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Microdochium sichuanense L.S. Dissan., J.C. Kang & Maharachch., sp. nov. (FIGUER 2) Index Fungorum Number: IF900348, Facesoffungi: 14277 Etymology:— Referring to the location “ Sichuan Province ” where the fungus was collected Holotype:—KUN-HKAS127240 Saprobic on dead leaves of Poaceae in terrestrial habitats. Sexual morph: Ascomata 100–180 μm high, 60–100 μm diam. (x̅ = 146.3 × 86.9 μm, n = 5), solitary, scattered, appear as black dots on the host surface, square to ellipsoidal, brown, immersed, apapillate, ostiolate. Peridium 10–20 μm wide, evenly thickened, comprising brown cells of textura angularis to textura prismatica, flattened and hyaline towards inner layers, fused with host tissues. Hamathecium comprising hyaline, cylindrical, guttulate, branched paraphyses (2–6 μm wide), arising from base of ascomata. Asci 90–140 × 15–20 μm (x̅ = 110 × 18 μm, n = 15), unitunicate, 8-spored, overlapping 1–2 seriate, clavate to oblong, with a minute J- apical ring or without an epical ring, with a short stipe. Ascospores 10–22 × 4–7 μm (x̅ = 16 × 5.5 μm, n = 15), hyaline, oval to fusiform, sometimes allantoid, straight or slightly curved, guttulate. Asexual morph: Undetermined Culture characteristics:— Colonies on PDA reaching 2 cm diam. after 2 weeks at 20–25 °C, medium dense, circular to slightly irregular, slightly raised, cottony surface smooth, at first white, becoming light yellow when mature, without any pigmentation; reverse yellowish-white. Material examined:— China, Sichuan Province, Chengdu, University of Electronic Science and Technology premises, on dead leaves of an unidentified poaceous host, September 2021, Q Wang W30 (KUN-HKAS127240, holotype), ex-type cultures KUNCC 23–13008 Known distribution:— Sichuan Province, China Notes:— Microdochium sichuanense morphologically resembles M. graminearum and M. shilinense in having solitary, scattered, immersed, apapillate, ostiolate ascomata, textura angularis to prismatica cells in peridium, 8- spored, biseriate with short stipe asci, and hyaline, guttulate, fusiform, straight or curved ascospores. Microdochium sichuanense differs from M. graminearum and M. shilinense in having clavate to oblong asci without an apical ring and aseptate ascospores, while M. graminearum and M. shilinense have fusiform asci with apical ring and 0–3 transversely septate ascospores. Multi-gene phylogenetic analyses (FIGURE 1) show that our collection forms a sister group with the isolates of M. hainanense (SAUCC 210781 and SAUCC 210782) with 60% ML and 0.96 BYPP. It is impossible to compare M. sichuanense and M.hainanense as they occur in different morphs (sexual and asexual). A pairwise nucleotide comparison between the two species showed that M. sichuanense differs from M. hainanense (SAUCC 210782) in 35/566 bp of ITS (6.18%) and 150/797 bp of rpb2 (18.82%). Interestingly, both species were collected from the same host family (Poaceae), but from different locations in China (M. sichuanense: Sichuan Province and M. hainanense: Hainan Province)., Published as part of Dissanayake, Lakmali S., Kang, Ji-Chuan & Maharachchikumbura, Sajeewa S. N., 2023, Microdochium sichuanense sp. nov. (Microdochiaceae, Xylariales), from a Poaceae host in Sichuan, China, pp. 206-216 in Phytotaxa 600 (3) on pages 211-212, DOI: 10.11646/phytotaxa.600.3.7, http://zenodo.org/record/8080903

A novel mycovirus was identified infecting the phytopathogenic fungus Microdochium albescens. The characterized dsRNA segment, corresponding to the replicative intermediate of the mitovirus genome, is 2,562 base pairs (bp) in length, with an A+U content of 62.3%. A single open reading frame (ORF) was identified, encoding a putative RNA-dependent RNA polymerase (RdRp) of 706 amino acids. Phylogenetic analysis showed that this virus should be classified as a member of a new species in the genus Mitovirus, family Mitoviridae, for which we propose the name "Mitovirus gaucho". This is the first report of a mycovirus infecting the phytopathogenic fungus M. albescens, the causative agent of leaf scald on rice in Brazil.

Soilborne Rhizoctonia, Microdochium, and Fusarium species are major causal agents of seedling and stem-base diseases of wheat. Currently, seed treatments are considered the most effective solution for their control. Rhizoctonia solani anastomosis groups (AGs) 2-1 and 5, R. cerealis, Microdochium, and Fusarium spp., were used in series of field experiments to determine their capability to cause soilborne and stem-base disease and to quantify their comparative losses in the establishment and yield of wheat. The effectiveness and response to seed treatment formulated with 10 g sedaxane and 5 g fludioxonil 100 kg−1 against these soilborne pathogens were also determined. Our results showed that damping-off caused by soilborne R. cerealis was associated with significant reductions in the emergence and establishment, resulting in stunted growth and low plant numbers. The pathogen also caused sharp eyespot associated with reductions in the ear partitioning index. R. solani AG 2-1 and AG 5 were weakly pathogenic and failed to cause significant damping-off, root rot, and stem-base disease in wheat. Fusarium graminearum and F. culmorum applied as soilborne inoculum failed to cause severe disease. Microdochium spp. caused brown foot rot disease and soilborne M. nivale reduced wheat emergence. Applications of sedaxane and fludioxonil increased plant emergence and reduced damping-off, early stem-base disease, and brown foot rot, thus providing protection against multiple soilborne pathogens. R. cerealis reduced the thousand grain weight by 3.6%, whereas seed treatment including fludioxonil and sedaxane against soilborne R. cerealis or M. nivale resulted in a 4% yield increase.

Fifty six spotted rice grain samples of four commercially cultivated rice varieties namely BRRI 28, 29, Kalijira and Pajam were collected from 14 different districts of Bangladesh. Forty rice samples (Hybrid 2,3,4, BR7,11,12,14,16,22,23,25,26and BRRI28 to BRRI 55) were also collected from Bangladesh Rice Research Institute at Joydevpur. Twenty-fivespecies of fungi belonging to 15 genera were associated with these rice varieties. The isolated fungi were Alternaria alternata, Aspergillus clavatus, A. flavus, A. fumigatus, A.niger, A. ochraceus, A.oryzae, A. terreus, Chaetomium globosum, Cladosporium cladosporioides, Colletotrichum gloeosporioides, Curvularia lunata, C. lunata var. aeria, Drechslera oryzae, Fusarium moniliforme, F. oxysporum, F. solani, Microdochium oryzae, Nigrospora oryzae, Penicillium spp., Pestalotiopsis guepinii, Sarocladium oryzae and Trichoderma viride. Amongst these fungi nine i.e. Alternaria alternata (Fr.) Keissler, Aspergillus flavus Link, Curvularia lunata (Wakker) Boedijn, Drechsler aoryzae Breda de Haan (Subramanian and Jain), Fusarium moniliforme Sheldon, F. solani (Mart.) Sacc., Microdochium oryzae (Hashloka and Yokogi) Sam. and Hal., Pestalotiopsis guepinii (Desm.) Stay. and Sarocladium oryzae (Sawada) W. Gams and D. Hawks were found to be pathogenic to rice seeds. The most predominant fungus was D. oryzae which was followed by A. flavus and the least incidence was observed in case of F. solani and P. guepinni. Bioresearch Commu. 7(1): 932-940, 2021 (January)

Microdochium chuxiongense H. Yu, W.Q. Zou & D.X. Tang, sp. nov. (Figure 2) MycoBank:— MB 844086 Etymology:— Referring to Chuxiong City where was this species collected. Typus:— The Zixi Mountains, Chuxiong City, Yunnan Province, China (25°04′19.88′′ N, 110°54′60.46′′ E, alt. 2300 m), on pileus of Bondarzewia sp., 22 September 2020, Hong Yu (YHH 20400, holotype; YFCC 8794, ex-holotype living culture). Asexual morph:— Mycelium immersed and superficial, hyphae hyaline, branched, smooth, septate, 2–3 μm wide (x̅=3 µm, n =30). Conidiophores cylindrical, straight, septate, 8–15 × 2–3 μm (x̅=11 × 2 µm, n =10), and borned from the hyphae. Conidiogenous cells sparse, solitary, clavate, occasionally curved or swollen, hyaline, smooth, septate, 27–74 × 2–3 μm (x̅=50 × 2 µm, n =20). Conidia single or multiple, long oval, shuttle or sickle, straight or curved, 0(–3)-septate, 4–12 × 2–5 μm (x̅=7 × 3 µm, n =30). Chlamydospores were produced directly from mycelium, single, round or palmate, 9–11 × 10 μm (x̅=10 × 10 µm, n =10). Sexual morph were not found. Culture characteristics:— The colony was on PDA medium fast-growing, 55–60 mm (x̅= 58 mm, n =3) in diameter after 7 days. The center has obvious milky white aerial mycelium bulge, and the edge mycelium was smooth, back light yellow. The colony was 78–82 mm (x̅= 80 mm, n =3) in diameter after 14 days, with pale aerial mycelium cottony, forming an obvious black circle in centre, back dark brown. Know distribution:— The Zixi Mountains, Chuxiong City, Yunnan Province, China. Notes:— This study reported that M. chuxiongense was isolated from pileus of Bondarzewia sp., and was different from the host reported by previous studies. Phylogenetic analysis based on four genes showed that M. chuxiongense was formed a separate clade with M. indocalami and M. maculosum, it was a sister with M. indocalami, with strongly being supported by BI posterior probabilities (PP = 83%) and ML boostrap proportions (BP = 82%). The sequence length was 3255 bp for M. indocalami and M. chuxiongense, the gap sites of M. indocalami was 293 bp, and M. chuxiongense was 759 bp, their conserved sites were 2385 bp, and variable sites were 106 bp, 73% similar to M. indocalami and M. chuxiongense. M. chuxiongense was very similar to M. indocalami in the colony, conidiophores and conidiogenous cells and conidia. However, it differed in the colony forming an obvious black circle in centre (Huang et al. 2020) (Table 2). Moreover, the shape of conidiophores differs from M. chuxiongense and M. indocalami. M. chuxiongense was cylindrical, straight, septate, 8–15 × 2–3 μm, M. indocalami was straight or slightly curved, septate, aggregated in the aerial mycelium (Table 2). In addition, the size and shape of conidiogenous cells also differ from two species, conidiogenous cells of M. indocalami was terminal or intercalary, denticulate, straight or bent, 11–28 × 2–3 μm. Nevertheless, M. chuxiongense was sparse, occasionally curved or swollen, 27–74 × 2–3 μm (Table 2). The size, shape and septate of conidia reported for M. indocalami (13–16 × 4–6 μm, cylindrical, clavate to obovoid, base usually flattened, 1–3-septate) were different from M. chuxiongense (4–12 × 2–5 μm, single or multiple, long oval, shuttle or sickle, straight or curved, 0–3-septate) (Table 2). Importantly, chlamydospores were observed in M. chuxiongense, and yet M. indocalami was not observed., Published as part of Tang, De-Xiang, Zou, Wei-Qiu, Wang, Yao-Ming, Huang, Ou & Yu, Hong, 2022, Morphology and phylogeny of Microdochium chuxiongense sp. nov., a fungus from Southwest China, pp. 147-158 in Phytotaxa 555 (2) on page 151, DOI: 10.11646/phytotaxa.555.2.3, http://zenodo.org/record/6875964, {"references":["Huang, S., Xia, J., Zhang, X., Sun, W. X. & Li, Z. (2020) Two new species of Microdochium from Indocalamus longiauritus in southwestern China. MycoKeys 72: 93 - 108. https: // doi. org / 10.3897 / mycokeys. 72.55445"]}

I feltforsøk med lett rulling av en rødsvingeldominert golfgreen ved Københavns golfklubb i 2020 og 2021 ble effekten på Microdochiumflekk studert. Greenen ble rullet to eller fire ganger i uka i tre eller fem måneder fram til november hvert år. Det var ikke noe soppangrep i 2021, men resultatene fra 2020 viste at rulling hadde statistisk sikker effekt og reduserte mikrodochiumflekk fra 5% på ubehandlet til 2,0 og 2,3 % der det var rullet henholdsvis to eller fire ganger i uka. Grønnfarge og visuelt helhetsinntrykk ble også påvirket av rulling. Helhetsinntrykket ble forbedret av rulling. Grønnfargen om høsten var best for ubehandlede ruter i 2020, men det var ingen forskjeller i 2021. Forsøket antyder at lett rulling to ganger i uka fra august til november kan redusere angrep av mikrodochiumflekk på rødsvingeldominerte greener i Skandinavia.

Denne rapporten oppsummerer foreløpige resultater fra 2020 i IPM-Golf-prosjektet "Ingergrated Management of Important Turfgrass Diseases and Insect Pests on European Golf-Courses" Feltforsøk på Microdochium flekk ble utført i Landvik, Norge og Bingley, Storbritannia. På Landvik viste resultatene at rulling ved lav N og sitronsyre, tilført fra aug.-okt. kan redusere Microdochium flekk til en viss grad blant de ikke-kjemiske behandlingene. Høy N resulterte i mer Mikrodochium flekk, men mindre antraknose. På Bingley viste resultatene at behandlingene som inneholder jernsulfat spesielt høyt jern, lyktes med å kontrollere sykdommen, men effekten varte ikke gjennom vinteren. Feltforsøkene ved Kjøpenhavns Golf Club viste at rulling to ganger i uken forbedret kvaliteten på greens gjennom vekstsesongen og at reduksjon av Microdochium flekk ble oppnådd ved å rulle fra august til desember. Feltforsøkene med UV-C-stråling ved Osnabrück Golf Club viste at denne metoden kunne kontrollere, men ikke bekjempe fullstendig dollar spot. Litteraturgjennomgangen om myrstankelbein og hageoldenborre viste at problemene varierer sterkt mellom år og de ulike landene.

Two fungal species of ascomycetes were discovered during the screening of soil microflora from the Gangwon Province in Korea: Didymella chlamydospora sp. nov. (YW23-14) and Microdochium salmonicolor sp. nov. (NC14-294). Morphologically, YW23-14 produces smaller chlamydospores (8.0–17.0 × 7.0–15.0 µm) than D. glomerata and D. musae. The strain NC14-294 was characterized by smaller conidiogenous cells (4.9–8.8 × 2.0–3.2 µm) compared with the closest strains M. fisheri and M. phragmitis. The detailed descriptions, illustrations, and discussions regarding the morphological and phylogenetical analyses of the closely related species are provided to support the novelty of each species. Thus, YW23-14 and NC14-294 are described here as newly discovered species.

The aims of this study were to quantify the viability of Microdochium albescens in irrigated rice seeds stored during the time between harvests and to quantify its incidence in the seed structures. Samples of irrigated rice seeds of the cultivars SCS122 Miura and SCS121 CL were monthly collected and stored during the time between harvests 2018/19. Pathology analysis and viability quantification were performed in the laboratory. The location of the fungus in the seeds was determined by separating lemma, palea, endosperm and embryo, with subsequent disinfestation and sowing in culture medium. The fungus M. albescens showed 77.8% seed storage viability for nine months, considering the average of lots and cultivars. Average incidence was 48% in the lemma, 43.7% in the palea, 24.7% in the endosperm and 20.7% in the embryo. The fungus M. albescens remains viable in rice seeds between harvests, while mycelium is detected at a higher incidence in the external tissues of caryopsis. RESUMO O objetivo deste trabalho foi quantificar a viabilidade de Microdochium albescens em sementes de arroz irrigado armazenadas durante a entressafra e quantificar sua incidência nas estruturas de sementes. Foram coletadas mensalmente amostras de sementes de arroz irrigado dos cultivares SCS122 Miura e SCS121 CL, armazenadas durante a entressafra 2018/19. A análise de patologia e quantificação de viabilidade foram realizadas em laboratório. A determinação da localização do fungo nas sementes foi quantificada separando-se lema, pálea, endosperma e embrião, com subsequente desinfestação e semeadura em meio de cultura. O fungo M. albescens apresentou durante nove meses viabilidade de armazenamento de sementes de 77,8%, considerando-se a média dos lotes e cultivares. A incidência média na lema foi de 48%, pálea 43,7%, endosperma 24,7% e embrião 20,7%. O fungo M. albescens mantém a viabilidade em sementes de arroz na entressafra e o micélio é detectado com maior incidência nos tecidos externos da cariopse.

Agents of biological control are an important part of traditional agriculture, as well as organic farming. However, in the climatic conditions of countries that are located in cold and temperate regions, plant protection requires particular biocontrol agents that have adapted to environments with low and unstable temperatures. This work presents the biocontrol potential and plant-promoting activity of Bacillus spp. that was isolated from permafrost sediments in Western Siberia. It was found that all of the studied strains (n = 10) were able to produce indole-3-acetic acid (IAA) and chitinolytic enzymes at low positive temperatures (5 °C). The antifungal activity of cold-tolerant bacilli against Microdochium sp., Fusarium spp., and Alternaria sp was recorded. In greenhouse and field conditions, the selected strains (B. simplex 948P-1 (IAA-producing) and B. megaterium 312 (with antifungal activity)) were assessed in comparison to a commercially available fungicide (tebuconazole) and biofungicide (B.subtilis 26D). It was found that the bacilli in the seed germination assay exhibited low phytotoxicity and there was no significant advantage over the conventional fungicides in the yield stimulation assay. However, the twin consortia of B. megaterium 312 and B. simplex 948P-1 was able to increase winter wheat yields by 50% (compared to the untreated group), and by 70% (compared to the commercial biofungicide-treated group). Moreover, applying the twin consortia of Bacillus spp. significantly reduced the infection rate of Fusarium spp. in first-generation wheat grain.

The fungus Microdochium albescens can interfere in the germination of seeds and in the death of rice seedlings; however, there is not technical indication for its control by seed treatment. This research evaluated the efficiency of fungicides in the treatment of pre-germinated and dryland rice seeds in the control of M. albescens. Seeds of the cultivars, Epagri 109, SCS116 Satoru, SCS121 CL and SCS122 Miura were treated with the following fungicides (g a.i./100 kg of seeds): fluazinam + thiophanate methyl (9.45 + 63), pyraclostrobin + thiophanate methyl (5 + 45), carboxin + thiram (60 + 60), metalaxyl-M + thiabendazole + fludioxonil (3 + 22.5 + 3.75), carbendazim + thiram (45 + 105), carbendazim (45). Seeds without fungicide treatment constituted the control. The treated seeds were sown in potato-sucrose-agar (PSA) culture medium and incubated at 25 ± 2 °C and photoperiod of 12 hours for 14 days. Treated seeds were also submitted to the germination test. Fluazinam + thiophanate methyl and metalaxyl-M + thiabendazole + fludioxonil showed greater control of M. albescens, not differing statistically between them, in the five cultivars and in the two cultivation systems. The tested fungicides provided seed germination above 90% in the four cultivars. RESUMO: O fungo Microdochium albescens pode interferir na germinação de sementes e na emergência de plântulas de arroz, porém não há indicação técnica para seu controle via tratamento de semente. Este trabalho teve como objetivo avaliar a eficiência de fungicidas em tratamento de sementes de arroz pré-germinado e sequeiro no controle de M. albescens. Sementes das cultivares Epagri 109, SCS116 Satoru, SCS121 CL e SCS122 Miura foram tratadas com os seguintes fungicidas (g i.a./100 kg de sementes): fluazinam + tiofanato metílico (9,45 + 63), piraclostrobina + tiofanato metílico (5 + 45), carboxina + tiram (60 + 60), metalaxil-M + tiabendazol + fludioxonil (3 + 22,5 + 3,75), carbendazim + tiram (45 + 105), carbendazim (45). Sementes sem tratamento com fungicida constituíram a testemunha. As sementes tratadas foram semeadas em meio de cultura de batata-sacarose-ágar (BSA) e incubadas a 25 ± 2°C e fotoperíodo de 12 horas por 14 dias. Sementes tratadas também foram submetidas ao teste de germinação. Fluazinam + tiofanato metílico e metalaxil-M + tiabendazol + fludioxonil apresentaram maior controle de M. albescens, não diferindo estatisticamente entre si, nas cinco cultivares e nos dois sistemas de cultivo. Contudo, os fungicidas testados proporcionaram germinação das sementes superior a 90% nas quatro cultivares.

Microdochium nivale and Microdochium majus cause brown foot rot and snow mould in cereals. The aim of the present study was to evaluate the population genetic structure of Microdochium spp. associated with foot rot of wheat in the Czech Republic and the reaction of that population to the succinate dehydrogenase inhibitor (SDHI) fungicide penthiopyrad. Using amplified fragment length polymorphism (AFLP) analysis to examine genetic structure, agar dilution to measure inhibitory effect, and various statistical methods to analyse populations, two genetic populations were found corresponding to the species Microdochium majus and M. nivale and restricted gene flow in populations between years was determined. This study demonstrates for the first time the occurrence of SDHI-insensitive reaction in populations of M. nivale and M. majus. Low sensitivity was identified in both species, but it was observed more frequently in M. majus populations.

Wheat stem base disease (WSD) is an important disease complex which can be caused by various pathogens with variable life cycles, ecological requirements and sensitivities to fungicides. Ag...

Occupational exposure to harmful bioaerosols in industrial environments is a real threat to the workers. In particular, dairy-farm workers are exposed to high levels of fungal bioaerosols on a daily basis. Associating bioaerosol exposure and health problems is challenging and adequate exposure monitoring is a top priority for aerosol scientists. Using only culture-based tools does not express the overall microbial diversity and underestimate the large spectrum of microbes in bioaerosols and therefore the extended fungal profile that farmers are exposed to. The aim of this study was to provide an in-depth characterization of fungal exposure at Eastern Canadian dairy farms using qPCR and high-throughput sequencing methods. Specific primers were used for the quantification of Penicillium/Aspergillus and Aspergillus fumigatus in dairy farms air samples. Illumina Miseq sequencing of the ITS1 region provided sequences for the diversity analyses. The minimum and maximum concentration of Penicillium/Aspergillus ranged from 4.6 × 106 to 9.4 × 106 gene copies/m3 and from 1 × 104 gene copies/m3 to 4.8 × 105 gene copies/m3 for Aspergillus fumigatus, respectively. Differences in the diversity profiles of the five dairy farms support the idea that the novel approach identifies a large number of fungal taxa. The most striking differences include Microascus, Piptoporus, Parastagonospora, Dissoconium, Microdochium, Tubilicrinis, Ganoderma, Ustilago, Phlebia and Wickerhamomyces. The presence of a diverse portrait of fungi in air may represent a health risk for workers who are exposed on a daily basis. The broad spectrum of fungi detected in this study includes many known pathogens like Aspergillus, Acremonium, Alternaria and Fusarium. Adequate monitoring of bioaerosol exposure is necessary to evaluate and minimize risks.

Tar spot is a fungal disease complex of corn that has been destructive and yield limiting in Central and South America for nearly 50 years. Phyllachora maydis, the causal agent of tar spot, is an emerging corn pathogen in the United States, first reported in 2015 from major corn producing regions of the country. The tar spot disease complex putatively includes Monographella maydis (syn. Microdochium maydis), which increases disease damage through the development of necrotic halos surrounding tar spot lesions. These necrotic halos, termed “fish-eye” symptoms, have been identified in the United States, though Monographella maydis has not yet been confirmed. A recent surge in disease severity and loss of yield attributed to tar spot in the United States has led to increased attention and expanded efforts to understand the disease complex and how to manage it. In this study, next-generation sequencing of the internal transcribed spacer 1 (ITS1) ribosomal DNA was used to identify fungal taxa that distinguish tar spot infections with or without fish-eye symptoms. Fungal communities within tar spot only lesions were significantly different from communities having fish-eye symptoms. Two low abundance operational taxonomic units (OTUs) were identified as Microdochium sp., however, neither were associated with fish-eye symptom development. Interestingly, a single OTU was found to be significantly more abundant in fish-eye lesions compared with tar spot lesions and had a 91% ITS1 identity to Neottiosporina paspali. In addition, the occurrence of this OTU was positively associated with Phyllachora maydis fish-eye symptom networks, but not in tar spot symptom networks. Neottiosporina paspali has been reported to cause necrotic lesions on various monocot grasses. Whether the related fungus we detected is part of the tar-spot complex of corn and responsible for fish-eye lesions remains to be tested. Alternatively, many OTUs identified as Phyllachora maydis, suggesting that different isolate genotypes may be capable of causing both tar spot and fish-eye symptoms, independent of other fungi. We conclude that Monographella maydis is not required for fish-eye symptoms in tar spot of corn.

Knowledge of the effect of the seedborne inoculum is important for knowing the level of tolerance of the pathogen by the seed. This research evaluated the effect of the incidence of the fungus Microdochium albescens on the physiological quality of the seeds of different cultivars of irrigated rice. The study was carried out in the seed testing laboratory (STL), phytopathology laboratory and in greenhouse, located at the Center of Agroveterinary Sciences of the Santa Catarina State University, Lages, SC, Brazil. Seeds from six irrigated rice cultivars produced in the Alto Vale do Itajaí Region in the 2016/17 harvest, were used. The lots were submitted to the seed health test, identifying four lots per cultivar with a natural incidence of M. albescens, with two lots of each cultivar with an incidence greater than 40% and two lots equal or less than 40%, totaling 24 seed lots. The following evaluations were carried out on the lots: germination, accelerated aging test, emergence in a greenhouse at 14 days, emergence speed index (ESI), emergence speed (ES), shoot length, root length and fresh and dry mass. There was a significant interaction between cultivar and level of incidence only in the variables germination, vigor and root length. Fresh mass, shoot length and ESI were not affected, regardless of cultivar and incidence of fungus in the seed. The irrigated rice cultivars SCS118 Marquês and SCSBRS Tio Taka are susceptible to a high incidence (> 40%) of the fungus M. allbescens. RESUMO: O conhecimento do efeito do inóculo na semente é importante para conhecimento do nível de tolerância do patógeno pela semente. Objetivo deste trabalho foi avaliar o efeito da incidência do fungo Microdochium allbescens sobre a qualidade fisiológica das sementes de diferentes cultivares de arroz irrigado. O estudo foi realizado nos laboratórios de análises de sementes (LAS), fitopatologia e na casa de vegetação, localizados no Centro de Ciências Agroveterinárias da Universidade do Estado de Santa Catarina, Lages, SC. Utilizaram-se sementes de seis cultivares de arroz irrigado produzidas na Região do Alto Vale do Itajaí na safra 2016/17. Os lotes foram submetidos ao teste de sanidade de sementes, identificando-se quatro lotes por cultivar com incidência natural de M. albescens, sendo designados dois lotes de cada cultivar com incidência superior a 40% e dois lotes igual ou inferior a 40%, totalizando 24 lotes de sementes. Foram realizadas as seguintes avaliações nos lotes: germinação, teste de envelhecimento acelerado, emergência em casa de vegetação aos 14 dias, índice de velocidade de emergência (IVE), velocidade de emergência (VE), comprimento de parte aérea, comprimento de raiz e massa seca. Houve interação significativa entre cultivar e nível de incidência apenas nas variáveis germinação, vigor e comprimento de raiz. A massa fresca, comprimento da parte aérea e IVE não foram afetados, independente do cultivar e incidência do fungo na semente. Os cultivares de arroz irrigado SCS118 Marquês e SCSBRS Tio Taka são suscetíveis à alta incidência (> 40%) do fungo M. albescens.

Triticale (×Triticosecale Wittmack) is obtained from wheat × rye crossing. It is positioned between wheat and rye in terms of resistance to soilborne pathogens including Gaeumannomyces graminis var. tritici, Fusarium culmorum, F. avenaceum, and Bipolaris sorokiniana (Arseniuk and Goral 2015). In 2019, seven triticale fields were surveyed in Almaty Province, Kazakhstan to examine soil-borne fungal pathogens. A total of 28 symptomatic plants with stunting, rot or discolored root were collected to identify causal agents. The overall disease incidence was approximately 8 to 10% in the fields. Fungi were isolated from 3-5 mm pieces excised from symptomatic tissues. The pieces were exposed to surface disinfection in 1% sodium hypochlorite solution for 2 min, rinsed three times with sterile distilled water, blotted dry, and plated on 1/5 strength potato dextrose agar (PDA) amended with 0.01% streptomycin. Plates were left in the dark at 23°C for 7 days. A total of 34 fungal colonies were isolated of which nineteen isolates, originally from six fields showed the cultural characteristics of B. sorokiniana. This species was previously reported to cause common root rot on triticale in Kazakhstan (Ozer et al. 2020). Ten isolates from four fields produced pale orange and cottony mycelium with red pigmentation on the agar, which is typical of Fusarium-like growth. The remaining isolates (n=5) from two fields produced salmon-colored and scarce aerial mycelium with no soluble pigmentation, similar to Microdochium spp. Fusarium isolates produced thick-walled and curved macroconidia with 3-4 septa (n=50, 25.7 to 37.6 × 4.1 to 7.3 μm in size) and notched basal cell on PDA, but microconidia were absent, which matches the description of F. culmorum (Wm.G. Sm.) Sacc. (Leslie and Summerell 2006). Microdochium isolates produced swollen, brown, and thick-walled chlamydospores and hyaline, one-celled, and thin-walled conidia (n=50, 5.4 to 9.3 × 1.5 to 3.0 μm in size) formed on ampullate and cylindrical conidiogenous cells on oatmeal agar (OA). These morphological features are consistent with previous observations for Microdochium bolleyi (R. Sprague) de Hoog & Herm.-Nijh. (Hong et al. 2008). To confirm morphological preliminary identifications, the portion of the translation elongation factor 1-alpha (EF1-α) gene was amplified with EF1/EF2 primers (O'Donnell et al. 1998) for representative Fusarium isolates (n=4) for each field. Additionally, the internal transcribed spacer (ITS) of ribosomal DNA was amplified with ITS1/ITS4 primers (White et al. 1990) for representative Microdochium isolates (n=2) for each field. BLASTn queries against NCBI GenBank revealed that the EF1-α sequences of Fusarium isolates (MW311081-MW311084) shared 100% identity with F. culmorum strain CBS 110262 (KT008433). The ITS sequences of M. bolleyi isolates (MW301448-MW301449) matched that of M. bolleyi strain CBS 137.64 (AM502264) with 100% sequence similarity. Pathogenicity test was conducted on pregerminated seeds of triticale cv. Balausa. A plastic pot (17 cm height, 9 cm in diam) was filled with a sterile mixture of vermiculite, peat, and soil (1:1:1, v/v/v). Mycelial plugs (1 cm in diam) were cut from the margin of a growing culture of representative isolates (Kaz_Fus123 and Kaz_Mb01) and placed onto the mixture in the pot. A sterile agar plug was employed as a control treatment. One pregerminated seed was put on the plug and covered with the mixture. The pots were transferred to a growth chamber set at 23 ± 2°C and a photoperiod of 14 hours. The experiment was performed twice using 5 replication pots per isolate. Four weeks after inoculation, discoloration of the crown was observed on all the inoculated roots, whereas no symptoms were observed on the control plants. Koch's postulates were fulfilled by reisolating and identifying the pathogen based on the morphology described above. This is the first report of M. bolleyi and F. culmorum causing root rot on triticale in Kazakhstan. Although B. sorokiniana is the most primary pathogen that may limit yield in the production of triticale in Kazakhstan, F. culmorum and M. bolleyi have been found to be less frequent and less aggressive pathogens, respectively. Further studies are needed to better understand the potential distribution and impact of these pathogens on triticale.

Snow mold is a severe plant disease caused by psychrophilic or psychrotolerant fungi, of which Microdochium species are the most harmful. A clear understanding of Microdochium biology has many gaps, the pathocomplex and its dynamic are poorly characterized, virulence factors are unknown, genome sequences are not available, and the criteria of plant snow mold resistance are not elucidated. Our study aimed to identify comprehensive characteristics of a local community of snow mold-causing Microdochium species colonizing a particular crop culture. By using the next-generation sequencing (NGS) technique, we characterized fungal and bacterial communities of pink snow mold-affected winter rye (Secale cereale) plants within a given geographical location shortly after snowmelt. Twenty-one strains of M. nivale were isolated, classified on the basis of internal transcribed spacer 2 (ITS2) region, and characterized by morphology, synthesis of extracellular enzymes, and virulence. Several types of extracellular enzymatic activities, the level of which had no correlations with the degree of virulence, were revealed for Microdochium species for the first time. Our study shows that genetically and phenotypically diverse M. nivale strains simultaneously colonize winter rye plants within a common area, and each strain is likely to utilize its own, unique strategy to cause the disease using &ldquo, a personal&rdquo, pattern of extracellular enzymes.

Plants-microbiome associations are the result of millions of years of co-evolution. Due to breeding-accelerated plant evolution in non-native and highly managed soil, plant-microbe links could have been lost. We hypothesized that post-domestication breeding of wheat changed the root-associated microbiome. To test this, we analyzed root-associated fungal and bacterial communities shortly after emergence of seedlings representing a transect of wheat evolution including modern wheat, landraces and ancestors. Numbers of observed microbial taxa were highest in landraces bred in low-input agricultural systems, and lowest in ancestors that had evolved in native soils. The microbial communities of modern cultivars were different from those of landraces and ancestors. Old wheat accessions enriched Acidobacteria and Actinobacteria, while modern cultivars enriched OTUs from Candidatus Saccharibacteria, Verrucomicrobia and Firmicutes. The fungal pathogens Fusarium, Neoascochyta and Microdochium enriched in modern cultivars. Both bacterial and fungal communities followed a neutral assembly model when bulk soil was considered as the source community, but accessions of the ancient Triticum turgidum and T. monococcum created a more isolated environment in their roots. In conclusion, wheat root-associated microbiomes have dramatically changed through a transect of breeding history.

Microdochium species have often been reported as plant pathogens and saprophytes and are commonly isolated from some diseased plant hosts. The primary aim of the present study was to describe and illustrate two new Microdochium species isolated from the leaf spot of Indocalamus longiauritus in Yunnan Province, China, namely Microdochium yunnanense and M. indocalami, spp. nov., based on their morphology and multilocus phylogenetic analyses of the combined ITS, LSU, TUB2, and RPB2. DNA sequence data indicate that six strains represent three independent groups from related and similar species in Microdochium. Microdochium indocalamisp. nov. clustered with M. fisheri, M. lycopodinum, M. rhopalostylidis, and M. phragmitis. Microdochium yunnanensesp. nov. grouped with M. bolleyi. In addition, the strain SAUCC1017 is recorded as an unidentified species in Microdochium. Descriptions and illustrations of the new species in the genus and Microdochium sp. indet. are provided.

The aim of this research was to identify and quantify fungi infecting irrigated rice seeds produced in the 2015/16, 2016/17 and 2017/18 harvests in the pre-germinated system in the Alto Vale do Itajaí Region, Santa Catarina State, Brazil. A total of 479 lots of eight cultivars were analyzed. Seeds were disinfected and sown in potato-sucrose-agar culture medium with incubation for seven days at 25ºC ± 2ºC and photoperiod of 12 hours. The main fungus detected in the three crops season was Microdochium albescens with 54.9% of average incidence, followed by Alternaria padwikii (7.7%) and Bipolaris oryzae (3.3%). RESUMO: O objetivo deste trabalho foi identificar e quantificar fungos infectando sementes de arroz irrigado, produzidas nas safras 2015/16, 2016/17 e 2017/18, no sistema pré-germinado na região do Alto Vale do Itajaí, estado de Santa Catarina. Foram analisados 479 lotes de oito cultivares, sendo as sementes desinfestadas e semeadas em meio de cultura de batata-sacarose-ágar com incubação por sete dias a 25ºC ± 2 ºC e fotoperíodo de 12 horas. O principal fungo detectado nas três safras foi Microdochium albescens com 54,9% de incidência média, seguido de Alternaria padwikii (7,7%) e Bipolaris oryzae (3,3%).

The biological characterization of Microdochium majus, M. nivale, and M. seminicola strains with wide geographical origins showed the diversity of their pathogenic properties and metabolite compounds, allowing them to exist in their habitats. Significant differences in the ability of Microdochium fungi to cause lesions on wheat and oat leaves were found. The intensity of symptoms depended on the species and substrate origin of the strains. On average M. seminicola strains were able to cause less leaf necrosis than M. majus and M. nivale. The volatile organic compound (VOC) profile of Microdochium fungi included 29 putative fungal metabolites. The spectrum of the identified VOCs in M. seminicola strains was much richer than that in M. majus and M. nivale strains. In addition, the strains of M. seminicola emitted at least six sesquiterpenes. Mycotoxin analysis by HPLC/MS/MS revealed that the analyzed Microdochium strains did not produce any toxic metabolites typically produced by filamentous fungi.

Dollar spot was officially documented in Scandinavia in 2013 and the spread and damage from this disease has increased during last years. In summer 2017, on the golf greens with red fescue (Vallda GC, Sweden) and with the mixture of red fescue, colonial bentgrass and annual bluegrass (Roskilde GC, Denmark) rolling 2 times per week reduced dollar spot 61% and 37% and rolling 4 times per week reduced dollar spot 95% and 54%, respectively. Thus, rolling 3-4 times per week can be recommended on golf greens with dollar spot pressure. In the experiment 2018 dollar spot was reduced 24% with increase in nitrogen from 150 to 240 kg ha-1 yr-1 on creeping bentgrass/annual bluegrass golf green (Kävlinge GK, Sweden). However, the increased N-rate lead to a higher degree Microdochium patch from 14% to 30%.

The Inland Pacific Northwest is one of the most productive dryland wheat production areas in the United States. We explored the bacterial and fungal communities associated with wheat in a controlled greenhouse experiment using soils from multiple locations to identify core taxa consistently associated with wheat roots and how land-use history influences wheat-associated communities. Further, we examined microbial co-occurrence networks from wheat rhizospheres to identify candidate hub taxa. Location of origin and land-use history (long-term no-till vs non-cropped Conservation Reserve Program (CRP) of soils were the strongest drivers of bacterial and fungal communities. Wheat rhizospheres were especially enriched in many bacterial families while only a few fungal taxa were enriched in the rhizosphere. There was a core set of bacteria and fungi that was found in >95% of rhizosphere or bulk soil samples, including members of Bradyrhizobium, Sphingomonadaceae, Massilia, Variovorax, Oxalobacteraceae, and Caulobacteraceae. Core fungal taxa in the rhizosphere included Nectriaceae, Pleosporaceae, Trichocomaceae, Mortierellaceae and Ulocladium, Microdochium, Macroventuria, and Cadophora. Overall, there were fewer core fungal taxa, and the rhizosphere effect was not as pronounced as with bacteria. Cross-domain co-occurrence networks were used to identify hub taxa in the wheat rhizosphere, which included bacterial and fungal taxa (eg. Sphingomonas, Massilia, Knufia, Microdochium). Our results suggest that there is a relatively small group of core rhizosphere bacteria that were highly abundant on wheat roots regardless of soil origin and land use history. These core communities may play important roles in nutrient uptake, suppressing fungal pathogens, and other plant health functions. IMPORTANCE Plant associated microbiomes are critical for plant health and other important agroecosystem processes. We assessed the bacterial and fungal microbiome of wheat grown in soils from across a dryland wheat cropping systems in Eastern Washington to identify the core microbiome on wheat roots that is consistent across soils from different locations and land use histories. Moreover, cross-domain co-occurrence network analysis identified core and hub taxa that may play important roles in microbial community assembly. Candidate core and hub taxa provide a starting point for targeting microbiome components likely to be critical to plant health and for constructing synthetic microbial communities for further experimentation. This work is one of the first examples of identifying a core microbiome on a major field crop grown across 100s of square kilometers over a wide range of biogeographical zones.

In total, 46 Microdochium strains from five different geographic regions of Russia were explored with respect to genetic diversity, morphology, and secondary metabolites. Based on the results of PCR, 59% and 28% of the strains were identified as M. nivale and M. majus, respectively. As a result of sequencing four genome regions, namely ITS, LSU, BTUB, and RPB2 (2778 bp), five genetically and phenotypically similar strains from Western Siberia were identified as M. seminicola, which, according to our findings, is the prevalent Microdochium species in this territory. This is the first record of M. seminicola in Russia. Attempts were made to distinguish between Microdochium species and to identify species-specific morphological characteristics in the anamorph and teleomorph stages and physiological properties. We examined the occurrence frequency of conidia with different numbers of septa in the strains of Microdochium. The predominance of three-septate macroconidia in M. majus was higher than that in M. nivale and typically exceeded 60% occurrence. Most M. majus and M. nivale strains formed walled protoperithecia on wheat stems. Only three strains of M. majus and one strain each of M. nivale and M. seminicola produced mature perithecia. The growth rate of M. seminicola strains was significantly lower on agar media at 5&ndash, 25 &deg, C than those of M. majus and M. nivale strains. Multimycotoxin analysis by HPLC-MS/MS revealed that the strains of three Microdochium species did not produce any toxic metabolites.

This is a report on the potential of NanoPro™to reduce the rate of two commonly used fungicides for control of Microdochium patch (Microdochium nivale), the economically most important turfgrass disease in Scandinavia. The experiment was conducted from 14 Sept. 2018 to 1 May 2019 on an annual bluegrass golf green at the NIBIO Turfgrass Research Center Landvik. Use of NanoPro™at a rate of 292 ml/ha in tank mixture with the systemic fungicide Delaro® SC 325 or/and the contact fungicide Medallion® TL produced the same level of disease control with a 30-60% reduction in fungicide dosage as with full fungicide dosage without additive. NanoPro™was more effective with Medallion® TL than with Delaro® SC 325. We conclude that NanoPro™may have a big potential in Scandinavia and other countries where authorities require reduced fungicide use. The experiment should be repeated one more year before giving final recommendations.

EnglishThe fungus Microdochium albescens is one of the main pathogens associated with irrigated rice seeds in southern Brazil. The objective of the present study was to quantify the transmission of M. albescens from naturally infected seeds to the crown, coleoptile, and first true leaf of the seedlings of six cultivars growing in pre-germinated cultivation system of irrigated rice. Seeding was carried out on a watersaturated substrate, using four untreated seed lots for each of the six cultivars. At 14 days after sowing, the crown, coleoptile, and first true leaf of the seedlings were carefully highlighted, and the samples were disinfected and plated onto potato-sucrose-agar culture medium. M. albescens was transmitted asymptomatically to crown, coleoptile, and first true leaf, at rates of 39.3%, 25.8%, and 5.4%, respectively (these values represent the average incidence of the six cultivars). This is the first report that proves that M. albescens is transmitted from infected seeds to irrigated rice seedlings in a pre-germinated seed system. portuguesO fungo Microdochium albescens e um dos principais patogenos associados as sementes de arroz irrigado no sul do Brasil. O objetivo do presente estudo foi quantificar a transmissao de M. albescens de sementes naturalmente infectadas para a coroa, coleoptilo e primeira folha verdadeira das plântulas de seis cultivares semeadas em sistema de cultivo pre-germinado de arroz irrigado. A semeadura foi realizada em substrato saturado com agua, utilizando quatro lotes de sementes nao tratadas para cada uma das seis cultivares. Aos 14 dias apos a semeadura, a coroa, o coleoptilo e a primeira folha verdadeira das plântulas foram cuidadosamente dissecados, desinfestados e plaqueados em meio de cultura batata-sacarose-agar. M. abescens foi transmitido de forma assintomatica para coroa, coleoptilo e primeira folha verdadeira, nas taxas de 39,3%, 25,8% e 5,4%, respectivamente (estes valores representam a incidencia media das seis cultivares). Este e o primeiro relato de M. albescens transmitido de sementes infectadas para plântulas de arroz irrigado em sistema de semente pre-germinada.

Sorghum leaves with concentric lesions, alternating purple to red and beige to cinnamon, were observed for the first time in January 2017. The same symptoms were observed later in 29 % of sorghum cultivars in official Evaluación Nacional de Cultivares inase-inia trials. The pathogen was identified as Microdochium sorghi (syn. Gloeocercospora sorghi) once pathogenicity trials, morphological and molecular descriptions were done. This is the first report of this pathogen affecting sorghum in Uruguay. Resumen: En enero de 2017 se observaron por primera vez hojas de sorgo con lesiones formando manchas concéntricas, alternando color púrpura o rojo con bandas beige o canela. La misma sintomatología fue observada posteriormente en el 29 % de los materiales de los ensayos de sorgo de Evaluación Nacional de Cultivares inase-inia. Una vez realizada la prueba de patogenicidad, descripción morfológica y molecular, se identificó al patógeno como Microdochium sorghi (sin. Gloeocercospora sorghi). Este es el primer reporte de este patógeno afectando sorgo en Uruguay.

The objective of this research was to evaluate bentgrass quality, growth, and disease incidence over a range of soil and tissue potassium levels. ‘Penn A4’ creeping bentgrass (Agrostis stolonifera L.) on a sand root zone was maintained as a putting green. The treatments included four levels of liquid potassium sulfate, ranging from 0 to 249 kg ha−1 yr.−1 K and one level of granular gypsum at a rate of 100 kg ha−1 yr.−1 Ca. No differences in vegetative or quality parameters were observed over the 6 year study period. Tissue K, Mehlich-3 extractable K, and Microdochium patch infection were all affected by treatment, with high-K treatments being greater than control and Ca treatments in all three instances. Near-daily turfgrass harvest resulted in much greater K removal than was estimated to be available from the pools extracted by Mehlich-3 and 1 M HNO3, suggesting that K became plant-available from more recalcitrant pool. Traditional soil testing methods may be inadequate for determining plant-available K in sand root zones. Total soil K analysis of the 0-K treatment indicated an increase in K during the study period, likely as a result of regular additions of sand via topdressing. Weathering of mineral K likely provided sufficient K to compensate for the lack of fertilizer.