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Severe leaf spot disease was observed on Aloe vera plants in the winters of 2011 and 2012 during a survey of various nurseries of Gwalior, India. Irregular, sunken, dark creamish brown spots having reddish brown margin were noticed on both surfaces of the leaves. The causal organism was consistently isolated from symptomatic leaves on potato dextrose agar media (PDA). A total 59 isolates of fungi were recovered from diseased A. vera leaves, and 37 isolates were identified as belonging to the genus Fusarium. On the basis of morphological characteristics and internal transcribed spacer (ITS) region of rDNA amplified using the primers ITS4/ITS5 the pathogen was identified as Fusarium proliferatum (Matsushima) Nirenberg and pathogenicity of the isolate was confirmed by using Koch’s postulates. To the best of our knowledge, this is the first report of leaf spot disease caused by Fusarium proliferatum on A. vera plants in India.

Cochliobolus lunatus (anamorph: Curvularia lunata) is a major pathogenic fungus that causes the Curvularia leaf spot of maize. ClMAT1-1-1 and ClMAT1-2-1, the C. lunatus orthologs of C. heterostrophus ChMAT1-1-1 and ChMAT1-2-1, were investigated in the present study to uncover their functions in C. lunatus. Southern blot analysis showed that these mating-type MAT genes exist in the C. lunatus genome as a single copy. ClMAT1-1-1 and ClMAT1-2-1 were knocked out and complemented to generate ΔClmat1-1-1 and ΔClmat1-2-1 and ΔClmat1-1-1-C and ΔClmat1-2-1-C, respectively. The mutant strains had defective sexual development and failed to produce pseudothecia. There were no significant differences in growth rate or conidia production between the mutant and wild-type strains. However, the aerial mycelia and mycelial dry weight of ΔClmat1-1-1 and ΔClmat1-2-1 were lower than those of wild type, suggesting that MAT genes affect asexual development. ClMAT genes were involved in the responses to cell wall integrity and osmotic adaptation. ΔClmat1-2-1 had a lower conidial germination rate than the wild-type strain CX-3. The virulence of ΔClmat1-2-1 and ΔClmat1-1-1 was also reduced compared with the wild-type. Complementary strains could restore all the phenotypes.

Didymella segeticola (Q. Chen) Q. Chen, Crous & L. Cai (syn. Phoma segeticola) is an important phytopathogen that causes leaf spot on tea, Camellia sinensis [L.] O. Kuntze, which results in huge te...

Pereskia aculeata is a non-conventional vegetable belonging to the family Cactaceae, native to the Americas. The leaves are very appreciated in cooking in some Brazilian regions, specially Minas Gerais. Plants of P. aculeata showing severe leaf spot diseases and stem rot were observed in Vicosa, state of Minas Gerais, Brazil. Colletotrichum sp. was observed on the diseased plant tissue and since no records of this fungus (and anthracnose disease) are reported for this host, the present study has aimed to identify the Colletotrichum sp. associated to P. aculeata and elucidate the etiology of the anthracnose disease. Based on the analyses of morphological characters combined with phylogenetic data from ITS, GAPDH, CHS-1, HIS3, ACT, and TUB2, a new species, namely Colletotrichum pereskiae sp. nov., is proposed, which belongs to the C. orchidearum species complex. A representative isolate was inoculated on healthy P. aculeata plants and reproduced the severe symptoms observed in the field. Colletotrichum pereskiae is the etiological agent of anthracnose on Pereskia aculeata in Brazil.

Background. Narrow-leaved lupine (Lupinus angustifolius L.) is an important high-protein forage and green manure crop, also promising for food use. This is a plastic species produced under various ecogeographic conditions and the only cultivated species of lupine adapted to high northern latitudes – up to 60° NL. Gradual expansion of lupine production areas led to the accumulation of pathogens, damage to lupine crops by harmful organisms, and significant harvest losses. Breeding and cultivating resistant varieties is the most profitable and environmentally sound way to control diseases and pests. Studying the species composition of pathogens and searching for source material are the necessary stages of plant breeding for immunity.Materials and methods. A set of 101 accessions of L. angustifolius from the VIR collection were studied in the northwest of the Russian Federation (Pushkin, St. Petersburg) in 2019, and 62 accessions from the same set in 2020. Mycological examination of the affected leaves was carried out on potato sucrose agar medium under laboratory conditions. The degree of damage to plants by diseases and infestation by pests was assessed during the period of flowering, fruit formation and ripening using point scales.Results and conclusions. A wide range of harmful organisms were identified for their negative impact on the growth and development of narrow-leaved lupine plants. The dominant pest was the lupine aphid (Macrosiphum albifrons Essig), discovered in Russia for the first time. A whole set of fungal pathogens was identified, among which the most common and harmful were the causative agents of Fusarium, brown leaf spot, powdery mildew, gray mold, and Sclerotinia stem rot. Narrow-leaved lupine accessions with weak degrees of pathogenic damage were selected.

During a disease survey on weeds and minor cultivated crops in Korea, a brown leaf spot disease was observed on Sonchus asper. Leaf lesions were round or irregular in shape, and grayish brown to brown with a purple margin. In severe infection, lesions enlarged and coalesced, resulting in blighting of the leaves. The isolates from these leaf lesions were identified as Alternaira sonchi based on morphological characteristics and phylogenetic analyses of Internal transcribed spacer region, Alternaria allergen a1, glyceraldehyde 3-phosphate dehydrogenase, RNA polymerase II, and translation elongation factor genes. This study provides a comprehensive description of the morphological characteristics and phylogenetical traits of A. sonchi causing brown leaf spot on S. asper in Korea.

Eggplant (Solanum melongena L.) is an economically important solanaceous crop in Iran with fruits used for food and traditional medicine. Despite the importance of Alternaria leaf spot and blight disease of solanaceous crops which is commonly seen in the fields, our knowledge about the causal agents on eggplant is limited. In this study, a set of large-spored Alternaria isolates was recovered from eggplant with leaf spot and blight symptoms in Somehsara region, Guilan province, Iran. All recovered isolates shared conspicuous morphological characteristics e.g. production of large, solitary conidia with several transverse disto- and eusepta and long tapering filamentous beak resemble those seen in the members of Alternaria section Porri. Multi-locus phylogenetic analyses based on the internal transcribed spacer region of nrDNA (ITS-rDNA) and parts of glyceraldehyde-3-phosphate dehydrogenase (GAPDH), second largest subunit of RNA Polymerase II (RPB2), translation elongation factor 1-alpha (TEF1-α) and Alternaria major allergen (Alt a 1) gene sequences provided further evidence supporting not only their exact placement in Alternaria sect. Porri, but also in a distinct lineage representing a new species. The new species was named, described and illustrated herein as Alternaria guilanica sp. nov.. The phylogenetic and morphological comaprisions of the new species with other closely related species were also provided. Pathogenicity test conducted for the new strains revealed that they were capable to induce disease symptoms on eggplant leaves under greenhouse conditions, and re-isolation of the inoculated isolates confirmed Koch’s postulates.

Diaporthe species are significant pathogens, saprobes, and endophytes, with comprehensive host association and geographic distribution. These fungi cause severe dieback, cankers, leaf spots, blights, and stem-end rot of fruits on different plant hosts. This study, explored the occurrence, diversity and pathogenicity of Diaporthe spp. associated with Actinidia chinensis and A. deliciosa in the main kiwifruit production areas of China. Diaporthe isolates (284) derived from 106 diseased leaf and branch samples were examined. Multi-locus phylogenetic analyses and morphology of 43 representative isolates revealed that seven Diaporthe species were obtained, including D. alangii, D. compactum, D. eres, D. hongkongensis, D. sojae, D. tectonae, and D. unshiuensis. Pathogenicity tests were performed on kiwifruit fruits, leaves and branches. Koch’s postulates confirmed all species were pathogenic. D. alangii and D. tectonae were the most aggressive species, followed by D. eres, D. sojae, D. hongkongensis, D. unshiuensis, and D. compactum. Host range evaluation showed that the seven Diaporthe species could also infect apricot, apple, peach, pear, and plum. This is the first report of D. alangii, D. compactum, D. sojae, D. tectonae, and D. unshiuensis infecting kiwifruit in China, increasing understanding of the Diaporthe complex causing diseases of kiwifruit plants, to assist effective disease management.

Leaf spot diseases caused by fungi pose a serious threat to forage crops due to the reduced photosynthetic area, which dramatically affects yields. Aiming to expand knowledge of fungi causing leaf spot diseases in ryegrass (Lolium multiflorum) from southern Brazil, a comprehensive survey was undertaken. Seven species of plant pathogenic fungi were encountered. All species were identified by using a polyphasic approach combining morphological, ecological, and molecular sequences of seven genomic loci (actin, calmodulin, glyceraldehyde 3-phosphate dehydrogenase, histone, ITS, LSU, and partial translation elongation factor 1-α). The pathogenicity of representative strains of each species was also tested after artificial inoculations. Cercospora sp. G, Colletotrichum plurivorum, and Exserohilum rostratum represent new-host associations, Bipolaris sorokiniana, Pyrenophora nobleae, and Pyricularia oryzae are newly reported for Brazil, and Curvularia lolii is newly described. These results form the basis to identify these diseases in the field, which in the future can help agronomists and farmers to design strategies for integrated control and management in crop-livestock production systems.

Endophytic bacteria have attracted a great attention because they produce chemicals that increase the resistance of host plants against diseases. In the current study, 40 strains of endophytic bacteria from Kobreasia capillifolia of an alpine grassland were screened for the inhibitory effect against the tomato leaf pathogen Pseudomonas syringae. The endophytic bacterium strain 262XY2’ developed a clear inhibition zone of growth with a bacteriostatic band width of 0.67 cm against P. syringae on the cultural plates. The strain 262XY2’ also showed an inhibitory activity to Bipolaris sorokiniana, Stysanus stemonitis, Alternaria soloni, Botrytis cinerea, Fusarium solani and F. oxysporum. It was able to fix nitrogen, dissolve phosphorus and produce indole 3-acetic acid (IAA). Based on morphological characteristics and the molecular sequence analyses of 16S rRNA and gyrB genes, the 262XY2’ strain was identified as Bacillus subtilis. B. subtilis 262XY2’ strain tagged with the green fluorescence protein (GFP) was found to colonize stably in the roots, stems and leaves of tomato plants, and could be re-isolated from the rhizosphere soil after 0 to 60 days of inoculation. Moreover, it also exhibited a control effect of 48.55% against tomato leaf spot caused by P. syringae. Our results indicate that the antagonistic bacteria B. subtilis 262XY2’ has the potential to be used as a biocontrol agent for tomato leaf spot.

Mother-in-law’s tongue, Dracaena (Sansevieria) trifasciata S. is an ornamental houseplant of Asparagaceae family and native to tropical western Africa and southern Asia. Following a yellow withered spot symptom observed on up to one third of D. trifasciata plants at the field, a new bacterium pathogen was discovered for the first time in South of China. This pathogen was isolated from the early irregular yellow spot and its pathogenicity to the host plant was confirmed through artificial infection. Through both morphological characteristics and molecular DNA sequences using 16S rDNA and three housekeeping genes, the pathogen was identified and characterized as Paenibacillus (Bacillus) polymyxa. Obviously, our research confirmed that P. polymyxa caused the leaf spot of D. trifasciata, which indicated that the biocontrol bacteria in the inherent knowledge could also infect some plants and cause diseases.

Fungal leaf spots disease is a main reason of rose (Rosa indica L.) crop failure in Pakistan. Isolation and identification of pathogen from rose plant was done by observing phenotypic characters which were further executed on molecular bases using ITS, EF and Bt2a/Bt2b primers. On these bases, pathogen was identified as Fusarium incarnatum. Then, Koch’s pathogenicity test was applied to confirm the virulence level of the isolated fungus by artificially inoculating it on R. indica seedlings in plate and pot trials. This study signifies the first report of F. incarnatum as a leaf spot pathogen of R. indica in Pakistan and highlights the need to explicate the management strategies of pathogen populations. © 2021 Friends Science Publishers

Ascochyta koolunga (Didymellaceae, Pleosporales) was first described in 2009 (as Phoma koolunga) and identified as the causal agent of Ascochyta blight of Pisum sativum (field pea) in South Australia. Since then A. koolunga has not been reported anywhere else in the world, and its origins and occurrence on other legume (Fabaceae) species remains unknown. Blight and leaf spot diseases of Australian native, pasture and naturalised legumes were studied to investigate a possible native origin of A. koolunga. Ascochyta koolunga was not detected on native, naturalised or pasture legumes that had leaf spot symptoms, in any of the studied regions in southern Australia, and only one isolate was recovered from P. sativum. However, we isolated five novel species in the Didymellaceae from leaf spots of Australian native legumes from commercial field pea regions throughout southern Australia. The novel species were classified on the basis of morphology and phylogenetic analyses of the internal transcribed spacer region and part of the RNA polymerase II subunit B gene region. Three of these species, Nothophoma garlbiwalawardasp. nov., Nothophoma naiawusp. nov. and Nothophoma ngayawangsp. nov., were isolated from Senna artemisioides. The other species described here are Epicoccum djirangnandirisp. nov. from Swainsona galegifolia and Neodidymelliopsis tinkyukukusp. nov. from Hardenbergia violacea. In addition, we report three new host-pathogen associations in Australia, namely Didymella pinodes on S. artemisioides and Vicia cracca, and D. lethalis on Lathyrus tingitanus. This is also the first report of Didymella prosopidis in Australia.

Eggplant brown leaf spot caused by Rhizoctonia solani AG-3 was first found in Japan in 1976, but its subgroup remained undetermined for over 40 years. We conducted a molecular phylogenetic analysis using three loci (rDNA-ITS, rDNA-IGS1, and tef-1α) of two Iwate isolates, newly obtained in this study, and one Tokyo isolate, which was previously identified as AG-2-2 IV and reported as an additional pathogen causing this disease. The phylogenetic tree based on these three loci revealed that the three isolates belonged to AG-3 TM. Eggplant is the first non-tomato host of AG-3 TM to be identified in Japan.

Cercospora canescens Ellis & Martin is an important fungal pathogen that causes leaf spot and defoliation in mungbean (Vigna radiata (Linn.) Wilczek.). Molecular methods for detection of this patho...

Pestalotioid fungi commonly occur as pathogens, endophytes or saprobes. In this study, pestalotioid fungi associated with leaf spots and fruit rots were isolated from Alpinia malaccensis, A. galangal, Annona squamosa, Artocarpus heterophyllus, Citrus sp., Garcinia mangostana, Litsea petiolata, a pteridophyte, and Vitis vinifera in Chiang Rai, Thailand. Based on single- and multi-locus phylogenies using internal transcribed spacer, β-tubulin and partial translation elongation factor 1-α gene regions, along with morphological features, the isolates were identified as two new species, Neopestalotiopsis hydeana and Pestalotiopsis hydei. This is the first time a Pestalotiopsis sp. was reported associated with Litsea petiolata and a Neopestalotiopsis sp. recorded from Alpinia, Annona, Artocarpus, Garcinia and a pteridophyte in the world. This fungal group can be considered as an emerging pathogenic group on different hosts in different climatic conditions.

Bacterial canker and leaf spot caused by plant pathogenic bacterium Pseudomonas is among the most destructive cherry diseases worldwide. Nowadays in Serbia, sweet cherry production significantly increased and the new plantations, mainly grown from imported planting material are being raised every year. During spring, 2018 and 2019, occurrence of bacterial canker and leaf spot symptoms was observed on a newly planted sweet cherry plantations in two localities, Zitoradja (Southern region) and Karavukovo (Northern region-Vojvodina). Typical P. syringae colonies were isolated on Nutrient Sucrose Agar supplemented with 5% sucrose (NSA). A total of fifteen isolates were selected and identified. Results of the LOPAT test (+---+) determined them to belong to fluorescent Pseudomonas Group Ia, while results of G+A+T-Ta- tests indicate presence of Pseudomonas syringae pv. syringae. Pathogenicity was confirmed on immature sweet and sour cherry fruitlets by forming of black, sunken lesions for all tested isolates. Genes syrB and syrD were successfully detected in all tested isolates. DNA sequencing using gapA, gltA, gyrB and rpoD housekeeping genes determined tested isolates to belong to P. s. pv. syringae using the National Center for Biotechnology Information (NCBI) nucleotide BLAST. The Serbian isolates shared 99.47% to 100% (Zitoradja) and 99.38% to 100% (Karavukovo) identity with bacterium P. s. pv. syringae. Phylogenetic analysis grouped isolates from Zitoradja in one tree cluster, separate from the Karavukovo isolates, indicating presence of two genetically diverse groups of causal pathogen P. s. pv. syringae, obtained from two geographically distinct localities in Serbia. Phylogeographic analysis grouped isolates from Zitoradja in multilocus haplotype coded as REz and isolates originated from Karavukovo in multilocus haplotype coded as REk. Considering that during last few years P. syringae continuously occurs mainly in young sweet cherry plantations, where imported material is used for raising, health status check is recommended to be included as obligatory measure when nursery material is used from import.

This paper introduces an interesting new fungus, isolated from teak (Tectona grandis) leaf-spots, collected in Chiang Rai Province, Thailand. Phylogenetic analysis of combined ITS and LSU sequence data together with morphological studies confirmed that the disease was caused by a Bartalinia species, distinct from described taxa. Detailed description, photomicrographs and a phylogenetic tree are provided to showcase the taxonomic placement of the new species, B. kevinhydei. Geographical distribution of Bartalinia species is also provided. This is the first report of a Bartalinia species growing on teak, and also the first report for Bartalinia in Thailand.

Species ofColletotrichumare considered among the most important plant pathogens, saprobes and endophytes on a wide range of ornamentals, fruits and vegetables. SeveralColletotrichumspecies have been reported in nurseries and public or private gardens in northern Italy. In this study, the occurrence, diversity and pathogenicity ofColletotrichumspp. associated with several ornamental hosts was explored. Survey were carried out during the 2013–2019 period in Piedmont, Italy. A total of 22Colletotrichumisolates were collected from symptomatic leaves and stems of twoCampanulaspp.,Ceanothus thyrsiflorus,Coreopsis lanceolata,Cyclamen persicum,Hydrangea paniculata,Liquidambar styraciflua,Mahonia aquifoliumandRhyncospermum jasminoides. A multi-locus phylogeny was established based on the basis of three genomic loci (gapdh,actandtub2). The pathogenicity of selected, representative isolates was tested.Colletotrichumisolates were identified as members of four important species complexes: Acutatum,Gloeosporioides,DematiumandDestructivum.Colletotrichum fioriniae,C. nymphaeaeandC. fuscumwere found in association with leaf lesions ofMahonia aquifolium,Campanula rapunculoidesandCoreopsis lanceolata, respectively.Colletotrichum lineola,C. grossumandC. cigarrowere isolated fromCampanula trachelium,Rhyncospermum jasminoidesandLiquidambar styraciflua, respectively.Colletotrichum fructicolawas found to be responsible of anthracnose ofCeanothus thyrsiflorus,Hydrangea paniculata,Cyclamen persicumandLiquidambar styraciflua. All the tested isolates were pathogenic and reproduced identical symptoms to those observed in private gardens and nurseries. The present study improves our understanding ofColletotrichumspp. associated with different ornamental hosts and provides useful information for an effective disease management programme.

Background.Soybean (Glycine max (L.) Merr.) gradually becomes one of the leading legume crops in Kazakhstan. The area under soybeans in the country has been increasing annually and requires the development of adapted cultivars with a higher yield, improved quality characters, and resistance to emerging fungal diseases. The enlargement of the crop’s gene pool also suggests the need to study and document local soybean accessions to meet the standards of the available world soybean collection by using reliable and informative types of DNA markers.Materials and methods. In this study, the soybean collection consisting of 288 accessions from different countries, including 36 cultivars and promising lines from Kazakhstan, was studied. The molecular genetic analysis was performed using nine polymorphic SSR (simple sequence repeats) markers, seven of which (Satt244, Satt565, Satt038, Satt309, Satt371, Satt570 and Sat_308) were associated with resistance to three main fungal diseases of soybean – frogeye leaf spot, fusarium root rot, and purple seed stain.Results. The average PIC (polymorphism information content) value of the analyzed SSR markers constituted 0.66 ± 0.07, confirming their highlevel polymorphism. The principal coordinate analysis suggested that the local accessions were genetically most close to the accessions from East Asia. As the collection showed a robust resistance to three studied fungal diseases in Almaty Region during 2018–2019, the distribution of the studied SSR markers in the population was not significantly associated with resistance to the analyzed diseases under field conditions.Conclusion. SSR genotyping of the soybean collection helped to identify accessions that potentially possess resistance-associated alleles of fungal disease resistance genes. The data obtained can be further used for the development of DNA documentation and the breeding the promising cultivars and lines of soybean.

In recent years in China, leaf spot caused by Colletotrichum species has been an emerging disease of Philodendron tatei cv. Congo. From 2016 to 2019, typical symptoms, appearing as circular or ovoid, sunken, and brown lesions with a yellow halo, were commonly observed on P. tatei cv. Congo in and around Lanzhou, Gansu Province, China. Conidiomata were often visible on infected leaf surfaces. Leaf disease incidence was approximately 5 to 20%. A total of 126 single-spored Colletotrichum isolates were obtained from leaf lesions. Multilocus phylogenetic relationships were analyzed based on seven genomic loci (ITS, ACT, GAPDH, HIS3, CAL, CHS-1, and TUB2) and the morphological characters of the isolates determined. These isolates were identified as three Colletotrichum species in this study. A further 93 isolates, accounting for 74% of all Colletotrichum isolates, were described as new species and named as Colletotrichum philodendricola sp. nov. after the host plant genus name, Philodendron; another two isolates were named as C. pseudoboninense sp. nov. based on phylogenetic and morphological relativeness to C. boninense; the other 31 isolates, belonging to the C. orchidearum species complex, were identified as a known species—C. orchidearum. Both novel species C. philodendricola and C. pseudoboninense belong to the C. boninense species complex. Pathogenicity tests by both spray and point inoculations confirmed that all three species could infect leaves of P. tatei cv. Congo. For spray inoculation, the mean infection rate of leaves on the three species was only 4.7% (0 to 12%), and the size on lesions was mostly 1 to 2 mm in length. For point inoculation, 30 days after nonwounding inoculation, the infection rate on leaves was 0 to 35%; in wounding inoculation, the infection rate of leaves was 35 to 65%; wounding in healthy leaves greatly enhanced the pathogenicity of these three species to P. tatei cv. Congo; however, the sizes of lesions among the three species were not significantly different. To our knowledge, this is the first report of Colletotrichum species associated with anthracnose diseases on P. tatei cv. Congo. Results obtained in this study will assist the disease prevention and appropriate management strategies.

Chinese mesona (Platostoma palustre) plays an important role as special crop in Southeast Asia and Taiwan for the production of herbal tea, grass jelly, and further processed food. In order to assess the potential threat of fungi to Chinese mesona, we surveyed isolates from symptomless plants in the area of mesona production, as well as from leaf spots of potted plants in a garden shop and a plantation in a botanical garden in Taiwan. From leaves, stems, and roots of 15 symptomless plants sampled at five collection events over two years, 154 isolates from 810 surface-sterilized plant fragments were obtained and identified based on DNA sequence data of the internal transcribed spacer region, and partially of the β-tubulin and histone H3 genes. The most common species belonged to the genera Cercospora, Colletotrichum, and Fusarium and were considered to be potential plant pathogens. Latent pathogenicity was confirmed by an infection experiment with an endophytic strain of Corynespora cassiicola. Observation of leaf spot disease associated with Cercospora kikuchii suggested pathogenicity of this fungus, which was also isolated as an endophyte from symptomless leaves. We hypothesize that the most common endophytic fungi are latent pathogens in the host and may cause plant disease when the host becomes weakened by senescence or changed cultivation condition. Leaf spots of plants in the botanical garden were associated with a species of Pseudocercospora, which was not found among the endophytic isolates and is newly described based on morphology and analysis of translation elongation factor 1 alpha gene sequences.

Leaf spot is a common disease of cassava in Indonesia and other tropical countries. The present study aims to determine two isolates isolated from leaf spot of cassava in Indonesia using a molecular phylogenetic analysis based on internal transcribed spacer (ITS) rDNA sequence and morphological examination. The results showed that the two isolates belong to Clarohilum henningsii. This study revealed the phylogenetic position of C. henningsii from Indonesia, where in the previous studies, it has been reported as Cercospora cassavae, C. manihotis, C. henningsii, or Passalora henningsii based on morphological examinations.

Pleosporales species are important plant pathogens, saprobes, and endophytes on a wide range of economically important plant hosts. The classification of Pleosporales has undergone various modifications in recent years due to the addition of many families described from multiple habitats with a high level of morphological deviation. Numerous asexual genera have been described in Pleosporales that can be either hyphomyceteous or coelomycetous. Phoma- or coniothyrium-like species are common and have been revealed as polyphyletic in the order Pleosporales and linked with several sexual genera. A total of 31 pleosporalean strains were isolated in different regions of Taiwan between 2017 and 2018 from the leaves of Camellia sinensis plants with symptoms of leaf spot disease. These strains were evaluated morphologically and genotypically using multi-locus sequence analyses of the ITS, LSU, SSU, rpb2, tef1 and tub2 genes. The results demonstrated the affiliation of these strains with the various families in Pleosporales and revealed the presence of one new genus (Neoshiraia) and eight new species (Alloconiothyrium camelliae, Amorocoelophoma camelliae, Leucaenicola camelliae, L. taiwanensis, Neoshiraia camelliae, N. taiwanensis, Paraconiothyrium camelliae and Paraphaeosphaeria camelliae). Furthermore, to the best of our understanding, Didymella segeticola, Ectophoma pomi and Roussoella mexican were reported for the first time from C. sinensis in Taiwan.

Local pathogens can accumulate as asymptomatic endophytes, making it difficult to detect the impacts of invasive species as propagators of disease in the invaded range. We used the invasive plant Ageratina adenophora to assess such accumulation. We intensively collected foliar fungal endophytes and leaf spot pathogens of A. adenophora and co-occurring neighbours and performed an inoculation experiment to evaluate their pathogenicity and host range. Ageratina adenophora harboured diverse necrotrophic pathogens; its communities of endophytes and leaf spot pathogens were different in composition and shared only a small number of fungal species. In the pathogen communities of local plant hosts, 21% of the operational taxonomic units (OTUs), representing 50% of strains, also occurred as leaf spot pathogens and/or endophytes of A. adenophora. The local pathogen community was more similar to the endophytes than to the pathogens of A. adenophora. The inoculation experiment showed that local pathogens could infect A. adenophora leaves asymptomatically and that local plant hosts were susceptible to both A. adenophora endophytes and pathogens. Ageratina adenophora is a highly competent host for local pathogens, and its asymptomatic latent pathogens are fungi primarily shared with local neighbours. This poses challenges for understanding the long-term ecological consequences of plant invasion.

Leaf spot diseases caused by Alternaria species have been reported worldwide in plants in the Brassicaceae family. However, there is little information on Alternaria species causing diseases in horseradish. In the present study, 89 Alternaria spp. isolates from Armoracia rusticana, sampled from nine districts in Serbia, were characterized based on their morphology, physiology, and molecular markers. Morphological characterization and molecular analyses based on ITS, GAPDH, Alt a 1, and PM-ATP sequences identified three distinct species associated with the disease: Alternaria brassicae, A. brassicicola, and A. alternata. For all species, growth and sporulation rates at 0, 5, 10, 15, 20, 25, 30, 35, and 40°C showed a quadratic response, with A. alternata having the widest temperature optimum (20 to 30°C) while A. brassicicola had higher optimum temperatures (20 to 25°C) than A. brassicae (15 to 20°C). To gain a better understanding of the pathogenicity of these species, the influence of leaf age, host susceptibility, and ability to infect artificially wounded and nonwounded leaves were tested. The pathogenicity test identified A. brassicicola and A. brassicae as the main causal agents of horseradish leaf spot disease. Results indicated that young and intact leaves of horseradish and cabbage were less susceptible to infection and also suggested the potential for cross-infection between these two hosts. Haplotype networks showed haplotype uniformity for A. brassicae, two haplotype groups of A. brassicicola, and eight haplotype groups of A. alternata in Serbia and suggest the possible association of some haplotypes with the geographic area. This study is the first to investigate Alternaria leaf spot disease on A. rusticana in Serbia and is the first record of A. brassicicola on horseradish in this country.

During a biodiversity survey of Alternaria associated with leaf spot and blight of Solanaceae, a large collection of strains was obtained from samples collected in north-western regions of Algeria in 2013–2018 growing seasons. Amongst these strains, three isolates recovered from tomato and potato had morphological traits different from that usually observed for Alternaria species previously reported on Solanaceae. Based on analysis of a sequence dataset corresponding to portions of the glyceraldehyde-3-phosphate dehydrogenase (gpd), translation elongation factor 1-alpha (tef1) and RNA polymerase second largest subunit (rpb2) genes along with morphological observations, isolates were identified as a new species in the section Japonicae. This novel species, described here as Alternaria telliensis, is phylogenetically and morphologically distinct from A. japonica and A. nepalensis in this section. Pathogenicity tests were performed and isolates were found to be weakly pathogenic to tomato and potato (Solanaceae) while highly aggressive on radish, cabbage and turnip (Brassicaceae) plants.

Leaf spot disease was detected on Sansevieria trifasciata in Malaysia. Two Curvularia species namely C. eragrostidis and C. asianensis were isolated as the pathogens. The isolated fungi were identified based on morphology and multigene phylogeny (ITS, GAPDH and TEF1‐α). Pathogenicity tests confirmed the roles of both Curvularia isolates in causing leaf spot of S. trifasciata. To our knowledge, this is the first report of C. eragrostidis and C. asianensis causing leaf spot of S. trifasciata in Malaysia.

A fungus within the genus Phaeosphaeriaceae was isolated from brown leaf spot samples of Dracaena serrulata Baker (Yemen dragon tree) collected from Oman Botanic Garden, Muscat, Oman. Detailed morphological studies showed that this strain fits well within the species concept of the genus Phaeosphaeriopsis. Multilocus phylogeny based on LSU, ITS and TEF confirmed its uniqueness and supports its recognition as a new species, Phaeosphaeriopsis omaniana. Geography, pathogenic life mode and subglobose, smooth and brown conidia of the newly described species clearly differ from those of phylogenetically related species. A comprehensive description and illustrations of the new species, P. omaniana is provided and discussed with comparable taxa.

This study was initiated to elucidate the taxonomy and host range of Stemphylium species associated with leaf spot of faba bean in Australia. A three-locus phylogenetic analysis of 41 isolates collected from faba bean and other Fabaceae and Brassicaceae crops was constructed employing the internal transcribed spacers and the intervening 5.8S region of the nuclear ribosomal DNA, glyceraldehyde 3-phosphate dehydrogenase, and calmodulin sequences. The results indicated that more than one Stemphylium species occurs on faba bean (Vicia faba), chickpea (Cicer arientinum), lentil (Lens culinaris), and narrow-leafed lupin (Lupinus angustifolius) in Australia. Five Stemphylium species (S. astragali, S. beticola, S. eturmiunum, S. simmonsii, and S. vesicarium) were found associated with legume crops, of which S. astragali is a new report for Australia. Although isolates obtained from faba bean were retrieved within S. eturmiunum and S. vesicarium clades, those pathogenic to faba bean belonged to S. eturmiunum, a species not previously reported on faba bean. Interestingly, some S. eturmiunum isolates obtained from faba bean and other legumes were unable to infect faba bean, which indicated the potential presence of formae speciales within this species. The ability of S. eturmiunum isolates to cause plant death in susceptible faba bean varieties within only a few days emphasises the need for incorporation of Stemphylium blight resistance into faba bean breeding programs. Also, further research into the biology and epidemiology of the disease is warranted.

Light leaf spot, caused by the ascomycete Pyrenopeziza brassicae, is an established disease of Brassicaceae in the United Kingdom (UK), continental Europe, and Oceania (OC, including New Zealand and Australia). The disease was reported in North America (NA) for the first time in 2014 on Brassica spp. in the Willamette Valley of western Oregon, followed by detection in Brassica juncea cover crops and on Brassica rapa weeds in northwestern Washington in 2016. Preliminary DNA sequence data and field observations suggest that isolates of the pathogen present in NA might be distinct from those in the UK, continental Europe, and OC. Comparisons of isolates from these regions using genetic (multilocus sequence analysis, MAT gene sequences, and rep-PCR DNA fingerprinting), pathogenic (B. rapa inoculation studies), biological (sexual compatibility), and morphological (colony and conidial morphology) analyses demonstrated two genetically distinct evolutionary lineages. Lineage 1 comprised isolates from the UK, continental Europe, and OC, and included the P. brassicae type specimen. Lineage 2 contained the NA isolates associated with recent disease outbreaks in the Pacific Northwest region of the USA. Symptoms caused by isolates of the two lineages on B. rapa and B. juncea differed, and therefore "chlorotic leaf spot" is proposed for the disease caused by Lineage 2 isolates of P. brassicae. Isolates of the two lineages differed in genetic diversity as well as sensitivity to the fungicides carbendazim and prothioconazole.