Damm et al.to olivaceous grey, filter paper Anthriscus stem and medium partlycovered with felty white aerial mycelium (and salmon acervuli),reverse same colours; growth rate 17.5–21.5 mm in 7 d (28.5–31.5mm in 10 d). Colonies on OA flat with entire margin; surface honey,isabelline to olivaceous, almost entirely covered by felty white topale olivaceous grey aerial mycelium, reverse buff, olivaceous,pale olivaceous grey, olivaceous grey to iron-grey, growth rate16–18 mm in 7 d (26–29 mm in 10 d). Conidia in mass salmon.Material examined: Colombia, Cundinamarca, from fruit anthracnose of Solanumbetaceum, 13 Aug. 2010, J. Molina, (<strong>CBS</strong> H-20726 holotype, culture ex-type <strong>CBS</strong>129814 = T.A.6); Cundinamarca, from anthracnose on a fruit of Solanum betaceum,13 Aug. 2010, J. Molina, culture <strong>CBS</strong> 129811 = T.A.3; Antioquia, Santa Rosa, from aflower of Solanum betaceum, 1998, collect<strong>or</strong> unknown, <strong>CBS</strong> H-20728, culture <strong>CBS</strong>129955 = Tom-12.Notes: Afanad<strong>or</strong>-Kafuri et al. (2003) identified several strains fromtamarillo in Colombia as C. acutatum, three of which are included inthis study. Sreenivasaprasad & Talhinhas (2005) recognised thesestrains as a separate molecular group, A8, closely related to A1 (C.lupini).<strong>Colletotrichum</strong> tamarilloi can be separated from other <strong>species</strong>using CHS-1, HIS3, TUB2 and GAPDH sequences, most effectivelywith GAPDH, and f<strong>or</strong>ms a unif<strong>or</strong>m cluster even with six genes (Fig.1). Afanad<strong>or</strong>-Kafuri et al. (2003) observed unif<strong>or</strong>mity of bandingpatterns with apPCR, RAPD-PCR and A+T-rich DNA analyses ofthe strains they studied. They speculated that selection f<strong>or</strong> clonalityand homogeneity had occurred among the isolates, all of whichwere collected in one region in Colombia where only one cultivarof the host was cultivated. Conidia of C. tamarilloi are unif<strong>or</strong>mlyfusif<strong>or</strong>m on SNA, and almost so on Anthriscus stem, while C. lupinif<strong>or</strong>ms conidia that are usually clavate on SNA and cylindrical onthe stems. Additionally, we found that appress<strong>or</strong>ia of C. lupini havean undulate to lobate margin, while those of C. tamarilloi have anentire <strong>or</strong> rarely slightly undulate edge.This <strong>species</strong> is only known on Solanum betaceum in Colombia.There are no previously described <strong>species</strong> associated with thishost. Three <strong>Colletotrichum</strong> <strong>species</strong> are rep<strong>or</strong>ted from tamarillo inthe USDA fungal databases (Farr & Rossman 2012): C. acutatum(Guerber et al. 2003, Gadgil 2005) and C. gloeosp<strong>or</strong>ioides (Gadgil2005) in New Zealand and C. simmondsii in Australia (Shivas & Tan2009). None of these <strong>species</strong>/groups is identical with C. tamarilloi.While C. lupini and C. tamarilloi f<strong>or</strong>m well-supp<strong>or</strong>ted clusters, thereare several additional <strong>species</strong> and unnamed strains from varioushosts in Central and South America, as well as in Fl<strong>or</strong>ida that areclosely related to C. lupini and C. tamarilloi. One of these is fromtamarillo in the same locality in Colombia (<strong>CBS</strong> 129810).A recently rep<strong>or</strong>ted anthracnose pathogen of tamarillo inthe USA (Jones & Perez 2012) probably belongs to C. fi<strong>or</strong>iniaeacc<strong>or</strong>ding to its ITS sequence (JN863589). The <strong>Colletotrichum</strong>strains available to us from tamarillo in Colombia and New Zealandbelong to C. godetiae, C. tamarilloi and an unnamed strain relatedto C. tamarilloi (this study), as well as C. boninense, C. constrictumand C. karstii belonging to the C. boninense <strong>species</strong> <strong>complex</strong>(Damm et al. 2012, this issue). Yearsley et al. (1988) rep<strong>or</strong>t C.acutatum (s. lat.) infections of tamarillo in New Zealand; howevernone of our tamarillo strains isolated from New Zealand belongsto the C. acutatum group. The strains from this host included inGuerber et al. (2003) and assigned to group F2 f<strong>or</strong>med a clade withstrains described as C. johnstonii in this study. We did not find any<strong>species</strong> on tamarillo occurring in both Colombia and New Zealand.Falconi & van Heusden (2011) studied <strong>Colletotrichum</strong> isolatescollected from Lupinus mutabilis and tamarillo in the Ecuad<strong>or</strong>ianAndes. They f<strong>or</strong>med two different subgroups within C. acutatumbased on ITS sequence data. The isolates from lupins werepathogenic to tamarillo and vice versa, but lupin and tamarilloisolates were each m<strong>or</strong>e virulent to their own hosts. ITS sequenceof the ex-type strain of C. tamarilloi, <strong>CBS</strong> 129814, matched with100 % identity with JN543070 from isolate Tam7 from tamarillo, aswell as JN543066 from isolate Lup28 from L. mutabilis in Ecuad<strong>or</strong>(Falconi et al. 2012).The closest TUB2 blastn matches f<strong>or</strong> <strong>CBS</strong> 129814 (with 99% identity, 4 bp differences) were FN611029 and FN611028 fromisolates DPI and CS-1 from Citrus aurantifolia and Citrus sinensisfrom USA, Fl<strong>or</strong>ida (Ramos et al. 2006). The closest GAPDHmatches (with 97 % identity) were EU647323 from leatherleaf fernand EU168905, EU647318 and EU647319 from sweet <strong>or</strong>angeisolates, all from Fl<strong>or</strong>ida, USA (Peres et al. 2008, MacKenzie etal. 2009).<strong>Colletotrichum</strong> walleri Damm, P.F. Cannon & Crous, sp.nov. MycoBank MB800517. Fig. 32.Etymology: Named after J.M. Waller, tropical pathologist extra<strong>or</strong>dinaireand a key w<strong>or</strong>ker on the most imp<strong>or</strong>tant <strong>Colletotrichum</strong>pathogen of coffee.Sexual m<strong>or</strong>ph not observed. Asexual m<strong>or</strong>ph on SNA. Vegetativehyphae 1–6 µm diam, hyaline, smooth-walled, septate, branched.Chlamydosp<strong>or</strong>es not observed. Conidiomata not developed,conidioph<strong>or</strong>es f<strong>or</strong>med directly on hyphae. Setae not observed.Conidioph<strong>or</strong>es hyaline, smooth-walled, septate, branched, to 70µm long. Conidiogenous cells hyaline, smooth-walled, cylindrical toampullif<strong>or</strong>m, 10–14 × 3–4 µm, opening 1–1.5 µm diam, collarette0.5–1 µm long, periclinal thickening distinct. Conidia hyaline,smooth-walled, aseptate, straight, cylindrical to fusif<strong>or</strong>m with bothends slightly acute <strong>or</strong> one end round, (6–10.5)15.5–(–19.5) ×(3–)3.5–4.5(–5.5) µm, mean ± SD = 13.0 ± 2.7 × 4.0 ± 0.5 µm,L/W ratio = 3.3. Appress<strong>or</strong>ia single, medium brown, smooth-walled,elliptical, clavate, sometimes irregularly shaped, the edge entire <strong>or</strong>undulate, (4.5–)5.5–12.5(–18.5) × (3.5–)4.5–7.5(–10.5) µm, mean± SD = 9.0 ± 3.3 × 5.9 ± 1.4 µm, L/W ratio = 1.5.Asexual m<strong>or</strong>ph on Anthriscus stem. Conidiomata either notdeveloped, conidioph<strong>or</strong>es f<strong>or</strong>med directly on hyphae, <strong>or</strong> acervular,conidioph<strong>or</strong>es f<strong>or</strong>med on pale brown, angular, basal cells 3.5–7 µmdiam. Setae not observed. Conidioph<strong>or</strong>es hyaline to pale brown,smooth-walled, septate, branched, to 70 µm long. Conidiogenouscells hyaline to pale brown, smooth-walled, cylindrical, 12–23× 2.5–3 µm, opening 1–1.5 µm diam, collarette 0.5–1 µm long,periclinal thickening visible to distinct. Conidia hyaline, smoothwalled,aseptate, straight, sometimes slightly curved, cylindrical tofusif<strong>or</strong>m with both ends ± acute <strong>or</strong> one end round, (10.5–)12–16(–18.5) × 3.5–4(–4.5) µm, mean ± SD = 13.9 ± 1.8 × 4.0 ± 0.3 µm,L/W ratio = 3.5.Culture characteristics: Colonies on SNA flat with entire margin,hyaline, filter paper pale olivaceous grey, medium, filter paper andAnthriscus stem covert with fely white aerial mycelium, reversesame colours; 21–24 mm in 7 d (31–34 mm in 10 d). Colonies onOA flat with entire margin; surface covert with felty <strong>or</strong> sh<strong>or</strong>t floccosewhite to pale olivaceous grey aerial mycelium, reverse olivaceousgrey to iron grey, olivaceous in the centre and white towards themargin; 20–26 mm in 7 d (30.5–37.5 mm in 10 d). Conidia in masssalmon.106
The <strong>Colletotrichum</strong> acutatum <strong>species</strong> <strong>complex</strong>Fig. 32. <strong>Colletotrichum</strong> walleri (from ex-holotype strain <strong>CBS</strong> 125472). A–B. Conidiomata. C–H. Conidioph<strong>or</strong>es. I–N. Appress<strong>or</strong>ia. O–P. Conidia. A, C–E, O. from Anthriscus stem.B, F–N, P. from SNA. A–B. DM, C–P. DIC, Scale bars: A = 100 µm, C = 10 µm. Scale bar of A applies to A–B. Scale bar of C applies to C–P.Material examined: Vietnam, Buon Ma Thuot-Dak Lac, from leaf tissue of Coffeaarabica, unknown collection date, H. Nguyen, (<strong>CBS</strong> H-20795 holotype, culture extype<strong>CBS</strong> 125472 = BMT(HL)19).Notes: Species of the C. gloeosp<strong>or</strong>ioides <strong>species</strong> <strong>complex</strong> arewell-known as pathogens of Coffea, especially the African coffeeberry disease pathogen C. kahawae (Waller et al. 1993). AdditionalCoffea-associated components of this <strong>species</strong> <strong>complex</strong> fromVietnam and Thailand have been studied by Nguyen et al. (2009)and Prihastuti et al. (2009); see Weir et al. (2012, this issue) f<strong>or</strong>further review.Masaba & Waller (1992) commented that strains identified asC. acutatum may cause min<strong>or</strong> disease of ripening coffee berries.Kenny et al. (2006) and Nguyen et al. (2010) respectively isolated,in Papua New Guinea and Vietnam, taxa in this <strong>species</strong> <strong>complex</strong>from coffee leaves, twigs and fruits. None of the Vietnameseisolates could infect undamaged coffee berries (Nguyen et al.2010). One of the C. acutatum cultures studied by Nguyen et al.(BMT(HL)19) was sent to <strong>CBS</strong> and a dried sample of this strain ishere designated as holotype of C. walleri. In this study, this is theonly coffee isolate from Asia, while six other isolates from coffee,<strong>or</strong>iginating from Africa and Central America, belong to three other<strong>species</strong> within the C. acutatum <strong>species</strong> <strong>complex</strong> (C. fi<strong>or</strong>iniae, C.acutatum s. str. and C. costaricense). Two of these strains wereincluded in the study by Waller et al. (1993).<strong>Colletotrichum</strong> walleri is separated from other <strong>species</strong> byalmost all genes. It is most easily distinguished using HIS3 and ITSsequences, while sequences of other genes differ by only one bpfrom those of other <strong>species</strong>. The CHS-1 sequence is the same asthat of C. sloanei. The closest TUB2 blastn match f<strong>or</strong> <strong>CBS</strong> 125472(with 99 % identity, 5 bp differences) was GU246633 from isolateR14 from Capsicum annuum from South K<strong>or</strong>ea (Sang et al. 2011).The closest GAPDH match f<strong>or</strong> a sequence covering ± the fullgene length (with 98 % identity, 4 bp differences) was HQ846724from isolate OBP6 from an unnamed plant, probably from India(Chowdappa P, Chethana CS, Madhura S, unpubl. data). The only100 % match with the ITS sequence was FJ968601, the sequenceof the same isolate previously sequenced by Nguyen et al. (2009).DISCUSSION<strong>Colletotrichum</strong> acutatum (in the broad sense) was <strong>or</strong>iginallydistinguished using m<strong>or</strong>phological characteristics. The primarydiagnostic feature was given as the possession of fusif<strong>or</strong>m conidiawith acute ends (Simmonds 1965). M<strong>or</strong>e detailed research hashowever shown that this characteristic is not absolute; while moststrains of <strong>species</strong> within the C. acutatum <strong>complex</strong> have at least aprop<strong>or</strong>tion of conidia with at least one acute end, it is common tofind significant variation in conidial shape within <strong>species</strong> and evenwithin individual strains. Conidia that are m<strong>or</strong>e <strong>or</strong> less cylindricalare frequently encountered. The variation may have multiplecauses; in some circumstances it seems that secondary conidiawww.studiesinmycology.<strong>or</strong>g107