MYCOBIOLOGY 2018, VOL. 46, NO. 3, 177–184 https://doi.org/10.1080/12298093.2018.1497792 RESEARCH ARTICLE New Report of Three Unrecorded Species in Trichoderma harzianum Species Complex in Korea Seokyoon Janga, Sun Lul Kwona, Hanbyul Leea, Yeongseon Jangb, Myung Soo Parkc, Young Woon Limc, Changmu Kimd and Jae-Jin Kima aDivision of Environmental Science & Ecological Engineering, College of Life Science & Biotechnology, Korea University, Seoul, Korea; bDivision of Wood Chemistry and Microbiology, National Institute of Forest Science, Seoul, Korea; cSchool of Biological Sciences and Institute of Microbiology, Seoul National University, Seoul, Korea; dMicroorganism Resources Division, National Institute of Biological Resources, Inceon, Korea ABSTRACT ARTICLE HISTORY The genus Trichoderma (Hypocreaceae, Ascomycota) consists of globally distributed fungi. Received 7 November 2017 Among them, T. harzianum, one of the most commonly collected Trichoderma species, had Revised 22 April 2018 been known as a polyphyletic or aggregate species. However, a total of 19 species Accepted 5 May 2018 were determined from the polyphyletic groups of T. harzianum. Thus, we explored Korean “T. harzianum” – KEYWORDS specimens that were collected in 2013 2014. These specimens were re-exam- a a EF1 ; phylogeny; taxonomy; ined based on a recent study with translate elongation factor 1-alpha (EF1 ) sequences to Trichoderma; Trichoderma reveal cryptic Trichoderma species in Korea. As a result, four different species, T. afroharzia- harzianum species complex num, T. atrobruneum, T. pyramidale, and T. harzianum, were identified. Except T. harzianum, the other three species have not been reported in Korea. In this work, we describe these species and provide figures. 1. Introduction species complex [6,11]. In 2015, their cryptic species were re-evaluated by phylogenetic analysis with The genus Trichoderma Persoon (type species: T. translate elongation factor 1-alpha (EF1a) sequences, viride Pers) is a large group of ascomycetous fungi that contains more than 250 species [1]. Some of and they were described as 14 new species [4]. the Trichoderma species are economically important Among them, the well-known biological control because they produce industrial enzymes and antibi- agent T. harzianum T22 was determined to be T. otics [2,3]. They can be applied as biocontrol agents afroharzianum, and the well-known teleomorphic “ ” against plant pathogens [2–4]. Morphologically, species of T. harzianum, Hypocrea lixii Pat. , was their colonies are typically fast-growing and green- re-named to be T. lixii (Pat.) P. Chaverri [4]. colored; conidiophores are loosely or compactly In Korea, T. harzianum was reported for the first tufted and often form concentric rings; microscopic- time by Lee and Lee (1980), and approximately four ally, the typical conidiophore is pyramidal with species of the Harzianum group have been reported paired branches, terminating in one or a few phia- to date: T. pleuroti, T. pleuroticola, T. harzianum, lides; and conidia are typically ellipsoidal or rarely and T. tomentosum [8,12,13]. Three out of these a globose [5]. four species were identified with EF1 sequences, T. harzianum Rifai is known as the most common but T. harzianum has not been tested in Korea to species within the genus worldwide [6]. This species create a detailed phylogeny [8,12,13]. Thus, we is commonly found on various substrates such as expected that some Korean cultures identified as “T. soil, wood, and other fungi [2–4,7–9]. Additionally, harzianum” might be different species. T. harzianum is an economically important species Both morphological and molecular biological because of its remarkable bioactive abilities, particu- methods have been used to research the taxonomy larly its cellulolytic enzymes and anti-fungal abil- of Trichoderma [4,14]. However, species in the ity [2,4,10]. Harzianum group are morphologically very similar, T. harzianum has been known as an aggregate and the internal transcribed spacer rDNA (ITS), the species because they are very similar and are poly- most universal fungal molecular barcode, has a spe- phyletic [6]. Thus, they are named the T. harzianum cies resolution for this group that is too low [4]. For CONTACT Jae-Jin Kim [email protected] ß 2018 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group on behalf of the Korean Society of Mycology This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. 178 S. JANG ET AL. molecular biological analysis, recent studies used than 30 units of each element were measured, and several DNA regions: actin (ACT), calmodulin 5% of the measurements from each end of the range (CAL), ITS, RNA polymerase II (RPB2), and EF1a were removed and they were noted in parenthesis. [4,8,9,11,13,14]. Among them, EF1a is the most rec- The isolates were deposited at NIBR. ommended DNA region for single-region analysis, and it has shown high species resolution for phyl- 2.2. Phylogenetic analysis ogeny of Trichoderma [4,13]. Since 2013, we have studied the diversity of Genomic DNAs of seven strains were extracted with Trichoderma in Korea and collected many “T. Accuprep Genomic DNA extraction kit (Bioneer, harzianum” isolates. However, a poly-phylogenetic Daejeon, Korea). PCR reactions were carried out group was revealed by the phylogenetic analysis according to the previously described method [11]. based on EF1a. To determine the identities of Theprimerset:EF1-728F[16], and TEF1–rev were recently collected “T. harzianum”, the cultures in used [14]. The PCR products were sequenced by Korea University Culture Collection (KUC; Korea Sanger method with 3730xl DNA Analyzer (Life tech- Univ., Seoul, Korea) were re-analyzed with EF1a nology; Carlsbad, CA, USA) by Macrogen sequences. Among them, four species, T. afroharzia- (Seoul, Korea). num, T. atrobruneum, T. pyramidale, and T. harzia- The obtained EF1a were aligned with the selected num, were identified. Of these four species, only T. reference sequences including type specimen from harzianum has previously been reported in Korea. GenBank using MAFFT 7.130 [17], and modified These species were morphologically examined and manually with MacClade 4.08 [18]. The data metrics described in detail, T. afroharzianum, T. atrobru- contained 29 taxa and 686 characters and their suit- neum, and T. pyramidale, were newly reported. able DNA evolution model were tested by MrModeltest 2.3 using the AIC criteria with default options [19]. The HKY þ G model was chosen 2. Materials and methods under the AIC criteria. Bayesian analysis was carried 2.1. Analysis of phenotype out with MrBayes 3.2.1 [20]. Phylogenetic tree was A total of seven Trichoderma strains were obtained constructed according to previously described from Korea University Collection (KUC, Seoul, method [21]. Korea). They were deposited in National Institute of Biological Resources (NIBR, Incheon, Korea). T. 3. Results harzianum SFC20151215-09M was received from 3.1. Phylogenetic identification of T. harzianum Marine Fungal Resource Bank (http://mfrb.snu.ac.kr; species complex Seoul, Korea). They were previously identified as members of Harzianum group using ITS sequence The sequences of the T. harzianum species complex analysis. They were examined on three types of were re-identified by phylogenetic analysis based on media: corn meal dextrose agar (CMD: cornmeal the EF1a region (Figure 1). The tree contains 29 taxa 20 g/L, glucose 20 g/L, agar 18 g/L), potato dextrose of Trichoderma spp. Our sequences were classified agar (PDA: DifcoTM potato dextrose agar 39 g/L) or into four clades with the reported species. KUC21203, synthetic nitrogen-poor or nutrient-poor agar (SNA, KUC21205, KUC21207, and SFC20151215-M09 synthetischer n€ahrstoff€armer agar: sucrose 0.2 g/L, formed a clade with the type specimen of T. harzia- glucose 0.2 g/L, KNO3 1 g/L, KH2PO4 1 g/L, num with 100% posterior probabilities (PP). Á MgSO4 7H2O 0.5 g/L, NaCl 0.5 g/L, agar 12 g/L). All KUC21213 and KUC21214 were identified as T. afro- media were quantified as 20 mL in 90 mm-diameter harzianum with high PP (100%). KUC21091 and plastic Petri dishes. To analyze morphologies of col- KUC21123 were grouped with T. pyramidale and T. ony, 6 mm-diameter. plug of cultures were inocu- atrobrunneum, respectively, with high PP (100% and lated about 1.5 cm from the edge of the Petri dish 99%, respectively). To confirm this result, we and they were cultured at room temperature: observed and described their detailed morpho- 20 2 25 C[9]. The observations were performed for logical features. 7 2 14 days. The colors were standardized using Munsell colors [15]. We photographed the colonies 3.2. Taxonomy using NEX-5R digital camera (Sony, Tokyo, Japan). The microscopic characters were observed from 3% Trichoderma afroharzianum P. Chaverri, F.B. KOH mounts with Olympus BX51 light microscope Rocha, Degenkolb & I. Druzhinina, Mycologia (Olympus, Tokyo, Japan). Olympus DP20 micro- 107(3): 580 (2014) (Figure 2). scopic camera (Olympus, Tokyo, Japan) was used to Colony on CMD, aerial mycelium abundant; cot- take pictures of conidiophore and conidia. More tony conidia typically abundant in aerial mycelium, MYCOBIOLOGY 179 Figure 1. The 50% majority-rule consensus tree which contains 29 taxa and 686 characters obtained from the Bayesian ana- lysis based on EF1a Numbers above branches indicate posterior probabilities. Fungal cultures collected in this study are in à bold. Sequences of type specimens are indicated by asterisk symbols ( ). dark olive green (5GY3/4) to light olive green Han River, February 19 2014, Seokyoon Jang (5GY5/4) colored; olive (5Y4/3) pigment diffused. (KUC21213, NIBRFGC000501544, Genbank Acc. On PDA aerial mycelium abundant, cottony, radi- No. KX912217; KUC21214, NIBRFGC000501545, ating; conidia abundant and disposed in concentric Genbank Acc.