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We have constructed two intra-molecularly shuffled promoters, namely S100 and D100. The S100 recombinant promoter (621 bp) was generated by ligation of 250 bp long upstream activation sequence (UAS) of Strawberry vein banding virus (SV10UAS; − 352 to − 102 relative to TSS) with its 371 bp long TATA containing core promoter domain (SV10CP; − 352 to + 19). Likewise, 726 bp long D100 promoter was constructed by fusion of 170 bp long UAS of Dahlia mosaic virus (DaMV14UAS; − 203 to − 33) with its 556 bp long core promoter domain (DaMV4CP; − 474 to + 82). S100 and D100 promoters showed 1.8 and 2.2 times stronger activities than that of the CaMV35S promoter. The activity of the promoters is comparable to that of the CaMV35S2 promoter. Transcript analysis employing qRT-PCR and histochemical assays supported the above findings. Abscisic acid and salicylic acid induce the activity of the D100 promoter. Leaf protein obtained from Nicotiana tabacum plant expressing NSD2 gene (Nigella sativa L. defensin 2) driven by the D100 promoter showed antifungal activity against Alternaria alternata and Phoma exigua var. exigua and antibacterial activity against Pseudomonas aeruginosa and Staphylococcus aureus. Strong S100 and D100 promoters have potential to become efficient candidates for plant metabolic engineering and molecular pharming.

Pathogenesis-related (PR) proteins play important roles in plant defense response. However, functional investigation of PR10 genes is still limited and their physiological roles have not been conclusively characterized in biological processes of conifer trees. Here, we identified multiple novel members in the western white pine (Pinus monticola) PmPR10 family by bioinformatic mining available transcriptomic data. Phylogenetic analysis of protein sequences revealed four PR10 and two PR10-like clusters with a high synteny across different species of five-needle pines. Of 10 PmPR10 genes, PmPR10-3.1 was selected and expressed in Escherichia coli. The purified recombinant protein exhibited inhibitory effects on spore hyphal growth of fungal pathogens Cronartium ribicola, Phoma exigua, and Phoma argillacea by in-vitro anti-fungal analysis. Genetic variation analysis detected a total of 21 single nucleotide polymorphisms (SNPs) within PmPR10-3.1 in a collection of P. monticola seed families. A nonsynonymous SNP (t178g) showed significant association with relative levels of quantitative disease resistance (QDR), explaining about 8.7% of phenotypic variation as the peak value across all SNPs. Our results provide valuable insight into the genetic architecture underlying P. monticola QDR and imply that PmPR10-3.1 may function as an important component in conifer basal immunity for non-specific resistance to a wide spectrum of pathogens.

Fungal pathogens destruct the quality and quantity of tomato production and cause health hazards to the consumers as well as economic loss to the traders. This study was carried out to identify some fungal diseases associated with post-harvest deterioration of stored tomato fruits in three vegetable markets of Lagankhel, Balkhu and Kalimati of Kathmandu Valley. The samples were collected from selected sites in three separate trials and cultured in Potato Dextrose Agar. During investigation, 16 species belonging to 15 genera of fungi were identified. They were Alternaria alternata, A. solani, Aspergillus niger, Botrytis cinerea, Cladosporium fulvum, Colletotrichum truncatum, Curvularia tetramera, Fusarium oxysporum, Geotrichum candidum, Mucor mucedo, Penicillium notatum, Phytophthora infestans, Phoma exigua, Pullularia pullulans, Pythium aphanidermatum and Rhizopus stolonifer. These were responsible for 15 different diseases of Alternaria fruit rot, Anthracnose, Black mold rot, Botrytis Bunch Rot, Damping off/ fruit rot, Drechslera mold, Fusarium rot, Mucor rot, Penicillium rot, Phoma blight, Phytophthora rot, Rhizopus rot, Russet, Scab and Sour rot. The presence of these fungi and corresponding rot diseases on stored tomato indicate the need for management of fungi, farm sanitation and improved market in order to prevent field-to-storage transmission of pathogens.

Goal. To establish the spread of the latent form of the phomosis pathogen in the western region of the Forest-Steppe zone and to study the possibility of crop protection through the use of biofungicides. Methods. In the process of work used laboratory (cultivation of pathogens) and field (analysis, processing of tuber material). Results. The results of research conducted during 2019—2020 to detect latent infection of phomosis rot of potatoes in the western part of the forest-steppe zone of Ukraine (Zakarpattia, Chernivtsi, Ivano-Frankivsk regions) are presented. Within two years, the highest damage to tubers by latent phomosis infection was observed in varieties Yavir and Vodogray in the Ukrainian Carpathians (Ivano-Frankivsk region, Verkhovyna district, Bystrets village; Zakarpattia region, Mizhhirya district, Maidan village; Zakarpattia region, Rakhiv district, Yasinya village; Chernivtsi region, Vyzhnytskyi district, Berehomet village), which reached 25—33 and 21.0—23.0%, respectively. In the plain zone of Chernivtsi region (Hertsaiv district, Bukivka village; Novoselytsia district, UkrNDSKR IZR) a significantly lower percentage of tuber lesions with a latent form of the disease was observed. The minimum rates of tuber damage, both latent form of phomosis and with existing external signs, were observed in the variety Slovyanka and were in the plain zone 4.5—5.5% and 7.0—8.0 in the mountain. When treating tubers with biofungicides, the least pathogen tuber damage was observed in the variants using Trichodermin-Bio, PhytodoDoctor and Planriz, where the number of infected tubers was 10.0, 11.0 and 12.5%, respectively. In the control variant, the percentage of affected tubers with latent form of phomosis was 2.1—3.2 times higher than in the experimental ones. The effectiveness of biofungicides was greatest when using Trichodermin-Bio and PhytoDoctor and was 68.3 and 65.1%, respectively. Less effective drug against the latent form of phomosis, compared with other options was Hetomic, where its technical efficiency was 52.4%. Conclusions. The causative agent of phomotic rot of potatoes (Phoma exigua var. Exigua) in latent form is a widespread pathogen in the western part of the Forest-Steppe zone. To limit the spread of latent infection of phomos, biological drugs Hetomik (0.4 kg/ha) were used, Gaupbsin (5 l/t), Planriz (2 l/t), Trichodermin-Bio (2 l/t), PhytoDoctor (0.3 l/t), which helped to reduce the damage to the tubers by a latent form of the disease by 2.1—3.2 times compared to the control.

The genus Phoma is one of the dominant groups of fungi that are widely distributed in numerous ecological niches. Up to now, more than 200 species are recognized in Phoma, making it one of the biggest fungal genera. Many of them are phytopathogens of major significance on a wide range of crops worldwide. They cause extremely harmful diseases on vegetables of different families. Phoma terrestris (pink root of onion) (Alliaceae), Phoma apiicola (Phoma crown and root rot of celery), Calophoma complanata (Syn. Phoma complanata) (Phoma canker of parsnip) (Apiaceae), Phoma betae (blackleg of beet) (Amaranthaceae), Plenodomus lingam (Syn. Phoma lingam) (blackleg/Phoma leaf spot/stem canker of beans) (Brassicaceae), P. cucurbitacearum (gummy stem blight, and black rot of cucurbits) (Cucurbitaceae), Peyronellaea pinodella (Syn. Phoma pinodella) (root and foot rot complex and ascochyta blight of peas) (Fabaceae), Boeremia exigua (Syn. Phoma exigua) (Phoma basal rot of lettuce) (Asteraceae), and Remotididymella destructiva (Syn. Phoma destructiva) (Phoma blight/Phoma rot of tomato) (Solanaceae) are known to be the most prevalent species of pathogens on vegetables. While diseases caused by these pathogens are primarily field diseases, a few are known to cause spoilage of vegetables in storage, such as Boeremia exigua var. exigua or foveata (Syn. Phoma exigua var. exigua or var. foveata) (gangrene of potato), Phoma cucurbitacearum (black rot of cucurbits), Phoma apiicola (crown and root rot of celery), Calophoma complanata (Syn. Phoma complanata) (canker of parsnips), and Phoma betae (blackleg of beet). Diseases develop through soil-borne, seed-borne, and aboveground infections. Although a few general reviews on the fungal diseases of different crops are available, no comprehensive review has been compiled on the diseases of vegetables caused by Phoma spp. The information illustrated in the chapter may help improve the basic understanding of the pathological and management aspects of various fields and postharvest diseases of vegetables caused by Phoma spp.

This study was designed to prepare silver, zinc and gold nanoparticles (NPs), AgNPs, ZnNPs and AuNPs, by biosynthesis technique using methanolic extract of Rhanterium epapposum flowers using AgNO3, Zn (CH3CO2)2 and HAuCl4·3H2O as starting materials. The physical properties of the formed NPs were characterized by ultraviolet spectroscopy (UV), X-ray diffraction (XRD), transmission electron microscopy and Fourier transformed infrared spectroscopy (FTIR). The results revealed that, AgNPs were homogeneous and spherical in shape, with average diameter 16.3 nm. While, ZnNPs were approximately triangle and hexagonal shaped, with average diameter 23.5 nm. Most of the synthesized AuNPs were spherical in shape with average diameter 17.9 nm. The antifungal activity of different concentrations of the formed AgNPs, ZnNPs and AuNPs was tested against two human pathogens: Candida albicans and Aspergillus melleus and one plant pathogenic fungus: Phoma exigua, using agar diffusion assay. The best results recorded by 120 μg/ml AgNPs against the human pathogen: C. albicans where the inhibition zone was 23.5 mm. Additionally, the cytotoxicity of the tested NPs was evaluated against Breast adenocarcinoma (MCF-7), Hepatocellular carcinoma (HepG-2) and colorectal carcinoma (HCT 116) human cell lines. The most toxic was AuNPs where the IC50 against MCF-7, HepG2 and HCT116 was 55.02, 66.44 and 169.87 μg/mL respectively.

SUMMARY Comparisons of the saprotrophic fungi isolated from ash (Fraxinus excelsior L.), birch (Betula spp.), hazel (Corylus avellana L.), pedunculate oak (Quercus robur L.), sessile oak [Q. petraea (Mattuschka) Liebl.] and sycamore (Acer pseudoplatanus L.) leaf litters from three woodlands exposed to low, medium and high levels (c. 0 0-> 0 060 ,ul '1) of sulphur dioxide (SO2) showed that the composition of the fungal communities differed between sites. Fumigation of angiosperm tree leaf litters from the least and the most polluted site with environmentally-realistic concentrations (0 010-0 030 l l-1) of SO2 for 16-68 wk in an open-air field-fumigation experiment resulted in marked changes in the composition of the fungal communities in the leaf litters, comparable with differences found between the woodland sites. Cladosporium spp., Epicoccum nigrum Link, Fusarium spp. and Phoma exigua Desm. were less commonly isolated from leaf litters exposed to SO2, whereas Coniothyrium quercinum Sacc. var. glandicola Grove, Cylindrocarpon orthosporum (Sacc.) Wollenw. and Penicillium spp. were more frequently isolated from fumigated litters. However, few differences could be detected in the response to S02 of the mycofloras of leaf litters originating from different woodland sites. In general, S02 did not affect the total extent of fungal occupancy of the microsites in the litter, as fungal species which decreased in abundance on exposure to the gas appeared to be replaced in the litter by other species more tolerant to the gas. SO2 therefore appeared to be selectively toxic to saprotrophic fungi isolated from these litters.

summary Ash (Fraxinus excelsior L.), birch (Betula spp.), hazel (Corylus avellana L.), sessile oak [Quercus petraea (Mattuschka) Liebl.] and sycamore (Acer pseudoplatanus L.) leaf litters from a virtually non-polluted and a heavily sulphur dioxide (SO2)-polluted woodland were fumigated with environmentally-realistic concentrations (0.010–0.030μl l−1) of SO2 for 16–68 wk in an open-air field-fumigation experiment. Fumigation inhibited the respiration (CO2 evolution) and decomposition rates of the leaf litters. However, there were few differences in the responses between leaf litters from the two woodlands. In addition, pure cultures of four saprotrophic fungi were grown individually on irradiated hazel litter and exposed to c. 0.030μl l−1 of gaseous SO2, for 28 d in the laboratory. The gas inhibited the respiration of Phoma exigua Desm. and Phoma macrostoma Mont, but not the respiration of Cladosporium cladosporioides (Fres.) de Vries or Coniothyrium quercinum Sacc. var. glandicola Grove. These results in part substantiated findings of previous experiments examining the effects of SO2 on the structures of saprotrophic fungal communities. The effects of SO2 on fungal decomposition of angiosperm tree leaf litter as possible causes of forest decline are discussed.

Since 1987, several cytochalasins were isolated from Phoma exigua var. heteromorpha, the causal agent of a severe foliar blight disease of oleander (Nerium oleander L.), and chemically and biologically characterized. Beside their phytotoxic activity, they were in deep investigated for toxic cytological effects on mammalian cells. During the purification process of a large-scale production of cytochalasins A and B, necessary to continue the study on their anticancer activity, a metabolite having a different carbon skeleton compared to that of cytochalasans, was isolated. It was identified as terpestacin, a well-known toxic fungal stestertepenoid, isolated for the first time from P. exigua var. heteromorpha, by spectroscopic investigation (essentially 1D and 2D 1H and 13C-NMR and ESI MS) and optical methods also in comparison with the data available in literature. Terpestacin and some its derivatives (including a natural one, fusaproliferin) were prepared and tested for their biological activity. Terpestacin and fusaproliferin had some inhibitory effects on seed germination of Phelipanche ramosa, whereas none of the compounds caused phytotoxic effects on weed leaves.

Experiments were conducted under laboratory condition to examine the efficacy of Chitosan and Yeast Elicitor to suppress the growth of seed-borne fungi of cucurbitaceous vegetables. Seeds of bottle gourd, sweet gourd, snake gourd, wax gourd and cucumber were collected from seed traders of Mymensingh districts and different seed borne fungi were isolated, purified and identified. Fourteen fungal species belonging to twelve genera consisting of Aspergillus flavus, Aspergillus niger, Botrytis cinerea, Fusarium moniliforme, Fusarium oxysporum, Phoma exigua, Rhizopus stolonifer, Macrophomina phaseolina, Penicillium spp., Curvularia lunata, Chaetomium spp., Colletotrichum spp., Cercospora spp. and Alternaria alternata were isolated and identified. Four concentrations of Chitosan and Yeast Elicitors solutions (200, 500, 1000 & 2000 ppm) including one positive control Vitavax-200 WP (0.35%) were evaluated for controlling seed-borne fungi. Among the seed treating agents Chitosan (2000 ppm) and Yeast Elicitor (2000 ppm) showed better performance in suppressing the seed-borne fungi. Chitosan (2000 ppm) showed superior performance than Yeast Elicitor (2000 ppm). Results from the present study revealed that application of elicitors as seed treatment is a potential alternative of chemical fungicide for selective vegetables.J. Bangladesh Agril. Univ. 16(2): 187-192, August 2018

Aqueous formulation of rhizopheric beneficial bacteria viz . Bacillus subtilis, an exotic strain collected from Russia was assayed for its performance to suppress the growth of various seed-borne fungi of vegetable. The performance of the bio-agent was appraised based on growth suppression by dual culture method and reduction of seed-borne fungi in the bio-agent treated seeds. Ten seed samples comprise of summer and winter vegetables were examined collected from different local farmers. A total of fourteen fungal species belongs to twelve genera viz . Fusarium moniliforme , Botrytis cinerea , Aspergillus flavus , F . oxysporum , Botryodiplodia theobromae , Macrophomina phaseolina , A.niger , Cercospora sp., Phoma exigua , Rhizopus sp., Colletotrichum sp., Phytophthora sp., Penicillium sp., and Curvularia sp. were recorded from different untreated seeds. Vegetables seeds were treated in a concentration (10-3) of aqueous formulation of B. subtilis for two hours followed by air drying for 30 minutes. In general, the incidences of all fungal species of all kinds of vegetables seeds were reduced. But, selectively the best performances were observed in tomato, brinjal, cucumber, wax gourd and okra where most of the fungal species were completely suppressed by seed treatment with Bacillus subtilis . The growth of seed-borne fungi was inhibited highest in wax gourd (100%). The growth inhibition was also at satisfactory level in cucumber (95%), tomato (95%), brinjal (92%) and okra (86%) seeds. The findings of this research indicate the possibility of utilizing B. subtilis as seed treating agents instead of chemical fungicides to control seed-borne diseases of vegetables. J. Bangladesh Agril. Univ. 14(2): 177-184, December 2016

La Sericultura, es el conjunto de actividades culturales y económicas que se desarrollan en torno a la cría y explotación del gusano de seda, donde la morera es su único alimento; el follaje puede ser afectado por la presencia de patógenos que inciden en la calidad de la seda. Dentro del proyecto ‘Desarrollo tecnológico para la obtención de productos orgánicos e innovadores de seda natural’, se implementó un cultivo de morera, donde se detectó una sintomatología consistente en el necrosamiento de la base y parte media del tallo; que afecta plantas de cualquier edad y disminuye la calidad de las hojas. La enfermedad es favorecida por la época de lluvias y alta humedad relativa. El objetivo del trabajo fue identificar el agente causal de esta patología mediante la aplicación de los postulados de Koch. Fragmentos de tallos fueron aislados en cuatro medios de cultivo e incubados a dos temperaturas; posteriormente se caracterizó morfológica, patogénica y molecularmente los hongos aislados. El análisis de resultados se realizó utilizando un diseño factorial y se analizó mediante comparación de medias, evaluando la interacción de las variables. Para la identificación de los organismos, se utilizó la prueba molecular mediante la secuencia de región ITS, la cual precisó la presencia de hongos del género Phoma exigua y Myrotecium. Los resultados mostraron diferencias en el crecimiento entre hongos, medios, temperaturas e interacción de estos. En los sistemas de inoculación se observó que en ramas menores de 30 cm inoculadas con Myrothecium en la parte media, la enfermedad avanzó con rapidez. En ramas mayores y menores de 30 cm inoculadas con Phoma, el método que favoreció la infección fue el de herida en comparación con el de punción; se encontró que el micelio de los hongos utilizado como inóculo, ocasionó mayor daño que la suspensión de esporas.

Numerous reports about a disease of unknown etiology on cotton, Gossypium hirsutum L., in northeastern North Carolina and southeastern Virginia were received on 18 June 1999 following several days of cool weather with persistent mist and fog during the week of 14–19 June. Several fields were visited by consultants and county extension staff the following week. In some instances, the cotton stem was girdled, causing the upper portion of the plant to wilt and die. Cotton plants exhibiting various symptoms, including death, wilting, streaking of the vascular system, black sunken lesions on stems, and terminal necrosis were collected for examination and isolation. Pycnidia and spores of the fungus Phoma exigua were abundant in stem and terminal tissues. The fungus was isolated from infected stem tissue and cultured on PDA. A suspension containing 2.5 × 108 spores of P. exigua was sprayed on cotton leaves or injected into the stems to confirm pathogenicity. Controls were sprayed or injected with distilled water. Plants were placed in 100% humidity for 72 h and maintained in the greenhouse thereafter. The experiment was replicated five times and repeated once. Typically, streaking of the vascular system extended 1 to 5 cm from the point of stem inoculation. Inoculated cotton leaves had lesions resembling those attributed to Ascochyta gossypii. Reisolation of the fungus P. exigua from inoculated tissue on potato-dextrose agar (PDA) was successful in all treatments. Crossan (2) considered many isolates of Ascochyta taken from various hosts in North Carolina, including A. gossypii, to be synonymous with Ascochyta phaseolorum. A. phaselorum was subsequently synonomyzed with P. exigua (1). Ascochyta blight (also called ashen spot, or wet weather blight [4]) is usually a minor leaf spot caused by P. exigua (syn. Ascochyta gossypi) and is common in North Carolina. Stem canker caused by P. exigua has not been reported previously in North Carolina (3) or Virginia. The sunken canker at a node is the best diagnostic symptom for cotton stem canker. Dark streaks in vascular tissue extend below and above the canker but do not usually extend to the root system, as with wilt diseases. The disease was widespread and found in most fields north of I-40 in North Carolina into Virginia and east of I-95. Crop consultants and county extension staff estimated disease incidence in individual fields from less than 1 to over 90% in North Carolina and 6 to 25% in Virginia. Disease incidence did not appear to be affected by cotton cultivar, tillage, or crop rotation. This pathogen was also responsible for brittle cotton stems late in the season, resulting in boll loss. Proper identification of the causal organism is essential in formulating management strategies, since P. exigua has an extensive host range and rotation is unlikely to aid in management of this disease in the future. References: (1) G. H. Boerema. Ascochyta phaseolorum synonymous with Phoma exigua. Neth. J. Plant Pathol. 78:113–115, 1972. (2) D. F. Crossan. The relationships of seven species of Ascochyta occurring in North Carolina. Phytopathology 48:248–255, 1958. (3) L. F. Grand, ed. North Carolina Plant Disease Index. Tech. Bul. 240, 1985. (4) G. M. Watkins. Leaf spots. Pages 28–30 in: Compendium of Cotton Diseases, 1st ed. American Phytopathological Society, St. Paul, MN, 1981.

Phoma exigua Desm. (teleomorph Didymella exigua (Niessl) Sacc.) was isolated from wilted Centaurea solstitialis L. (yellow starthistle) plants displaying necrosis of the crown that were found near Krasnodar, Russia. The fungus was identified using morphological and cultural characteristics (1,2) and confirmed by sequencing the complete internal transcribed spacer region of the nuclear rDNA (GenBank Accession No. AY089978). P. exigua is a relatively common soilborne fungus that is weakly pathogenic on a diverse range of primarily dicotyledonous plants throughout the world (1). To our knowledge, it has never been reported previously on members of the genus Centaurea. Yellow starthistle is native to eastern Europe and the Mediterranean Region, and is now a noxious weed in North America for which P. exigua is being investigated as a potential biological control agent. Repeated pathogenicity studies (N = 30) resulted in a mortality of 80 and 93% within 7 days when 1-week-old seedlings were transplanted in soil infested with P. exigua-colonized wheat seed at rates of 6.7 and 10% (vol/vol), respectively. Symptoms of the seedlings included necrosis of the stem and wilting of the seedling. Pycnidia were observed in the roots of dead seedlings. The isolate of P. exigua has been deposited as a dried specimen at the U.S. National Fungus Collections, Beltsville, MD (BPI 841766) and as a living culture at the CBS collection in Utrecht, Netherlands (CBS 110211). References: (1) G. Morgan-Jones and K. B. Burch. Mycotaxon 32:477, 1988. (2) H. A. Van Der Aa et al. Persoonia 17:435, 2000.

Acroptilon repens (L.) DC. (Russian knapweed, synonym Centaurea repens L., family Asteraceae) is becoming a noxious weed in wheat fields in Turkey. Because it is also an invasive weed in the northwestern United States, A. repens is a target of biological control efforts. In the summer of 2002, approximately 20 dying A. repens plants were found on a roadside near Cankiri, Turkey (40°21′41″N, 33°31′8″E, elevation 699 m). No healthy plants were found in the immediate area. Dying plants had irregular, charcoal-colored, necrotic lesions at the leaf tips and margins, and frequently, whole leaves and plants were necrotic. Symptomatic leaves were air-dried and sent to the Foreign Disease-Weed Science Research Unit, USDA/ARS, Fort Detrick, MD. There, diseased leaves were surface-disinfested and placed on moist, filter paper in petri dishes. Pycnidia producing one-celled hyaline conidia were observed after 4 to 5 days. Internal transcribed spacer regions 1 and 2, including the 5.8S ribosomal DNA, were sequenced for isolate 02-059 (GenBank Accession No. AY367351). This sequence was identical to sequences in GenBank from six well-characterized strains of Phoma exigua Desmaz (1). Morphology was also consistent with P. exigua (2) with the exception that material grown on alfalfa twigs produced pycnidia with 1 to 4 ostioles with necks as much as 80 μm long. Typically, pycnidia of P. exigua produced on agar have 1 to 2 ostioles that lack necks. Conidial dimensions on alfalfa were 4.1 to 7.6 × 1.7 to 3.2 μm (average 5.5 × 2.4 μm). Images of the fungus are located at http://nt.ars-grin.gov under the section ‘Fungi Online’. Stems and leaves of 20 3-week-old plants were spray inoculated with an aqueous suspension (1 × 107 conidia per ml) of conidia harvested from 25-day-old cultures grown on acidified potato dextrose agar, and placed in an environmental chamber at 25°C with constant light and continuous dew for 3 days. Plants were then moved to a greenhouse bench and watered twice daily. After 6 days, symptoms were observed on all plants. Once symptoms had progressed to the midveins of the leaves, the disease progressed rapidly on the plants, indicating the possibility of systemic infection or systemic movement of toxins. Phoma exigua was reisolated from the stems, petioles, and leaves of all inoculated plants. In a separate test, 12 plants were inoculated as described above, and 8 additional plants were sprayed with water only. After inoculation, plants were handled as described above. The first lesions developed after 3 days on all except the youngest leaves of inoculated plants. After 10 days, three inoculated plants were dead, and all other inoculated plants had large necrotic lesions. No symptoms developed on control plants. This isolate of Phoma exigua is a destructive pathogen on A. repens, and severe disease can be produced by inoculation of foliage with an aqueous suspension of conidia. These characteristics make this isolate of P. exigua a potential candidate for biological control of this weed in Turkey and the United States. To our knowledge, this is the first report of P. exigua on A. repens in Turkey. A voucher specimen has been deposited with the U.S. National Fungus Collections (BPI 843350). References: (1) E. C. A. Abeln et al. Mycol. Res. 106:419, 2002. (2) H. A. Van der Aa et al. Persoonia 17:435, 2000.

There is a demand for environmentally friendly processes to synthesize nanoparticles. Here, we synthesized silver nanoparticles using encapsulated biomass beads of Phoma exigua var. exigua. Nanoparticles were characterized by nanoparticle tracking and analysis (NTA), Fourier-transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy and zeta potential. Results of NTA show that nanoparticle size was homogenous. Concerning nanoparticle stability, zeta potential decreased with batch number. Silver nanoparticles exhibited an antibacterial activity against Escherichia coli and Staphylococcus aureus. Overall, the encapsulation of fungal biomass by calcium alginate for the batch synthesis of silver nanoparticles was easy, cost-effective, eco-friendly and suitable for the large-scale synthesis of silver nanoparticles. We have also demonstrated the reusability of the fungal biomass during biosynthesis of silver nanoparticles using the sodium alginate encapsulation method.

The results of studies on methods of inoculation of potato tubers when assessing resistance to Phoma exigua. For this is suitable both ways tuber infection, making inokulumu (agar blocks) in the hole and sinking bubbles in the suspension of mycelium fungus.

Ascochyta blights are major diseases of many legumes and an emerging disease in many areas in which common bean (Phaseolus vulgaris L.) is grown. Ascochyta blight symptoms in bean can be caused by three fungus species. We investigated the species that caused ascochyta blight symptoms in bean crops from northern Spain using species-specific molecular markers and analysis of their nucleotide sequences. Results suggested that the two local isolates analyzed may correspond to the specie Phoma exigua var. diversispora. The variation in the reaction of common bean germplasm against a local isolate was also investigated in controlled conditions and was scored using a 1–9 severity scale. A total of 200 accessions from a core collection, 89 breeding lines and 11 accessions of Phaseolus coccineus L. were screened to identify potential sources of resistance. Most Phaseolus coccineus accessions showed higher levels of resistance (score 5). However, five breeding lines and 17 accessions exhibited moderate resistance after five resistance tests, with variation in the response of seedlings within accessions. Thus, five lines were obtained by self-pollination from each of the 17 selected accessions. Evaluation of these lines revealed significant variation within lines derived from two accessions and allowed verification of the high level of resistance in lines derived from three accessions. Finally, the lines with higher levels of resistance identified in previous evaluations were tested in three additional tests. The lines UI465, BGE04435–22 and BGE04453–4 revealed resistance levels not significantly different from the best Phaseolus coccineus accession included in this study (score < 3.5). The identified resistance sources could be used in the in the short term to increase the level of resistance to ascochyta blight in specific bean genotypes or for development of new resistant genotypes by pyramiding of genes.

Common bean (Phaseolus vulgaris L.) is cultivated extensively in Greece for dry and fresh bean production. During 2005 and 2006, a disease with typical blight symptoms was observed occasionally on dark red kidney, brown kidney, and black bean plants in most bean-producing areas of Greece. It rarely was destructive unless the crop had been weakened by some unfavorable environmental conditions. Infected leaves had brown-to-black lesions that developed concentric zones 10 to 30 mm in diameter and also contained small, black pycnidia. Concentric dark gray-to-black lesions also appeared on branches, stems, nodes, and pods. Infected seeds turned brown to black. Plants sometimes showed defoliation and pod drop. The fungus was consistently isolated on potato dextrose agar from diseased leaves and pods and identified as Phoma exigua var. exigua Sutton and Waterstone on the basis of morphological characteristics of conidia and pycnidia (1,2). Spores were massed in pycnidia from which they were forced in long, pink tendrils under moist weather conditions. Conidia were cylindrical to oval, allantoid, hyaline, pale yellow to brown, usually one-celled, and 2 to 3 × 5 to 10 μm. To satisfy Koch's postulates, a conidial suspension (1 × 106 conidia per ml) of the fungus was sprayed onto leaves and stems of bean seedlings (first-leaf stage) (cv. Zargana Hrisoupolis). Both inoculated and control seedlings (inoculated with sterile water) were covered with plastic bags for 72 h in a greenhouse at 23°C. Inoculated plants showed characteristic symptoms of Ascochyta leaf spot 12 to 15 days after inoculation. The fungus was reisolated from lesions that developed on the leaves and stems of all inoculated plants. The pathogen is present worldwide on bean. To our knowledge, this is the first report of P. exigua var. exigua on common bean in Greece. References: (1) D. F. Farr et al. Fungal Databases. Systematic Botany and Mycology Laboratory. Online publication. ARS, USDA, 2007. (2) B. C. Sutton and J. M. Waterstone. Ascochyta phaseolorum. No. 81 in: Descriptions of Pathogenic Fungi and Bacteria. CMI/AAB, Kew, Surrey, England, 1966.

In the present study, we have developed an inter-molecularly shuffled caulimoviral promoter for protein over-expression by placing the Upstream Activation Sequence (UAS) of Figwort Mosaic Virus (FMV; -249 to -54) at the 5'-end of the Cassava Vein Mosaic Virus (CsVMV) promoter fragment 8 (CsVMV8; -215 to +166) to design a hybrid promoter; FUASCsV8CP. The FUASCsV8CP promoter exhibited approximately 2.1 and 2.0 times higher GUS-activities than that obtained from the CaMV35S promoter, in tobacco (Xanthi Brad) protoplasts and in Agroinfiltration assays respectively. Hereto, when FUASCsV8CP was assayed using transgenic tobacco plants (T2- generation), it showed 2.0 times stronger activity than CaMV35S promoter and almost equivalent activity to that of CaMV35S2 promoter. The promoter displayed Salicylic acid (SA) inducibility and hence can also be used for ensuring effective gene expression in plants under constitutive as well as specific inducible conditions. Furthermore, FUASCsV8CP was used to drive the expression of victoviral Vin gene (encoding Victoriocin) transiently in tobacco. The recombinant Victoriocin could be successfully detected by western blotting three days post infiltration. Also, the in vitro Agar-based killing zone assays employing plant-derived Victoriocin-His (obtained from transient expression of Vin) revealed enhanced antifungal activity of Victoriocin against hemi-biotrophic pathogen Phoma exigua Desm. var. exigua.

Statin based compounds are widely accepted as cholesterol lowering agent. These are classified as natural, synthetic or semi synthetic derivatives of natural statins. Lovastatin is one the natural statin that acts as a competitive inhibitor of 3-hydroxy 3-methylglutaryl Coenzyme-A reductase (HMG Co-A reductase), the rate limiting enzyme of the cholesterol biosynthesis. Various fugal isolates are capable of producing lovastatin as secondary metabolite by polyketide synthesis pathway. In the present study, seven wild fungi were screened for lovastatin production by bioassay method against C. albicans and N. crassa. The results showed that, Aspergillus terreus NCIM 657 produced the maximum lovastatin (0.989 mg/ml) in the screening work through submerged fermentation. Other fungal isolates recorded lower yield of lovastatin. Further study with spectrum analysis at 238 nm and thin layer chromatography confirmed lovastatin synthesis by two more fungi i.e. Aspergillus parasiticus NCIM 898 and Phoma exigua NCIM 1237.

Panicle hydrangea (Hydrangea paniculata) is a perennial ornamental plant belonging to the Saxifragaceae commonly used in gardens, characterized by massive upright flowers from midsummer to autumn. Starting from the end of August 2017, a previously unknown leaf spot was observed on 2- to 3-year-old plants of H. paniculata grown in borders in a garden located in Valle Cervo near Biella, northern Italy (45°36′00″N, 8°03′00″E). Ten out of 20 plants grown in this garden were affected, with 30 to 40% of leaves showing symptoms, consisting initially of circular necrotic spots, with diameter ranging between 20 and 80 mm, well defined by a brown margin. Severely infected leaves became chlorotic and abscised. The disease started from basal leaves on plants grown in shadow, at high relative humidity. In several isolations carried out from infected tissues on potato dextrose agar amended with 25 mg/liter of streptomycin sulfate a fungus was consistently isolated. After 15 days of incubation, black pycnidia, 127 to 255 μm diameter, developed, releasing hyaline, elliptical, nonseptate conidia, measuring 4.3 to 10.3 μm (average 6.9 μm) × 1.9 to 4.1 μm (average 2.7 μm). On the basis of its morphological characteristics, the fungus was identified as Phoma sp. (Boerema et al. 1976). The internal transcribed spacer (ITS) region of rDNA was amplified using the primers ITS1/ITS4 and sequenced. BLAST analysis of the 517 bp obtained showed 100% homology with Boeremia exigua (formerly Phoma exigua) (GenBank accession nos. MF039478, MF599109, and MF599108). The nucleotide sequence has been assigned the GenBank accession number MG766873. Because ITS analysis was not able to identify the varietas of this species, additional genes (elongation factor 1 alpha gene [EF1α] and β-tubulin [BTUB]) were amplified with primers EF1-728F/EF2 and Bt2a/Bt2b, respectively, and sequenced. BLAST analysis of the EF1α 449-bp sequence (GenBank accession no. MG970366) and the BTUB 372-bp sequence (GenBank accession no. MG970365) showed 100 and 99% similarity with the sequences of B. exigua var. exigua (GenBank accession nos. KY550228 and KR010463, respectively). Pathogenicity tests were performed by spraying leaves of healthy 24-month-old H. paniculata plants grown in pots at temperatures between 16 and 22°C with a spore and mycelial suspension (10⁶ CFU/ml). After artificial inoculation, leaves were covered with transparent plastic bags for 5 days. Plants sprayed only with sterile water served as a control. Three plants were used for each treatment. Lesions similar to those seen in naturally infected leaves developed on leaves 7 to 10 days after inoculation in all three inoculated plants, whereas control plants remained healthy. The same fungus was consistently reisolated from the lesions. The pathogenicity test was carried out twice. To our knowledge, this is the first report of B. exigua var. exigua on H. paniculata in Italy. The pathogen has been previously reported on H. macrophylla in Italy and the United States (Farr and Rossman 2017; Garibaldi et al. 2006). The disease is at present limited to a few gardens in the mountain region where it was observed.

Ascochyta blight, caused by Phoma exigua var. diversispora (Bubak) Boerema, is a serious constraint in the cultivation of the common bean (Phaseolus vulgaris L.) in Rwanda, particularly in the cool and wet highland production areas. In order to identify resistant genotypes, a germplasm evaluation study was conducted to quantify the impact of the disease on phenotypic and agronomic traits under natural conditions. Field screening trials of 39 bush (Types I, II and III) and 36 climbing (Type IV) genotypes from different accessions within and outside the country were conducted at three sites, namely, Rwerere, Nyamagabe and Musanze Research Stations, for two seasons. The relative area under the disease progress curve (RAUDPC) based on evaluations of the disease severity (percentage leaf area infected), was used to evaluate the genotypes. Thirteen genotypes were identified with some level of ascochyta resistance. The study revealed Rwandan genotypes G 2333 and SMC 18 as new sources of resistance to Ascochyta blight. Additional results showed a negative relationship (r = −0.42 and −0.51 for Seasons A and B, respectively) between ascochyta infection and yield. Further relationships were identified between the plant flower colour and seed size to ascochyta resistance. Some of the identified resistant genotypes can be used to introgress ascochyta resistance into susceptible Rwandan market classes of common bean genotypes.

The taxonomic position and nomenclature of 22 isolates obtained from leaves, stems, roots and seeds of soybean cultivated in different regions of Poland were studies. It was proved that all the isolates represented Phoma exigua Desm. species. Isolates of Ascochyta sojaecola Abramoff from Poland are the some species as Phoma exigua.

The seeds of Bellis perennis and Celosia cristata were investigated. Agar medium with nutrients was used to isolate the fungi. Alternaria alternata dominated among isolated fungi. The investigation showed that Phoma exigua was more pathogenic to Bellis perennis.

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.

In 1998-2001, the healthiness of thyme cultivated in the region of Lublin was examined. Surveys were made on the one-year-old plantations of thyme at a stage of 6-week-old seedlings and just before the first harvest of the crop, as well as on the two-year-old plantations in spring and before the last harvest. The percentage of the plants showing fungal disease symptoms and the index of infection with fungi were determined. The fungi were isolated from superficially disinfected plant fragments namely from roots, bases of stem and leaves, separately, using mineral culture medium. PDA and SNA media were used to culture Fusarium spp., malt-agar and Czapek-Dox ones to culture Penicillium spp. and malt-agar, oat-agar and cherry-agar ones to culture Phoma spp. The percentage of plant infected with the fungi ranged within 12.18 and 23.05, in case of the one-year-old plantations, and within 29.91 and 43.65 in the two-year-old ones, whereas values of the index of infection ranged within 11.56 and 24.69 and within 20.75 and 43,28, respectively. Necroses were observed on roots and base of stems on one-year-old and two-year-old plantations, but in the last period of vegetation of thyme close to harvest. very often stems and leaves showed symptoms of a complete necrosis. It was found that base of stems and roots of thyme in the first and the second year of cultivation were colonized by a complex of pathogenic fungi:Fusarium spp., Rhizoctonia solani, Thielaviopsis basicola were obtained from the major part of diseased plants. Among the Fusarium species colonizing bases of stems F.culmorum, F.avenaceum, F.equiseti and F.oxysporum dominated, but from roots of thyme most often F.oxysporum, F.equiseti and F.culmorum were isolated. From stems, and particularly from leaves of thyme showing dark spots, commonly Alternaria alternata was obtained. On the other hand, shoots and leaves, but rarely roots of thyme, were colonized by various species of Phoma, particularly by Phoma exigua var. exigua. Colletotrichum gleosporioides occurred rarely on thyme in the area surveyed.

The aim of the study was to evaluate antifungal and antibacterial properties of surfactin isolated from Bacillus subtilis growing on molasses. Molasses replaced the traditional microbiological media to culture the B. subtilis. 10 phytopathogens and 30 E. coli strains were used in the study. The results demonstrated the ability of surfactin produced byBacillus sp. growing on molasses to inhibit mycelial growth of the 4 fungi from 10 tested and all E. coli strains measured by agar plate inhibition assays. Fungi inhibited to the greatest degree as measured by the inhibition zones were Botrytis cinerea A 258 (~50% of inhibition), Sclerotinia sclerotiorum K 2291 (~50% of inhibition), Colletotrichum gloeosporioides A 259 (~40% of inhibition), Phoma complanata A 233 (~38% of inhibition),Phoma exigua var. exigua A 175 (~20% of inhibition). Among the E. coli, high inhibition growth was noted in 76% of the isolates. Application of natural products such as biosurfactant may be a new approach to biological control therefore reducing the need for synthetic chemical compounds. Key words: Phytopathogens, Escherichia coli, Bacillus subtilis, surfactin, biocontrol, phytopathogens, biosurfactant.

S-carvone, L-menthone, peppermint and spearmint oils were tested in vitro against Fusarium coeruleum, F. sambucinum, F. avenaceum, F. oxysporum, Alternaria solani, Rhizoctonia solani, Helminthosporium solani, Phytophthora infestans (A1 and A2 mating types), Phytophthora erythroseptica, Phoma exigua and Pythium ultimum which are causal agents of major potato storage diseases. The majority of these pathogens were completely inhibited due to pure oils, although F. sambucinum, F. avenaceum, A. solani and P. exigua were not completely inhibited by one or more pure oils. Peppermint oil was the least effective among tested oils. However, R. solani, H. solani, P. erythroseptica, and P. infestans (A1 and A2 mating types) were completely inhibited for a period of 1-18 weeks by single treatments of all four pure oils. Effects of mixtures of aluminum starch octenylsuccinate (ASOS) and L-menthol or peppermint oil on F. sambucinum and R. solani were also tested in vitro for a period of over 5 weeks. Percent inhibition ...

1.Feeding by insect herbivores can affect plant growth and the concentration of defense compounds in plant tissues. Since plants provide resources for soil organisms, herbivory can also influence the composition of the soil community via its effects on the plant. Soil organisms, in turn, are important for plant growth. We tested whether insect herbivores, via their effects on the soil microbial community, can influence plant-soil feedbacks. 2.We first examined the effects of above-ground (AG) and below-ground (B) insect herbivory on the composition of pyrrolizidine alkaloids (PAs) in roots and on soil fungi in roots and rhizosphere soil of ragwort (Jacobaea vulgaris). The composition of fungal communities in roots and rhizosphere soil was affected by both AG and BG herbivory, but fungal composition also differed considerably between roots and rhizosphere soil. The composition of PAs in roots was affected only by BG herbivory. 3.Thirteen different fungal species were detected in roots and rhizosphere soil. The presence of the potentially pathogenic fungus Fusarium oxysporum decreased and that of Phoma exigua increased in presence of BG herbivory, but only in soil samples. 4.We then grew new plants in the soils conditioned by plants exposed to the herbivore treatments and in unconditioned soil. A subset of the new plants was exposed to foliar insect herbivory. Plant-soil feedback was strongly negative, but the feedback effect was least negative in soil conditioned by plants that had been exposed to BG herbivory. There was a negative direct effect of foliar herbivory on plant biomass during the feedback phase, but this effect was far less strong when the soil was conditioned by plants exposed to AG herbivory. AG herbivory during the conditioning phase also caused a soil feedback effect on the PA concentration in the foliage of ragwort. 5.Synthesis. Our results illustrate how insect herbivory can affect interactions between plants and soil organisms, and via these effects how herbivory can alter the performance of late-growing plants. Plant-soil feedback is emerging as an important theme in ecology and these results highlight that plant-soil feedback should be considered from a multitrophic AG and BG perspective

During the period 1977-1981 33 isolates of Phoma exigua were recovered from diseased leaves, stems, root crowns and seeds of soybean cultivated in different localities of Poland. None of the obtained isolates caused disease symptoms on soybean and other plant species when they were inoculated by spraying with conidial suspension. Infection developed only on wounded plants after inoculation. Phoma exigua occurring on soybean in Poland is not a specialized pathogen of this plant, but a plurivorous weak or waund parasite which attacks all kinds of plants and so is P. exigua var. exigua. Among seven of the applied inoculation methods the best one seems to be the laboratory one, in Petri plates, with culture discs exposed on the seedling hypocotyl. Other methods varied in precision and were more time-consuming.

The impact of fungal endophytes and the modulating role of arbuscular mycorrhizal fungi (AMF) on the vitality of Verbascum lychnitis, grown in the laboratory in a substratum from a post-mining waste dump was investigated. We report that inoculation with a single endophyte negatively affected the survival rate and biomass production of most of the plant-endophyte consortia examined. The introduction of arbuscular mycorrhiza fungi into this setup (dual inoculation) had a beneficial effect on both biomass yield and survivability. V. lychnitis co-inoculated with AMF and Cochliobolus sativus, Diaporthe sp., and Phoma exigua var. exigua yielded the highest biomass, exceeding the growth rate of both non-inoculated and AMF plants. AMF significantly improved the photosynthesis rates of the plant-endophyte consortia, which were negatively affected by inoculation with single endophytes. The abundance of PsbC, a photosystem II core protein previously shown to be upregulated in plants colonized by Epichloe typhina, exhibited a significant increase when the negative effect of the fungal endophyte was attenuated by AMF. Electronic supplementary material The online version of this article (doi:10.1007/s00572-017-0768-x) contains supplementary material, which is available to authorized users.

The objective of the paper was to determine the effectiveness of post-culture liquids of Bacillus sp. Bsch 19 and Pseudomonas sp. Psch 16 in the protection of soybean from soil-borne fungi. The use of post-culture liquids of those bacteria in seed dressing positively affected the number, healthiness and yielding of soybean plants. The plants were mainly infected by Fusarium spp., Phoma exigua var. exigua, Rhizoctonia solani and Sclerotinia sclerotiorum. Those fungi were isolated much more rarely from the plants in combinations with the use of post-culture liquids of antagonistic bacteria as compared with the plants from the control combination, i.e. without seed dressing. A reverse relation was found for the occurrence of saprophytic fungi from the genera of Gliocladium, Penicillium and Trichoderma