Variation in Nectria radicicola and its anamorph, Cylindrocarpon destructans

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Mycol. &S. 94 (4): 433-442 (l990) Printed in GTta/ Bri/ain

Variation in Neciria radicicola and its anamorph, Cylindroearpon desirucians

GARY J. SAMUELS TIle New York Botanical Garden, Bronx, N.Y. 10458-5126, U.s.A

DA VID BRA YFORD CAB lnlernaiional Mycological lnsutute, Ferry Lane, Kew, Surrey TW9 3AF, England

Variation in Neciria radicicola and its anarnorph, Cylindrocarpon deslrudans. Mycological Research 94 (4): 433-44i (1990).

Neclria radicicola is characterized by ils dislinctive perilhecial morphology and analomy, and by ils anamorph, Cylilldrocarpoll deslruclans, Several collections readily idenlified as N. radicicola were made in New Zealand, Indonesia, and Venezuela. Pure cultures derived from ascospores isolaled from these collections showed considerable variation in cullural and morphological characterislics. The anamorph, Cylindrocarpon desirudans var. desiruclans, is characterized by a fast growth rale and by the formalion of discrele chlamydospores, It is distinguished from C. deslrudans var. coprosmae (C Booth) comb. nov., which has a slower growth rale and does not form discrete chlamydospores. Cylindrocarpon deslrucians var. coprOSlllae is the anamorph of N. radicicola var; coprosmae (Dingley) slat. nov. Cylindrocarpon macroconidialis sp. nov., the anamorph of N. radicicola var. macroconidialis var. nov.. is dislinguished by larger macroconidia. Other varianls of C. desitutluns are discussed bul are not given separate taxonomic slalus because they are based on single collections, Neclria ausiroradicicola sp. nov. is dislinguished from N. radicicoia by having much larger ascospores and by its anarnorph, C. ausirodesirucians sp. nov. Key words : Neclria radicicola, Cylindrocarpon destrudans, Taxonomy.

"Gerlach &. Nilsson (1963) reported perithecia of an unidentified species of Neclria on leaves, peduncles, and bulbs of Cyclamen persicum L. infeded with Cylindrocarpoll radicicola Wollemv. in Sweden. The cultures derived from ascospores isolaled from those perithecia were morphologically consistent with C. radicicola. Gerlach &. Nilsson (1963) described the Neciria as the new species, N. radicicola. Booth (1966) later concluded that the name C. radicicola was antedated by C. desiruclans (Zinnsm.) Scholten. Cylindrocarpon deslructans is a common, soil-borne fungus with a wide distribution (CMI Distribution Map no. 461, 1985). The plant pathology literature contains many records of its involvement in diseases, most often as the cause of seedling blights, basal rots of bulbs and root rots of diverse plants (Gerlach, 1961; Booth, 1967; Domsch et al., 1980). Strains of C. deslructans from different sources and localities show great variation in the morphology of their cultures and conidia. The question therefore arises as to whether more than one taxon can be distinguished. However, since C. deslrucians has relatively few dislindive morphological traits, and those available tend to be plastic, it is difficult to interpret the observed patterns of variation . Further information derived from studies of the holomorph is required in order to allow a reassessment of anamorph characters. 29

Since 1971, 91 specimens have been collected that could be identified as N. radicicola from northern South America, Jamaica, Indonesia, and New Zealand. We were able to isolate ascospores from 41 of those specimens and to study variation among the isolates in culture. The variation observed in Nectria radicicola and its anamorph is the object of the present report.

MATERIALS AND METHODS Single ascospores were isolated with the aid of a micromanipulator onto Cornmeal dextrose agar (CMD, Dileo). Colony descriptions are based on growth on Cornmeal Agar (CMA), Potato Dextrose Agar (PDA) and Potato Sucrose Agar (PSA) (Johnston & Booth, 1983). Although these media have been widely used in plant pathology and in earlier Culindrocarpon studies, we have found that isolates tend to degenerate and produce abnormal spores when maintained on such rich media. Wherever possible, therefore, spore measurements were based on cultures grown on the low nutrient media SNA (Nirenberg, 1976), SNA plus 0'1 % Yeast Extract (Beta Lab) or on Carnation leaf Agar (ClA) (Tio ei al; 1977). These lalter media enhanced macroconidial production and reduced variation in spore shape and size. MYC9t

Variation in Necfria radicicola Growth rates were tested on several media, including PDA, CMA and Czapek-Dox agar. Isolates were grown on SNA for 10 d and then inoculated using a 5 mm cork borer onto 90 mm Petri dishes of the test medium, each containing approx. 20 ern" of agar. Plates were incubated inverted in darkness at 20 0 for 2 d to allow initial growth. Colony diameters were then measured and the plates incubated for a further 5 d before taking the final measurements. Growth rates were calculated as colony extension (mm d- 1). Selected cultures have been deposited in the American Type Culture Collection (ATCC), the CAB International Mycological Institute (CMl) Culture Collection, and the International Collection of Micro-organisms from Plants (ICMP, Plant Diseases Division, DSIR, Auckland, New Zealand). RESULTS

Morphology of Nedria radicicoIa Perithecia of Neciria raditicola are red and occur superficially on woody or herbaceous tissues. They are globose to subglobose, with a broadly conical papilla and a scaly to warted wall. Ascospores are ellipsoid, I-septate, smooth, and colourless. In these characters N. radicicola is not unique, but the perithecial anatomy of the fungus is distinctive. The perithecium is easily seen in whole mounts to possess an outer layer of globose cells 20-30 urn diarn and with thin (1-2 urn) walls. In section, these cells form a definite mantle over the perithecial wall through which the ostiolar region protrudes. Perithecia of N. radicicola are not anatomically similar to any of the other known teleomorphs of Culindrocarpon, which belong to the Necfria mammoidea and N. coccinea groups (SeIlSU Booth, 1959). The only other group of hypocrealean fungi having a similar anatomy of the perithecial wall is that included by Rossman (1983) in Caloneclria de Notaris. On the basis of perithecial anatomy, there is undoubtedly a close relationship between Caloneciria species and N. radicicola. Caloneclria is distinguished from Necfria primarily by its CylilldrocladiulIl Morgan anarnorphs, the shape of the ascospores and asci, and, to a lesser extent, by the fact that the ascospores of most Caloneclria species are multi-septate. Perithecia of N. radicicola are superficially similar to those of N. haemaiococca Berkeley & Broome and N. illudens Berkeley but they are morphologically distinct. Cells at the surface of the perithecial wall of these species are approximately the same large size as those of N. radicicola, but they are angular and tend to have thicker walls. The anamorphs of N. haemaiococca and N. illudens are species of Fusarium sect. Marliella Wollenweber. We do not believe that there is a close relationship between N. radicicola and species of the N. haemaiococca group. Neciria radicicola collections from Jamaica, Venezuela, Indonesia and New Zealand were indistinguishable in the morphological characteristics of their fruit bodies. There was, however, a rather large span of variation in ascospore size, ranging from 6-17 X 2'5-7 11m, the overall mean (±S.D.) being II'6± 1'66 x 4'3 ±0'74 urn (II = 1580). The 400 ascospores measured by Gerlach & Nilsson (1963) from the type

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collection of N. radicicola measured 8-16 x 2'2-4'4 11m and thus included almost the entire range of variation in ascospore size that we have seen in 91 collections from around the world. Although the range of ascospore size within our individual collections was usually narrower than this, in most cases we were unable to correlate different sizes with other morphological features, geographical origin, or substrate. The only exceptions to the homogeneity in our N. radicicola specimens were four New Zealand collections, separated from each other in time and space. These had a perithecial anatomy identical to that of N. radicicola, but possessed consistently larger ascospores than the rest of the collections, having a total range from 17-27 x 6-10 urn and averaging 22'5 ±2'1 x 7'5 ± 1'0 urn. The anamorph produced by these four collections is a Culindrocarpon which may be distinguished from C. desiructans by its larger conidia and different colony characteristics. We introduce the names Neciria ausiroradicicola sp. nov. and Cylilldrocarpoll allStrodesiruclans sp. nov. (for its anamorph) based on these collections.

Variation in unamorph morphology Although the teleomorphs of the fungi discussed here were anatomically and morphologically very similar, there was considerable variation in the cultures obtained from their ascospores. The characteristic colony of N. radicicola is fast growing (30-70 mm diam after 10 d at 20 0 on PDA), brown pigmented, and mycelial or slimy. Cylindrical to ellipsoid microconidia are abundant in fresh isolates. Macroconidia formed in culture are hyaline, (1-) 3 (-5) septate, cylindrical with obtuse apices, straight (rarely curved), and often have a distinct, protuberant, flat, basal abscission scar. Distinct mycelial chlamydospores, either single or in chains or clusters, with thickened, golden-brown walls are abundant in mature cultures. Variations were observed in all of these characteristics, but only occasionally did they form consistent patterns. Two groups of isolates from New Zealand could be distinguished as varieties of N. radicicola. The first group comprised isolates which were slow-growing in culture and did not produce discrete, globose, thick-walled chlamydospures, although swollen, pigmented hyphae were sometimes found. Other colony characters, and conidial morphology fell within the circumscription of 'typical' C. desirucians. These isolates were derived from perithecia formed both on woody and herbaceous substrates and their fruit bodies could not be distinguished morphologically from perithecia that produced colonies typical of C. desiruclans. Neither could they be distinguished from the type collections of N. coproslllae Dingley or N. tawa Dingley. From their type collections, and as described by Dingley (1951), N. coprosmae and N. tawa possess different ascospore sizes. Ascospores in the type specimen of N. coprosmae measure I3'3±1'1 x4'7±0'4 urn (II = 44), whereas ascospores in the type specimen of N. tawa measure II'1 ±0'8 x 3'9±0'4 urn (II = 31). However these measurements are encompassed by the type description of N. radicicola and fall within the range of teleomorphs that gave the C. destructalls-Iike anamorph described above. We conclude that

G. J. Samuels and O. Brayford

N. coprosmae and N. taioa are synonymous but. because of the different anarnorph, they differ from N. radicicola at the varietal level. We therefore describe be low , N. radidcola var. coprosmae var, nov. and its anamorph, C. desfmcfalls var. coprosmae comb. nov. (Figs 3, 4). Booth (1966) attributed Cylilldrocarpoll oblusisporum (Cooke & Harkness) Wollenw. to N. ltuoa. The grounds for this were not discussed, but this was not based on ascospore isolations. Conidia in the type collect ion of C. oblusisporum (K!) arc fusiform and gently curved. Sparse microconidia were found on the host (Acacia sp.). Some anamorphs that belong to N. radicicola can form curved macroconidia, but these remain cylindrical, with obtuse end s, rather than being fusiform and are usually mixed with stra ight spores. We therefore doubt that C. obiusisporum is the anamorph of N. latoa, i.e. N.

radicicola var. coprosmae. The second variant from N. radicicola is based on four collections found in New Zealand on decaying leaves of monocotyledonous plant s. Conidia of these collections formed in culture averaged consistently longer than is usual for C. deslructans (Fig. 6). Conidia formed on natural substrates were longer and had more septa than those formed in culture. Colonies were white to off-white and cottony, with little or no brown pigm entation. Microconidia and chlamydospores w ere not observed. Macroconidia were formed abundantly from scattered con idiogenous cells in the aerial mycelium of these strains whereas, in typical C. desiruclans, microconidia are usually formed in this way. Th is anamorph is therefore distinct from C. desiructans and we propose the name C. maaoconidialis sp. nov. for it. Since the teleornorph is morphologically indistinguishable from N. radicicola, we propose the name N. radicicola var. macroconidialis (Fig . 5). Two collections from New Zealand (POD 34061, POD 34071 (lMI313226» also produced con idia averaging over 40 IJm in length when 3-septate . These specimens were collected on bark of Dacrvocarpus (Podocarpaceae) on the same day and in the same locality. They could be distinguished from the foregoing variety because of the production of abundant microconidia, narrower rnacroconidia and distinctly brown colonial pigmentation. Several C. des/meta/Is strains from other hosts and localities also produced large macroconidia and so further studies are in progress 10 determine their taxonomic status. At present we include them in C. desiruciuns var. des/meta/Is or C. des/meta/Is var. coprosmae, depending upon Iheir growth rate and chlamydospore production. Perithecia of a third variant from New Zealand (POD 41419, IMI313231, GJ5 80-95), collected on a dead flowering

435 stalk of Gahnia sp. (Cyperaceae), contained distinctly spinulose ascospores measuring (8-) 9-11 (-12) x (3'5-) 3'7-4 IJm, be ing at the low end of the range of variation within N. radicicola. Conidiophores formed in fresh cultures from these ascospores were of two types. One type consisted of short, branching clusters of cells formed on the surface of the agar, whereas the second type of conidiophore was up to 150 IJm long and bore a single, terminal penicillus of ampulliform conidiogenous cells and microconidia (Fig. 7). These conidiophores arose from the surface of the agar and from the aerial mycelium. Microconidia were abundant. Most macroconidia had 1-3 septa and were then (13-) 20-34 (-37) x (3'0-) 3'2-4'5 (-5) IJm, tending to be shorter and narrower Ihan in typical C. des/meta/IS. Spores with up 10 9 septa were common in the fresh isolale. Although this collection . differs from typical N. radicicola and C. deslruclans in several charaders of teleomorph and anamorph, because of the plasticity within the N. radlcicola complex, we decline to describe it as a new taxon before additional collections are found. In 1M! there are numerous records of C. des/meta/Is isolaled from plant hosls in New Zealand, Australia, and Tasmania. We have examined cultures ' of typical C. desiruclans from the roots of white clover (Trifolillm repe/IS L.; IMI 313235) and from Phuseolus vlIlgaris L. (lMI 233593) in New Zealand and have isolated it from perithecia found on decaying leaves of Frevcinetia baueriana Endl, subsp. banksii (A. Cunn.) Stone (POD 34052, IMI 313227) and from R/lOpalos/ylis sapida Wend!. & Orude (POD 36654, IMI 313229). Therefore, N. radicicola var, radicicola and its anamorph C. deslrudans appear to be sympatric with its var iants in New Zealand. From the colonies derived from ascospores, a group can be defined within Cylindrocarpon that is centered on C. deslrucians and possesses teleornorphs in the N. radicicola complex. The most distinguishing feature of this group of anamorphs is the ir cylindrical, obtuse, typically straight macroconidia with a protuberant basal abscission scar. Microconidia are usually abundant, but chlamydospores mayor may not be formed, depending on the taxon. Colonies on POA are usually some shade of brown. Several other taxa included in Booth's (1966) monograph of Cylilldrocarpoll are probably allied to the C. deslruciuns group, for example C. didYllll/lll (Harting) Wollenw. and C. desirucians var. emSS1/1Il (Wollenw.) C. Booth. However, none of the isolates from N. radiclcola ascospores studied could be identified as either of these taxa and teleornorphs are not yet known for them. Most isolales known only as anamorphs, often isola led in the context of plant pathological studies, conformed with C. deslruclans var. desirucians.

Key fo discussed iaxa of Nedria and Cylindrocarpon 1. Perlthecla absent 1. Perllh ecia present

2 6 3 4

2. Microconidia rare 10 abse nt 2. M icrocon idia abundant . 3. Colonies on PDA ochraceous, waxy, aerial mycelium lacking ; less Ihan 10 mm diam after 10 d at 20°, barely g rowi ng awa y from C. auslrodeslrucians original inoculum 3. Colon ies on PDA Iuleous , raised, felty with shorl aerial hyphae. 10-20 mm diam after 10 d al 20° . C. nuuroconidialis 4. Colonies on PDA 30-70 mm diarn after 10 d at 20°; d iscrete chlamydospores abundant, single or in chain s or clusters . . ., C. destrudans var. desirucmns 4. Colonies on PDA 5-30 mm diarn after 10 d at 20°; discret e, thick-walled chlamydospores absenl or rare (swollen hyphae may occur) . 5

Variation in Netiria radicicola

436

5. Microconidia formed from long mononematous conidiophores bearing a single terminal penicillus, on Gahnia

.c. d. destrucians (POD 41419, IMI 313231) 5. Microconidia formed from short fasciculate conidiophores on the agar surface, on herbaceous or woody substrates C. desirucians var, coprosmae 6. Ascospores averaging> 20 urn long Neciria ausiroradicicola 7 6. Ascospores averaging < 20 urn long N. radicieola 7. Ascospores (6-) 10-13 (-12) x (2-)3-5 (-7) 11m, smooth; on woody or herbaceous substrates N. d. radicieola (POD 41419) 7. Ascospores (8-)9-II(-I2) x (3'5-)3'7-4 11m. distinctly spinulose; on Gahnia .

DESCRIPTIONS Nedria radicicola Gerlach & Nilsson, Phytopath. Z. 48: 255 (1963) var, radicicola (Figs 1, 2)

Anamorph, Cylindrocarpon destrudans (Zinssm.) Scholten, Neiherl. ]. Plant Path. 70 suppl. (2): 9 (1964). Ramularia desiruclans Zinssm., Phytopathology 8: 570 (1918). Cylindrocarpon radicicola Wollenw., FI/s. auiogr. delin. 2: 651 (1924). Ramularia macrospora Wollenw., Phytopathology 3: 222 (1913), non Fresenius, Beifr. Mykol. 3: 88 (Aug. 1863). Fusarium polvmorphum Marchal, Bull. Soc. Roy. Bot. Belgique 34; 145-148 (1895), non Matruchot, Rech. deoel. Mudd. 84 (1892). Teleomorph, Mycelil/m not visible. Perilhecia solitary to densely gregarious, often seated around the periphery of small cankers; superficial, non-stromatic, easy to remove from the substrate or seated on a minute, inconspicuous basal stroma; broadly pyriform to subglobose, 175-350 urn high x 130-220 urn wide, non-papillate, or with a minute conical papilla; smooth or scaly, becoming laterally pinched or not collapsing when dry; red, not changing colour iry3% KOH, becoming yellow in 100% lactic acid, scales lighter coloured than the rest of the perithecial wall. Cells at the surface of perithecial wall nearly circular in outline, (10-) 20-50 (-60) urn diarn, walls en 1 urn thick. Perithecial wall (20-) 35-50 (-60) urn wide, comprising two distinct regions; outer region 25-30 urn wide, with 2 layers of large cells; inner region of compressed, flattened cells; perithecial apex formed of a palisade of hyphal elements arising from the inner region of the perithecial wall, becoming increasingly more narrow toward the ostiolar canal and merging with the periphyses within. Asci clavate, 40-60 x 7-8 I.Im, apex with a refractive ring. Ascospores ellipsoidal, (6-) 10-13 (-17) x (2-) 3-5 (-7) urn, averaging ll'6±I'66 x 4'3±0'74 urn (II = 1580), equally 2-celled, not constricted at the septum, smooth, colourless, rarely spinulose. partially to completely biseriale, completely filling each ascus,

Anamorph: Colonies grown 10 d at 25°, on PDA 30-70 mm diarn, aerial mycelium floccose, initially white, becoming buff, or sometimes Cinnamon or Hazel (Rayner, 1970); agar becoming strongly pigmented chocolate or chestnut brown below. Degenerated strains often becoming pionnotal or producing tufts of unpigmented, non-sporulating aerial mycelium, or sometimes continuing to sporulate but losing their dark pigmentation. Both micro- and macroconidia normally produced. Conidiopliores arising abundantly from the aerial mycelium and agar surface; aerial 30-70(-100) urn long, unbranched and monophialidic, or irregularly or verticillately branched. or pionnotal

and densely branched, each branch bearing a single, terminal conidiogenous cell. Conidiogenous cells cylindrical or tapering slightly from base to tip, straight, 20-45 x 2-3 urn wide at base x 1'5-2 urn wide at tip. Apex with visible periclinal thickening and ± flared collarette. Microconidia cylindrical, ellipsoid or globose, 4-13 x 4-6 urn, base with a protuberant, flat abscission scar, 0-1 septate, colourless, collecting in slimy colourless droplets at the tip of each phlalide, Macroconidia forming in slimy sporodochia on the agar surface, typically straight, but sometimes curved, cylindrical with obtuse apex and protruding basal abscission scar, colourless, 1-7-septate on host tissues, but mostly 3-septate in fresh isolates in agar culture; often becoming predominantly I-septate in older cultures. Three-septate macroconidia on PSA or SNA (25-) 29'4-36'3 (-46) x (4-) 5-7'5 (-8) urn, Chlamudospores globose, 8-25 urn diarn, discrete, thick-walled, in some strains single and scattered, in others grouped in chains or irregular clusters, becoming golden brown, smooth, forming abundantly in mature colonies.

Habitat: A soil fungus, found on roots of seedling trees and herbaceous plants, also on wood and herbaceous debris. Known disiribuiion, Cosmopolitan. Illustrations: Gerlach & Nilsson (1963: figs 1-7); Booth (1966: fig. 20, anamorph); Booth (1967: figs A, B); Domsch ei al. (1980: fig. 213).

Fig, 1. Cylil1drocarpol1 desiructans (ex neotype). Macroconidia and microconidia.

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G.

J. Samuels

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and D. Brayford

Fig. 2. Cylilldrocarpoll deslruclans var. destructans. Conidiogenous cells, macroconidia, microconidia. and chlamydospores (macroconidia upper left from IMI 313227. macroconidia centre from IMI 313744. curved macroconidia from IMI 312140).

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Specimens examined: Sweden : Bjarred, on dead and rotting bulbs of Cyclamen persicum, Dec. 1961, L. Nilsson (ex type cullure examined GJS 86-511 ex CBS 264--65). U.s.A.. Kentucky: Springfield, on PanaIginseng, Nov . 1922, W. B. Edwards (CUP 11985!. C. destruclans neotype fide Booth, 1966). New Zealand: North Island, Coromandel: litHe Barrier Island, Waipawa Stream, on Rhopnlos/ylissapida, 23 Feb. 1976. Samuels 76-39 (POD 36654, cullure as ICMP 9340, IMI 313229); Thames County. vic. Thames, Coromandel Forest Park. Kauaeranga Valley, on decaying leaf of Freycinelia baueriana subsp.

banksii, 29 Aug. 1974, Dingley. Samuels (74-118) & Haydon (POD 34052; cullure as ICMP 9339. IMI 313227). Taranaki: Mt Egrnont Natl Park. track to Bell's falls from end of Puniho Rd, SE of O kalo, on exposed roots of Coprosma sp., 2 Nov. 1973. Samuels 73-229 (POD 32430; cultures as ICMP 9336. IMI 313225). Wanganu i: Palmerston North, isolated from roots of white dover (Trifolium repens L.). 1983. M. Christensen (anamorph only; culture as ICMP 9448, IMI 313235). South Island, Westland: S. of Hari Hari, Saltwater State Forest (SF 40). on decorticated wood of living Dacryomrpus

Varialion in Neclria radicicola dacrydioides (A. Rich.) De Laubenfels, 2-3 May 1974, Samuels 74-50 (POD 34061 ; culture as ICMP 9338, IMI313226) ; same locality and date, on bark of Dacryocarpus dacrydioides, Samuels 74-56 (POD 34071). Indonesia, North Sulawesi: Eastern Dumoga-Bone National Park. between 'Maddison Camp' (00° 36' N, 123° 50' E) and '1440 Camp' (00° 37' N, 123° 51' E), 980--no m. on cut end of arecoid palm,S Oct. 1985, Samuels 2159 (BO, NY; culture as GIS 85-157, IMI313237), Gn. Poniki, Camp Ice Station Zebra', (00° 26' N, 123° 49' E), 1520 rn, on rachis of tree fern, 17, 18 Oct . 1985, Samuels 2227 (BO, NY), Samuels 2272 (NY), Gn. Muajat, Danau Alia, 00° 45' N, 124° 25' E. 1400 rn, on decaying leaf stalk of Zingiberaceae, 26 Oct. 1985, Samuels 2426 (NY). Venezuela, Merida : ca 63 km W of Merida, La Carbonera, Univ. Los Andes Forest Reserve, on unidentified wood, 20 luI. 1971, Dumont (VE 2512) eI al. (NY, YEN; culture as C. T. Rogerson 71-322, IMI 313222). Yaracuy: In mountains N of Nirgua, on unidentified vine, 7 [ul, 1971, Dumont (VE 1525) eI al. (NY, VEN; cultures as C. T. Rogerson 71-243, 1M! 313223).

Nedria radicicola var. coprosmae (Dingley) Samuels & Brayford, stat. nov. (Figs 3, 4) Neclria coprosntae Dingley, Trans. Roy. Soc. New Zenlmld 79: 200 (1951). Neciria fawa Dingley, Trans. Roy. Soc. New Zealand 79: 199 (1951). Anamorph : Cylindrocarpon destrudans var. coprosmae (c. Booth) Brayford & Samuels, comb. nov. Culindrocarpon coprosmae C. Booth, Myco/. Pap. 104: 16 (1966).

Teleomorph , Periihecia morphologically and anatomically identical to perithecia of N. radidcola var. radicicola bul with distinct anamorph. Asciand ascospores resembling Ihose of N. radicicola var. radicicola, ascospores (8-) 12 (-16) X (3-) 4-5 (-6) urn, averaging 11'3 ± 1'33 x 4'3 ±0'7 urn, Arramorpll : Conidiophores in nature unbranched and monophialidic, fonning in aerial mycelium, or fonning penicillate fascicles on the surface of the substrate, 5D-150 urn long, 4-6 urn wide at the base. Conidiogenous cells cylindrical. 20-75 urn long x 2 urn wide at the tip; apex with periclinal Ihickening and cellarette. Microconidia found in nature oblong to ellipsoidal or cylindrical. 4-16'8 (-26'5) x 2-4'4 (-6) urn, with or without a flat, protuberant basal abscission scar. Macroconidia found in nature cylindrical. straight, with a flat, protuberant basal abscission scar, 1-3-septate; 3-septate macroconidia (24-) 26'3-34'3 (-38) x (5-) 5'5-6'8 (-7) urn. Colonies on PDA reaching 4-10 mm diam after 10 d at 20°; . aerial mycelium sparse 10 floccose, initially white, becoming beige to brown. Pigmenlation of agar variable and dependent upon the slrain; sometimes beige, often tLrk brown. Conidiophores arising abundantly from the aerial mycelium and from Ihe surface of the agar; aerial conidiophores 40-80 urn long, unbranched and monophialidic or once branched, each branch terminating in a single phialide; conidiophores arising from the surface of the colony densely branched and fasciculate, each branch terminating in one to a few conidiogenous cells. Conidiogenous cells cylindrical or tapering slightly from base to tip, straight, (15-) 20-40 (-55) urn long x 3-4 urn wide al base x 2 urn wide al tip; apex with periclinal thickening, cellarette flared or not, Microconidia cylindrical. ellipsoid, or ovoid, 5-15 x 4-6 urn, base with a

438 protuberant flal abscission scar, o-l-seplate, colourless, collecting in slimy colourless droplets at the lip of each phialide. Macroconidia arising in pionnoles from densely branching clusters of conidiophores; phialides from irregularly branching cluslers of cells bearing cylindrical phialides with periclinal thickening and sometimes a flared lip. Macroconidia forming in a layer of slime on the surface of the agar, typically straight, bul somelimes curved, cylindrical with obtuse apex and protruding basal abscission scar, colourless, 1-5-seplale, bul mosl 3-seplale when grown in agar culture. Three-septate conidia on PSA or SNA (25-) 28'3-37'7 (-45) x (4-) 4'7-6'3 (-7'5) urn. Distinct chlamydospores not formed. but in old cultures brown, swollen vegelalive hyphae without thickened walls may occur. Habitat: On many different woody and herbaceous planls including Beilschmiedia (Lauraceae), Coprosma (Rubiaceae), Fuchsia (Onagraceae), Olearia (Asleraceae), Ripogonuin (Smilacaceae), Weillll/n1l11ia (Cunoniaceae), and on the tree fern Cyatllea medullaris (Forsl. f.) Bemh.

Known distribution: New Zealand (North and South Islands). Specimens examined: Holotype. Teleomorph: New Zealand. North Island. Auckland: Waitemata City, Waitakere Ranges. off Anawhata Rd. on COprOSl11il australis (A. Rich.)Robinson, 16 Aug. 1947, Dingley (POD 7472, as Neciria coprosmae). Anamorph: New Zealand. North

Fig, 3, Neciria radicicola var, coprosmae. Median longitudinal section of a mature perithecium, asci and ascospores (left from holotype of N. taioa, righ! from POD 47759).

G. J. Samuels and D. Brayford Fig. 4. Cylindrocarpon destrucians var, coprosmae. Macroconidia and microconidia (from1MI313224 and IMI 130759, curved macroconidia from IMI 313232). Conidiogenous cells as Fig. 2.

439 Fig. s. Neciria radicicola var, macroconidialis (POD 40005). Median longitudinal section of a mature peritheciurn, asci and ascospores.

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Island. Auckland: Whangapona, dried culture ex Coprosma australis, Aug. 1954. Dingley (lMI 70014). New Zealand. North Island. Auckland: Riverhead State Forest along Ararimu Rd. on bark and roots of Coprosma sp.• 2 Aug. 1973, Samue1s-73-152 (POD 31884, culture as IMI 313224); Waitemata City, Waitakere Ranges, Marguerite Track. on Beilschmiedia iaioa (A. Cunn.) Kirk. 21 Mar. 1977, Samuels 77-17 (POD 36655; cultures as ICMP 9341, IMI 313232); Auckland City. Hillsboro, Wattle Bay, on dead flowering stalk of Gahnia sp., 19 Aug. 1980, Samuels (80-95) & Holloway (POD 41419, culture as IMI 313231). Northland : Bay of Islands County, Puketi Forest. vic. Forest Headquarters. Loop Track, on bark of tree. 2 Jun. 1986, Samuels (82-92) & Johnston (POD 44311; cultures as ICMP 9344, IMI313233); Hokianga County, Omahuta State Forest, Ornahuta Kauri Sanctuary, on bark of Olearia sp.. 10 May 1981, Samuels (81-99) & Horak (POD 47917). Auckland : Waitemata City, Tilirangi, on Beilschmiedia tatoa (A. Cunn.) Kirk, May 1948. Dingley (POD 7556, Holotype of Neciria Inwn); Waitakere Ranges, Piha Rd. Cowan Track, on indet. tree, 4 June 1983, Samuels (83-132) & Rossman (POD 46314); Cullygrass Track. on bark and wood of Coptosma nuslralis, 17 Dec. 1974, Dingley, Francis & Samuels (74-138) (POD 34022). Waikato: vic. Te Awamutu. Mt Pirong ia, on Ripogonwn scandens J.R. & G. Forst., Apr. 1985, P. R. Johnston (POD 47759, GJS 85-108). Gisbome; Urewera National Park, Lake Waikaremoana, track to Lake Ruapani, on bark of WeinllulIJnin racel1losn Linn. f.,31 May 1983, Samuels (83-178) el al. (POD 46355); vic. Motor Camp. Tawa Loop Track, on bark, 13 May 1985, Samuels (85-65) & Kohn (POD 47764). South Island. Buller: 22 km SE of Murchison P.O.• on the Murchison-Maruia Saddle Rd, on Fuchsia ezcotlicata O.R. & G. Forst.) Linn. f.• 7 May 1985, Samuels (85-57), Johnston & Kohn (pOD 47766). Westland: N of Hari Hari, Lake Mahinapua Walkway, on bark of indet. tree. 20 May 1983, Samuels (83-155), Malsushima & Rossman (POD 46335; cultures as ICMP 9345, IMI 313240); Mt Aspiring Natl Park. Haast Pass, 30 km E of Haast Junction, Roaring Billy Forest Walk, on bark of Melrosideros sp., 28 Apr. 1985, Samuels (85-39) & Kohn (POD 47767); 23 km E of Haast Junction, along Gap Creek, on bark, 28 Apr. 1985, Samuels (85-33) & Kohn (POD 47765); Westland Natl Park. Franz Josef. track

Fig. 6. Cvlindrocarpon macroconidialis. Conidiophores, conidiogenous cells, macroconidia (conidiophores from IMI 313230, macroconidia from IMI 313230 and IMI 332705).

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440

Fig. 7. Neciria radicicola variant ex Gahnia (POD 41419). Ascus, spinulose ascospores, conidia, conidiophores with terminal penicillus.

to Lake Wombat, on bark, 10 Apr. 1983, Samuels (83-187) & Petersen (POD 46364). Nedria radicicola var. macroconidialis Samuels & Brayford. var. nov. (Figs 5, 6)

Neciriae radicicola var. macroconidiali 79-97. Collection data as teleomorph.

Omnia var. radicicolae Gerlach & Nilsson sed statu anamorphico differt.coloniisin agaro pallidis dein reversis senalis vel cinnamomeis el conidiis (30-) 38-52 (-81) x (4-) 5-7 (-8) 11m. Holotypus: New Zealand. North Island.Waikato: vic. Te Awamulu, Mt Pirongia, track to Mahaukura, on leaves of Collospermum IUlS/Il/lII11 (Col.) Skottsb., 27 Aug. 1979, G.}. & C. Samuels 79-97 (POD 40005, culture ex type as IMI 313230).

Teleomorph: Periihecia identical to those of N. radicicola, 220-280 urn diam. Asci clavate, (42-) 47'9-64 (-80) x (6-) 6'2-7'9 (-9) urn, apex with a refractive ring, s-spored, ascospores partially to completely 2-seriate, completely filling each ascus or a portion of each ascal base empty. Ascospores narrowly ellipsoidal, (9-) 9'6-11'6 (-12) x (2-) 2'7-3'3 (-3'5) urn, equally 2-celled, not constricted at the septum, smooth, colourless.

Status anamorphicus Cylindrocarpon macroconidialis Bray-

Anamorph: Conidiophores in nature arising directly from the

ford & Samuels, sp. nov.

Cylilldrocarpo desiructi similis sed coloniae in agaro pallidae dein reversis senalis vel cinnamomeis et conidiis (30-) 38-52 (-81) x (4-) 5-7(-8) 11m. Holotypus: IMI 313230, culto agaro dessicate. ex ascosporae

surface of the substrate, macronernatous, mononematous, 60-625 long x 2-5 urn wide at tip x 4-7 urn wide at base, unbranched, septate, with a single phialide 65-75 urn long terminating each conidiophore. Conidia cylindrical with tip cell blunt or narrowed, (52-) 62-93 (-IDS) x (5-) 7'9-10'7 (-II),

G. J. Samuels and O. Brayford often with a slightly protuberant, flat basal abscission scar, (4-) 7 (-10)-septate, held in a colourless mass of slime at the tip of each conidiophore. Colonies on POA 50-55 mm diam after 10 d at 20°, with white to buff aerial mycelium, or becoming flat and slimy in appearance. Cultures becoming sienna to cinnamon from below, with pale margin. Conidiophores forming abundantly on small, colourless sporodochia, scattered on the agar surface, and in the aerial mycelium, macronernatous, 40-155 urn long X 1-4 urn wide at tip x 3-5 urn wide at base, unbranched, septate, with a single phialide 38-50 urn long terminating each conidiophore. Macroconidia straight or slightly curved, cylindrical with obtuse ends and often having a protruding basal abscission scar, 3-5 (-7)-septate; 3-septate conidia ranging from (30-) 38-52 (-81) x (4-) 5-7 (-8) urn, Microconidia sparse or absent. Distinct mycelial chlamydospores not observed.

441 Fig. 8. Neciria ausiroradicicola. Section of ascomata (POD 46334), ascus and ascospores.

Habitat: On dead leaves of Asielia, Collospermum and Cordyline. Known distribution: New Zealand (North Island). Additiollal specimens examined: New Zealand. North Island. Taranaki: Inglewood County, Everett Park. on base of dead leaf of Cordvline sp., 1 Oct. 1973, G.J. & C. Samuels 73-216 (POD 32662). Gisbome: Urewera National Park. Lake Waikaremoana, track to Lake Waikariili, on decaying leaves of AsteUa sp., 29 May 1983, Samuels (83-162), Johnston, Malsushima & Rossman (POD 46340, culture as IMI 313234); same collecting data and host, 11 May 1985, Samuels (85-59) & Kohn (POD 47760, ICMP 9349, IMI 332705).

The teleomorph of N. radicicola var. macroconidialis cannot be distinguished morphologically from that of N. radicicola var. radicicola. However, the distinctive anamorph was found . .on all four of the specimens of the large-conidial variety, thus making its identification easy. The dark chestnut brown pigmentation found in cultures of C. desiructans was not observed. Isolate IMI 332705 (POD 47760) formed much larger conidia in culture than did any of the other isolates of this variety, including IMI 313234 (POD 46340) collected in the same locality and on the same substrate but two years earlier. Cylindrocarpon iheobromicola C. Booth may form similarly sized macroconidia but they arise from short, irregularly branching, densely clustered conidiophores rather than tile elongated conidiophores found in C. macroconidialis. Nedria austroradicicola Samuels & Brayford, sp. nov. (Figs 8, 9) Neclriae radicicola similis sed ascosporis (17-) 20'5-24'5 (-27) x (6-) 6'5-8'5 (-10) urn, Holotypus: New Zealand. South Island. Westland: Westland Natl Park. vic. Franz Josef, track to Lake Wombat, on bark of indet. tree, 10 Apr. 1983, Samuels (83-190) and Petersen (POD 46395).

Status anamorphicus Cylindrocarpon austrodestrudans Brayford & Samuels, sp. nov. Fere Cylindrocarpon destrucians sed microconidiis el chlamydosporis in culto agaro nullis ct macroconidiis 3-septatis, (30-)39'2-54'8 (-75) x (5-)5'7-8'3 (-12) urn, Holotypus: ex cuIto agaro dessicato Neclriae ausiroradicicola, Samuels (83-190) & Petersen (POD 46395). Collection data as teleomorph.

Teleomorph: Periihecia morphologically and anatomically identical to N. radicicola var. radicicola, 250-375 urn diam. Asci (65-) 68'3-92 (-105) x (10-) 13'5-18'5 (-20) urn, apex with a minute ring, often appearing simple, (4-) 8-spored. Ascospores broadly ellipsoidal to elliptic-fusiform, (17-) 20'5-24'5 (-27) x (6-) 6'5-8'5.(-10) urn, equally 2-celled, not constricted at the septum, smooth, colourless, biseriale, completely filling the ascus or a small portion of the ascal base empty. Anamorph, Not known from nature. Colonies grown 7-10 d on PDA 7-10 mm diarn, barely spreading away from the inoculum. Aerial mycelium sparse or absent, colonies flat, or sometimes raised and wrinkled, waxy, white at first, becoming pale sienna to ochreous (Rayner 8 to 44) near the centre, similarly coloured from below. Conidiaphores poorly defined, arising abundantly as lateral branches or terminations of hyphae, unbranched or loosely fasciculate, 50-80 urn long x 3-4 urn wide, each branch terminating in a single conidiogenous cell. Conidiogenous cells cylindrical, 17-45 x 3-4 urn, Macroconidia cylindrical, straight, ends obtuse, base round or often with a protuberant, flat, basal abscission scar, 1-6-septate, 3-septate macroconidia (30-) 39'2-54'8 (-75) x (5-) 5'7-8'3 (-12) urn. Microconidia and chlamydospores lacking.

Habitat: On wood, including Fuchsia and Pseudopanax.

442

Variation in Neciria radicicola Fig. 9. Cylilldrocarpoll austrodesiructans. Conidia and conidiogenous cells.

Catlin's State Forest Park, Graham's Rd, Haldane Scenic Reserve, on bark of tree, 17 Apr. 1985, Samuels (85-22), Buchanan & Kohn (POD 47770).

This research was supported in part by grants to GJ5 from the American Philosophical Society, the National Geographic Society (3068-85), and the US National Science Foundation (BSR 8500236). We appreciate the cultures provided to us by Dr Helgard Nirenberg. Dr Rupert C. Barneby (NY) corrected the Latin diagnoses. We also thank Ms G. Butterfill for technical assistance at Clvll. REFERENCES BOOTH, C. (1959). Studies of Pyrenornycetes- IV. Neciria (pad I). Mycological Papers (CM/) 73, I-lIS. BOOTH, C. (1966). The genus Cvlindrocarpon. Mycological Papers (CM!) 104, 1-56. BOOTH, C. (1967). CM.!. Descriptions of Pathogenic Fungi and Bacteria No. 148, Neciria radicicola. DINGLEY, J. M. (1951). The Hypocreales of New Zealand. II. The genus Neclria. Transactions of ilu Royal Society of New Zealand 79, 177-202. DOMSCH, K. H., GAMS, W. & ANDERSON, T.-H. (I 980). Compendium of Soil Fungi 1. New York : Academic Press. GERLACH, W. (1961). Beilrage zur Kennlnis der Gattung Cvlindrocarpon Wr. IV. CylilldrocarpOIl radicicola Wr., seine phytopathologischs Bedeutung und scin Auftreten als Erreger einer Faule des Usambaraveilchens. PltylopillhologiselIe Zeilschri]! 41, 361-369. GERLACH, W. & NILSSON, L. (1963). Beitrage zur Kenntnis der Gattung Cylindrocarpo» Wr. V. Nee/ria radicicola n. sp., die bishcr unbekannte Hauptfruchtfonn von Cvlindrocarpon radicicola Wr. Pl:ylopafhologisclze Zeifschrif/ 48, 25 1-257. JOHNSTON, A. & BOOTH, C. (cd.) (1983). Plant PaflIologist's Pocketbook, 2nd edn. Kew: CAB Internahonal Mycological Institute, NIRENBERG, H. (1976). Untersuchungen uber die morphologische und biologische Differenzierung in der Fusarill/ll-Sektion Liseola.

Mitteilungen ails der Biologischen Bundesansial! fz'ir Land- und ForsfwirisclIaff, Berlin-Dahlem 169, 1-117. RAYNER, R. W. (1970). A Mycological Colour Chart, British Known distribllfioll: New Zealand.

AdditiOllal specimens examined: New Zealand. South Island. Westland: data as holotype, on bark of Fuchsia excorlicala U.R. & G. Forst .) Linn. f., 10 Apr. 1983, Samuels (83-189) & Petersen (POD 46394). North Canterbury : Arthur's Pass Na!1 Park. Cockayne Nature Walk. on bark of Pseudopanax crassijolius (A. Cunn .) C. Koch, 20 May 1983, Samuels (83-154), Matsushima & Rossman (POD 46334). Southland:

(Received for publication 23 M ay 1989)

Mycological Society and CAB Intem allonal Mycological Institute. Kew. ROSSMAN, A. Y. (1983). The phragmosporous species of Neclria and related genera. Mycological Papers (CM!) 150, 1-164. TIO, M., BURGESS, L. W., NELSON, P. E. & TOUSSOUN, T. A. (1977). Techniques for the isolation, culture and preservation of the Fusaria. Australian Plant Pa/hology Sociely Newsleller 6, 11-13.