Neofusicoccum Crous, Slippers & A.J.L. Phillips, Studies

Pereira, Diana S. & Phillips, Alan J. L., 2023, Botryosphaeriaceae on palms-a new species of Neodeightonia, N. chamaeropicola, and new records from diseased foliage of ornamental palms in Portugal, Phytotaxa 627 (1), pp. 1921-1935 : 1921-1935

Neofusicoccum Crous, Slippers & A.J.L. Phillips, Studies in Mycology 55: 247 (2006), MycoBank MB500870

Neofusicoccum , based on N. parvum isolated from a dead branch of Populus nigra in New Zealand, was introduced by Crous et al. (2006) to accommodate species morphologically similar to, but phylogenetically distinct from Botryosphaeria . Some morphological characters have been used to differentiate these two genera, such as the presence of a Dichomera synasexual morph in Neofusicoccum species. However, this may not be a reliable character since not all Neofusicoccum species form a Dichomera synasexual morph, and some isolates of B. dothidea have been reported to form such a synasexual morph. A more reliable morphological difference is the absence of paraphyses in the conidiomata of Neofusicoccum species, which have been seen in most Botryosphaeria species ( Barber et al. 2005, Phillips et al. 2005, 2013). Species in Neofusicoccum are thus characterized by Botryosphaeria -like sexual morphs, Dichomera -like synasexual morphs and Fusicoccum -like asexual morphs, with conidia that are more ellipsoidal than the fusiform ones found in Fusicoccum s. str., with conidial L/W ratios less than 4 ( Phillips et al. 2013). Species in Neofusicoccum are difficult to differentiate from one other since many morphological characters overlap between species or are not stable between isolates of a given species. Thus molecular data are required to distinguish species ( Crous et al. 2006, Phillips et al. 2008, Sakalidis et al. 2011, Abdollahzadeh et al. 2013, Phillips et al. 2013, Marin-Felix et al. 2017, Zhang et al. 2021a). Neofusicoccum species have a worldwide and cosmopolitan distribution and are known as endophytes and pathogens causing shoot blight, cankers and dieback on a wide range of woody hosts, including wild, ornamental and economically important species ( Slippers & Wingfield 2007, Sakalidis et al. 2013, Pavlic-Zupanc et al. 2015, Brewer et al. 2021, Hattori et al. 2021). Given the last synonymies proposed and taxa introduced, Neofusicoccum presently includes 47 species based on both morphology and phylogenetic analyses ( Brewer et al. 2021, Crous et al. 2021, Hattori et al. 2021, Tennakoon et al. 2021, Zhang et al. 2021 a,b, Xu et al. 2022, Si et al. 2023, present study). Nonetheless, many lineages in the genus continue to be confused, especially in the N. parvum / N. ribis species complex where 10 cryptic species have been identified and many others have been recently synonymised ( Pavlic et al. 2009, Begoude et al. 2010, Sakalidis et al. 2011, 2013, Slippers et al. 2017, Zhang et al. 2021a).

Neofusicoccum australe (Slippers, Crous & M.J. Wingf.) Crous, Slippers & A.J.L. Phillips, Studies in Mycology 55: 248 (2006), MycoBank MB500873

Type: AUSTRALIA, Victoria, Batemans Bay, on Acacia sp. ( Fabaceae ), date unknown, M. J. Wingfield (holotype PREM 57589, culture ex-type CMW 6837).

Sexual morph and asexual morph reported. See Phillips et al. (2013) for illustrations and descriptions.

Isolate CDP 0075. Sexual morph: Undetermined. Asexual morph: Undetermined.

Culture characteristics: Colonies on 1/2 PDA, reaching 80 mm diam. after 7 d at 20 ℃ in darkness. Surface flat, with sparse aerial mycelium, with filamentous margin, irregular to circular shape, whitish to pale, becoming brownish towards the centre, opaque. Reverse pale, becoming brownish towards the centre. Turning entirely orangish to dark brown (reverse) after about 2 w. No diffusible pigment.

Material examined: PORTUGAL, Lisbon, Marvila, Rua Jorge Amado, on foliar lesions of leaflets of Phoenix canariensis ( Arecaceae ), 6 October 2018, Diana S. Pereira (specimen HDP 019), living culture CDP 0075 ( ITS sequence OQ996218, tef1 sequence OR 233666).

Hosts: Reported from more than 50 genera in 28 families, including Anacardiaceae ( Mangifera indica , Pistacia vera ), Apiaceae ( Ferula communis ), Araucariaceae ( Wollemia nobilis ), Arecaceae ( Phoenix canariensis ), Casuarinaceae ( Allocasuarina fraseriana ), Cupressaceae ( Callitris preissii , Chamaecyparis lawsoniana , Cupressus lusitânica , Sequoia sempervirens , Sequoiadendron sp. , S. giganteum , Thuja plicata , Thujopsis dolabrata , Widdringtonia nodiflora ), Ebenaceae ( Diospyros kaki ), Elaeocarpaceae ( Elaeocarpus holopetalus ), Ericaceae ( Arctostaphylos glauca , Vaccinium sp. , V. corymbosum ), Fabaceae ( Acacia sp. , A. cochlearis , A. karroo , A. longifolia , A. mearnsii , A. rostellifera , Cytisus scoparius , Robinia pseudoacacia , Vachellia karroo ), Fagaceae ( Castanea sativa , Quercus agrifolia , Q. robur ), Hydrangeaceae ( Hydrangea macrophylla ), Juglandaceae ( Juglans sp. ), Lauraceae ( Persea americana ), Malvaceae ( Tilia platyphyllos ), Meliaceae ( Melia azedarach ), Myrtaceae ( Agonis flexuosa , Callistemon viminalis , Corymbia maculate , Eucalyptus diversicolor , E. globulus , E. gomphocephala , E. grandis , E. marginata , Syzygium cordatum ), Oleaceae ( Fraxinus excelsior , Olea europaea ), Pinaceae ( Picea abies , Pinus halepensis , P. pinaster , P. pinea ), Proteaceae ( Banksia sp. , B. caleyi , B. grandis , Macadamia integrifolia , Protea sp. , P. cynaroides ), Rosaceae ( Malus domestica , Prunus armeniaca , P. domestica , P. dulcis , P. persica , P. salicina , Pyracantha coccinea , Pyrus communis ), Rutaceae ( Citrus sp. , C. sinensis , C. unshiu ), Salicaceae ( Populus alba , Salix sp. ), Santalaceae ( Santalum acuminatum ), Taxaceae ( Taxus baccata ), Ulmaceae ( Ulmus minor ), Vitaceae ( Vitis sp. , V. vinifera ) and Zamiaceae ( Dioon spinulosum ) ( Farr & Rossman 2023).

Distribution: Algeria, Australia, Chile, Italy (including Sicily), Mexico, New Zealand, Portugal, South Africa (including the Eastern Cape, Gauteng, KwaZulu-Natal and Western Cape provinces), Spain (including Canary Islands), Tunisia, Turkey, Uruguay and USA (California) ( Farr & Rossman 2023).

Notes: Based on the phylogenetic analyses of the combined ITS- tef1-tub2 dataset, strain CDP 0075 clustered with the ex-type strain and other strains of Neofusicoccum australe with high ML-BS/PP values ( Figure 5 ). Sequence comparisons with the ex-type of N. australe ( CMW 6837) for ITS and tef1 showed 100 % and 96.62 %, respectively, sequence similarity and difference in tef1 partial sequence are represented by a single nucleotide change. No tub2 sequence data is available for CDP 0075. Despite numerous attempts with different temperatures and with different organic material introduced on the agar surface, isolate CDP 0075 remained sterile even after long periods of incubation about 2 months. For this reason, morphological comparisons with the ex-type of N. australe were not possible. Based on the molecular analyses carried in the present study, strain CDP 0075 was identified as N. australe . Neofusicoccum australe has not previously been recorded on Arecaceae and thus a new host record is here reported for Phoenix canariensis in Portugal ( Table 5). The isolate of N. australe studied here was recorded from foliar lesions of P. canariensis , but pathogenicity has not been tested.

Figures

FIGURE 5. Phylogenetic tree of Neofusicoccum generated from BA inference based on combined ITS, tef1 and tub2 sequences. ML bootstrap support values (ML-BS ≥ 50 %) and Bayesian posterior probabilities (PP ≥ 0.85) are shown at the nodes. Strains with type status are indicated in bold font, the isolates from this study are presented in brown typeface and species are delimited with coloured blocks. Species names in N. parvum species complex are noted before the strain number. The scale bar represents the expected number of nucleotide changes per site. The tree was rooted to Botryosphaeria corticis (CBS 119047) and B. dothidea (CBS 115476).