking observed in inoculated plants was identical to symptoms observed in declining vines in the vineyard. Vascular streaking was absent in the controls. P. chlamydospora was isolated as a monoculture from regions of vascular streaking in 89% of inoculated cuttings. P. chlamydospora was not isolated from the water-treated controls. P. chlamydospora is widespread and readily isolated from declining grapevines in Pennsylvania, New York, and other national and international grape growing regions. To our knowledge, this is the first report of P. chlamydospora from the cultivars cited above in Pennsylvania and New York. References: (1) M. Groenewald et al. Mycol. Res. 105:651, 2001. (2) Phytopathol. Mediterr. 39(1), 2000. (3) Phytopathol. Mediterr. 40, Supplement 2001.

Pathological anatomy of needles of Pinus strobus exposed to carbon-filtered air or to three times ambient ozone concentrations, or infected by Canavirgella banfieldii

A necrosis of succulent, elongating, current-year needles of Pinus strobus in the northeastern United States, frequently attributed to "ozone damage," is not due to ozone. The pathological anatomy of affected needles differs from that described for ozone injury and is virtually identical to that described as "semimature-tissue needle blight." The syndrome on affected trees throughout the northeastern United States is consistently associated with the presence of the needlecast fungus, Canavirgella banfieldii. This fungus occurs in the mesophyll of both healthy appearing and dying tissues of such needles before these needles have elongated to half their mature size. The pathological anatomy of infected needles agrees with that described for needlecasts by other researchers, beginning with R. Hartig. In contrast, healthy clones of field-symptomatic and field-asymptomatic trees exposed in open-top chambers to carbon-filtered air and to air adjusted on an hourly basis to 3× ambient ozone concentrations incurred a distinctly different tip necrosis. These necrotic tissues were delimited by an intercellular gummy deposit of unknown composition that appeared to be a type of walling-out response. No hyphae were present in these needles. The pathological anatomy of such needles resembled neither that of the symptomatic parent trees in the field, nor that previously demonstrated in various conifers as due to ozone.Key words: Pinus strobus, Canavirgella banfieldii, needle blight, needlecast, ozone.

Thyronectria balsamea on Abies fraseri in Pennsylvania and North Carolina

In August 1996, several 4- to 6-m-tall Abies fraseri (Pursh) Poir. in Adams County, PA, were found bearing numerous dead branches and/or dead tops. The trees had been severely stressed by being ball-and-burlapped and replanted in 1993. Distinct cankers occurred between the living and dead portions of stems and branches. Associated with these cankers were abundant, reddish-orange, erumpent stroma, each bearing three to 10 similarly colored cupulate ascomata. The latter contained asci bearing two to four large, muriform ascospores that, as they matured, formed large numbers of small ascoconidia, indicating the pathogen was Thyronectria balsamea (Cooke & Peck) Seeler (= Nectria balsamea Cooke & Peck). In September 1996, cankered dead stems and branches from affected A. frasrei Christmas tree plantations in Avery County, NC, were found bearing the same pathogen. This fungus is known on A. bal-samea (L.) Mill. from northern Minnesota east through Canada to northern New York and Newfoundland (2). Funk (1) reported it from A. lasio-carpa (Hook.) Nutt. in (presumably) British Columbia, but gave no details. This is the first report of it in the eastern United States south of northern New York, a considerable extension of its known range, and the first report of it from A. fraseri. Voucher specimens are in PACMA (Pennsylvania State University Mycologica Herbarium, Mont Alto Campus). References: (1) A. Funk. Can. For. Serv. BC-X-222:142, 1981. (2) E. V. Seeler, Jr. J. Arnold Arbor. 21:442, 1940.

Delphinella balsameae Tip Blight of Abies lasiocarpa in Vermont

In 1996, a windbreak planting of Abies concolor (Gordon & Glend.) Lindl. ex Hildebr. and A. lasiocarpa (Hook.) Nutt. on a Christmas tree farm in Lamoille County, VT, incurred tip blight caused by a Delphinella sp. Although only scattered new shoots of the intermixed A. concolor and nearby A. balsamea (L.) Mill. were killed, more than 75% of the new shoots in the lower 1.8 m of the crowns of A. lasiocarpa were killed. This posed the question, whether the pathogen was the native D. balsameae (A. M. Waterman) E. Müller in E. Müller & Arx or whether the western species, D. abietis (Rostr.) E. Müller in E. Müller had been introduced. Dead 1996 shoots were collected from all species on 15 July. Most ascomata were immature. However, occasional ascomata bore well-developed bitunicate asci with hyaline, uniseptate ascospores averaging 40 × 9 μm, confirming the pathogen was D. balsameae (1). Funk reported this pathogen on A. lasiocarpa in British Columbia without documentation; this is the first record of it attacking this species in eastern North Amer-ica. Although the seed source was unknown, the extreme susceptibility of A. lasiocarpa in comparison to other Abies spp. in the area suggests that caution should be used in planting this species in the Northeast. Reference: (1) A. M. Waterman. J. Agric. Res. 70:315, 1943.

Phyllosticta multicorniculata on Abies spp. in the Northeastern U.S

Several needle blight fungi affect natural regeneration and Christmas tree plantations of Abies spp. in northeastern North America. Of these, Phyllosticta multicorniculata Bissett & Palm has been reported from A. balsamea (L.) Mill. in Ontario and Prince Edward Island, and from A. concolor (Gordon & Glend.) Lindl. ex Hildebr. in Wisconsin (1). In Quebec, P. multicorniculata was reported as an endophyte on symptomless needles of A. balsamea (2). In 1994, we collected this fungus in Grafton County, NH, defoliating lower branches of A. balsamea Christmas trees. In July and August 1996, we examined infected A. concolor Christmas trees in Lamoille County, VT. In July, approximately 50% of the 1996 needle complement on the lower 1 m of the crowns was infected and by August the incidence of infection on these branches increased to 75 to 100%. Less severe blighting occurred up to 1.5 m. Dead needles of the 1995 complement bore abundant, mostly empty, pycnidia of P. multicorniculata. The dead and dying distal ends of the 1996 needle complement bore abundant pycnidia of P. multicorniculata in various stages of maturation. This is the first report of this pathogen on Abies spp. in the northeastern U.S. The conidia from actively-sporulating pycnidia bore more numerous and longer appendages (1 to 16, average 7, up to 38 µm long) than the dried herbarium specimens of various ages used in the species description (1 to 5, up to 7 µm long) (1), or similarly reported from culture (2). References: (1) J. Bissett and M. E. Palm. Can. J. Bot. 67:3378, 1989. (2) L. Petrini et al. Sydowia 43:148, 1991.

Canavirgella banfieldii Needlecast of Pinus strobus in Michigan

In the winter of 1995 to 1996, browning and dieback of the 1995 needle complement of Pinus strobus L., resembling needlecast caused by Canavirgella banfieldii Merrill et al. (1), was observed in Antrim County, MI. (Needle dieback = distal portions of the needles die, but short basal segments remain living and diseased needles remain attached until normal shedding of the entire complement.) Affected needles at that time had not developed ascomata, but bore spent pycnidia resembling those of C. banfieldii. About 25% of the symptomatic needles collected on 7 June 1996 bore hysterothecia of C. banfieldii in various stages of development. On wetting about 8% of these opened and released mature ascospores. Voucher specimens are in BPI and PACMA. Heretofore, C. banfieldii has been known from western North Carolina to central New York, northern Vermont, and central and eastern Maine. This is the first report of this pathogen in the Lake States, a significant extension of its known distribution, and substantiates in part our belief that this long-overlooked fungus probably occurs throughout the natural range of P. strobus. Reference: (1) W. Merrill et al. Can. J. Bot. 74:1476, 1996.