Mycol. Res. 101 (6) : 721–732 (1997) 721 Printed in Great Britain Fungi associated with leaf spots of palms in north Queensland, Australia J A N E F R O> H L I CH1, K E V I N D. H Y D E1 A N D D A V I D I. G U E S T2 " Department of Ecology and Biodiversity, The University of Hong Kong, Pokfulam Road, Hong Kong # School of Botany, University of Melbourne, Melbourne, Australia Twenty-six fungi associated with leaf spots of palms in north Queensland have been identified, including 12 ascomycetes, one basidiomycete and 13 deuteromycetes. Eight were identified as species new to science. A new species of Pseudospiropes is described and descriptions of two unnamed species of Glomerella are also given. The fungi of the Australian tropics have been poorly studied both ecologically and taxonomically. The paucity of information is unfortunate, but reflects the overall mycological 9, 10 11 12 Cape Tribulation QLD Daintree 13 31 32 21 Julatten 22 – 27 Kuranda 3 – 8 CAIRNS 35 36 29 MAREEBA 15 Atherton 39 28 1 2 16 17 19, 20 Innisfail 33, 34 Palmerston METHODS AND MATERIALS 37 30 Mission Beach 38 14 Dunk Island 18 50 km Fig. 1. Map of collection sites. situation in Australia (Grgurinovic & Hyde, 1993). These fungi are of great interest, not only in our quest for knowledge, but also because of their potential ability to cause outbreaks of plant disease and their potential to produce novel compounds. With only 5 % of the world’s fungi presently known (Hawksworth, 1991) detailed documentation is highly desirable. This paper reports the results of a study into the biodiversity of fungi associated with leaf diseases of palms in the rainforests and nurseries of north Queensland. The palms, like many tropical plants, are colonized by a rich and diverse mycota, yet surveys of fungi on palms in their natural habitat in Australia were not made until recently. Fro$ hlich & Hyde (1994, 1995 a, b, c) and Hyde & Fro$ hlich (1995) have described some of the pathogenic and saprotrophic fungi associated with palms in Australia. Other studies of Australian palm diseases were based on the ornamental palm industry (Forsberg, 1985, 1987 ; Duff, 1987 ; Reid, 1988). The present study was initiated to record the species distribution of fungi associated with palms in northern Queensland. This information is important to the Northern Australian Quarantine Strategy in its efforts to prevent entry of plant diseases through north Australia (Hyde et al., 1991) and to identify possible threats to Queensland’s ornamental palm industry. Two unnamed species of Glomerella, and a new species of Pseudospiropes, are described. Hinchinbrook Island Diseased palm leaves were collected between February and September 1992 from rainforests, nurseries and gardens in far north Queensland (Fig. 1). Material was returned to the laboratory in ‘ snap-lock ’ plastic bags and examined as soon as possible for associated fungi. Some non-fruiting specimens were incubated for 1–7 d in a moist chamber to promote sporulation. Isolations were made by cutting pieces of tissue from the edge of lesions, surface sterilizing them in 0±5 % aqueous Fungi and leafspots in north Queensland palms sodium hypochlorite for 3 min, and then 96 % alcohol for 30 s, rinsing in three changes of sterile water and blotting dry on sterile filter paper. The leaf fragments were plated onto Potato Dextrose Agar (PDA) incorporating 1 % streptomycin and incubated in normal light at room temperature (22–25 °C) until discrete colonies developed (2–3 d). The fungi were subcultured and sporulation promoted in black light incubators. Specimens of the diseased palms and associated fungi are deposited at BRIP and HKU (M). RESULTS AND DISCUSSION Twenty-six fungi associated with leaf diseases of palms were identified to genus and where possible species level. They 722 included 12 ascomycetes, one basidiomycete and 13 deuteromycetes (Table 1). Eight were identified as species new to science. Three of these are described below and most of the remainder have been described elsewhere (Fro$ hlich & Hyde, 1994, 1995 a, b, c ; Hyde & Fro$ hlich, 1995). An abundance of diseased leaf tissue was found in all hosts and at all collecting sites. Although diseased leaves were collected, it was often impossible to elucidate the cause of the diseases. Yellow orange areas developed frequently on leaves of Calamus, but numerous attempts failed to isolate a pathogen. Similarly no cause for yellow lesions found on leaves of Archontophoenix alexandrae throughout the investigation area was identified. Table 1. Fungi associated with leaf spots of palms in north Queensland Host}s Ascomycetes Apiospora sp. Asteridiella sp. Astrosphaeriella frondicola J. Fro$ hl. & K. D. Hyde Glomerella sp. 1 Glomerella sp. 2 Guignardia candeloflamma J. Fro$ hl. & K. D. Hyde Maculatipalma frondicola J. Fro$ hl. & K. D. Hyde Mycosphaerella palmicola Chaudhury & Rao Oxydothis linospadicis J. Fro$ hl. & K. D. Hyde Oxydothis oraniopsis J. Fro$ hl. & K. D. Hyde Oxydothis parasitica J. Fro$ hl. & K. D. Hyde Pseudomassaria sp. Basidiomycetes Graphiola phoenicis (Moug.) Poit. Deuteromycetes Pestalotiopsis adjusta Ellis & Everh. P. elastica or P. theae P. palmarum (Cooke) Steyaert P. phoenicis (Vize) Y. X. Chen Phomopsis sp. Phomopsis sp. 2 Arthrinium state of Apiospora montagnei Bipolaris sp. Bipolaris incurvata (C. Bernard) Alcorn Pseudospiropes arecacensis J. Fro$ hl., K. D. Hyde & D. Guest Cercospora-like sp. Hyphomycete sp. Pseudoepicoccum cocos (F. L. Stephens) M. B. Ellis Archontophoenix alexandriae (F. Muell.) H. Wendl. & Drude (14) Cocos nucifera L. (13) Calamus sp. (17), Oraniopsis appendiculata (Bailey) Dransf., Irvine & Uhl (21), Laccospadix australasicus H. Wendl. & Drude (29) Areca jugahpunya Dransf. (8) Linospadix palmerianus (Bailey) Burrett (29) Pinanga sp. (32) Archontophoenix alexandriae (24, 29), Laccospadix australasicus (29), Licuala ramsayi (F. Muell.) Domin. (24), Linospadix microcarya (Domin.) Burret (28), Linospadix monostachyos (C. Martius) H. Wendl. (29) and Oraniopsis appendiculata (29) Cocos nucifera (6), (16) ; Cape York Peninsula, Torres Strait Islands Linospadix microcarya (28) Oraniopsis appendiculata (29) & Laccospadix australasicus (29) Licuala ramsayi (17, 23, 24) Oraniopsis appendiculata (29) Phoenix dactylifera L. (26), Cape York Peninsula Cocos nucifera (6) Cocos nucifera (14) Calamus moti Bailey (7) & Cocos nucifera (13, 17) Cocos nucifera (6, 9) Neodypsis decaryi Jumelle (20) Calamus sp. (9) Calamus radicalis H. Wendl. & Drude (34) Arenga australasica (H. Wendl. & Drude) S. T. Blake (14) Chrysalidocarpus lutescens H. Wendl. (6) and Neodypsis sp. (20) Licuala ramsayi (17, 24) Archontophoenix alexandriae (5) Licuala ramsayi (24) Cocos nucifera (6) 1, Babinda, Boulders Nature Reserve ; 2, Cairns, beach along a road near Cairns ; 3, Cairns, Botanic Gardens ; 4, Cairns, Botanic Gardens, Board Walk ; 5, Cairns, Environment Park, Blue Arrow Track ; 6, Cairns, Kamerunga Research Station and Edmonton ; 7, Cairns, Rainforest beside road from Cairns to Mareeba ; 8, Cape Tribulation, Mr G. Fowler’s property ; 9, Cape Tribulation, Rainforest 2 km north of the Cape ; 10, Copperlode Dam National Park ; 11, Cow bay, Mr I. Cunningham’s property ; 12, Curtain Fig Tree, Yungaburra ; 13, Dayman Point ; 14, Dunk Island ; 15, Eubenange Swamp ; 16, Flying Fish Point ; 17, Fresh Water Creek State Forest, Kuranda ; 18, Innisfail, bicentennial Rainforest Arboretum ; 19, Innisfail, Caravan Park ; 20, Julatten, Maria’s Palmatum ; 21, Kuranda, Barron Falls ; 22, Kuranda, Dr K. D. Hyde’s property ; 23, Kuranda, Rosebud Nursery ; 24, Kuranda, Saddle Mountain ; 25, Lake Eachum ; 26, Mareeba, Botanical Gardens ; 27, Mission Beach ; 28, Mossman River Gorge ; 29, Mt Lewis ; 30, Palmerston, K-tree ; 31, Palmerston National Park ; 32, Smithfield, Woodman’s, The Palm Factory ; 33, South Johnstone, Mick’s Nursery ; 34, South Mission Beach, Walking Track ; 35, Yungaburra. Jane Fro$ hlich, K. D. Hyde and D. I. Guest 723 Figs 2–13. Glomerella sp. 1. Fig. 2. Leaf spot. Fig. 3. Section of ascoma. Fig. 4. Peridium. Figs 5–10. Ascospores. Figs 11–13. Asci. Bars : 2, 1 mm ; 3–13, 10 µm. Fungi and leafspots in north Queensland palms The number of leaf spots observed on palms in nurseries was much greater than in the rainforest, perhaps a reflection of the crowded nursery conditions. In natural habitats, one or more leaf spot types tended to dominate each palm species (e.g. Archontophoenix, unidentified yellow lesions, Maculatipalma frondicola, leaf spots). The hosts Licuala ramsayi and Cocos nucifera were usually most heavily infected with several types of leaf disease, while small numbers and few types of leaf spot were found on Oraniopsis. Ascomycetes The ascomycetes were commonly associated with leaf lesions. Nine genera from seven families and six orders were identified. This indicates that a wide range of fungi can utilize palm tissue as a substrate. Nine of the 12 ascomycetes identified were found only at one site and a similar proportion were limited to a single host (Table 1). Guignardia candeloflamma, Mycosphaerella palmicola and Maculatipalma frondicola however, were identified in multiple sites (Table 1). The former two species are widely distributed, also having been collected in Papua New Guinea and Indonesia (Table 1). Maculatipalma frondicola was widely distributed in northern Queensland, with a wide host range. Astrosphaeriella frondicola and Oxydothis oraniopsis were also collected from two or more hosts, including Oraniopsis appendiculata and Laccospadix australasicus at Mt Lewis (Site 33, Fig. 1). Descriptions of two unnamed species of Glomerella are given in this paper. Glomerella sp. 1 (Figs 2–13) Leaf damage at the tip of the leaflet, brown then light-brown to grey with senescence (Fig. 2), roughly circular, 3–12 mm diam., medium brown with thin, dark-brown, concentric growth rings and an irregular dark-brown outline. The most recently affected tissue at the advancing front of the infection is darker-brown and has a thick, yellow, outer border. Ascomata scattered throughout the dead area, ovoid, visible only as a blackened ostiole ; in section 112–155 µm diam., 80–125 µm high, immersed and globose (Fig. 3). Ostiole epiphyllous, eccentric and periphysate. Peridium 10–13 µm thick, composed of 3–4 outer layers of elongate, slightly compressed cells with thick, pigmented walls and 1–3 inner layers of flattened cells with thin, hyaline walls (Fig. 4). Paraphyses 62–107±5¬2±5–4 µm, septate, filamentous and hyaline. Asci 52–75¬7–10 µm (xa ¯ 61±75¬8±06 µm, n ¯ 25), 8-spored, unitunicate, fusiform, pedicellate, with a small, inconspicuous, non-amyloid apical apparatus (Figs 11–13). Ascospores 15–19¬4–5±5 µm (xa ¯ 16±68¬4±77 µm, n ¯ 50), biseriate, ellipsoidal, fusiform–ellipsoidal or navicular with one end tapering slightly more than the other, hyaline, unicellular, guttulate with one or two guttules per cell and with a mucilaginous sheath which is visible with Indian ink (Figs 5–10). Known host : Areca jugahpunya. Material examined : Australia, north Queensland, Cape Tribulation, private palm collection, living leaf of A. jugahpunya, Aug. 1992, J. Fro$ hlich, KDH 1533, BRIP 20419 ; living leaf of A. jugahpunya in 724 the pot next to the holotype, Sep. 1992, Fowler, KDH 1548, BRIP 20414. Glomerella sp. 2 (Figs 14–25) Leaf spots irregular in outline, centred on the midrib where the frond splits into a fishtail (Fig. 14) or running along the leaf margin, 43–61¬13–16 mm, identical from above and below, light brown with an orange border. Ascomata 100–138 µm diam., 125–172±5 µm high, immersed, globose except where deformed by veins in the host tissue (Fig. 15), formed on both leaf surfaces, with a central, periphysate ostiole (Fig. 15). Peridium on sides and base of the ascomata 10–20 µm thick, composed of 3–4 layers of cuboidal to elongate cells with thick, black walls and 1–2 inner layers of flattened cells with thin, hyaline walls (Fig. 16). Peridium at the upper surface lacking outer pigmented layers, composed of several rows of very compressed, thin walled cells. Paraphyses 46–90¬3– 4 µm, septate, hypha-like, filamentous, numerous and tapering distally. Asci 50–63¬10–13 µm (xa ¯ 56±65¬10±76 µm, n ¯ 25), 8-spored, unitunicate, ellipsoidal, sometimes slightly curved, apedicellate, apex truncate, with a small, non-amyloid, ring-shaped, apical apparatus, 1±5–2±5 µm diam. (Figs 16, 23–25). Ascospores 11–18¬5–6±5 µm (xa ¯ 14±11¬5±56 µm, n ¯ 50), biseriate, hyaline, obovoid or reniform, single celled with a large, spreading, irregular sheath, visible only in India ink (Figs 18–22). Known host : Linospadix palmerianus. Material examined : Australia, north Queensland, Julatten, Mount Lewis, on living leaf of L. palmerianus, July 1992, J. Fro$ hlich & C. Waite, KDH 1464, BRIP 20425. Both of these fungi are characteristic of Glomerella, in having immersed, obpyriform to subglobose ascomata with a distinct ostiole, unitunicate asci with a refractive subapical ring and unicellular ascospores. They are excluded from Phyllachora as they lack a characteristic dark clypeus or ‘ tar spot ’ (Hanlin, 1990 ; Cannon, 1991) and Physalospora in which asci are fusoid and ascomata are relatively larger (Hanlin, 1990). The asci and ascospores of Glomerella sp. 1 (Figs 2–13) and Glomerella sp. 2 (Figs 14–25) are readily distinguishable in shape and size (Figs 5–10, 18–22). Glomerella arecae Syd. is the only Glomerella species described from palms and this differs in ascus dimensions and ascospore shape (Sydow, 1931). The type material of this species has been requested and is missing. The size ranges given for G. cingulata (which is the type species of Glomerella) are extremely broad (Arx & Mu$ ller, 1954) and encompass those of most Glomerella species. In the absence of a monographic review of Glomerella it is considered premature formally to name new species. Even so, differences in ascospore and ascus morphology, and in host range, appear sufficient to distinguish our taxa from G. cingulata. They are, therefore, described and illustrated. Basidiomycetes Only one basidiomycete, Graphiola phoenicis, was associated with palm disease in this study. This is the most common cause of ‘ false smut ’, a disease of date palms. The taxonomy of Graphiola spp. has been confused (Fischer, 1921 ; Killian, Jane Fro$ hlich, K. D. Hyde and D. I. Guest 725 Figs 14–25. Glomerella sp. 2. Fig. 14. Leaf spot (marked with ink). Fig. 15. Section of ascoma. Fig. 16. Squash illustrating asci. Fig. 17. Peridium. Figs 18–22. Ascospores. Figs 23–25. Asci. Note the subapical ring in 23 (arrowed). Bars : 14, 1 cm ; 15–25, 10 µm. Fungi and leafspots in north Queensland palms Figs 26–34. Phomopsis sp. Fig. 26. Leaf spot. Figs 27, 28. Sections of ascomata. Figs 29, 32, 34. Squash mount illustrating conidiophores and conidiogenous cells. Figs 30, 31, 33. α- and β-conidia. Bars : 26, 1 mm ; 27–34, 10 µm. 726 Jane Fro$ hlich, K. D. Hyde and D. I. Guest 1924), but the genus is now placed in the Graphiolaceae (Kobayashi, 1952 ; Oberwinkler et al., 1982 ; Cole, 1983). All collections of the Graphiolaceae are parasites of palms. Several other basidiomycetes have also been recorded exclusively from palm. Hyaloria trailii (Berk. & Cooke) G. W. Martin and Hyaloria pilacre A. Møller have been found on palms only in tropical South America and Agaricostilbum is known only from weathered palm spathes and rachides (Oberwinkler et al., 1982). Unlike Graphiola species, these organisms all appear to be saprotrophic. Material examined : Australia, north Queensland, Mareeba, private garden, living leaf of P. dactylifera, July 1992, I. Cunningham (HKU(M)1460). Anamorphic fungi Of the miscellaneous assemblage of imperfect fungi associated with leaf diseases of palms four genera merit discussion : Coelomycetes : Pestalotiopsis De Not., Phomopsis (Sacc.) Buba! k, Hyphomycetes : Bipolaris Shoem. : and Pseudospiropes M. B. Ellis. Coelomycetes 727 Pestalotiopsis phoenicis : Cairns, Kamerunga Research Station, on living leaf of C. nucifera, July 1992, J. Fro$ hlich (BRIP 20430, associated with Pseudoepicoccum cocos : Cape Tribulation, Aug. 1992, J. Fro$ hlich (BRIP 20516) ; Pestalotiopsis adjusta ? : Cairns, Kamerunga Research Station, on living leaf of C. nucifera, July 1992, J. Fro$ hlich (BRIP 20466). Phomopsis sp. (Figs 26–34) A species of Phomopsis was found on living leaves of Calamus at Cape Tribulation. Leaf spots were ellipsoidal, with a thin dark-brown margin, and a thick yellow outer halo (Fig. 3). The α-conidia were 7±5–8±75¬2±5–3 µm (xa ¯ 7±92¬2±71 µm, n ¯ 30), hyaline, fusiform, straight, biguttulate and aseptate (Figs 29, 32, 34) and the β-conidia were 28–36¬1–1±5 µm (xa ¯ 30±04¬1±16 µm, n ¯ 25), hyaline, filiform, straight, eguttulate and aseptate (Figs 30, 31, 33). Eleven Phomopsis species have been described from palms and a synopsis of these fungi is given in Table 2. The β-conidia in our species, are however, much longer than in any of these species (Table 2). Several Phomopsis species have recently been described based mainly on account of their unique hosts (Rao & Yadav, 1985, 1989 ; Sankaran et al., 1987 ; Shivas, 1992). Although this is the first record of a Phomopsis species from Calamus, we feel it would be premature to describe it as a new species, because of the uncertainty of host specificity amongst Phomopsis species. The most frequently isolated genus in this study was Pestalotiopsis. In many cases Pestalotiopsis species grew from the surface-sterilized diseased leaf discs placed on agar. Species of Pestalotiopsis are commonly encountered as endophytes in the tropics (Hyde, personal observations). Pestalotiopsis palmarum was isolated from Cocos nucifera and an unidentified Calamus sp., P. phoenicis from coconut palm in Cairns and Cape Tribulation, and a third Pestalotiopsis sp. from C. nucifera in Cairns. The latter taxon keyed to several possible species ; P. calabae West., P. cryptomeriae Cooke, P. siliquasti Thu$ m., P. adjusta, and P. virgiana Oud. (Guba, 1961). The specimen had similar characters to all of these species, but only P. adjusta has previously been isolated from a palm or Pandanus hosts (Guba, 1961). It is not clear if Pestalotiopsis species develop on palms as primary pathogens. Mordue & Holliday (1971) reported P. palmarum as the cause of disease on many palm genera and Ramanujam (1983) isolated a phytotoxin from cultures of the fungus. The pathogenicity of P. phoenicis was tested in this study by spraying a conidial suspension onto the intact fronds of three young sprouted coconuts. No disease symptoms were observed after 12 wk. This result is consistent with those reported by Brown (1975) who found that the P. palmarum ‘ was not able to infect uninjured coconut seedling leaves ’. Nursery tests carried out in Ecuador also showed that no infection occurred on intact surfaces (Turner, 1981) and the phytotoxin isolated from P. palmarum only caused disease symptoms when placed on pin-pricks on the host frond (Ramanujam, 1983). Brown (1975) found that Pestalotiopsis species were able to colonize leaf spots caused by other fungi and the coconut from which P. phoenicis was isolated in this study had leaf spots associated with at least two other fungi. Hyphomycetes Bipolaris incurvata Pathogenicity tests performed in several Queensland nurseries found B. incurvata the cause of mild to severe lesions when inoculated onto many palm species (Forsberg, 1985). The fungus can kill very young seedlings of highly susceptible species, such as Howeia belmoreana and Chrysalidocarpus lutescens (Forsberg, 1987). The disease is mainly a problem in nurseries because of the unsightliness of lesions rather than the effects on development. Leaf spots characteristic of B. incurvata were common in nurseries visited during this study. Despite the wide host range and pathogenicity of the organism, however, it was not seen on palms in the rainforest. It is known to cause serious infection only in young plants which are either over-crowded, under-fertilized or excessively shaded (Ellis & Holliday, 1972 ; J. Fro$ hlich, personal observations). Despite the obvious symptoms of B. incurvata in many nurseries, and the presence of conidia on the lesions, the organism was isolated only twice. This poor recovery was probably due to frequent fungicide applications in the nurseries. The two isolates of Bipolaris were not identical. The morphology of conidia of isolate KDH 1498 (BRIP 20423) was typical of B. incurvata, but that of KDH 1439 (BRIP 20429) was narrower conidia than usually given in the literature. Dr J. L. Alcorn (pers. comm.) has observed other isolates of this taxon with similar narrow conidia. Both specimens are deposited as B. incurvata. Material examined : Pestalotiopsis palmarum : Australia, north Queensland, Fresh Water Creek State Forest, on living leaf of Calamus sp., Feb 1992, J. Fro$ hlich (HKU(M)996) ; Dayman’s Point, living leaf of C. nucifera, June 1992, J. Fro$ hlich (HKU(M)1354) ; Material examined : Australia, north Queensland, Edmonton, nursery, on living leaf of C. lutescens, K. Halfpapp, July 1992, KDH 1439, BRIP 20429 ; Julatten, Maria’s Palmatum, living leaf of an exotic Neodypsis sp., 1992, J. Fro$ hlich, KDH 1498, BRIP 20423. Fungi and leafspots in north Queensland palms 728 Table 2. Synopsis of Phomopsis species on palms Host P. arecae Syd. & P. Syd., Philipp. J. Sci. C. Bot. 9 : 184, 1914 Phomopsis sp., this paper P. caryotae-urensis Petr. & Cif., Ann. Mycol. 28 : 412. 1930 P. cesati Gonz. Frag., As. Espan4 . Progr. Cienc. Congr. Oporto 6 : 39 (1921) 3 Sphaerella phoenicis Ces., 3 Phoma phoenicis (Ces.) Sacc. P. cocoeX s Petch, Ann. R. Bot. Gard. Peradeniya 7 : 311. 1922 P. elaeidis Punith., Trans. Br. Mycol. Soc. 63 : 229. 1977 P. mindorensis Petr., Sydowia 2 : 369. 1948 P. oenocarpi Bat., J. L. Bezerra & J. E. W. Castro, Anais Congr. Soc. Bot. Bras. 13 : 480. 1962 [1964] P. oenocarpicola Bat. & Garnier, Publ. Inst. Micol. Recife 506 : 184. 1966 P. palmicola (Wint.) Sacc., Ann. Mycol. 13 : 128. 1915, 3 Phoma palmicola Wint. Syll. Fung. 10 : 181. 1892 P. phoenicicola Traverso & Spessa, Bol. Soc. Broteria 25 : 177. 1910 P. pritchardiae (Cooke & Harkn.) Sacc., Syll Fung. 18 : 266. 1906, 3 Phoma pritchardiae Cooke & Harkn. P. pritchardiae (Cooke & Harkn.) Sacc. var. chamaeropina D. Sacc., Mycotheca Italica : 1531. 1905 P. rhapidis Gonz.-Frag., Fungi Horti Matrit : 37. 1917 α-Conidia Areca catechu L., on dead petiole and leaf rachides (Philippines) Calamus sp., associated with leaf spots (Australia) Caryota urens L. on dead sheath (Dominican Republic) Phoenix dactylifera L. on dead spathe (Italy) Cocos nucifera on rotten fruit (Sri Lanka) Elaeidis guineensis Jacq. isolates (Malaysia) Palmae (Ecuador) Jessenia bataua (Mart.) Burrett (as Oenocarpus bataua Mart.) on living leaves (Brazil) Oenocarpus, associated with leaf spots (Brazil) Areca catechu, on dead leaves (Philippines) Phoenix dactylifera, on dry rachis (Portugal) Pritchardia sp., on leaves (U.S.A., California) Rhapis excelsa (Thunb.) A. Henry (as Chamaeropsis excelsa Thunb.) living and dead leaves (Italy) Rhapis flabelliforma L’He! ritier on petiole sheath (Spain) Pseudospiropes arecacensis J. Fro$ hl., K. D. Hyde & D. Guest, sp. nov. (Figs 35–45) Etym. : Referring to the family of the host, Arecaceae. Maculae ellipsoideae, 4–7¬2±5–4 mm. Stromata globula, densa, 25–57±5 µm diam. (xa ¯ 43±5 µm, n ¯ 15), 2–4 conidiophoris praedita. Conidiophorae 100–207±5¬3±75–4±5 µm (xa ¯ 156¬4 µm, n ¯ 15), erectae, atrobrunneae, 6–7 septatae, cicatricibus praeditae. Conidia 25–71¬3±75–6±25 µm (xa ¯ 52¬4±3 µm, n ¯ 25), pallide brunnea, obclavata, laeva, 1–2-septata, obtusa. Leaf spots ellipsoidal, 4–7¬2±5–4 mm, identical from above or below, light to medium brown becoming paler towards the central black fruiting structure, a yellow or light green halo often present, but inconspicuous (Fig. 45). Fruiting hypophyllous. Stromata immersed beneath the cuticle, emerging through the stomata, globular, dense, 25–57±5 µm diam. (xa ¯ 43±5 µm, n ¯ 15) with 2–4 diverging conidiophores (Figs 35, 36). Conidiophores 100–207±5¬3±75–4±5 µm (xa ¯ 156¬4 µm, n ¯ 15), erect, dark-brown, 6–7 septate, unbranched, straight and}or flexuous, conidial scars distinct (Figs 43, 44). Conidia 25–71¬3±75–6±25 µm (xa ¯ 52¬4±3 µm, n ¯ 25), pale brown, obclavate, straight or slightly curved, smooth, 2–7pseudoseptate, slightly constricted at the septa, obtuse at the apex, obconically truncate at the base, with a conspicuously thickened hilum (Figs 37–42). Known host : Licuala ramsayi (F. Muell.) Domin. Material examined : Australia, north Queensland, Kuranda, Saddle β-Conidia 8–10¬2±5 µm 18–24¬1 µm 7±5–8±75¬2±5–3 µm 26–36¬1–1±5 µm 6–9±5¬1±5–2±5 µm 7–12¬1±5 µm 7–8¬2 µm 15¬1 µm 7–9¬2–2±5 µm 18–25¬1 µm 6–8¬2–2±5 µm 18–24¬0±5–1 µm 8–12¬2±5–3±5 µm 5–9¬1±5 µm 7–12¬1±5–2 µm 12–15¬1–1±5 µm 5–7¬1–3 µm 16–20¬0±5–1 µm 8–9¬2±3–3 µm Filiform and curved 8–12¬2–2±5 µm Bacilliform spores present Not seen 14¬3 µm 9–11¬3 µm 15¬1±7 µm 6–9¬1±5–2 µm Filiform spores present Mountain, living leaf of Licuala ramsayi, Feb. 1992, J. Fro$ hlich & K. D. Hyde, KDH 1002, BRIP 20471 (holotypus). Twenty-seven species have been described in Pseudospiropes ; most occur on rotting leaves or bark (Ellis, 1976). P. lotorum Morgan-Jones has been isolated from roots of Lotus corniculatus (Morgan-Jones, 1977) and P. saskatchewanensis B. Sutton occurs on living stems of Lonicera glaucescens (Ellis, 1976). Only two species have been described from living leaves, P. indica A. N. Rai & B. Rai, which is associated with leaf spots of Pongamia pinnata (Rai & Rai, 1995) and P. elaeidis (Steyaert) Deighton, which is associated with leaves and especially seedlings of Elaeis guineensis (Deighton, 1985). P. arecacensis differs from both these species in host, the colour of the conidia, septation, and dimensions (P. arecacensis : Licuala, pale brown, 2–7 pseudoseptate, 25–71¬3±75–6±25 ; P. elaeidis : Elaeis, pale golden brown, 5–12 pseudo( ?)septate, 43–130¬5–8 µm ; P. indica : Pongamia, light olivaceous grey, 1–6 pseudoseptate, 16±5–61±5¬3±5–5 µm). Another genus that should be considered is the monotypic Distocercospora. D. pachyderma N. Pons & B. Sutton produces masses of profusely branched conidiophores and conidiogenous cells, with finely roughened conidiophores, conidiogenous cells and conidia and very pale brown distoseptate conidia (Pons & Sutton, 1988). Conidia of P. arecacensis are, however, smooth-walled and resemble more closely those found in species of Pseudospiropes. Jane Fro$ hlich, K. D. Hyde and D. I. Guest 729 Figs 35–44. Pseudospiropes arecacensis. Figs 35, 36. Sections of stromata with bases of conidiophores. Figs 37–42. Conidia. Figs 43, 44. Conidiophores. Bars, 10 µm. Cercospora and related genera must also be considered as this species may have previously been described in these genera. Cercospora Fres. and Pseudocercospora Speg. are genera which mainly cause necrotic spots, or reproduce without causing definite spots, on leaves, pedicels, stems, fruits and bracts (Chupp, 1953). There are over 2000 Cercospora species, but Chupp (1953) noted that they ‘ are limited remarkably in their host range ’. Nine Cercospora and two Pseudocercospora species have been described from palms, but few of these are convincing Cercospora}Pseudocercospora species (Chupp, 1953). Cercospora acrocomiae is an Exosporium as the conidia are very wide, dark- Fungi and leafspots in north Queensland palms 730 Fig. 45. Pseudospiropses arecacensis. Leaf spot on Licuala. Scale bar ¯ 30 mm. Table 3. Synopsis of Cercospora and Pseudocercospora species on palms Cercospora acrocomiae Stev., Insular Agr. Exp. Sta. Puerto Rico (Rio Pedras). Ann. Rep. 1916–17 : 89. 1917 C. calamicola Henn., Hedwigia 42 : 88. 1903 C, elaeidis Steyaert, Bull. Soc. Bot. Belg. 80 : 35. 1948 Cercospora licualae Syd. & P. Syd., Philipp. J. Sci. C. Bot., 9 : 188 (1914), ¯ C. virens Sacc., Bull. Orto. Bot. Napoli 6 : 62. 1921 (Chupp, 1953) C. palmicola Speg., An. Soc. Cient. Argent. 26 : 72. 1888 Cercospora palmae-amazoniensis Bat. & Cavalc., Anais Congr. Soc. Bot. Bras. 13 : 385. 1962 [1964] C. palmicola Speg. forma stilbacea Moreau, Rev. Mycol. Paris Suppl. Colon. 12 : 37. 1947 C. palmivora (Sacc.) Nann., Atti R. Accad. Fisiocritici Siena X. 2 : 491. 1927 ¯ C. preisii Buba! k, Ann. Mycol. 2 : 400. 1904 C. raphiae Deighton, Trans. Brit. Mycol. Soc. 85 : 741. 1985 Pseudocercospora carpentariae Deighton Trans. Brit. Mycol. Soc. 89 : 403. 1987 Pseudocercospora manuensis Matsush., Matsush. Mycol. Mem. 7 : 63. 1993 P. raphidicola (Tominaga) Goh & W. H. Hsieh, Cercospora and similar fungi from Taiwan : 258. 1990 Host Conidiophores Conidia Comment Acrocomia media O. F. Cook, associated with leaf spots (Puerto Rico) Calamus caryotoides A. Cunn., associated with leaf spots (Australia : north Queensland) Elaeis guineensis, associated with leaf spots (Africa) 30–70¬4–8 µm, dark fuliginous brown 30–120¬5–10 (8–12) µm, cylindroclavate, 3–9 septate, dark fuliginous brown 40–80¬4–8 µm, clavate, 5–7 septate, brown An Exosporium (Chupp, 1953) Licuala spinosa Thunb., Licuala sp., spots on leaves (Philippines) 100–180¬4–4±5 µm, dark brown 125–187¬6–10 µm, acicular to obclavate, 6–9 septate, yellowish brown 75–110¬5–7 µm, obclavate, tapering, 3–5 septate, pale olivaceous Wide conidia for a Cercospora (Chupp, 1953), a Pseudospiropes (Deighton, 1985) Types in poor condition, a Helminthosporium ? (Chupp, 1953) Cocos nucifera, on withering leaves (Paraguay) Palm, on living leaves (Brazil) 40–50¬5–6 µm, smoky brown 50–70¬7–9 µm, obclavate, 5–7 pseudoseptate, smoky olivaceous 40–90¬2±5–7±5 µm, obclavate, 6–9 septate, light-brown A Helminthosporium (Chupp, 1953) Elaeis guineensis, on leaves (French West Africa) Variable in length, 4–7 µm, dark brown 40–90¬9–10 µm, obclavate, 3–9 septate, very pale brown Helminthosporium stilbaceum (Moreau) S. Hughes (Hughes, 1952 a) Phoenix canariensis Hort., P. reclinata Jacq. Phoenix sp., associated with leaf spots (U.S.A., Nebraska, Zimbabwe, Austria, Sierra Leone Raphia farinifera (Gaertn.) Hylander associated with leaf spots (Zimbabwe) Carpentaria acuminata Becc. associated with leaf spots (Australia) 21¬4–5±5 µm, brown to dark brown 64–89¬7±5–10 µm, fusoid clavate, 4–11 septate, brown to dark brown A Stigmina (Hughes, 1952 b) 2–10 per stroma, up to 210 µm long, 6±5 µm wide, dark brown 48–117¬5±5–8 µm, obclavate–cylindric, hyaline, 8–16 septate 40–92¬5–9 µm, long obclavate, moderate brown, 4–10 septate 4–5 µm wide 185–250¬5–7 µm, dark brown 112–150¬4–5 µm, brown Palm, rotting petiole (Peru) Hypophyllous, 10 (–20) per stroma, up to 160 µm long, 5–6±5 µm wide, moderate brown 7–26¬2–3±5 µm, pale brown Rhapis excelsa, associated with leaf spot (Japan, Taiwan) 10 (–20) per stroma, 10–30¬2–4 µm, subhyaline to pale brown coloured and thick-walled (Chupp, 1953). Cercospora calamicola has unusually thick-walled and wide conidia characteristic of Helminthosporium. C. elaeidis also has unusually wide (6–10 µm) conidia for a Cercospora (Chupp, 1953). Deighton (1985) found Characteristic of Helminthosporium (Chupp, 1953) A good Pseudocercospora 16–51¬2–3 µm, cylindric, pale brown, 3–13 septate 30–100¬2–3±5 µm, narrowly obclavate or cylindric to filiform, hyaline, 3–10 indistinct septa that C. elaeidis also differs from other Cercospora species in the positioning of old conidial scars and advised that it would be better placed in Pseudospiropes. C. palmicola and C. palmicola forma stilbacea are considered to belong to Helminthosporium Jane Fro$ hlich, K. D. Hyde and D. I. Guest (Hughes, 1952 a ; Chupp, 1953). C. palmivora has been renamed by Hughes (1952 b) as Stigmina palmivora (Sacc.) S. Hughes and C. licualae from Licuala is a Helminthosporium (Chupp, 1953). Cercospora palmae-amazoniensis, C. raphiae, C. raphidicola, Pseudocercospora carpentariae and P. manuensis have been described post Chupp (1953). The conidium dimensions and hosts of these species, however, differ. In Cercospora palmaeamazoniensis conidia are obclavate, 40–90¬2±5–7±5 µm and light brown (Batista & Cavalcanti, 1964). In C. raphiae the conidia (48–117¬5±5–8 µm) are colourless, 8–16 septate, and the host is Raphia (Deighton, 1985). Hsieh & Goh (1990) have transferred C. raphidicola to Pseudocercospora raphidicola, which also has hyaline conidia (30–100¬2–3±5 µm) and are 3–10 septate. In P. carpentariae conidia (40–92¬5–9 µm) are moderate brown, 4–10 septate and the host is Carpentaria acuminata (Deighton, 1987). In P. manuensis the conidia (16–51¬2–3 µm) are pale brown, 3–13 septate and the host is dead palm material (Matsushima, 1993). Pseudospiropes arecacensis differs from these species in conidia size and morphology and in its Licuala hosts and is therefore described as new. The questionable validity of the other Cercospora species from the Arecaceae prompted Chupp (1953) to write ‘ It would be interesting to know if there is a true species of this fungus on the Palmaceae. ’ There are now several species of Cercospora and related genera recorded on palms (Batista, Bezerra & Castro, 1964 ; Tominaga, 1965 ; Deighton, 1987 ; Hseih & Goh, 1990 : Table 3). Thanks are extended to the Australian Quarantine and Inspection Service and Northern Australian Quarantine Strategy for funding this research. The work was carried out whilst K. D. Hyde worked with the Queensland Department of Primary Industries in Mareeba and J. Fro$ hlich was undertaking an Honours degree at the University of Melbourne under the joint supervision of K. D. Hyde and D. I. Guest. J. L. Alcorn and B. C. Sutton are thanked for identifications of some of the fungi discussed and the former also for his comments on the manuscript. T. K. Goh and E. H. C. McKenzie are also thanked for their comments on the draft manuscript. K. Halfpapp and I. Cunningham are thanked for supplying diseased palm material and we are also grateful to R. Huwer and C. Pearce for providing transport and company during field work. A. Y. P. Lee and H. Leung are thanked for photographic and technical assistance respectively. REFERENCES Arx, J. A. von & Mu$ ller, E. (1954). Die Gattungen der amerosporen Pyrenomyceten. BeitraX ge zur Kryptogamenflora der Schweiz 11(1), 1–434. Batista, A. C., Bezerra, J. L. & Castro, J. E. W. (1964). Sphaeropsidaceae antigos e novos. Anais Congresso Sociedade Botanica Brasil 13, 474–483 (1962). Batista, A. C. & Cavalcanti, W. A. (1962[1964]). Cercospora : duas novas espe! cies do Amazonas e da Bahia. Anais Congresso Sociedade Botanica Brasil 13, 385–388. Brown, J. S. (1975). Investigation of some coconut leaf spots in Papua New Guinea. Papua New Guinea Agriculture Journal 25, 31–42. 731 Cannon, P. F. (1991). A revision of Phyllachora and some similar genera on the host family Leguminosae. Mycological Papers 163, 1–302. Chupp, C. (1953). Monograph of the Fungus Genus Cercospora. Cornell University : Ithaca, New York. Cole, G. T. (1983). Graphiola phoenicis. A taxonomic enigma. Mycologia 75, 93–116. Deighton, F. C. (1985). Three leaf spotting hyphomycetes on palms. Transactions of the British Mycological Society 85, 739–742. Deighton, F. C. (1987). Pseudocercospora carpentariae sp. nov. Transactions of the British Mycological Society 89, 402–404. Duff, J. (1987). Leaf spot diseases of palms. Agnote 314. Northern Territory Department of Agriculture. Ellis, M. B. (1976). More Dematiaceous Hyphomycetes. C.A.B. International : Wallingford, U.K. Ellis, M. B. & Holliday, P. (1972). Drechslera incurvata. CMI Descriptions of Pathogenic Fungi and Bacteria 342. Commonwealth Mycological Institute : Kew. Fischer, E. (1921). Zur Kenntis der Gattung Graphiola. Annales Mycologici 20, 228–237. Forsberg, L. I. (1985). Foliar diseases of nursery-grown ornamental palms in Queensland. Australasian Plant Pathology 14, 67–71. Forsberg, L. I. (1987). Diseases of ornamental palms. Queensland Agricultural Journal Sept.–Oct., 279–286. Fro$ hlich, J. & Hyde, K. D. (1994). New Oxydothis species associated with palm leaf spots in north Queensland, Australia. Mycological Research 98, 213–218. Fro$ hlich, J. & Hyde, K. D. (1995 a). Guignardia candeloflamma sp. nov. causing leaf spots of Pinanga sp. Mycological Research 99, 110–112. Fro$ hlich, J. & Hyde, K. D. (1995 b). Astrosphaeriella frondicola sp. nov. associated with leaf spots on Oraniopsis and other palms. Mycological Research 99, 453–459. Fro$ hlich, J. & Hyde, K. D. (1995 c). Maculatipalma frondicola gen. et sp. nov. causing leaf spots on palms in north Queensland with descriptions of related genera : Apioplagiostoma and Plagiostoma. Mycological Research 99, 727–734. Grgurinovic, C. & Hyde, K. D. (1993). The status of taxonomic mycology in Australia in 1991. Australian Plant Pathology 22, 42–47. Guba, E. F. (1961). Monochaetia and Pestalotia. Harvard University Press : London. Hanlin, R. (1990). Illustrated Genera of Ascomycetes. APS Press : Minnesota, U.S.A. Hawksworth, D. L. (1991). The fungal dimension of biodiversity : magnitude, significance and conservation. Mycological Research 95, 641–655. Hsieh, W.-H. & Goh, T.-K. (1990). Cercospora and Similar Fungi from Taiwan. Maw Chang Book Company : Taiwan. Hughes, S. J. (1952 a). Fungi from the Gold Coast. I. Mycological Papers 48, 1–91. Hughes, S. J. (1952 b). Studies on microfungi. XIV. Mycological Papers 49, 1–25. Hyde, K. D. & Fro$ hlich, J. (1995). Mycosphaerella palmicola associated with leaf spots of Cocos nucifera in Australia, Irian Jaya and Papua New Guinea. Mycological Research 99, 704–706. Hyde, K. D., Pearce, M. H. & Atkinson, D. J. (1991). Exotic plant diseases of concern to the Northern Australian Quarantine Survey. Working papers of the Bureau of Rural Resources : D.P.I.E., Canberra. Killian, M. C. (1924). Le de! veloppement du Graphiola phoenicis Poit. et ses affinite! s. Review of General Botany 36, 385–394, 451–460. Kobayashi, Y. (1952). On the genus Graphiola found in Japan. Nagaoa 1, 32–38. Matsushima, T. (1993). Matsushima Mycological Memoirs No 7. Matsushima Fungus Collection : Kobe, Japan. Moore, H. E. Jr, Uhl, N. & Dransfield, J. (1987). Genera Palmarum. Allen Press : Lawrence, Kansas. Mordue, J. E. M. & Holliday, P. (1971). Pestalotiopsis palmarum. CMI Descriptions of Pathogenic Fungi and Bacteria 319. Morgan-Jones, G. (1977). Notes on Hyphomycetes. XVII. A new species of Pseudospiropes. Mycotaxon 5, 481–483. Oberwinkler, F., Bandoni, R. J., Blanz, P., Deml, G. & Kisimova-Horovitz, L. Fungi and leafspots in north Queensland palms (1982). Graphiolales : basidiomycetes parasitic on palms. Plant Systematics and Evolution 140, 251–271. Pons, N. & Sutton, B. C. (1988). Cercospora and similar fungi on yams (Dioscorea species). Mycological Papers 160, 1–78. Rai, A. N. & Rai, B. (1995). Two new hyphomycetes from India. Mycological Research 99, 1004–1006. Ramanujam, M. P. (1983). Toxin production by Pestalotia palmarum. Current Science 52, 1195–1196. Rao, V. G. & Yadav, B. R. D. (1985). An undescribed species of Phomopsis and its associated ascigenous state. Current Science 54, 385–386. Rao, V. G. & Yadav, B. R. D. (1989). Two undescribed fungi on orchids. Current Science 58, 855–856. (Accepted 25 October 1996) 732 Reid, A. (1988). Palms. Farmnote of the W.A. Department of Agriculture 70, 1–2. Sankaran, K. V., Maria-Florence, E. J. & Sharma, J. K. (1987). Two species of Phomopsis from India. Transactions of the British Mycological Society 89, 404–406. Shivas, R. G. (1992). Phomopsis emicis sp. nov. on Emex australis in South Africa and Western Australia. Mycological Research 96, 75–77. Tominaga, T. (1965). Brown leaf spot of Rhapis flabelliformis L’He! r. caused by Cercospora rhapisicola sp. nov. Transactions of the Mycological Society of Japan 5, 57–59. Turner, P. D. (1981). Oil Palm Diseases and Disorders. Oxford University Press : Selangor, Malaysia.