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Citriculture has been one of the most important agricultural activities worldwide. Brazil is among the five major citrus producers in the world, together with China, the European Union (EU), the United States, and Mexico. Together, these five groups are responsible for about 50% of the global citrus fruit production and this industrial segment is responsible for generating direct and indirect jobs. However, several citric diseases such as citrus canker, huanglongbing, citrus variegated chlorosis, and citrus black spot have been associatedwith annual losses of tons of fruits and orange trees impacting the global economy for decades. Citrus canker is caused by theGram-negative bacteria Xanthomonas citri subsp. citri. and is associatedwith symptoms such as the formation of chlorotic rings in the leaves, stems, and fruits. Huanglongbing (HLB) is mainly associated with the Gram-negative bacteria Candidatus Liberibacter spp. and its main symptoms are the appearance of yellowish branches and deformed small leaves with yellowish spots. Citrus variegated chlorosis (CVC) is associated with the bacterium Xylella fast idiosa and causes chlorotic spots with irregular edges on leaves and deformation of newleaves. Citrus black spot (CBS) is caused by the fungus Phyllosticta citricarpa and generates lesions on fruits and reddish-brown leaf lesions. Since citrus is important for global agriculture, the current review addresses the main features of these important diseases includingtheir symptoms andtransmission, aswell as thediagnosis and control strategies that have been studied so far for application in the field. [ABSTRACT FROM AUTHOR]

Ophiopogon japonicus (Asparagaceae) is a perennial grass species which can be cultivated as an ornamental and medicinal plant. From April 2021 to September 2022, a serious leaf blight disease of O. japonicus was discovered in Rizhao City, Shandong Province, China. The initial disease symptoms were small yellow spots, finally developing as tip blight, often associated with many small, black, semi-immersed pycnidial conidiomata formed in lesions. To obtain isolates of the causal agent for this disease, samples were randomly collected from O. japonicus diseased leaves in Rizhao City. In total 97 Phyllosticta isolates were obtained from samples, and studied using morphological features and multilocus phylogenetic analyses of a combined dataset using the internal transcribed spacers (ITS), the 28S large subunit of ribosomal RNA (LSU), and partial translation elongation factor 1-alpha (tef), actin (act) and glyceraldehyde-3-phosphate dehydrogenase (gapdh) loci. Phylogenetically, these Phyllosticta isolates formed a clade in the P. concentrica species complex, and clustered with P. pilospora and P. spinarum. Morphologically, isolates in this clade differed from P. pilospora and P. spinarum by the size of conidiogenous cells and conidia, and the absence of an apical conidial appendage. As a result, these isolates were described as a novel species Phyllosticta rizhaoensis. Pathogenicity was confirmed using Koch's postulates, which showed that P. rizhaoensis could induce leaf blight symptoms on O. japonicus in China. [ABSTRACT FROM AUTHOR]

The most devastating disease that affects ginger production and productivity in Southwestern Ethiopia and lowers qualitative and quantitative rhizome yields is ginger leaf spot, which is caused by the pathogen Phyllosticta zingiberi. In Tepi, Southwestern Ethiopia, during the main cropping seasons of 2020 and 2021, a field experiment was carried out to assess the efficacy of several fungicides in managing epidemics of ginger leaf spot disease. The fungicides evaluated were Ridomil Gold MZ 68 WG (Metalaxyl-M), Ethiozeb 80% WP (Mancozeb), Shega 50 WP (Copper oxychloride), and Matico (Metalaxyl 8% + Mancozeb 64% WP). While the plot without spray is used as control. The results of the experiment indicated that among the different fungicides tested four times spray of Matico (Metalaxyl 8% + Mancozeb 64% WP) starting from the appearance of the disease on the field within 15 days intervals produced the lowest leaf spot disease severity of 10.2% followed by foliar spray with Mancozeb (Ethiozeb 80% WP) 16.2% first at disease appearance and then 3 times at 15 days intervals. Similarly, the highest yield of 16.3 t ha-1 was also obtained by foliar from the plot foliar spray of Matico (Metalaxyl 8% + Mancozeb 64% WP) which is followed by spraying with Mancozeb (Ethiozeb 80% WP) with a yield of 12.56 t ha-1. Therefore four times foliar spray of Matico @ 2.5 kg ha-1 is highly effective against leaf spot disease of ginger in southwestern Ethiopia.

Benzoin resin, produced by the native Indonesian trees Styrax sumatrana and Styrax benzoin, has been incorporated into medical practices to treat wounds, erythema, and many other conditions for centuries. Endophytic fungi that reside within medicinal plants have antimicrobial, antioxidant, and α-glucosidase inhibitory capacities, contributing to plant health and derivative products. In this study, we determined the antifungal, antioxidant, and α-glucosidase inhibitory capacities of endophytic fungal isolates from three different tissues (leaves, bark, and stems) of S. sumatrana and S. benzoin trees. The genera of fungal isolates were determined by phylogenetic analysis of internal transcribed spacer sequences. A total of 58 fungal isolates were classified into 15 different fungal genera from eight taxonomic orders--Hypocreales, Botryosphaeriales, Glomerellales, Diaphortales, Pleosporales, Eurotiales, Xylariales, and Mucorales--with a pattern of host species specificity. Among these isolates, Trichoderma sp. 6407 consistently exhibited high inhibition of the growth of plant pathogens Fusarium sp., Trichoderma viride, and Aspergillus niger. With respect to antioxidant activity, Phyllosticta sp. 6454 consistently showed 2,2-diphenyl-1-picrylhydrazyl inhibition (37.59 ± 0.05%), 2,20-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid)-based antioxidant activity (25.04 ± 0.27 mgTE/g), and α-glucosidase inhibitory activity (52.15 ± 10.08%). Neopestalotiopsis sp. 6431 was notably potent in 2,2-diphenyl-1-picrylhydrazyl inhibition (49.65 ± 0.80%), ferric reducing antioxidant power-based antioxidant activity (197.49 ± 8.65 mgTE/g), and α-glucosidase inhibitory activity (52.88 ± 4.93%). This study revealed that Trichoderma sp. 6407, Phyllosticta sp. 6454, and Neopestalotiopsis sp. 6431 exhibited antifungal, antioxidant, and α-glucosidase inhibitory activities. [ABSTRACT FROM AUTHOR]

Benzoin resin, produced by the native Indonesian trees Styrax sumatrana and Styrax benzoin, has been incorporated into medical practices to treat wounds, erythema, and many other conditions for centuries. Endophytic fungi that reside within medicinal plants have antimicrobial, antioxidant, and α-glucosidase inhibitory capacities, contributing to plant health and derivative products. In this study, we determined the antifungal, antioxidant, and α-glucosidase inhibitory capacities of endophytic fungal isolates from three different tissues (leaves, bark, and stems) of S. sumatrana and S. benzoin trees. The genera of fungal isolates were determined by phylogenetic analysis of internal transcribed spacer sequences. A total of 58 fungal isolates were classified into 15 different fungal genera from eight taxonomic orders—Hypocreales, Botryosphaeriales, Glomerellales, Diaphortales, Pleosporales, Eurotiales, Xylariales, and Mucorales—with a pattern of host species specificity. Among these isolates, Trichoderma sp. 6407 consistently exhibited high inhibition of the growth of plant pathogens Fusarium sp., Trichoderma viride, and Aspergillus niger. With respect to antioxidant activity, Phyllosticta sp. 6454 consistently showed 2,2-diphenyl-1-picrylhydrazyl inhibition (37.59 ± 0.05%), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid)-based antioxidant activity (25.04 ± 0.27 mgTE/g), and α-glucosidase inhibitory activity (52.15 ± 10.08%). Neopestalotiopsis sp. 6431 was notably potent in 2,2-diphenyl-1-picrylhydrazyl inhibition (49.65 ± 0.80%), ferric reducing antioxidant power-based antioxidant activity (197.49 ± 8.65 mgTE/g), and α-glucosidase inhibitory activity (52.88 ± 4.93%). This study revealed that Trichoderma sp. 6407, Phyllosticta sp. 6454, and Neopestalotiopsis sp. 6431 exhibited antifungal, antioxidant, and α-glucosidase inhibitory activities.

The European Commission (DG SANTE) requested the European Food Safety Authority (EFSA) (EFSA mandate M‐2017‐00137), to support and assist the EU Member States (MSs) in the preparation and design of plant pest surveys. The MSs selected Phyllosticta citricarpa as a pilot organism for developing survey guidelines. In this context, a grant agreement was established between MESDC‐Plant Protection Directorate (PPD) and EFSA for improving the crisis preparedness for P. citricarpa in the European Union. This report is the outcome of a cooperation project between the citrus growing EU MSs. In the context of EFSA's ongoing activities in plant health surveillance, two workshops were co‐organised by the Maltese Ministry for the Environment, Sustainable Development and Climate Change Plant Protection Directorate (MESDC‐PPD) and the European Food Safety Authority (EFSA), aiming at sharing, developing and improving, together with the MSs, a harmonised statistically sound and risk based survey approach for P. citricarpa. The proposed methodological framework provides practical toolsthat support the MSs from the survey preparation to the survey design enabling their integration in the MSs contingency plans for the organism, including the identification of common actions for the control, containment and eradication. Also, the European and Mediterranean Plant Protection Organization's (EPPO) contributed to the workshops with their expertise on diagnostic protocols and contingency planning. [ABSTRACT FROM AUTHOR]

Taxonomical re‐examination of the Phyllosticta species parasitic fungi on coniferous trees (Cupressaceae) in Japan was conducted based on current criteria, such as morphological and cultural characteristics, phylogenetic relationship and pathogenicity. Phylogenetic analyses revealed several clades composed of plant pathogens isolated from a specific host as well as clades composed of endophytic species isolated from various Cupressaceae trees. Each clade was recognized as a species from the morphological characteristics and other features, respectively. Five species of Phyllosticta sensu stricto were recognized, and two of them were newly recorded in Japanese mycoflora. Furthermore, new comibination P. pilospora and its epitype are proposed. The epitype and ex‐type strain are also proposed for P. cryptomeriae in this study. [ABSTRACT FROM AUTHOR]

At the request of the European Commission, EFSA prepared these specific guidelines to guide the surveyor through the design of statistically sound and risk‐based surveys for Phyllosticta citricarpa, integrating the key biological information. Based on examples, three different survey designs are simulated:(i) detection surveys to substantiate pest freedom, (ii) delimiting surveys to determine the boundaries of an infested zone, and (iii) buffer zone surveys to monitor a zone ensuring pest detection at low levels of prevalence.The first step of the survey design consists of setting the goals of the survey, characterising the host plant population and the methods used to identify the pest. All survey parameters are quantified taking into accountthe importance of the related assumptions. The more accurateand robust the information used for selecting and estimating the survey parameters, the more robust the conclusions of the survey will be. The second step of the survey design consists of the sample size (i.e. number of trees)calculation using the survey parameters as inputs of the proposed statistical tool (EFSA RiBESS+).The last step of the survey design is the allocation of the samples in the survey area which depends on the information available on the target population and risk factors. The robustness of the conclusions of surveys designed using the proposed approaches strongly depends on the survey preparation. The methodology proposed allows surveys to be compared across time and space, thus contributing to the harmonisation of the P.citricarpasurveys across the EU. The extremely flexible approach allows the surveys to be tailored to each specific situation in the Member States, taking into account the citrus tree distribution and available resources. The success of a good survey design relies on the technical aspects of the survey preparation and on the involvement of the risk managers. [ABSTRACT FROM AUTHOR]

The European Commission requested EFSA (M‐2017‐0137) to assist the Member States to plan annual survey activities of quarantine organisms using a statistically sound and risk‐based pest survey approach, in line with current international standards. Phyllostictacitricarpa is a Union quarantine pest and the causal agent of citrus black spot (CBS). It is not known to occur in the EU so special requirements for the import of its host plants and fruit from third countries are in place to prevent its introduction and spread. P. citricarpa produces asexual pycnidia and pycnidiospores on fruit lesions, twigs and leaf litter, but it can also reproduce sexually, giving rise to pseudothecia and ascospores, which are particularly important for long‐range dissemination. Most commercial citrus species are susceptible to CBS. Due to the variety of environments in which the fungus is currently distributed, all citrus‐growing areas in the EU are potentially suitable for the establishment of the pest. The main pathways for its introduction and spread include production, handling and transport of infected plants for planting or fruit. The goal of the visual examination is to detect the symptoms caused by P. citricarpa. Since symptoms are non‐specific and may be highly variable, visual examination should be followed by laboratory testing. Moreover, CBS has a long incubation period and infected fruit may still be asymptomatic at maturity. In this case, symptom induction methods or other early detection approaches (e.g. airborne spore traps or rain collectors for splash‐dispersed conidia) could be further explored. For symptomatic fruit, three mainmethods foridentifyingP. citricarpain the laboratoryare presented.Based on the analyses of the information on the pest–host plant system, the variousunits that are needed to design asurvey should be defined and tailored to the situation of each Member State. [ABSTRACT FROM AUTHOR]

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Citrus black spot (CBS) is caused by Phyllosticta citricarpa , which is regarded as a quarantine pathogen in certain countries. Pest risk assessments disagree on the risk of fruit as a pathway for introduction of the pest to new areas. Some countries accordingly regulate the movement of fruit from production regions where CBS occurs. Preharvest fungicide sprays are very effective in controlling CBS, but cannot consistently achieve complete control. The effect of postharvest treatments on CBS infections and on the reproductive ability of P. citricarpa in lesions that formed after these treatments was studied. Trials were conducted using naturally infected ‘Eureka’ lemon and Valencia orange fruit. Asymptomatic fruit were treated using commonly used packhouse sanitation and fungicide treatments, and cold storage (individually and combined), as well as alternative stand-alone treatments. After treatment, fruit were stored for 5 weeks (in the dark) at ambient temperature (20–22 °C) or −0.5–7 °C, whereafter they were incubated for a further 2 weeks at conditions conducive to expression of symptoms and formation of pycnidia. Individual treatments generally resulted in variable levels of control. The combination of packhouse treatments (including pre-packhouse drench with guazatine or propiconazole in combination with pyrimethanil, thiabendazole and 2,4-D; chlorine wash; dip treatment in imazalil; and brush application of a wax coating incorporated with imazalil, thiabendazole and 2,4-D) consistently showed moderate to high levels of control of CBS development from latent infections on lemons (32.4–43.4% for incidence and 61.6–68.3% for severity) and oranges (58.3–85.7% for incidence and 54.1%–88.8% for severity). However, cold storage subsequent to packhouse treatments (as is common shipping protocol) further improved the levels of control (44.0–58.3% for incidence and 78.1–82.5% for severity on lemons; 66.1–93.5% for incidence and 85.3–98.5% for severity on oranges). An average of 10% of new lesions on lemons and 15% on oranges formed pycnidia, indicating that P. citricarpa generally had a low reproductive capability in fruit lesions, which was in most cases further diminished by the combination of treatments followed by cold storage. [ABSTRACT FROM AUTHOR]

Summary: Terpene volatiles play an important role in the interactions between specialized pathogens and fruits. Citrus black spot (CBS), caused by the fungus Phyllosticta citricarpa, is associated with crop losses in different citrus‐growing areas worldwide. The pathogen may infect the fruit for 20–24 weeks after petal fall, but the typical hard spot symptoms appear when the fruit have almost reached maturity, caused by fungal colonization and the induction of cell lysis around essential oil cavities. d‐Limonene represents approximately 95% of the total oil gland content in mature orange fruit. Herein, we investigated whether orange fruit with reduced d‐limonene content in peel oil glands via an antisense (AS) approach may affect fruit interaction with P. citricarpa relative to empty vector (EV) controls. AS fruit showed enhanced resistance to the fungus relative to EV fruit. Because of the reduced d‐limonene content, an over‐accumulation of linalool and other monoterpene alcohols was found in AS relative to EV fruit. A global gene expression analysis at 2 h and 8 days after inoculation with P. citricarpa revealed the activation of defence responses in AS fruit via the up‐regulation of different pathogenesis‐related (PR) protein genes, probably as a result of enhanced constitutive accumulation of linalool and other alcohols. When assayed in vitro and in vivo, monoterpene alcohols at the concentrations present in AS fruit showed strong antifungal activity. We show here that terpene engineering in fruit peels could be a promising method for the development of new strategies to obtain resistance to fruit diseases. [ABSTRACT FROM AUTHOR]

Abstract: Following a request from the European Commission, the EFSA Panel on Plant Health performed a pest categorisation of Guignardia laricina, a well‐defined and distinguishable fungal species of the family Phyllostictaceae. The pathogen is regulated in Council Directive 2000/29/EC (Annex IAI) as a harmful organism whose introduction into the EU is banned. G. laricina is native to East Asia and causes a shoot blight disease of Larix spp. Major hosts of G. laricina are European larch (Larix decidua) and two North American larch species (Larix laricina (tamarack) and Larix occidentalis (Western larch)). Larix kaempferi (Japanese larch) is reported as susceptible. The only other host in nature is Douglas fir (Pseudotsuga menziesii), which is reported as an incidental host, but various other conifers have been reported as susceptible following artificial inoculation, including Picea abies. The fungus is not known to occur in the EU but could enter via plants for planting (including artificially dwarfed plants) and cut branches of Larix spp. It could establish in the EU, as hosts are present and climatic conditions are favourable. The pathogen would be able to spread following establishment by natural dissemination of ascospores and pycnospores and by human movement of infected plants for planting. Should the pathogen be introduced in the EU, impacts can be expected in larch forests, plantations and nurseries, leading to reduced tree growth and ecosystem service provision. The key uncertainties concern the current distribution and level of impacts in the native range of the pathogen. The criteria assessed by the Panel for consideration as a potential quarantine pest are met. As the pest is not present in the EU, not all criteria for consideration as a regulated non‐quarantine pest are met. [ABSTRACT FROM AUTHOR]

Leaf necrosis is a common fungal problem of plants. During a survey of Lahore, Dracaena Red Edge (Dracaena mariginata Lam.) and Sow thistle (Sonchus oleraceus L.) were infected with leaf spots. Pathogens isolation from the infected leaves of both plants was done followed by confirmation of Koch's pathogenicity postulates. Based on morphological and genetic characterization, Alternaria arborescens Simmons. and Phyllosticta aristolochiicola R.G. Shivas. were isolated from D. mariginata and S. oleraceus, respectively. In addition to isolation and identification, biological control of both pathogens was conducted using methanol extract of Cinnamon (Cinnamomum verum J. Presl.). All concentrations of extract suppressed the growth of both pathogens to variable extent. In case of A. arborescens, 0.5% concentration induced approximately 90% suppression in fungal growth. Contrastingly, P. aristolochiicola was least affected at lower concentrations of extract as only 4-10% arrest in fungal biomass production was recorded at 0.5-1.5% concentrations. However, 2.0% or more of the extract was most potent as fungal pathogens failed to grow at these concentrations. Therefore, Cinnamon extract was considered more effective in controlling A. arborescens than P. aristolochiicola. Further, studies are required to identify active antifungal compounds in Cinnamon crude extract against the target pathogens. [ABSTRACT FROM AUTHOR]

The period of citrus black spot (CBS) control used in South Africa (SA) and Australia, from October to January or February, has not been as effective in São Paulo (SP), Brazil. This study aimed to evaluate different periods of protection and determine the critical period for CBS control in SP. A field trial was carried out for two seasons in a mature Valencia sweet orange orchard located in Mogi Guaçu, SP. Spray programs with a total of 60. 100, 140, 180, and 220 days of fruit protection (DFP) were evaluated. CBS symptoms and fruit drop decreased exponentially as the length of the period of protection increased. The reductions in CBS intensity and crop loss with these programs ranged from 34 to 96 and 50 to 77%, respectively. The programs with 180 and 220 DFP, which protected the fruit from September to March and May, showed the highest cost benefit. The critical period needed for CBS control in SP is longer than that in SA and Australia The results obtained with the present study are helpful for scheduling a more efficient and rational program for CBS control not only in SP but also in other tropical and subtropical regions with similar weather conditions. [ABSTRACT FROM AUTHOR]

Phyllosticta ampelicida causes black rot disease of Vitis spp. Genetic homogeneity of pathogen populations was investigated by analyzing the number of haplotypes present in infected samples from Europe and America. The fungus was identified from an analysis of the internal transcribed spacer (ITS) 1-ITS2 region, and partial sequences of (3-tubulin and calmodulin genes. The analysis of nuclear microsatellites applied to strains from Vitis spp. confirmed the existence of a high degree of genetic variability in the fungal populations, revealed four subpopulations, and showed that strains from America are distinct from the European ones. Furthermore, toe results obtained by landscape genetics showed that there were different introductions of the pathogen in the main vine areas of Europe, confirming what was observed in the first reports of the disease. The genetic variability of the fungus revealed by this study confirms the ability to generate new haplotypes by sexual reproduction. The difference found between the European populations and the American one confirms that the pathogen originated from America. [ABSTRACT FROM AUTHOR]

Isolation of ginger (Zingiber officinale) leaf spot pathogen form the UBKV farm field was done in the laboratory. The isolated pathogen was identified as Phyllosticta zingiberi on the basis of morphological characters as documented in taxonomic keys. The microscopic observation revealed that the pycnidia were globose to sub-globose with dark brown colour measuring 124.16 μm × 2.35 μm in average. The pycnidio spores were hyaline, oval to bullet shaped, monoguttulate measuring 4.02 μm × 2.35 μm in average. Among the different media tested for growth highest growth was recorded in Oat meal agar (26.44 cm2) followed by malt extract agar (24.04 cm2) which was statistically at par. The temperature of 25°C favoured maximum growth (24.20 cm2). However, higher sporulation was observed in 30°C. Among the different carbon source tested, mannitol supported the highest growth of the pathogen (27.67 cm2). [ABSTRACT FROM AUTHOR]

Citrus black spot (Phyllosticta citricarpa) causes fruit blemishes and premature fruit drop, resulting in significant economic losses in citrus growing areas with summer rainfall across the globe. The mating type locus of P. citricarpa has recently been characterized, revealing the heterothallic nature of this pathogen. However, insight into the occunence of mating and the impact of completing the sexual cycle of P. citricarpa was lacking. To investigate the occurrence and impact of sexual reproduction, we developed a method to reliably, and for the first time, produce ascospores of P. citricarpa on culture media. To demonstrate meiosis during the mating process, we identified recombinant genotypes through multilocus genotyping of single ascospores. Because the process of fertilization was not well understood, we experimentally determined that fertilization of P. citricarpa occurs via spermatization. Our results demonstrate that P. citricarpa is heterothallic and requires isolates of different AMTidiomorphs to be in direct physical contact, or for spermatia to fulfdl their role as male elements to fertilize the receptive organs, in order to initiate the mating process. The impact of mating on the epidemiology of citrus black spot in the field is discussed. [ABSTRACT FROM AUTHOR]

Ginger (Zingiber officinale Roscoe) is an important spice crop in India, which is also one of the leading producer and exporter of ginger in the world. During cultivation, the crop is severely infected by various diseases of them soft rot, yellows, Phyllosticta leaf spot, storage rot, bacterial wilt, mosaic, chlorotic fleck are important. These diseases reduce the potential yields drastically. The geographical distribution, losses, symptoms, causal organism, disease cycle, epidemiology and host resistance, cultural, biological, chemical and integrated management of above mentioned diseses have been discussed in the present paper. [ABSTRACT FROM AUTHOR]

Citrus black spot disease, caused by the phytopathogen Phyllosticta citricarpa, depreciates the market value of citrus fruits and prevents their exportation to disease-free regions. It may also reduce the productivity of citrus fruit orchards. To identify an alternative to conventional disease control measures, isolates of Diaporthe terebinthifolii, active against P. citricarpa, were selected from an endophytic fungal population of Schinus terebinthifolia leaves. Different culture media were screened to identify the culture medium that afforded the most efficient production of biologically active extracts. A particular fraction (fraction VI) of the extract completely protected orange leaves by inhibiting the germination of P. citricarpa conidia with a minimum inhibitory concentration of 0.003 µg.mL-1. The active constituents in D. terebinthifolii extract fractions were identified by gas chromatography coupled to mass spectrometry as verbanol, phenylethyl alcohol, verbenyl acetate and methyl hexadecanoate. The results obtained strongly suggest the existence of a synergistic effect among the metabolites produced. Thus, these fungal metabolites could be used to control the CBS disease. As the asexual spores of P. citricarpa play an important role in fruit lesion development and disease dispersion, fungal extracts that inhibit the spore germination can be used as an effective alternative for directional disease control. [ABSTRACT FROM AUTHOR]

Citrus black spot (CBS) is a disease caused by the fungus Phyllosticta citricarpa that is associated with significant yield losses. The pathogen forms airborne ascospores that are collected in dead fallen leaves as well as waterborne conidia that are common in lesions on mature fruits and occasionally in leaves and dead twigs. In Brazil, cultural management combined with the application of systemic, protective fungicides is a practice adopted to reduce both inoculum sources. Nevertheless, the removal of mature infected fruits, dead twigs, and dead fallen leaves has not been shown to reduce the extent of disease. Moreover, the increasing use of fungicides has led to the selection of resistant strains, as well as human health concerns. To better understand this pathosystem and how the pathogen overcomes control measures currently in use, we evaluated branches at different growth stages in the field, the viability of the pathogen in detached branches, and the possibility of plant colonization through leaves. We observed that living branches are a reservoir for this pathogen and that once the branches senesce, the pathogen can persist up to 45 days, able to contaminate other plant parts. On inoculated leaves, we observed only a one-point latent infection, without signs of colonization. We also developed a faster protocol to produce pycnidia of the pathogen using autoclaved branches as a substrate, which proved useful for testing alternative compounds to control P. citricarpa. These data may be useful in the search for new effective control measures and their targets. [ABSTRACT FROM AUTHOR]

Fungal growth inhibition on solid media has been historically measured and calculated based on the average of perpendicular diameter measurements of growth on fungicide amended media. We investigated the sensitivity of the calculated area (DA) and the measured area (MA) for assessing fungicide growth inhibition of the ascomycete, Phyllosticta citricarpa on solid media. Both the calculated, DA and the actual measured area, MA were adequate for distinguishing significant treatment effects of fungicide on fungal growth, however MA was more sensitive at identifying significant differences between the controls and fungicide concentrations below 5 ppm. [ABSTRACT FROM AUTHOR]

A study on the identification and spread of harmful flora on lemon balm (Melissa officinalis) in the region of Dobroudzha was conducted during the period 2015 - 2016. The research established that the percentage of the diseased plants (in a plantation of 1 ha) was 9.42%, while the index of the infected leaves was 19.25%. Small, irregular, light brown to necrotic spots with a darker edge were formed on the leaves. The spots were randomly scattered over the whole lamina. On the branches were found elongated light brown spots, resulting in the formation of shells as well as partial or complete drying of the plants. A pycnidia fungus was isolated from the leaves and branches with typical symptoms. The pathogenicity of the isolates was proven. The morphological and cultural characteristics were tested. On this basis the pathogen Phyllosticta decidua Ellis et Kellermann was identified. The fungicidal activity of 6 products with a different active base as well as of two biological extracts was tested in vitro. [ABSTRACT FROM AUTHOR]

Romania, Verbascum phlomoides known as wooly mullein or orange mullein is considered to be a plant used in traditional medicine as tea or decoct from flowers and leaves. As tea it is used to ameliorate on short time some pulmonary affections as cough acute and chronic bronchitis, cold, flu, bronchial catarrh, pneumonia, pleurisy, pulmonary congestion, angina, laryngitis, tracheitis, hoarseness and even tuberculosis. As decoct it is mentioned to help as emollient to ameliorate and specially in the history it was mentioned by antiques Greek physicians to cure some affections as there are expectoration, asthma, neurological disorders and some injuries. During the researches carried out on medicinal plants pathogens from the wild flora of the south-western part of Romania it was found on Verbascum phlomoides plants on different populations some leaf spots that was suspected to be produced by a leaf pathogen . Later on laboratory work it was determined that the leaf pathogen that cause the spots on the leafs was Phyllosticta verbasicola. In the present paper there are facts about the disease incidence on the previous mentiond area. First we determine in three parts of the area of interest some significant populations of Verbascum phlomoides concentrated on small areas. All this areas has as common point that they are situated near the Nera stream but on higher ground and on meadow sandy soil. There are a lot of Verbascum phlomoides plants on the Nera Canyon but there are small groups of 1- 6 plants there was hard to find places where the river medow was large enough to find more than five of this mullein groups. During the last years we learned that this pathogen was always present on mullein plants with different but since now it doesn't produce lethal attacks. In the present paper there are data about fungus Phyllosticta verbasicola attack parameters on the reference area. [ABSTRACT FROM AUTHOR]

Phyllosticta citricarpa, the citrus black spot pathogen, was first identified in Florida in March 2010. Subsequently, this pathogen has become established in Florida but can be easily confused with the endemic nonpathogenic citrus endophyte P. capitalensis. In this study, the mating-type (MAT) loci of P. citricarpa and P. capitalensis were identified via draft genome sequencing and were characterized at the structural and sequence levels. P. citricarpa was determined to have an idiomorphic, heterothallic MAT locus structure, whereas P. capitalensis was found to have a single MAT locus consistent with a homothallic mating system. A survey of P. citricarpa isolates from Florida revealed that only the MAT1-2 idiomorph existed in the Floridian population. In contrast, isolates collected from Australia exhibited a 1:1 ratio of MAT1-1 and MAT1-2 isolates. Development and analysis of simple sequence repeat markers revealed a single multilocus genotype (MLG) in the Floridian population (n = 70) and 11 MLG within the Australian population (n = 24). These results indicate that isolates of P. citricarpa from Florida are likely descendent from a single clonal lineage and are reproducing asexually. The disease management focus in Florida will need to be concentrated on the production and dispersal of pycnidiospores. [ABSTRACT FROM AUTHOR]

The in vitro and in vivo control of Phyllosticta citricarpa (citrus black spot, CBS) on citrus fruits was evaluated using 14 essential oils (EOs) extracted from Uruguayan native plants. In vitro, volatile components of Chenopodium ambrosioides completely inhibited fungal growth. The dilution agar test showed that fungus reproduction was completely inhibited by Conyza bonaerensis essential oil (EO). The other 12 EOs tested showed high inhibition after 10–15 d, presenting fungistatic effects. In vivo, assays were performed on fruit of lemon [ Citrus limon (L.) Burm] and Valencia orange [ Citrus sinensis (L.) Osbeck] in order to evaluate the effects of liquid and volatile EO phases on reproduction. Typical lesions of CBS without reproductive structures were exposed to Ch. ambrosioides and C. bonaerensis EOs for 20 d at 27 °C and cycles of 16 h light and 8 h dark. The volatile components of Ch. ambrosioides were able to control 100% of P. citricarpa reproduction in orange and lemon fruit. The growth of other fungi such, as Colletotrichum gloeosporoides and Fusarium sp., was also inhibited. Nevertheless, the liquid phase was not effective to control the pathogen. In another test, carton boxes with 20 fruits, each presenting typical CBS symptoms, but without the presence of reproductive structures, were exposed to 0.01 and 0.05% of Ch. ambrosioides EO (w/v). The fruits were stored at 5 °C for 20 d and then kept for 7 d at room temperature. A 40% reduction of reproduction was observed in citrus fruit exposed to 0.05% of EO. GC–MS analysis of EOs showed that Ch. ambrosioides EO was composed of 76% monoterpene compounds (49 and 27% of oxygenated and hydrocarbons, respectively), while C. bonaerensis EO presented 17% monoterpenes and 10% sequisterpenes. [ABSTRACT FROM AUTHOR]

Phyllosticta citricarpa is the epidemiological agent of Citrus Black Spot (CBS) disease, which is responsible for large economic losses worldwide. CBS is characterized by the presence of spores (pycnidiospores) in dark lesions of fruit, which are also responsible for short distance dispersal of the disease. The identification of genes involved in asexual reproduction of P. citricarpa can be an alternative for directional disease control. We analyzed a library of mutants obtained through Agrobacterium tumefaciens transformation system, looking for alterations in growth and reproductive structure formation. Two mutant strains were found to have lost the ability to form pycnidia. The flanking T-DNA insertion regions were identified on P. citricarpa genome by using blast analysis and further gene prediction. The predicted genes containing the T-DNA insertions were identified as Spindle Poison Sensitivity Scp3 , Ion Transport protein, and Cullin Binding proteins. The Ion Transport and Cullin Binding proteins are known to be correlated with sexual and asexual reproduction in fungi; however, the exact mechanism by which these proteins act on spore formation in P. citricarpa needs to be better characterized. The Scp3 proteins are suggested here for the first time as being associated with asexual reproduction in fungus. This protein is associated with microtubule formation, and as microtubules play an essential role as spindle machinery for chromosome segregation and cytokinesis, insertions in this gene can lead to abnormal formations, such as that observed here in P. citricarpa . We suggest these genes as new targets for fungicide development and CBS disease control, by iRNA. [ABSTRACT FROM AUTHOR]