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Phyllosticta cavendishii has been recorded in the Northern Territory (NT) of Australia occurring on non‐Cavendish bananas since 1991. The race of P. cavendishii that infects Cavendish bananas is considered exotic to Australia and classified as an emergency plant pest. In July 2013, P. cavendishii was detected on Cavendish bananas near Darwin, NT. Here, the diagnoses and field observations carried out during the Incident Definition Phase of the national biosecurity response, from July 2013 to October 2014, are reported. Of 1395 banana samples collected from 676 properties, 480 were positive for freckle disease, including 463 samples with P. cavendishii and 17 samples with P. maculata. Phyllosticta cavendishii was detected in 256 properties, including 62 properties where it was detected on Cavendish banana plants, within six distinct geographical zones across the NT. Phyllosticta cavendishii was detected on two cultivars within the Cavendish subgroup and six non‐Cavendish cultivars. Multigene characterization of Phyllosticta cultures showed that P. cavendishii was isolated from both Cavendish and non‐Cavendish cultivars. Multilocus phylogeny analyses also revealed that the P. cavendishii strain in the outbreak had identical sequence similarity to the holotype (CBS H‐20918) clade 2 P. cavendishii isolates that infect both Cavendish and non‐Cavendish cultivars in Southeast Asia and Oceania. The genetic data in this study showed that there was one P. cavendishii strain infecting both Cavendish and non‐Cavendish cultivars in the outbreak. However, historical data and field observations provided anecdotal evidence for the existence of two races of P. cavendishii, including one that does not infect Cavendish bananas.

Tea white scab disease commonly occurs in high‐altitude tea‐growing areas worldwide. Both Elsinoe leucospila and Phyllosticta theaefolia have been reported as the pathogen responsible for this disease. To conclusively identify the causative agent, samples were collected from plants infected with tea white scab disease in high‐altitude tea gardens in southern China. Fungal isolates obtained from the infected material were identified based on morphological characteristics, comparisons of ITS, 18S rDNA, RPB2 and LSU sequences, and pathogenicity tests. Both Elsinoe sp. and Phyllosticta sp. were isolated from the collected samples with rates of 6% and 35%, respectively. On potato dextrose agar medium, Phyllosticta sp. grew faster and sporulated more than E. leucospila. However, only E. leucospila caused symptoms similar to those of tea white scab disease. In contrast, Phyllosticta sp. infections resulted in large necrotic spots. Therefore, E. leucospila appears to be the pathogen responsible for tea white scab disease, whereas Phyllosticta sp. is a hyperparasitic fungus that infects the diseased plant tissue. The high isolation rate of Phyllosticta sp. due to its rapid growth and considerable sporulation may have led to the erroneous identification of this fungus as the cause of tea white scab disease. Our findings may be useful for future investigations of this disease, particularly regarding the development of improved prevention and/or control measures.

A survey of small-holder banana farms was undertaken in February/March 2019 in Savannakhet, Salavan, Sekong and Champasak provinces in southern Lao People’s Democratic Republic (Lao PDR) to establish which banana leaf pathogens were present. Twenty-five farms were visited, seven different cultivars were assessed, and 13 leaf samples with characteristic symptoms of banana freckle disease collected. Phyllosticta musarum was detected on the variety ‘Kuay Nam’ in each of the four provinces surveyed. Phyllosticta cavendishii was detected in Salavan, Sekong and Champasak. Phyllosticta musaechinesis was recorded from Champasak. This is the first time these three species have been recorded associated with banana freckle disease in the Lao PDR.

The horse chestnut, Aesculus hippocastanum L., is a common tree in urban and rural environments of Europe. Invasion by Cameraria ohridella (Deschka & Dimic) started three decades ago, and to date, the whole European range of A. hippocastanum has been infected. With the addition of the fungal agent of leaf blotch Phyllosticta paviae (Desmazieres), a new tripartite interaction arose, and a possible complex disease has been established. In this study, we aimed to answer the following question: do females of C. ohridella deposit eggs more frequently on healthy leaflets than on infected ones? In two experiments, leaves were previously infected by leaf blotch, and leaf miners were absent. In the choice test, one fertilised female was put into a box with healthy and infected leaflets. The second experiment was conducted under greenhouse conditions; an unknown number of females were exposed to leaf-blotch-infected and healthy saplings. Eggs were deposited mainly on healthy areas of leaves and always in leaf depressions. A positive relationship between the number of chosen leaflets and the number of deposited eggs was found when a single female was allowed to choose. In both experiments, we found that healthy leaflet area rather than the presence or absence of leaf blotch disease was the factor explaining the number of deposited eggs. We conclude that C. ohridella females are spreading the risk by ovipositing on many leaflets rather than avoiding the potential decrease in offspring survival.

An extensive literature search was performed to review current knowledge about endophytic fungi isolated from plants included in the European Food Safety Authority (EFSA) dossier. The selected genera of plants were Acacia, Albizia, Bauhinia, Berberis, Caesalpinia, Cassia, Cornus, Hamamelis, Jasminus, Ligustrum, Lonicera, Nerium, and Robinia. A total of 120 fungal genera have been found in plant tissues originating from several countries. Bauhinia and Cornus showed the highest diversity of endophytes, whereas Hamamelis, Jasminus, Lonicera, and Robinia exhibited the lowest. The most frequently detected fungi were Aspergillus, Colletotrichum, Fusarium, Penicillium, Phyllosticta, and Alternaria. Plants and plant products represent an inoculum source of several mutualistic or pathogenic fungi, including quarantine pathogens. Thus, the movement of living organisms across continents during international trade represents a serious threat to ecosystems and biosecurity measures should be taken at a global level.

Black spot is a common disease occurring on Dendrobium officinale, which significantly reduces the quality and yield of this medicinal plant (family Orchidaceae). The disease manifests itself as small, black spots on leaves which can develop into circular streaks that become necrotic tan or brownish black, with the leaves eventually turning yellow or brown-yellow. Fungal pathogens such as Alternaria tenuissima and Phyllosticta spp. are known to cause black spot of D. officinale. A fungus which was atypical of A. tenuissima or Phyllosticta spp. was isolated from leaves of D. officinale showing symptoms of black spot from Zhejiang and Guangxi provinces, China. Pathogenicity tests in vitro as well as on tissue-cultured seedlings using fungal isolate GXDF24 showed that it was able to cause typical black spot symptoms. Molecular identification based on the ITS sequence revealed that isolate GXDF24 shared 99% similarity with Cladosporium oxysporum. This is the first report of C. oxysporum as a pathogen causing black spot of D. officinale in China.

Several needle blight fungi affect natural regeneration and Christmas tree plantations of Abies spp. in northeastern North America. Of these, Phyllosticta multicorniculata Bissett & Palm has been reported from A. balsamea (L.) Mill. in Ontario and Prince Edward Island, and from A. concolor (Gordon & Glend.) Lindl. ex Hildebr. in Wisconsin (1). In Quebec, P. multicorniculata was reported as an endophyte on symptomless needles of A. balsamea (2). In 1994, we collected this fungus in Grafton County, NH, defoliating lower branches of A. balsamea Christmas trees. In July and August 1996, we examined infected A. concolor Christmas trees in Lamoille County, VT. In July, approximately 50% of the 1996 needle complement on the lower 1 m of the crowns was infected and by August the incidence of infection on these branches increased to 75 to 100%. Less severe blighting occurred up to 1.5 m. Dead needles of the 1995 complement bore abundant, mostly empty, pycnidia of P. multicorniculata. The dead and dying distal ends of the 1996 needle complement bore abundant pycnidia of P. multicorniculata in various stages of maturation. This is the first report of this pathogen on Abies spp. in the northeastern U.S. The conidia from actively-sporulating pycnidia bore more numerous and longer appendages (1 to 16, average 7, up to 38 µm long) than the dried herbarium specimens of various ages used in the species description (1 to 5, up to 7 µm long) (1), or similarly reported from culture (2). References: (1) J. Bissett and M. E. Palm. Can. J. Bot. 67:3378, 1989. (2) L. Petrini et al. Sydowia 43:148, 1991.

This study aimed to identify and characterize the pathogens associated with symptoms similar to Phaeosphaeria leaf spot (PLS) of maize in different environmental conditions in Brazil. During the last decade, PLS became an important disease of maize in Brazil. However, doubt persists about the causal agent. Maize leaves with PLS-like lesions were collected from two locations (Cristalina, Goiás State [GO] and Vila Maria, Rio Grande do Sul State [RS]) in two growing seasons. Fungi associated with leaf lesions were isolated and cultured for taxonomic identification. Pathogenicity tests were carried out and the results indicated that three fungi (a Phyllosticta sp., Phoma sorghina, and a Sporormiella sp.) caused leaf spot similar to PLS on maize. The composition of pathogenic fungi in PLS-like lesions varied depending on locations and growing seasons. The fungi P. sorghina and a Phoma sp. (Plenodomus section) occurred in all environments, but the Sporormiella and Phyllosticta spp. were restricted to GO and RS, respectively. The results support the hypothesis that various pathogens are involved in PLS-like symptoms of maize and environmental conditions may influence the predominance of a specific agent.

During August 2003, guava fruit (Psidium guajava L.) cv. Red Dominicana from Cojedes state in Venezuela showed circular, purple-to-brown lesions (0.5 to 1.0 cm) that spread over all surfaces and became black and shrunken on severely affected fruit. Symptomatic tissues were plated aseptically on potato dextrose agar (PDA). Colonies that were initially gray and turned black with age were consistently isolated. The fungus was characterized by dense, submerged, brown-to-black mycelium with septate hyphae. Ascocarps were perithecial, abundant, granulose, subglobose to cylindric obpyriform, solitary or aggregated, mostly unilocular with prominent long necks; ascocarp walls were stromatic, composed of several layers of cells, thick walled, and deeply pigmented on the outside. Asci were subclavate to cylindrical, stipitate, 44 to 84 × 7 to 9 μm, and eight-spored; asci walls were thick and bitunicate. Ascospores were unicellular, hyaline, guttulate, fusiform ellipsoid, widest in the mid-region with rounded ends and gelatinous plugs, and 12 to 17 × 4.5 μm. Conidiomata were pycnidial, intermixed among ascocarps, variable in shape, dark brown, solitary or aggregated, ostiolate, and with long necks up to 1 mm. Pycnidial walls were pseudoparenchymatic, multicellular, and composed of many layers of brown compressed cells. Conidiogenous cells were hyaline, subglobose to cylindrical, and smooth, and holoblastic. Conidia were hyaline, unicellular, obovate, 6 to 12 (7.5) × 5 to 8 μm, slightly truncate at the bases, rounded at apices, guttulate, and provided a gelatinous envelope and apical appendage. Appendages were hyaline, tubular, smooth, and 3.0 to 4.5 × 0.5 μm. The fungus is homothallic because single ascospores and single conidia developed ascigerous states. The ascigerous state was identified as Guignardia psidii (1) and the anamorph as Phyllosticta psidiicola (1,2). Pathogenicity tests were conducted on detached fruits inoculated with monosporic cultures. Pathogenesis and symptom development only occurred when a mixture of mycelium, ascospores, and conidia was used as inoculum. The fungus was reisolated from symptomatic fruit tissues. To our knowledge, this is the first report of Guignardia psidii, an ascigerous state of Phyllosticta psidiicola from guava fruits in Venezuela. References: (1) B. A. Ullasa and R. D. Rawal. Curr. Sci. 53:435, 1984. (2) H. A. van der Aa. Page 95 in: No. 5, Stud. Mycol., 1973.

Ten biological or ecological characteristics of pathogens/diseases were used to quantitatively describe 34 soybean (Glycine max) fungal diseases in the United States. These characteristics included optimal temperatures for disease development, host ranges, characteristics of disease cycle, and the pathogens' survival capacity. Gower's general similarity coefficients for pairs of diseases were determined and used in principal coordinate analysis (PCoA) to project the diseases into a two-dimensional space, in which significant patterns were identified for some of the characteristic variables, e.g., means of pathogen dispersal. Similarity coefficients indicated that soybean rust (Phakopsora pachyrhizi) resembled soybean downy mildew (Peronospora manshurica) and Leptosphaerulina leaf spot (Leptosphaerulina trifolii). Cluster analysis with multiscale bootstrapping identified two major clusters with high significance level (P > 0.95). In a loose cluster (P = 0.86), soybean rust was grouped with brown spot (Septoria glycines), frogeye leaf spot (Cercospora sojina), Phyllosticta leaf spot (Phyllosticta sojicola), purple seed stain (Cercospora kikuchii), downy mildew, and Leptosphaerulina leaf spot. Estimated soybean yield losses in the United States from 1996 to 2005 and the geographical distribution information of the diseases in this cluster implied that the potential geographical distribution range of soybean rust may include most U.S. soybean production regions and that yield losses would be light in the north but moderate in the south if environmental conditions are conducive.

Leaf spot disease on the spider lily [Hymenocallis littoralis (Jacq.) Salisb.] continues to cause serious problems in China. To confirm the pathogen, the pathogenicity of isolates from diseased leaves was tested according to Koch’s postulates. The isolates were tentatively identified using morphological characteristics and confirmation was done by phylogenetic analysis of the translation elongation factor 1-alpha gene (TEF1), the actin gene (ACT), and internal transcibed spacer (ITS) sequences using neighbor-joining (NJ), maximum parsimony (MP), and Bayesian inference (BI) methods. The pathogen was identified as Phyllosticta hostae. Molecular analysis indicated very little diversity in the TEF1, ACT, and ITS gene. This is the first report of P. hostae causing leaf spot disease on spider lily in China.

The Southern corn leaf blight (SCLB) epidemic of 1970 devastated fields of T-cytoplasm corn planted in monoculture throughout the eastern United States. The epidemic was driven by race T, a previously unseen race of Cochliobolus heterostrophus. A second fungus, Phyllosticta zeae-maydis, with the same biological specificity, appeared coincidentally. Race T produces T-toxin, while Phyllosticta zeae-maydis produces PM-toxin, both host-selective polyketide toxins necessary for supervirulence. The present abundance of genome sequences offers an opportunity to tackle the evolutionary origins of T- and PM- toxin biosynthetic genes, previously thought unique to these species. Using the C. heterostrophus genes as probes, we identified orthologs in six additional Dothideomycete and three Eurotiomycete species. In stark contrast to the genetically fragmented race T Tox1 locus that encodes these genes, all newly found Tox1-like genes in other species reside at a single collinear locus. This compact arrangement, phylogenetic analyses, comparisons of Tox1 protein tree topology to a species tree, and Tox1 gene characteristics suggest that the locus is ancient and that some species, including C. heterostrophus, gained Tox1 by horizontal gene transfer. C. heterostrophus and Phyllosticta zeae-maydis did not exchange Tox1 DNA at the time of the SCLB epidemic, but how they acquired Tox1 remains uncertain. The presence of additional genes in Tox1-like clusters of other species, although not in C. heterostrophus and Phyllosticta zeae-maydis, suggests that the metabolites produced differ from T- and PM-toxin.

The health state of Ginkgo biloba L. and damage caused by microscopic fungi were evaluated over the 2010-2011 time period, in selected localities of Slovakia and Czechia. The trees were assessed and put into two categories of health. Trees in very good (category 1) or good vitality and health with no or only light damage (category 2). A total of seven species of microscopic fungi were identified from samples taken from branches, fruits, and leaves. The following fungal genera were detected: Epicoccum, Fusarium, Alternaria, Phomopsis, Cylindrosporium, Phyllosticta, and Cladosporium. This present study is the first report about microscopic fungi determined on G. biloba for Slovakia

Sowing seed material of33 species of herbs obtained in 1997-1999 from the Herb Seed-Testing Station, in Bydgoszcz were examined. Fungi were isolated using the method of artificial cultures on the mineral medium. Sixty seeds superficially disinfected and sixty undisinfected seeds were taken from each sample. Obtained single-spore cultures of the fungi grown on malt-agar or on standard medium were identified up to the species level. Fungi species belonging to the genus Fusarium were identified on the PDA and SNA, Aspergillus spp. and Penicillium spp. on the malt-agar and Czapek-Dox and Phoma spp. on the malt-agar, oat-meal-agar and cherry-agar. Mycological analyses showed that the superficial disinfection of seeds reduced by three times the number of isolates obtained. The fungi most frequently isolated from both the inside and the outside seed tissues were Botrytis cinerea, Phoma exigua var. exigua and species of Alternaria, Epicoccum, Fusarium, Penicillium, Phyllosticta, Rhizopus, Trichothecium.

Freckle disease of banana is caused by three closely related species of Phyllosticta, namely P. musarum, P. maculata and P. cavendishii. In this study, a high resolution melting (HRM) analysis assay was developed and its potential to identify these three fungal species is reported. The assay, which targets the ITS of the nuclear rDNA of the fungal species, generates three distinct melt profiles for the three Phyllosticta species. It is also able to distinguish a combination of up to three co-infecting species by generating a deviant melt curve. Thirty-five fungal cultures and infected herbarium leaf specimens, previously characterized using nucleotide sequencing as belonging to one of the three Phyllosticta species, were used for validation of the HRM analysis assay. The normalized curves generated differentiated all samples, with samples from each species correctly identified. The assay was further evaluated against 18 uncharacterized infected leaf specimens from various geographic locations and the results were verified by subsequent nucleotide sequencing. This HRM analysis assay allows rapid identification and differentiation of the three Phyllosticta species using a single primer pair in a one-step closed-tube system without labelled fluorescence probes. This novel assay format has potential for simultaneously identifying and differentiating other closely related species of plant pathogens, as well as the classification of infected historic specimens.

Guignardia citricarpa Kiely (anamorph Phyllosticta citricarpa Van der Aa), the causal agent of citrus black spot disease, is subject to phytosanitary restrictions in the EU and USA, such that consignments of citrus are rejected at import if citrus black spot is identified on inspection. Due to the variability of black spot symptoms, positive identification solely on the basis of visual inspection is difficult, especially when lesions lack pycnidia (fruiting bodies of the anamorph Phyllosticta citricarpa). As an aid to visual inspection of symptoms, we have developed a method for detection of G. citricarpa using loop-mediated isothermal amplification (LAMP) which can be used to confirm the presence of G. citricarpa in black spot lesions, including those lacking pycnidia. The LAMP assay can be used to test crude extracts prepared directly from lesions on fruit, and the entire test can be completed in less than 40 min, making it faster than previously described PCR-based methods for detection of G. citricarpa. The method is sufficiently simple to allow deployment of the test in the field, for example in the course of import inspections. Recent years have seen the description of a number of newly recognised species in the genus Phyllosticta that are associated with citrus. As new species emerge, and the taxonomy of the genus is resolved, it will be important to periodically re-evaluate the performance of DNA-based methods for detection of G. citricarpa, including the LAMP assay described here, such that the accuracy of diagnosis can be assured.

Polyamine biosynthesis inhibitors, DL-α-difluromethylornithine (DFMO) and DL-α-difluromethylarginine (DFMA) at concentrations of 1,0 and 3,0 mM greatly inhibited mycelial growth of Phyllosticta antirrhini on Czapek Dox Agar (CDA). Putrescine at the concentration of 1,0 mM completely reversed the inhibitory effect of DFMO but only partially that of DFMA. Both polyamine biosynthesis inhibitors at concentrations 1,0 and 3,0 mM applied preventively and curatively strongly inhibited the development of the pathogen on snapdragon leaves.

The initial infection stages of Phyllosticta maculata on banana were studied using scanning electron microscopy. Conidial germination on the banana leaf surface commenced within 3h postinoculation to produce a long and slender germ tube. The hyphae developed secondary branches and mostly grew randomly across the leaf surface. Appressoria were formed at the apex of the germ tubes within 18h postinoculation and were variable in shape. A layer of an extracellular matrix surrounded the appressoria at the pathogenhost interface. On the fruit surface, conidia germinated to produce predominantly swollen germ tubes which functioned as lateral appressoria together with some slender ones. These germ tubes were formed within 3h postinoculation. There was no stomatal penetration apparent on the leaf; instead, direct penetration through the cuticle with and without the formation of appressoria was observed. Cuticular degradation on the leaf surface was evident with a circular, darkened area around the point of penetration by hyphae or appressoria. The significant role of pycnidia and conidia in the epidemiology of the disease was further demonstrated in naturally infected leaf samples.

In the years 2001-2004, the occurrence of parasitic fungi of plants of the genera Betula and Salix growing in the Słowiński National Park was investigated. The plant species examined included B. pubescens, B. pendula, S. aurita, S. caprea, S. cinerea, S. fragilis, and S. repens. Plants of the genus Betula were affected by 9 species of parasiting fungi. In Poland, three of them (Microsphaera ornata var. europaea, Phyllactinia guttata, Melampsoridium betulinum) occur commonly, five (Asteroma leptothyrioides, Discula betulina, Fusicladium betulae, Phyllosticta betulina, Septoria betulina) are rare, and Septoria betulae-odoratae has not been recorded to date. Three species, Asteroma leptothyrioides, Fusicladium betulae, Phyllosticta betulina), were found on new plant hosts. Plants of the genus Salix were attacked by 8 species of parasiting fungi. Four of them (Melampsora allii-fragilis, M. caprearum, M. epitea, Uncinula adunca var. adunca) are common in Poland, four (Marssonina salicicola, Phyllosticta salicicola, Septoria salicicola, Trimmatostroma betulinum) rarely occur here. Uncinula adunca var. adunca, Marssonina salicicola, Phyllosticta salicicola, Septoria salicicola and Trimmatostroma betulinum were associated with the plant species not reported earlier to be their hosts.

Citrus is an economically important fruit crop in India. In December 2016, citrus black spot (CBS)-like symptoms were observed on Nagpur mandarin (Citrus reticulata), ‘Mosambi’ sweet orange, and Cutter Valencia (C. sinensis) trees in two orchards situated at Mohpa and Kachimet localities of Nagpur district, Maharashtra state (21.14 to 21.30°N, 78.82 to 79.02°E). Later symptoms were also noticed on Nagpur mandarin and Mosambi fruits in the fresh fruit market of Nagpur (also known as “Orange City”). Fruit symptoms included hard spot, red-brown spot, freckle spot, and virulent spot. To isolate the causal agent, fruit lesions were surface disinfested with 1% NaOCl and plated on potato dextrose agar (PDA) and oatmeal agar (OA). Fifteen single-spore cultures resembling those of the genus Phyllosticta were obtained. On PDA, the colonies had irregular margins, with numerous pycnidia, lined by a translucent zone of colorless submerged mycelium. On OA, a distinct yellow pigment was produced that diffused into the medium around the colony. Conidia (9.6 to 10.3 × 5.9 to 9.0 μm; average, 9.9 × 7.3 μm; n = 30) were hyaline, aseptate, ovoid with a flattened base surrounded by a hyaline matrix (0.8 to 1.1 μm; average, 0.9 μm; n = 30) and a hyaline appendage (6.6 to 13.6 μm; average, 8.8 μm; n = 30) on the rounded apex, corresponding to published descriptions of P. citricarpa (sexual morph Guignardia citricarpa) (Baayen et al. 2002). Leptodothiorella spermatial state formed in pure culture, and spermatia (4.8 to 7.9 × 0.8 to 1.3 μm; average, 7.0 × 1.0 μm; n = 30) were hyaline, dumbbell shaped to cylindrical, and both ends bluntly rounded. No sexual structures were observed. DNA was extracted from six representative isolates (CB1 to CB6) using a Qiagen DNeasy Plant Mini Kit. The nuclear ribosomal internal transcribed spacer (ITS) region (GenBank accession nos. MF000337 to MF000341 and MF062501) and the translation elongation factor 1-alpha gene (tef1) (MF000342 to MF000347) were amplified and sequenced using universal primer pairs ITS5/ITS4 and EF1-728F/EF2, respectively. These isolates shared 99 to 100% nucleotide sequence similarity (for both ITS and tef1) among themselves and had 99 to 100% homology with P. citricarpa ITS sequences from the United States (GenBank no. KC311457) and South Africa (KF709953) and with the P. citricarpa tef1 sequence of an Australian isolate (GenBank no. JF343602). The P. citricarpa-specific primers GCN and GCMR (Peres et al. 2007) produced a 300-bp band from the DNA extracts of fruit lesions and pure cultures but not from healthy citrus tissue DNA. To confirm pathogenicity, two isolates (CB1 and CB4) were inoculated into Mosambi sweet orange (six fruits for each isolate), as described by Rodrigues et al. (2013). After 30 days, all the inoculation sites showed early hard spot-like CBS symptoms. Control fruits remained symptomless. P. citricarpa was consistently reisolated from the fruit lesions and identified by morphology and ITS sequencing. Earlier, P. citricarpa was noted on Citrus medica leaves in Chennai, India (Kumaran et al. 2008), but there was no proof of identification and characterization of the species. To our knowledge, this is the first confirmed report of P. citricarpa causing CBS in two economically important Citrus species, C. sinensis and C. reticulata, in India. The disease is of great importance to the Indian citrus industry because it inflicts serious fruit blemishes and can cause severe yield reduction under heavy disease pressure.

Citrus is an important subsistence crop in Angola, consumed mainly as fresh fruit. In April 2014, fruit symptoms reminiscent of citrus black spot (CBS) consisting of depressed circular spots of about 5 mm in diameter with a light-brown to gray center and black margins surrounded by green rind tissue were observed on a ‘Valencia’ sweet orange (Citrus sinensis) orchard in Bembe, Uige Province, Angola, with a disease incidence of 47%. Dark brown pycnidia were present in fruit lesions, which often coalesced forming sunken blemishes. Symptomatic fruits from this orchard were surface disinfected with 0.5% NaOCl for 2 min. Small fragments from lesions were plated onto potato dextrose agar (PDA) amended with 0.5 g of streptomycin sulfate/liter and incubated for 15 days at 23°C in the dark. Fungal colonies were transferred to PDA and oatmeal agar (OA) and incubated for 30 days at 23°C with 12-h photoperiod for morphological examination. Colonies were black with irregular margins in PDA and surrounded by a yellow pigment in OA. Pycnidia in PDA were aggregated, globose, dark brown, and 210 µm in diameter. Conidia were 9 to 12 × 5 to 7 µm, hyaline, aseptate, guttulate, obovoid to ellipsoid with truncate base, a mucoid layer and apical appendage. Pycnidia and conidia in PDA or fruit lesions were morphologically similar to those of Phyllosticta (Wikee et al. 2013). The ITS1-5.8S-ITS2 region, partial TEF1-alpha region, and LSU were amplified and sequenced as per Wikee et al. (2013) from DNA extracted from the single-spore isolate IIA-GC003NA, obtained from a Valencia sweet orange fruit from Bembe (GenBank accession nos. KY457232, MF693404, and MF693405, respectively). The sequences had 100% identity with those of P. citricarpa (McAlpine) van der Aa (synonym Guignardia citricarpa Kiely) epitype strain CBS 127454 (Glienke et al. 2011) (GenBank accession nos. JF343583, JF343604, and KF206306, respectively). Laboratory pathogenicity tests were performed by injecting the albedo of 30 mature detached fruit of Valencia sweet orange with 100 µl of a suspension of 3.0 × 10⁴ conidia/ml of water of the isolate IIA-GC003NA (Perryman et al. 2014). Fruits treated with sterile distilled water were used as controls. Fruits were maintained in humid chambers for 40 days at 24 to 26°C with 12-h photoperiod, and those inoculated with the fungus developed depressed necrotic lesions after 35 days. Field pathogenicity tests were performed on 12- to 14-week-old Valencia sweet orange fruits covered by waxed paper bags. Leaf disks colonized by the fungus were placed onto the rind of 60 fruits (Baldassari et al. 2009). Sterile leaf discs were used as controls. Symptoms of a false melanose-type consisting of dark brown stipplings were observed after 86 days on fruit inoculated in the field. No symptoms were observed on control fruit in either experiment. P. citricarpa, identified as described above, was reisolated from lesions on inoculated fruit in all experiments, but not from control fruit. The disease was verified as CBS caused by P. citricarpa. To our knowledge, this is the first report of CBS, caused by P. citricarpa, in Angola. P. citricarpa is responsible for large economic losses worldwide, so further studies are needed to map its geographic distribution, population structure, and impact in Angola.

Cranberry fruit rot (CFR) is caused by many species of fungi, with the contribution of any given species to the disease complex varying among plantings of Vaccinium macrocarpon within a site, sites within regions, and among regions and years. This study assessed the morphological and molecular variability of five widespread CFR-causing fungi: Phyllosticta vaccinii, Coleophoma empetri, Colletotrichum acutatum, Colletotrichum gloeosporioides and Physalospora vaccinii. Although the majority of isolates had morphological characteristics consistent with published descriptions, some were atypical. For example, non-chromogenic isolates of C. acutatum were recovered from British Columbia and white isolates of Physalospora vaccinii were recovered in addition to the more common dark isolates. On the basis of sequence analysis of the ITS and large subunit rDNA (LSU), it appears that Phyllosticta vaccinii, C. empetri, C. gloeosporioides and C. acutatum are genetically uniform on cranberry in North America. This suggests the possibility that these fungal species were introduced to cultivated cranberries and concomitantly moved with planting material to new locations. In contrast, white isolates of Physalospora had ITS and LSU sequences distinct from those of their dark counterparts, with phylogenetic analyses suggesting that these isolates represent either different species or distinct members of highly divergent populations. Taxonomic placement of all species based on phylogenetic relationships was consistent with morphological placement, with the exception of Physalospora vaccinii. Unlike other Physalospora species, CFR isolates of Physalospora vaccinii were not allied with the Xylariomycetidae; instead, these fungi were members of the Sordariomycetidae. A deeper taxonomic analysis is needed to resolve this inconsistency in familial affiliation.

In a study of pathogenic fungi infecting Buxus sincia, an interesting Phyllosticta species was isolated. The morphological characteristics of this species, such as slow growing mycelia, large conidia each with a long flagellum tag on diagnostic media, plus phylogenetic analysis based on 16S rDNA ITS sequences indicated that the fungus is a distinct new species which is described.

Phyllostictine A is a powerful toxin produced by Phyllosticta cirsii , a potential mycoherbicide of Cirsium arvense . To support its potential use as a natural herbicide, toxin production has been studied using different media and cultural conditions. The toxin content in the crude extracts has been determined by using a HPLC method set up for this purpose. Furthermore, its phytotoxicity has been evaluated on tobacco protoplasts by flow cytometric analysis, and on C. arvense protoplasts, by fluorescence microscopy. The best cultural conditions found allowed to produce more than 28 mg ml −1 of toxin in culture filtrate. The pure metabolite proved to have rapid dose-dependant toxic effects on host and no-host plant protoplasts.

A severe outbreak of Phyllosticta leaf blight was observed on mondo grass (Ophiopogon japonicas) in Jinju, South Korea during 2013–2014. Symptoms initially appeared on chlorotic leaves, followed by blight and finally leaf death. DNA sequencing and phylogenetic analysis of the internal transcribed spacer rRNA gene region confirmed that the isolate was Phyllosticta ophiopogonis. Koch’s postulates were supported by pathogenicity tests conducted on healthy plants. Based on morphological characteristics, pathogenicity tests, and molecular analysis, the causal fungus was identified as P. ophiopogonis. To the best of our knowledge, this is the first report of leaf blight caused by P. ophiopogonis on mondo grass in South Korea.

Water spinach, a specialty vegetable and a member of the sweet potato family, is cultivated for Asian markets in California (United States) and Ontario (Canada). Foliar diseases of this vegetable observed in commercial greenhouses of Ontario in 1993 and 1994, as well as in greenhouses of California in 1998, were attributed respectively to Phyllosticta ipomoeae, Cercospora ipomoeae, and Pseudomonas syringae pv. syringae in the present study. In Ontario, C. ipomoeae infected less than 1% of plants, with less than 25% of the foliage affected, while Phyllosticta ipomoeae occurred on 100% of plants in some greenhouses, with leaf spotting affecting up to 25% of the foliage. In California, Pseudomonas syringae pv. syringae occurred on less than 25% of plants with up to 25% of the foliage affected. In Ontario, no virus was detected in eight suspect foliage samples while damage from vectors of plant viruses such as the green peach aphid (Myzus persicae) was minor and from Western flower thrips (Frankliniella occid...

If South African citrus exporters wish to retain their competitive edge in the European market and access new markets such as the United States of America, it is of quarantine importance to distinguish between the citrus black spot pathogen, Guignardia citricarpa, and the harmless endophyte, G. mangiferae. The endophyte is not a sanitary or phytosanitary concern. This paper describes the design of species-specific primers that are able to detect and distinguish between these two Guignardia species. Application of the primer set CITRIC1 and CAMEL2 in conjunction with the ITS4 primer yielded polymerase chain reaction (PCR) amplicons of approximately 580 bp and 430 bp for G. citricarpa and G. mangiferae, respectively. Results obtained with these primers are in accordance with sequence data, and repeated tests verified accuracy and sensitivity. A BLAST search revealed no matches other than G. citricarpa and G. mangiferae, and no positive PCR results were obtained with Colletotrichum gloeosporioides, which is the most common contaminant in black spot lesions. We are, therefore, able to distinguish G. citricarpa and G. mangiferae unequivocally using a PCR-based method. This method was further improved to directly isolate DNA from fruit lesions by means of the DNeasy Plant Mini Kit (Qiagen). This eliminates the prior need for culturing the slow-growing organism, thereby shortening the time required to one day to test for and verify the presence or absence of the pathogenic G. citricarpa in export consignments.

Samples of ripe fruit were taken at harvest from all eight commercial cranberry farms in Michigan over a 3-year period to determine the distribution and incidence of fruit rot diseases and the fungal pathogens associated with rotted fruit. Totals of 23, 33, and 28 beds were sampled in 1999, 2000, and 2001, respectively. Fruit rot incidence varied widely among beds and farms and ranged from 5 to 97% (mean 33.4%) in 1999, 1 to 91% (mean 26.3%) in 2000, and 1 to 67% (mean 12.8%) in 2001. Differences in fruit rot incidence were observed among cultivars, but rankings differed among farms. In general, cultivars Ben Lear, Bergman, and Pilgrim tended to have lower and Beckwith and WSU61 higher fruit rot incidence than other cultivars grown in the same location. Colletotrichum acutatum, Pestalotia vaccinii, and Phyllosticta vaccinii were the fungi most frequently recovered from rotted fruit. Fusicoccum putrefaciens, Phomopsis vaccinii, Physalospora vaccinii, Allantophomopsis lycopodina, Coleophoma empetri, and Botrytis cinerea were isolated occasionally in 1999. The isolation frequency of Physalospora vaccinii, Phomopsis vaccinii, and C. empetri increased markedly in 2000. Glomerella cingulata was first detected in 2001. Fusicoccum putrefaciens was most common in the northern and Glomerella cingulata in the southern growing areas. A comparison of sound and rotted fruit from selected beds showed that Phyllosticta elongata predominated in sound fruit, whereas G. cingulata predominated in rotted fruit.

A leaf spot disease of maize occurring in Brazil in the 1980s was described as being caused by the ascomycete Phaeosphaeria maydis (P. Henn) Rane. Payak and Renfro (imperfect form Phyllosticta sp.). Disease symptoms were dark-green water-soaked spots that later became necrotic lesions. There are no reports at present in the literature of re-infection by the fungus under controlled conditions, casting doubt on the true identity of the pathogen. In this study, cytological analyses of lesions at the initial stages did not detect the presence of fungal structures. Bacterial colonies with yellow pigmentation were isolated from the lesions, which reacted positively in hypersensitivity tests in tobacco plants. Maize plants were inoculated with the isolated bacteria. After 72 h incubation in a dew chamber, plants were transferred to a greenhouse, where they remained until evaluation. Typical symptoms of the disease were observed 5‐7 days after inoculation of plants, only on treatments inoculated with the bacteria. The bacterium was re-isolated, which suggests its involvement in the initial phases of disease. The bacterium was identified as Pantoea ananas (synonym Erwinia ananas).

Gymnosporangium dobrozrakovae Mitrophanova, Cylindrosporium arbuti Vien.Bourg., Phoma galbulorum Sacc. et Therry, Phyllosticta serratulae Kalymb.,Placosphaeria onobrychidis (DC.) Sacc., Coniothryrium juniperi Schwarzman, and Camarosporium kursanovii Mechtieva were collected for the first time in Turkey. Short descriptions of fungi are given with their collection sites.

Alternaria zinniae, a fungus causing leaf necrosis in Xanthium occidentale, a widespread noxious weed of Australian summer crops and pastures, produces toxic metabolites when grown in liquid culture. Extensive application of NMR techniques, HR, EIMS and X-ray analysis permitted the identification of brefeldin A (4H-cyclopent[f]oxacyclotridecin-4-one-1,6,7,8,9,1 1a,12,13,14,14a-decahydro-1,13-dihydroxy-6-methyl) and alpha,beta-dehydrocurvularin (4,5,6,7-tetrahydro-11,13-dihydroxy-4-methyl-2H-3-benzoxacyclododecin-2,10 (1H)-dione), two bioactive metabolites produced by a number of fungal species belonging to the genera Alternaria, Ascochyta Penicillium, Curvularia, Cercospora, and Phyllosticta, This is the first report on the isolation of these two phytotoxins from A. zinniae. The interesting semi-selective toxicity to X. occidentale is described here, and the possible use of fungus and toxins in integrated weed management programs is discussed. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.

From 1989 through to and including 1994 extensive premature defoliation of black locust ( Robinia pseudoacacia L.) was observed in a progeny test plantation in Greene County, in the Georgia Piedmont. During July 1991 and 1992, all observed trees suffered greater than 50% defoliation. Leaflets of black locust showing symptoms of leaf spotting began abscising as early as mid-June following wet springs. Onset and progress of defoliation was followed on 50 trees in two plots in 1993 and 1994. In both years, sample trees were cut at the base and allowed to regrow from sprouts. A protectant fungicide, chlorothalonil (Daconil WDG 1.5 g/l water) was applied to run-off weekly to one-half of the growing sprouts beginning 17 April through 22 August 1994 by backpack sprayer. Air temperature, relative humidity, rainfall, and leaf wetness were monitored. Abscission of unprotected leaflets in 1993, a dry, hot year, began in mid-July and averaged 36% by late August; abscission of unprotected leaflets in 1994, a wet, cool...

The population structure of Guignardia citricarpa sensu lato (anamorph: Phyllosticta citricarpa), a fungus of which strains pathogenic to citrus are subject to phytosanitary legislation in the European Union and the United States, was investigated. Internal transcribed spacer sequences revealed two phylogenetically distinct groups in G. citricarpa. This distinction was supported by amplified fragment length polymorphism analysis that also supported the exclusion of two isolates that had apparently been misclassified as G. citricarpa. On cherry decoction agar, but not on other media, growth rates of group I isolates were lower than those of group II isolates. Conidial dimensions were similar, but group I isolates formed conidia with barely visible mucoid sheaths, whereas those of group II formed conidia with thick sheaths. Cultures of isolates belonging to group I produced rare infertile perithecia, whereas fertile perithecia were formed by most isolates of group II. Colonies of isolates belonging to group I were less dark than those of group II, with a wider translucent outer zone and a lobate rather than entire margin. On oatmeal agar, exclusively group I isolates formed a yellow pigment. Group I harbored strains from citrus fruits with classical black spot lesions (1 to 10 mm in diameter) usually containing pycnidia. Group II harbored endophytic strains from a wide range of host species, as well as strains from symptomless citrus fruits or fruits with minute spots (

A survey was conducted over a 3-year period to determine the frequencies and distributions of fruit-rotting fungi in New Jersey cranberry beds. In the first 2 years of the study, Physalospora vaccinii and Glomerella cingulata were the most prevalent and widespread field-rotting fungi. In the third year, the frequency of G. cingulata declined markedly. Other species such as Coleophoma empetri, Phyllosticta vaccinii, and Phomopsis vaccinii were isolated at high frequencies from a limited number of locations. Storage-rotting fungi including Allantophomopsis cytisporea and A. lycopodina were isolated at low frequencies, but were widely distributed within the growing region. On sound fruit, a somewhat different profile emerged. Fungi such as Phyllosticta elongata, Alternaria spp., and Physalospora vaccinii were commonly isolated. In comparisons among different cranberry cultivars, no differences in the fungal profiles were seen. This was interpreted to indicate that if differences in fruit-rot resistance exist, they are likely to be general forms of resistance rather than fungal species-specific mechanisms.

The etiology of foliar blight of roselle and its effect on yield in the tropical forest of southwestern Nigeria was investigated. More than 40% of leaves of roselle plants in fields under continuous cultivation (endemic plots) were blighted by Phyllosticta hibiscini. However, no infection was found on roselle plants in fields never previously planted with roselle. Over 20% leaf yield loss and over 34% edible leaf loss were due to leaf blight. The mean marketable and biological yield loss of calyces in 1999 and 2000 were 35% and 38% respectively, while seed yield loss was 30% and 32%.

A leaf spot disease was found to be widespread in a little bluestem (Schizachyrium scoparium) nursery established at Mandan, ND, from plants collected in North Dakota, South Dakota and Minnesota. In 1984 through 1987, Phyllosticta andropogonivora was consistently isolated from leaves showing leaf spot symptoms. In 1986, the fungus was also isolated from native prairie little bluestem plants, from nursery and native prairie big bluestem (Andropogon gerardii) plants and from nursery sand bluestem (A. gerardii var. paucipilus) plants

Ramie, the vegetable fibre, is obtained from the stem of Boehmeria nivea (L.) Gaud, and is used in many textile products. It is grown in tropical, sub-tropical and temperate regions and the main countries where it is grown are China, Brazil and the Philippines. However, it is only a minor crop in terms of world trade. The diseases of ramie are discussed in relation to their occurrence, symptoms and control measures. The major and most widespread diseases are white fungus caused by Rosellinia necatrix, leaf spot caused by Cercosporo spp. and Phyllosticta spp., seedling rot caused by Rhizoctonia solani, cane rot caused by Macrophomina phaseolina and eye rot caused by Myrothecium roridum. A number of diseases of minor importance are also reviewed.

The conidia ofPhyllosticta lycopersici did not swell or produce germ tubes in distilled water alone. Carbon, nitrogen and PU43−were indispensible for germination and the germination rate was increased by the presence of Mg2+. Carbon and nitrogen were required for maximum spore swelling but germ tube formation required PO43− addition to carbon and nitrogen. A wide spectrum of sugars could serve as the carbon source for germination except arabinose and mannitol.

Different corn (L.) inbreds and hybrids with normal cytoplasm (N) and similar inbreds with Texas (Terns) and other male sterile cytoplasms were compared for their reaction to Phyllosticta yellow leaf blight. Considerable resistance was found in some of the corn inbreds and hybrids tested. The resistance was found to be influenced by both cytoplasmic and nuclear factors. Plants with Tcms cytoplasm were the most susceptible, while C, J, and R types of cytoplasm seemed highly resistant. The reaction of offspring derived from a cross between susceptible and resistant normal inbreds indicated existence of at least one dominant gene pair for resistance to yellow leaf blight.

SUMMARY 1A serious disease of the Arum Lily (Richardia africana) is described, which causes the formation of large brown blotches on all parts of the aerial shoot system. 2The cause of the disease is Phyllosticta Richardiae n.sp., a diagnosis of which is given. 3Suggestions are made for the control of this disease both under glass and in the open.

Twenty-six fungi were isolated from Stokes aster plants at Glenn Dale and Beltsville, Maryland in 1975 and 1976. Alternaria alternata, Phomopsis and Phyllosticta comprised 75% of the total isolates.

Citrus black spot, caused by Phyllosticta citricarpa, is characterized by fruit blemishes and premature fruit drop, resulting in significant economic losses in summer rainfall areas. The pathogen forms both conidia and ascospores during its life cycle. However, the occurrence of these spores and their contributions to infection of fruit in field conditions are not well understood. Our research using direct leaf litter monitoring and volumetric spore trapping in Queensland orchards revealed that pseudothecia and ascospores in leaf litter as well as trapped ascospores had low abundance, while pycnidia and conidia were highly abundant. Both P. citricarpa and endophytic Phyllosticta spp. were identified, with P. citricarpa being dominant. In replicated field trials, we determined that infection of Imperial mandarin fruit by P. citricarpa occurred from fruit set until week 20 of fruit development, with the key infection events taking place between weeks 4 and 16 in Queensland subtropical conditions. These results demonstrate that protecting fruit during weeks 4 to 16 significantly reduced P. citricarpa infection. We found no significant correlation between the disease incidence in fruit and P. citricarpa conidial abundance in leaf litter or ascospore abundance measured by volumetric spore trapping. Therefore, it is suggested that inoculum sources in the tree canopy other than those detected by spore trapping and direct leaf litter monitoring may play a major role in the epidemiology of citrus black spot. Improved knowledge regarding epidemiology of P. citricarpa and an understanding of propagules causing infection may aid in development of more effective disease management strategies.

In 1969 severe leaf blighting was observed in hybrid corn (Zea mays L.) trials. This blight was attributed to Phyllosticta sp. and was accompanied in later stages by both stalk rots [Diplodia zeae (Schw.) Lev. and Gibberella zeae (Schw.) Fetch] and European corn borers (Ostrinia nubilalis Hubner). In 1970 corn hybrids were affected by southern corn leaf blight (Helminthosporium maydis Nisik. and Miyake). Paired samples of diseased and relatively nondiseased plants were taken in both years, were fractionated, and were evaluated for quality components. The Phyllosticta sp.-stalk rot disease complex reduced dry matter yields, while both percent cell wall constituents (CWC) and acid detergent fiber (ADF) were significantly higher — and therefore cell solubles correspondingly lower in the diseased fractions compared to the nondiseased fractions. Similarly, nitrate-N (NO₃-N) levels were significantly higher in the diseased fractions compared to the nondiseased fractions. When all fractions were compared, there was no significant difference between diseased and nondiseased samples on the basis of crude protein or ᵢₙ ᵥᵢₜᵣₒ dry matter digestibility (IVDMD). In 1970 diseased fractions were significantly lower in percent crude protein and IVDMD and higher in percent acid detergent lignin, ADF, and CWC than nondiseased fractions.