Pestalotiopsis and allied genera from Camellia, with description of 11 new species from China

Abstract

A total of 124 Pestalotiopsis-like isolates associated with symptomatic and asymptomatic tissues of Camellia sinensis and other Camellia spp. from eight provinces in China were investigated. Based on single-and multi-locus (ITS, TEF, TUB2) phylogenies, as well as morphological characters, host associations and geographical distributions, they were classified into at least 19 species in three genera, i.e. Neopestalotiopsis, Pestalotiopsis and Pseudopestalotiopsis. Eight novel species in Pestalotiopsis and three novel species in Pseudopestalotiopsis were described. Our data suggested that the currently widely used loci in Pestalotiopsis-like genera do not consistently provide stable and sufficient resolution tree topologies, especially for Neopestalotiopsis. Moreover, the number, branch pattern and length of the conidial basal appendages were revealed to be phylogenetically informative characters in Pestalotiopsis.Camellia sinensis (L.) Kuntze, widely grown in the tropics and subtropics, are commonly processed to produce popular beverage-tea. Many other species of Camellia are commercially important ornamentals, such as C. japonica, C. oleifera and C. sasanqua. According to the USDA database, 520 fungal species have been known to occur on Camellia spp., of which 303 were from C. sinensis 1 . In our national wide investigation of fungi on C. sinensis in China, we have identified several dominant genera, namely Colletotrichum 2 , Diaporthe 3 and Pestalotiopsis. While several studies documented Pestalotiopsis species occurring on tea planHowever, in the gene trees of Neopestalotiopsits 4-7 .Some Pestalotiopsis species are known to cause diseases of foliage, stems and roots and cause considerable reduction on commercial production 5,6,8,9 . For instance, grey blight disease of tea plants caused by Pestalotiopsis spp. resulted in 17% production loss in southern India 8 and 10-20% yield loss in Japan 9 .Traditionally taxonomy of Pestalotiopsis was limited to naming species according to the host from which they were first observed and the conidial morphologies such as colour intensities of the median conidial cell 10,11 . With the introduction of multi-locus DNA sequence analyses, the traditional host-based classification system and the division of the groups and species based on conidial characters proved to be unreliable [12][13][14][15][16][17][18] . The use of molecular data in resolving Pestalotiopsis species was recently reviewed by Maharachchikumbura et al. 18 , and two new genera were established, i.e. Neopestalotiopsis and Pseudopestalotiopsis (Ps.). Up to now, seven species in Pseudopestalotiopsis and 25 in Neopestalotiopsis have been introduced 4, 17-19 , and 52 species in Pestalotiopsis have been phylogenetic verified 2,17,18,[20][21][22] . Among above, only four were associated with C. sinensis, i.e. P. camelliae, P. furcate, Ps. ignota, Ps. theae [4][5][6] .The current study aimed to investigate the taxonomic and phylogenetic diversity of Pestalotiopsis-like species associated with C. sinensis and other Cam...

Characterization of Neopestalotiopsis Species Associated with Mango Grey Leaf Spot Disease in Sinaloa, Mexico

“…The alignment contained 1500 characters (521 for ITS, 483 for TUB, and 496 for TEF) and the combined datasets resulted in a best scoring RAxML tree with a final maximum likelihood (ML) optimization value of likelihood of −6532.281881, shown in Figure 4 . The overall topology of our tree is comparable to that of earlier studies [ 17 , 20 , 32 ]. However, the overall branch-length support values were lower in most clades and recent studies have shown that the use of combined ITS, TEF, and TUB sequences to resolve numbers of cryptic species in pestalotiopsis-like taxa have some shortcomings.…”

“…The overall topology of our phylogenetic tree was not sufficiently supported, similar to that published in previous studies that maintained the Neopestalotiopsis isolates as Neopestalotiopsis spp. [ 17 , 32 , 33 , 34 , 35 ]. Although multi-locus phylogeny is important in species differentiation, there is still a lack of species deposited in public culture collections and only a fraction of DNA has been sequenced [ 36 ].…”

Unambiguous identification of fungi: where do we stand and how accurate and precise is fungal DNA barcoding?

“…Phenotypically cryptic speciation and convergent evolution are frequent in fungi (Crespo and Pérez-Ortega 2009;Cai et al 2011;Moncada et al 2014;Balasundaram et al 2015;Jayawardena et al 2016;Liu et al 2017;Kruse et al 2018b). Formal taxonomy that recognizes cryptic species may appear impractical because the molecular tools necessary for precise identification are out of reach for many users.…”

Allelochaeta (Sporocadaceae): pigmentation lost and gained

“…Likewise, Pseudopestalotiopsis was distinguished from Pestalotiopsis by generally dark coloured concolourous median cells with indistinct conidiophores. However, Liu et al (2017) found that there were exceptions, and that some taxa clustering within Neopestalotiopsis produced concolourous median cells, suggesting that conidial pigmentation is more plastic among these genera than originally proposed by Maharachchikumbura et al (2014).…”