Fruit rot is one of the most important diseases affecting watermelon (Citrullus lanatus). This disease has been associated with substantial economic losses. In May 2022, fruit rot on watermelons was found during the post-harvest storage phase in local markets located in Chiang Mai Province, Thailand. The causal fungi were isolated from lesions and identified as Lasiodiplodia theobromae based on morphological characteristics and a phylogenetic analysis of combined sequences of the internal transcribed spacer (ITS) of ribosomal DNA, beta-tubulin (tub), RNA polymerase II subunit (rpb2), and the translation elongation factor 1-alpha (tef1-alpha) genes. Subsequently, pathogenicity tests were conducted and the results showed that the isolated fungi caused symptoms of fruit rot in inoculated fruit specimens. This result was consistent with symptoms that were observed in local markets. This is the first report of post-harvest fruit rot on watermelons caused by L. theobromae in Thailand.

Guava (Psidium guajava L.) is a popular fruit crop that is widely cultivated in Thailand. In November 2023, brown spot disease on guava was observed during postharvest storage at 22 to 31°C and 70 to 75% relative humidity over a period of 3 to 7 days in Fang District, Chiang Mai Province, Thailand. The disease incidence was ~20% of 100 fruits per pallet box. The disease severity on each fruit ranged from 40 to 70% of the surface area affected by lesions. The symptoms appeared as circular to irregular brown to dark brown spots, ranging from 5 to 30 mm in diameter. Fungi were isolated from lesions using a single conidial isolation method (Choi et al. 1999). Two fungal isolates (SDBR-CMU497 and SDBR-CMU498) with similar morphology were obtained. Colonies on potato dextrose agar (PDA) and malt extract agar (MEA) were 65 to 67 and 29 to 38 mm in diameter, respectively after incubation for 1 week at 25°C. Colonies on PDA and MEA were flat, slightly undulate, greenish gray in the center, greyish green at the margin; reverse black. Both isolates produced asexual structures. Pycnidia were black, granular, and grouped. Conidiogenous cells were hyaline, subcylindrical to cylindrical, 8.5 to 17.5 × 3 to 5.5 µm. Conidia were single-celled, hyaline, obovoid to ellipsoid, 5.2 to 9.4 × 3.6 to 7.5 µm (n = 50), smooth-walled, with a single apical appendage. Morphologically, both isolates resembled Phyllosticta capitalensis (Wikee et al. 2013). The internal transcribed spacer (ITS) region, large subunit (nrLSU), translation elongation factor 1-alpha (tef1-α), actin (act), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) genes were amplified using primer pairs ITS5/ITS4, LROR/LRO5, EF1-728F/EF2, ACT-512F/ACT-783R, and GPD1-LM/GPD2-LM, respectively (White et al. 1990; Zhang et al. 2022). Sequences were deposited in GenBank (ITS: PP946770, PP946771; nrLSU: PP948677, PP948678; tef1-α: PP948012, PP948013; act: PP948014, PP948015; GAPDH: PP948016, PP948017). Maximum likelihood phylogenetic analyses of the concatenated five genes identified both isolates as P. capitalensis. Thus, both morphology and molecular data confirmed the fungus as P. capitalensis. To confirm pathogenicity, healthy commercial guava fruits cultivar Kim Ju were surface disinfected by 0.1% NaClO for 3 min, rinsed three times with sterile distilled water, and wounded (Cruz-Lagunas et al. 2023). Conidia were collected from 2-week-old cultures on PDA and suspended in sterile distilled water. Fifteen microliters of a 1 × 106 conidia/ml suspension were dropped onto the wounded fruits. Mock inoculations were used as a control with sterile distilled water. Ten replications were conducted for each treatment and repeated twice. The inoculated fruits were stored in individual sterile plastic boxes at 25°C with 80 to 90% relative humidity. After 7 days, all inoculated fruits exhibited brown to dark brown lesions, while control fruits were asymptomatic. Phyllosticta capitalensis was consistently reisolated from the inoculated tissues on PDA to complete Koch's postulates. Prior to this study, P. capitalensis was known to cause brown or black spot disease on guava fruits cultivated in fields in China (Liao et al. 2020), Egypt (Arafat 2018), and Mexico (Cruz-Lagunas et al. 2023). To our knowledge, this is the first report of P. capitalensis causing postharvest brown spot disease on guava fruit in Thailand. The results will inform epidemiological investigations and future approaches to managing this disease.

A significant global problem affecting muskmelon (Cucumis melo L.) is fruit rot caused by phytopathogenic fungi, which results in unsaleable products and substantial financial losses. In 2022 and 2023, fruit rot on muskmelon was found during the postharvest storage period in Phayao Province of northern Thailand. The aim of the current study was to isolate the species of fungi causing the fruit rot lesions. Out of the rot lesions on muskmelons, nine fungal isolates were received. All isolates of fungi were identified through a combination of morphological characteristics and molecular analyses. Based on their morphological traits, all isolated fungal isolate was assigned to the genus Fusarium. All the fungal isolates were determined to belong to the Fusarium incarnatum-equiseti species complex through multi-gene phylogenetic analysis employing the calmodulin (cam), RNA polymerase second largest subunit (rpb2), and translation elongation factor 1-alpha (tef1-α) genes. These isolates were identified as F. compactum (SDBR-CMU483), F. jinanense (SDBR-CMU484, SDBR-CMU485, and SDBR-CMU486), F. mianyangense (SDBR-CMU487 and SDBR-CMU488), and F. sulawesiense (SDBR-CMU489, SDBR-CMU490, and SDBR-CMU491). Moreover, pathogenicity tests were subsequently carried out, and the results indicated that all fungal isolates caused symptoms of fruit rot on inoculated muskmelon fruits. Notably, this result was consistent with the symptoms observed throughout the postharvest storage period. In the fungicide screening test, all fungal isolates showed sensitivity to copper oxychloride. However, all isolates showed insensitivity to benalaxyl-M + mancozeb, carbendazim, mancozeb, and metalaxy. To the best of our knowledge, the present study is the first to identify F. compactum, F. jinanense, and F. mianyangense as new causative agents of muskmelon fruit rot in Thailand and other regions globally. This is also the first report of postharvest fruit rot on muskmelons caused by F. sulawesiense in Thailand. Furthermore, the fungicide screening results indicate that fungicide resistance can be beneficial in developing potential management strategies against postharvest fruit rot disease of muskmelon caused by these four pathogenic Fusarium species.

Jackfruit (Artocarpus heterophyllus Lam.) is commonly grown in Thailand. In June 2023, leaf anthracnose on this plant was observed at a field in Chai Prakan District (19°42'24"N, 99°01'59"E), Chiang Mai Province, Thailand, with ~25% disease incidence in a 1000-m2 plantation area. The initial symptom had brown spots with a yellow halo, enlarged, elongated, 0.2 to 2 cm in diameter, irregular, sunken, brown, with a dark brown halo, and leaves withered and dried. Pale yellow conidiomata developed on the lesions in high humidity. Ten symptomatic leaves were used to isolate the fungal causal agents through a single spore isolation method (Tovar-Pedraza et al. 2020). Four fungal isolates (SDBR-CMU492 to SDBR-CMU495) with similar morphology were obtained. Colonies on potato dextrose agar (PDA) were 70 to 85 mm in diameter, white to grayish white with cottony mycelia, the reverse pale yellow after incubation at 25°C for 1 week. All isolates produced asexual structures. Setae were brown with 1 to 3 septa, 40 to 100 × 2.2 to 4.0 µm, a cylindrical base, and acuminate tip. Conidiophores were hyaline to pale brown, septate, and branched. Conidiogenous cells were hyaline to pale brown, cylindrical to ampulliform, 7.4 to 27.2 × 2.0 to 4.5 µm. Conidia were one celled, hyaline, smooth walled, cylindrical, ends rounded, guttulate, 11.1 to 15.7 × 3.4 to 6.1 µm. Appressoria were dark brown to black, oval to irregular, 8.8 to 24.9 × 3.6 to 10 µm. Morphologically, all isolates resembled the Colletotrichum gloeosporioides species complex (Weir et al. 2012). The internal transcribed spacer (ITS) region, actin (act), β-tubulin (tub2), calmodulin (CAL), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) genes were amplified using primer pairs ITS5/ITS4, ACT-512F/ACT-783R, T1/T22, CL1C/CL2C, and GDF1/GDR1, respectively (White et al. 1990; Weir et al. 2012). Sequences were deposited in GenBank (ITS: PP068858, PP068859, PP446789, PP446790; act: PP079636, PP079637, PP460760, PP460761; tub2: PP079638, PP079639, PP460762, PP460763; CAL: PP079634, PP079635, PP460758, PP460759; GAPDH: PP079632, PP079633, PP460756, PP460757). Maximum likelihood phylogenetic analyses of the concatenated five genes identified all isolates as C. siamense. To pathogenicity test, the mature leaves of a healthy plant were surface disinfested using 0.1% NaClO for 3 min, rinsed three times with sterile water, and wounded. Conidia suspensions (15 µl of 1 × 106 conidia/ml) of each isolate grown on PDA at 25°C for 2 weeks were used to inoculate wounded and unwounded samples by the attached method. Control leaves were mock inoculated with sterile distilled water. Ten replications were conducted for each treatment and repeated twice. Plants were placed in a greenhouse at 25 to 30°C and 80 to 90% relative humidity. After 7 days, all inoculated leaves displayed brown lesions, while control leaves had no symptoms. Colletotrichum siamense was reisolated from inoculated tissues on PDA to complete Koch's postulates. Prior to this study, C. fructicola and C. gloeosporioides caused leaf anthracnose on jackfruit worldwide (Sangchote et al. 2003; Chitambar 2016). Leaf anthracnose on jackfruit caused by C. siamense has been reported from Australia (James et al. 2014) and Bazil (Borges et al. 2023). In Thailand, Bhunjun et al. (2019) reported that C. artocarpicola causes leaf anthracnose in jackfruit. Therefore, this is first report of C. siamense causing leaf anthracnose on jackfruit in Thailand. The finding will inform epidemiological investigations and future approaches to managing this disease.

The genus Cladophialophora was established in 1980. Prior to this study, a total of 63 species had been validated and assigned to this genus. The members of Cladophialophora have been recognized as human pathogens that cause chromoblastomycosis and various other skin diseases. Beyond its pathogenic role, some members of this genus are associated with a range of lifestyles, as phytopathogens, endophytic fungi, saprobic fungi, rock-inhabiting fungi, and lichenicolous fungi. In this study, we present background information and recent research progress regarding the genus Cladophialophora by elucidating its taxonomic history, species diversity, classification outline, ecology, and geographical distribution. Additionally, the phylogenetic placement of the members of this genus has been updated based on multi-gene phylogenetic analyses. Moreover, the issues and perspectives in this genus are summarized. This article provides researchers with valuable information and increases the understanding of Cladophialophora, which will be useful for further research (taxonomy, phylogeny, distribution, diversity, ecological roles and medical fields) in this genus.

A new edible wild mushroom species, described herein as Panus sribuabanensis, was collected from local markets and natural forests located in northern Thailand. This species is characterized by its medium to large-sized basidiomata, broadly ellipsoid to ellipsoid-shaped basidiospores, dimitic hyphal system, and the absence of hyphal pegs. A molecular phylogenetic analysis of combined the internal transcribed spacer (ITS) and large subunit (nrLSU) of nuclear ribosomal DNA sequences supported the monophyly of P. sribuabanensis as a distinct lineage within the genus Panus. Full description, illustrations, color photographs, and a phylogenetic tree to show the placement of P. sribuabanensis are provided. The dried mushroom showed a nutritional composition within the range of 2.58%-2.67% for fat content, 27.10%-27.98% for protein, and 43.97%-44.10% for carbohydrates. The ethanolic extracts from this mushroom exhibited a total phenolic content ranging from 0.66 to 0.74 mg GAE/g dry weight (dw). Moreover, the antioxidant activities of ethanolic extracts evaluated by the 2,2-diphenyl-1-picrylhydrazyl (0.90-1.08 mg TE/g dw) and ferric reducing antioxidant power (0.93-1.08 mg TE/g dw) assays demonstrate higher activity compared to the 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) assay (0.44-0.51 mg TE/g dw). The outcomes of this study provide significant information on the nutritional value, phenolic content, and antioxidant activity potential of this new mushroom species discovered in northern Thailand.

Most species of Dothiora are known from the dead parts of various host plants as saprobic fungi in terrestrial habitats occurring in tropical and temperate regions. In the present study, samples of Dothiora were collected from dead twigs and branches of Capparis spinosa, Rhaponticum repens, and an unknown angiosperm plant from the Tashkent and Jizzakh regions of Uzbekistan. Multi-gene phylogenetic analyses based on a combined ITS, LSU, SSU, TEF1, and TUB2 sequence data revealed their taxonomic positions within the Dothideaceae. Three new species of Dothiora, namely, Dothiora capparis, Dothiora rhapontici, and Dothiora uzbekistanica were proposed by molecular and morphological data. Likewise, the phylogenetic relationship and morphology of Dothiora are discussed. In addition, we provide a list of accepted Dothiora species, including host information, distribution, morphology descriptions, and availability of sequence data, to enhance the current knowledge of the diversity within Dothiora.

The genus Collybiopsis is known to be found in tropical and temperate regions throughout the world. Currently, 66 species have been validated and assigned to this genus. In this study, we have updated a brief review of the genus Collybiopsis through an overview of species diversity, geographic distribution, and recently published literature. Prior to this study, only four Collybiopsis species have been reported from Thailand. During surveys of macrofungi in northern and southern Thailand from 2018 to 2022, nine Collybiopsis specimens were collected. These nine specimens were identified as belonging to five species, namely C. gibbosa, C. indocta, C. melanopus, C. menehune, and C. nonnulla based on morphological characteristics and molecular data of the internal transcribed spacer (ITS) and large subunit (nrLSU) of nuclear ribosomal DNA sequences. The present study offers the first record of these five Collybiopsis species in Thailand. Detailed morphological descriptions, photographs, illustrations, comparisons with related taxa, and a phylogenetic tree to show the placement of these five species from Thai specimens are provided. Moreover, a new key to the species of Collybiopsis found in Thailand is presented.

Peacock plant (Calathea orbifolia (Linden) H.A.Kenn.) is cultivated as a valuable houseplant in China. In September 2024, leaf blight was found on this plant in a field located in Shenzhen (22°35'55"N, 113°59'21"E), Guangdong Province, China. The area investigated was ~900 m2. The disease incidence was ~70% of 100 plants. Initial symptoms of brown spots appeared on leaves, gradually becoming enlarged, elongated, 0.5 to 10 × 0.2 to 4.5 cm, irregular, dark brown, with a yellow halo, and leaves blighted and desiccated. Ten symptomatic leaves were collected for pathogen isolation. Leaf pieces (5×5 mm2) of lesion margins were surface disinfected with 1% NaClO for 1 min, 70% ethanol for 30 s, rinsed in sterile distilled water, placed on PDA, and incubated at 25°C. After 3 days, fungal colonies were purified by a single hyphal tip method on PDA. Three isolates (MBSZU 24-001 to MBSZU 24-003) with similar morphology were obtained. Colonies on PDA were 48 to 54 mm in diameter after 1 week at 25°C, then gray, flat with entire edges, aerial mycelia dense, and dark in the center and gray at the margin on the reverse side after 2 weeks. Conidiophores were olivaceous-brown, cylindrical, septate, unbranched, up to 230 × 3.4 to 5 µm. Conidiogenous cells were integrated, straight to curved, proliferating sympodial, 25 to 60 × 4.5 to 7 µm. Conidia were straight to slightly curved, ellipsoid, pale olivaceous brown to dark olivaceous brown, 2-6-distoseptate, with a distinct basal hilum, 26.9 to 70 × 11.4 to 21.6 µm (n = 50). Morphological characteristics of all isolates resembled the Exserohilum (Hernández-Restrepo et al. 2018). The internal transcribed spacer (ITS) region, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and translation elongation factor 1-alpha (tef1-α) genes were amplified using primer pairs ITS5/ITS4 (White et al. 1990), GPD1/GPD2 (Berbee et al. 1999), and EF1-983F/EF1-2218R (Rehner and Buckley 2005), respectively. Sequences were deposited in GenBank (ITS: PQ498876 to PQ498878; GAPDH: PQ509760 to PQ509762; tef1-α: PQ509763 to PQ509765). In the BLAST analysis, the ITS, GAPDH, and tef1-α sequences showed 99.50% (599 bp out of 602 bp), 98.89% (536 bp out of 542 bp), and 99.78% (926 bp out of 928 bp), respectively, to E. rostratum (CBS 325.87). Maximum likelihood and Bayesian inference phylogenetic analyses of the concatenated three genes identified all isolates as E. rostratum. To test pathogenicity, both wounded and unwounded healthy leaves were used in this experiment. All leaves were wiped with 0.1% NaClO and then rinsed three times with sterile water. Conidia suspensions (15 µl of 1 × 106 conidia/ml) of each isolate grown on PDA at 25°C for 3 weeks were placed on all samples using the attached leaf assay. Control leaves were mock-inoculated with sterile distilled water. Ten replications were conducted for each treatment and repeated twice. Plants were incubated at 25°C with 80 to 85% relative humidity. After 10 days, all inoculated leaves had brown lesions with yellow halos, while control leaves remained asymptomatic. E. rostratum was consistently reisolated from the lesions on PDA to complete Koch's postulates. Prior to this study, E. rostratum was identified as a causal agent of leaf blight on Calathea picturata in China (Taiwan, Chern et al. 2011). This is the first report of leaf blight caused by E. rostratum on C. orbifolia in China and worldwide. These findings will provide insights for epidemiological investigations and future approaches to managing this disease.

A new species of soil fungi, described herein as Penicillium thailandense, was isolated from soil samples of deciduous dipterocarp forest in Lamphun Province, Thailand. This species was identified by using combination of morphological characteristics and molecular analyses. Morphologically, P. thailandense is similar to P. sanjayi, but it can be distinguished by having monoverticillate and biverticillate conidiophores, white to dark gray sclerotia, and larger conidia. Multi-gene phylogenetic analyses of a combination of the internal transcribed spacer (ITS) of ribosomal DNA, β-tubulin (BenA), calmodulin (CaM), and RNA polymerase II second largest subunit (rpb2) genes revealed that P. thailandense belongs to the Penicillium section Citrina and is distinct from other known species. This paper provides a description, illustrations, and phylogenetic tree of this novel species.

The rose apple (Syzygium samarangense (Blume) Merr. & L.M.Perry) plant has been commonly cultivated in Thailand. In May of 2022, leaf spot disease of rose apple was discovered in Chiang Mai Province, Thailand, with approximately 30% disease incidence. The typical symptoms initially showed brown spots (0.1 to 0.5 mm in diameter) with a yellow halo surrounding. These spots then expanded with black edges and the infected leaves appear blighted and desiccated. In humid conditions, pale yellow conidiomata formed on the lesions. Small pieces (5 × 5 mm2) of the margins between lesions and the healthy tissue were surface disinfected with 1% NaClO for 1 min, 70% ethanol for 30 s, and washed three times with sterile distilled water. Tissues were placed on potato dextrose agar (PDA) and incubated at 25 ºC for three days. Three fungal isolates (SDBR-CMU419, SDBR-CMU420, and SDBR-CMU421) were obtained that exhibited similar morphology. Fungal colonies appeared white to gray with cottony mycelia after incubation on PDA at 25 ºC for one week. All fungal isolates produced asexual morph on PDA. Setae were 5590 × 2.53.5 µm, brown with 13-septa, cylindrical base, and tip rounded. Conidiophores were hyaline to pale brown, septate, and branched. Conidiogenous cells were hyaline to pale brown, cylindrical to ampulliform, 2050 µm long (n = 50). Conidia were one-celled, hyaline, smooth-walled, aseptate, straight, cylindrical, end round, guttulate, 1017 × 35 µm (n = 50). Appressoria were mostly formed from mycelia, oval to irregular, brown to dark brown, smooth-walled, 610 × 57 µm (n = 50). Morphologically, all fungal isolates resembled to Colletotrichum (Weir et al. 2012; Jayawardena et al. 2021). The internal transcribed spacer (ITS) region of the ribosomal DNA, actin (act), β-tubulin (tub2), calmodulin (CAL), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) were amplified using primer pairs ITS5/ITS4 (White et al. 1990), ACT-512F/ACT-783R (Carbone and Kohn 1999), T1/T22 (O'Donnell and Cigelnik 1997), CL1C/CL2C (Weir et al. 2012), and GDF1/GDR1 (Templeton et al. 1992), respectively. The ITS (ON740892 to ON740894), act (ON759242 to ON759244), tub2 (ON759245 to ON759247), CAL (ON759248 to ON759250), and GAPDH (ON759251 to ON759253) sequences were deposited in GenBank. Multi-gene (combined data set of ITS, GAPDH, CAL, act, and tub2) maximum phylogenetic analyses indicated that all fungal isolates clustered with C. siamense ICMP 18578 (type strain) with strong statistical (99% ML) support. For pathogenicity test, asymptomatic leaves, stems and fruits detached from healthy plants were surface disinfected using 0.1% NaClO for 3 min, washed three times with sterile distilled water, and air-dried. A uniform wound (3 pores, 1 mm in width) was made at the equator of each leaf, stem and fruit using aseptic needles. Mycelial plugs (5 mm in diameter) and conidia suspensions (1 × 106 conidia/ml) of each fungal isolate grown on PDA at 25 ºC for one week were used to inoculate both wounded and unwounded samples by the detached method (Huda‑Shakirah et al. 2022; Suwannarach et al. 2022). Plugs of PDA and sterile distilled water were used as controls. Ten replications were performed for each treatment and the experiment was repeated twice. All inoculated samples were incubated in a moist chamber at 25 ºC with 90% relative humidity. The disease severity index was used to evaluate the specimens (Acar et al. 2008; Ngegba et al. 2017). After one week, both wounded and unwounded leaves that inoculated with mycelial plugs and conidia suspensions showed brown leaf spots and a weak infection. Mycelial plugs inoculated on both wounded and unwounded fruits revealed a moderate infection, but inoculation of conidia suspensions showed a weak infection. No symptoms of disease were observed on the inoculated stems. Control leaves, stems and fruits remained asymptomatic. The pathogen C. siamense was re-isolated from spot and rot lesions on PDA in order to fulfill Koch's postulates. Phoulivong et al. (2012) reported that C. siamense is a causal agent of fruit rot in rose apples cultivated in Lao and Thailand. To our knowledge, this is the first report of C. siamense causing leaf spots on rose apple plants in Thailand. Importantly, these findings will provide crucial information for epidemiologic studies and in the development of appropriate management strategies for this newly emerging disease.

A new endophytic ascomycete, described herein as Fusarium endophyticum, was isolated from leaves of Camellia sinensis var. assamica collected from Nan Province, northern Thailand. This species is described using morphological characteristics and molecular multi-gene analyses. Multi-gene phylogenetic analyses of a combination of internal transcribed spacer region of the rDNA (ITS), translation-elongation factor 1 alpha (tef-1), RNA polymerase II second largest subunit (rpb2), and RNA polymerase II largest subunit (rpb1) genes revealed that F. endophyticum belonged to the Fusarium lateritium species complex (FLSC) and was distinct from all other known species. A full description, illustrations and a phylogenetic tree showing the position of F. endophyticum are provided.

This article is the 14th in the Fungal Diversity Notes series, wherein we report 98 taxa distributed in two phyla, seven classes, 26 orders and 50 families which are described and illustrated. Taxa in this study were collected from Australia, Brazil, Burkina Faso, Chile, China, Cyprus, Egypt, France, French Guiana, India, Indonesia, Italy, Laos, Mexico, Russia, Sri Lanka, Thailand, and Vietnam. There are 59 new taxa, 39 new hosts and new geographical distributions with one new combination. The 59 new species comprise Angustimassarina kunmingense, Asterina lopi, Asterina brigadeirensis, Bartalinia bidenticola, Bartalinia caryotae, Buellia pruinocalcarea, Coltricia insularis, Colletotrichum flexuosum, Colletotrichum thasutense, Coniochaeta caraganae, Coniothyrium yuccicola, Dematipyriforma aquatic, Dematipyriforma globispora, Dematipyriforma nilotica, Distoseptispora bambusicola, Fulvifomes jawadhuvensis, Fulvifomes malaiyanurensis, Fulvifomes thiruvannamalaiensis, Fusarium purpurea, Gerronema atrovirens, Gerronema flavum, Gerronema keralense, Gerronema kuruvense, Grammothele taiwanensis, Hongkongmyces changchunensis, Hypoxylon inaequale, Kirschsteiniothelia acutisporum, Kirschsteiniothelia crustaceum, Kirschsteiniothelia extensum, Kirschsteiniothelia septemseptatum, Kirschsteiniothelia spatiosum, Lecanora immersocalcarea, Lepiota subthailandica, Lindgomyces guizhouensis, Marthe asmius pallidoaurantiacus, Marasmius tangerinus, Neovaginatispora mangiferae, Pararamichloridium aquisubtropicum, Pestalotiopsis piraubensis, Phacidium chinaum, Phaeoisaria goiasensis, Phaeoseptum thailandicum, Pleurothecium aquisubtropicum, Pseudocercospora vernoniae, Pyrenophora verruculosa, Rhachomyces cruralis, Rhachomyces hyperommae, Rhachomyces magrinii, Rhachomyces platyprosophi, Rhizomarasmius cunninghamietorum, Skeletocutis cangshanensis, Skeletocutis subchrysella, Sporisorium anadelphiae-leptocomae, Tetraploa dashaoensis, Tomentella exiguelata, Tomentella fuscoaraneosa, Tricholomopsis lechatii, Vaginatispora flavispora and Wetmoreana blastidiocalcarea. The new combination is Torula sundara. The 39 new records on hosts and geographical distribution comprise Apiospora guiyangensis, Aplosporella artocarpi, Ascochyta medicaginicola, Astrocystis bambusicola, Athelia rolfsii, Bambusicola bambusae, Bipolaris luttrellii, Botryosphaeria dothidea, Chlorophyllum squamulosum, Colletotrichum aeschynomenes, Colletotrichum pandanicola, Coprinopsis cinerea, Corylicola italica, Curvularia alcornii, Curvularia senegalensis, Diaporthe foeniculina, Diaporthe longicolla, Diaporthe phaseolorum, Diatrypella quercina, Fusarium brachygibbosum, Helicoma aquaticum, Lepiota metulispora, Lepiota pongduadensis, Lepiota subvenenata, Melanconiella meridionalis, Monotosporella erecta, Nodulosphaeria digitalis, Palmiascoma gregariascomum, Periconia byssoides, Periconia cortaderiae, Pleopunctum ellipsoideum, Psilocybe keralensis, Scedosporium apiospermum, Scedosporium dehoogii, Scedosporium marina, Spegazzinia deightonii, Torula fici, Wiesneriomyces laurinus and Xylaria venosula. All these taxa are supported by morphological and multigene phylogenetic analyses. This article allows the researchers to publish fungal collections which areimportant for future studies. An updated, accurate and timely report of fungus-host and fungus-geography is important. We also provide an updated list of fungal taxa published in the previous fungal diversity notes. In this list, erroneous taxa and synonyms are marked and corrected accordingly.

Diaporthe is a large and taxonomically complex genus, with over a thousand epithets listed in Index Fungorum. The placement of many Diaporthe species remains confusing, and there is a lack of consensus on their taxonomy and phylogeny. In this study, we provide annotated notes on accepted or presumed species of Diaporthe up to 2023. Our notes cover 832 species and include information on their morphology, ecology, geographic distribution, molecular data, and pathogenicity, where available. Diaporthe cyatheae comb. nov., D. pseudobauhiniae nom. nov., D. xishuangbannaensis nom. nov., D. krabiensis sp. nov., and D. pseudobiguttulata nom. nov. are introduced in this paper. In addition, we list 331 species that were previously classified as Diaporthe but are no longer accepted as members of the genus. Our comprehensive review of Diaporthe species provides a resource for researchers and taxonomists, enabling accurate identification and classification, and enhancing our understanding ecological roles of these fungi.

A new macro-fungal species, described herein as Hymenagaricus siamensis, was collected from northern Thailand during the period from 2020 to 2022. This species is characterized by its small-sized basidiomata, a squamulose pileipellis consisting of pseudoparenchymatous tissue, yellowish-brown basidiospores and an absence of pleurocystidia and clamp connections. However, it is clearly distinguishable from H. nigroviolaceus by the presence of larger basidiospores and smaller pseudoparenchymatous cells in the squamulose pileus. Phylogenetic analysis of internal transcribed spacers (ITS) and large subunit (nrLSU) of the nuclear ribosomal DNA (rDNA) also revealed that the position of H. siamensis is well-supported within the genus Hymenagaricus, but distinct from other sequenced species. A full description, color photographs, illustrations and a phylogenetic tree showing the position of H. siamensis are provided. Comparisons between morphologically similar and related species have also been made and are discussed.

Fruit rot caused by phytopathogenic fungi is one of the major diseases affecting watermelons (Citrullus lanatus) around the world, which can result in unmarketable fruits and significant economic losses. Fruit rot was observed on watermelons throughout the postharvest storage periods in Phayao Province, northern Thailand in 2022. For the present study, a total of ten fungal isolates were isolated from the rot lesions of watermelons. All obtained fungal isolates were then characterized in terms of their pathogenicity. The results indicated that only four fungal isolates caused rot disease with similar symptoms during the postharvest storage period. Based on their morphological characteristics, these four fungal isolates were identified as belonging to the genus Fusarium. Using multi-gene phylogenetic analyses with a combination of the translation elongation factor 1-alpha (tef-1), calmodulin (cam), and RNA polymerase second largest subunit (rpb2) genes, the fungal isolates were subsequently identified as Fusarium compactum and F. paranaense. Taken together, the results of this study indicate that F. compactum and F. paranaense cause fruit rot disease in watermelons. To the best of our knowledge, this is the first study to report F. compactum and F. paranaense as novel pathogens of watermelon fruit rot both in Thailand and elsewhere in the world.

A new species of rock-inhabiting fungi, described herein as Anteaglonium saxicola, was isolated from rock samples collected from natural forests in Lamphun Province, Thailand. This species was introduced based on morphological characteristics and multi-gene phylogenetic analyses. Multi-gene phylogenetic analyses based on a combination of the 28S large subunit (nrLSU), 18S small subunit (nrSSU), and internal transcribed spacer (ITS) of the nuclear ribosomal DNA (rDNA) along with the translation elongation factor (tef1-α) genes revealed that A. saxicola belongs to the clade of the genus Anteaglonium and is clearly distinct from other known Anteaglonium species. This paper provides a description, illustrations, and phylogenetic position of this novel species.

Giant philodendron (Philodendron giganteum Schott) is cultivated in Thailand and has become an important ornamental houseplant with great economic value. During the rainy season in July 2022, anthracnose disease on this plant was observed at a nursery in Saraphi District, Chiang Mai Province (18°40'18" N, 99°03'17" E), Thailand. The area investigated was approximately 800 m². The disease incidence was estimated at above 15% according to the total number of plants (220 plants). The disease severity of each plant was between 25 and 50% of the necrotic lesion on the leaf. Initially, symptoms with brown spots, appeared on leaves, gradually becoming enlarged, elongate, 1 to 11 cm long by 0.3 to 3.5 cm wide, irregular, sunken, dark brown, with a yellow halo surrounding each lesion. Then, the diseased leaves eventually withered and died. Leaf pieces (5 × 5 mm2) of the margins between lesions and the healthy tissue were surface sterilized in 1% NaClO for 1 min, 70% ethanol for 30 s, and rinsed three times with sterile distilled water. Tissues were placed on potato dextrose agar (PDA) and incubated at 25°C in darkness. After three days of incubation, pure fungal colonies were purified by a single hyphal tip method on PDA (Korhonen and Hintikka 1980). Two fungal isolates (SDBR-CMU471 and SDBR-CMU472) with similar morphology were obtained. Fungal colonies on PDA were white and 38 to 40 mm in diameter after 3 days of incubation at 25 °C, then grayish white with cottony mycelia, the reverse side pale yellow after one week of incubation. Both isolates produced asexual structures on PDA. Setae were brown with 1 to 3 septa, 50 to 110 × 2.4 to 4.0 µm, with a cylindrical base, and acuminate tip. Conidiophores were hyaline to pale brown, septate, and branched. Conidiogenous cells were hyaline to pale brown, cylindrical to ampulliform, 9.5 to 35 µm long (n = 50). Conidia were single-celled, straight, hyaline, smooth-walled, cylindrical, ends rounded, guttulate, 9.1 to 19.6 × 3.5 to 5.6 µm (n = 50). Appressoria were brown to dark brown, oval to irregular, smooth-walled, 5 to 10 × 5 to 7.5 µm (n = 50). Morphologically, both fungal isolates resembled members of the Colletotrichum gloeosporioides species complex (Weir et al. 2012; Jayawardena et al. 2021). The internal transcribed spacer (ITS) region of the ribosomal DNA, actin (act), β-tubulin (tub2), calmodulin (CAL), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) genes were amplified using primer pairs ITS5/ITS4 (White et al. 1990), ACT-512F/ACT-783R (Carbone and Kohn 1999), T1/T22 (O'Donnell and Cigelnik 1997), CL1C/CL2C (Weir et al. 2012), and GDF1/GDR1 (Templeton et al. 1992), respectively. Sequences were deposited in GenBank (ITS: OQ699280, OQ699281; act: OQ727122, OQ727123; tub2: OQ727124, OQ727125; CAL: OQ727126, OQ727127; GAPDH: OQ727128, OQ727129). Multi-gene (combined data set of ITS, GAPDH, CAL, act, and tub2) maximum likelihood phylogenetic analyses demonstrated that both isolates were identified as C. siamense with 100% support. In a pathogenicity test, leaves of healthy plants were surface sterilized with a 0.1% NaClO solution for 3 min, rinsed three times with sterile distilled water. After being air-dried, a uniform wound (5 pores, 3 mm in width) was made at the equator of each leaf using aseptic needles. Conidial suspensions were collected from two-week-old cultures and suspended in sterile distilled water with 0.05% Tween-20. Fifteen microliters of the conidial suspension (1 × 106 conidia/ml) were placed on wounded attached leaves. As well, wounded control leaves were mock inoculated with sterile distilled water. Ten replications were conducted for each treatment and experiments were repeated twice. The inoculated plants were stored in a greenhouse at conditions of 25 to 30°C and 75 to 85% relative humidity. After 14 days, all the inoculated leaves showed disease symptoms, brown lesions with yellow halos, whereas control leaves remained asymptomatic. The pathogen C. siamense was consistently re-isolated on PDA from the inoculated tissues to complete Koch's postulates. Colletotrichum siamense has been reported as a causal agent on a wide range of host plants in Thailand and throughout the world (Farr and Rossman 2021; Jayawardena et al. 2021). Prior to this study, C. endophytica, C. karsti, C. orchidearum, C. philodendricola, and C. pseudoboninense were identified as causal agents of anthracnose on philodendrons (Xue et al. 2020; Zhang et al. 2023). However, anthracnose caused by Colletotrichum species on giant philodendron (P. giganteum) has not been previously reported. Thus, we propose C. siamense as a new causal agent of anthracnose disease on giant philodendron. This study provides information for further investigation into the epidemiology and management of this disease. Moreover, further investigations should be carried out in other philodendron growing areas of Thailand in order to specifically search for this pathogen.

Members of the family Herpotrichiellaceae are distributed worldwide and can be found in various habitats including on insects, plants, rocks, and in the soil. They are also known to be opportunistic human pathogens. In this study, 12 strains of rock-inhabiting fungi that belong to Herpotrichiellaceae were isolated from rock samples collected from forests located in Lamphun and Sukhothai provinces of northern Thailand during the period from 2021 to 2022. On the basis of the morphological characteristics, growth temperature, and multi-gene phylogenetic analyses of a combination of the internal transcribed spacer, the large subunit, and the small subunit of ribosomal RNA, beta tubulin and the translation elongation factor 1-a genes, the new genus, Petriomyces gen. nov., has been established to accommodate the single species, Pe. obovoidisporus sp. nov. In addition, three new species of Cladophialophora have also been introduced, namely, Cl. rupestricola, Cl. sribuabanensis, and Cl. thailandensis. Descriptions, illustrations, and a phylogenetic trees indicating the placement of these new taxa are provided. Here, we provide updates and discussions on the phylogenetic placement of other fungal genera within Herpotrichiellaceae.