Three new species of soil-inhabiting Trichoderma from southwest China

Abstract

Fungi in the genus Trichoderma are widely distributed in China, including in Yunnan province. In this study, we report three new soil-inhabiting species in Trichoderma, named as T.kunmingense, T.speciosum and T.zeloharzianum. Their colony and mycelial morphology, including features of asexual states, were described. For each species, their DNA sequences were obtained from three loci, the internal transcribed spacer (ITS) regions of the ribosomal DNA, the translation elongation factor 1-α encoding gene (tef1) and the gene encoding the second largest nuclear RNA polymerase subunit (rpb2). Our analyses indicated that the three new species showed consistent divergence amongst each other and from other known and closely related species. Amongst the three, T.speciosum and T.kunmingense belong to the Viride Clade. Specifically, T.speciosum is related to three species – T.hispanicum, T.samuelsii and T.junci and is characterised by tree-like conidiophores, generally paired branches, curved terminal branches, spindly to fusiform phialides and subglobose to globose conidia. In contrast, T.kunmingense morphologically resembles T.asperellum and T.yunnanense and is distinguished by its pyramidal conidiophores, ampulliform to tapered phialides, discrete branches and ovoidal, occasionally ellipsoid, smooth-walled conidia. The third new species, T.zeloharzianum, is a new member of the Harzianum Clade and is closely associated with T.harzianum, T.lixii and T.simmonsii but distinguished from them by having smaller, subglobose to globose, thin-walled conidia.

Four new species of Trichoderma in the Harzianum clade from northern China

“…The genus Trichoderma Pers., introduced by Persoon (1794), is cosmopolitan, including saprotrophs and mycoparasites in a diversity of ecosystems, such as agricultural fields, prairies, forests, salt marshes, and fungal fruiting body ( Gazis and Chaverri 2010 ; Chaverri et al 2015 ; Qiao et al 2018 ). Species of this genus have been widely used in the biocontrol of plant pathogens ( Chaverri et al 2015 ; Degenkolb et al 2015 ; Bunbury-Blanchette and Walke 2019) and production of enzymes and bioactive compounds ( Sun et al 2016 ).…”

“…Nevertheless, some of them are associated with green mold diseases in the commercial production of mushrooms ( Innocenti et al 2019 ; Sun et al 2019a ) . Morphologically, the asexual-morphs are similar in producing branched tree-like conidiophores with cylindrical to nearly subglobose phialides and ellipsoidal to globose conidia, but their variation is insufficient to differentiate the Trichoderma species ( Chaverri et al 2015 ; Qin and Zhuang 2017 ; Qiao et al 2018 ). Multilocus molecular phylogeny, based on combined sequence data of the internal transcribed spacer ( ITS ) regions, RNA polymerase II subunit ( RPB2 ), and the translation elongation factor 1-α gene ( TEF1-α ), enables rapid and accurate identification of the Trichoderma species ( Druzhinina et al 2005 ; Atanasova et al 2013 ; Chaverri et al 2015 ).…”

“…Multilocus molecular phylogeny, based on combined sequence data of the internal transcribed spacer ( ITS ) regions, RNA polymerase II subunit ( RPB2 ), and the translation elongation factor 1-α gene ( TEF1-α ), enables rapid and accurate identification of the Trichoderma species ( Druzhinina et al 2005 ; Atanasova et al 2013 ; Chaverri et al 2015 ). Currently, the combination of multi-gene phylogenetic analysis and phenotypic characteristics is extensively applied in species delimitation of Trichoderma ( du Plessis et al 2018 ; Qiao et al 2018 ; Innocenti et al 2019 ).…”

“…As a cosmopolitan and ubiquitous fungus, it has been isolated from diverse substrates, such as soil, plant tissue, and mushrooms ( Chaverri et al 2015 ; Jaklitsch and Voglmayr 2015 ; Innocenti et al 2019 ; Sun et al 2019b ). Since Chaverri et al (2015) provided a systematic revision of species in the Harzianum clade, numerous new species have been described ( Jaklitsch and Voglmayr 2015 ; Qin and Zhuang 2016a ; Sun et al 2016 ; Chen and Zhuang 2017b ; Qiao et al 2018 ). Currently, more than 60 species are placed in the Harzianum clade ( Jaklitsch and Voglmayr 2015 ; Qin and Zhuang 2016a , b , 2017 ; Chen and Zhuang 2017b ; Qiao et al 2018 ; Phookamsak et al 2019 ;) .…”

Remotididymella ageratinae sp. nov. and Remotididymella anemophila sp. nov., two novel species isolated from the invasive weed Ageratina adenophora in PR China

“…A new genus and species, Blastosporium persicolor Z.F. Yu & H. Zheng has been described and illustrated from leaves of mildewed tobacco [20]. Memnoniella sinensis Hua Zheng et al was identified in a deserted rocky area in Yunnan [21].…”