Journal articles: 'Phoma tropica'

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Rai, Mahendra, Aniket Gade, Beata Zimowska, Avinash P. Ingle, and Pramod Ingle. "A HARNESSING THE POTENTIAL OF NOVEL BIOACTIVE COMPOUNDS PRODUCED BY ENDOPHYTIC Phoma spp.: BIOMEDICAL AND AGRICULTURAL APPLICATIONS." Acta Scientiarum Polonorum Hortorum Cultus 19, no. 6 (December 31, 2020): 31–45. http://dx.doi.org/10.24326/asphc.2020.6.3.

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Endophytes are those inhabiting in plants without causing any apparent loss to the host plant. Phoma is a ubiquitously found genus of fungi in soil, water and air. Endophytic Phoma spp. are distributed with high specific diversity, those occur in plants and are mainly responsible for the production of a vast range of secondary metabolites. These secondary metabolites or the bioactive compounds have demonstrated a wide range of activity ranging from antibacterial, antifungal, antiviral, algicidal, cytotoxic, antitubercular and plant growth promoting, etc. Bioactive compounds are produced by Phoma herbarum, P. sorghina, P. exigua, P. macrostoma, P. medicaginis, P. betae, P. tropica and others. The present review emphasizes on different species of endophytic Phoma as novel source of bioactive compounds, and their applications in medicine and agriculture are documented.

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V A, Patil, Mehta B P, Sabalpara A N, and Deshmukh A J. "Evaluation of Botanicals against Phoma tropica Causing Leaf Spot Disease in Lablab purpureus." Madras Agricultural Journal 99, JUNE (2012): 359–60. http://dx.doi.org/10.29321/maj.10.100086.

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The aqueous phytoextracts of commonly available seventeen plant species were evaluated in vitro by poisoned food technique against their inhibitory effect on the mycelial growth and micro-sclerotial formation in Phoma tropica. The extract of Gando baval (Prosopis juliflora L.) proved excellent in inhibiting mycelial growth and micro-sclerotial production. Extracts of nilgiri, turmeric, marigold. Pink barmasi, tulsi, ardusi, Jetropha, Bougainvillea, karanj, Lantana, onion, ginger, garlic, Dhatura and neem were found slightly inhibitory.

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Garibaldi, A., G. Gilardi, G. Ortu, and M. L. Gullino. "First Report of Leaf Spot of Lettuce (Lactuca sativa L.) Caused by Phoma tropica in Italy." Plant Disease 96, no. 9 (September 2012): 1380. http://dx.doi.org/10.1094/pdis-04-12-0394-pdn.

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Lettuce (Lactuca sativa L.) is widely grown in Italy, with the production for the preparation of ready-to-eat salads becoming increasingly important. During the spring of 2011, a previously unknown leaf spot was observed on L. sativa plants, cv Rubia, grown in several plastic tunnels in Lumbardy (northern Italy), 20 to 25 days after sowing. Thirty to forty per cent of leaves of the plants growing in the part of the tunnel with the highest relative humidity were affected. Leaves of infected plants showed extensive, irregular, dark brown, necrotic lesions with a chlorotic halo. Lesions initially ranged from 0.5 to 3 mm, then eventually coalesced, reaching 2 to 3 cm, showing a well-defined, dark brown border. Affected leaves senesced and withered. The crown was not affected by the disease. Diseased tissue was excised, immersed in a solution containing 1% sodium hypochlorite for 60 s, rinsed in water, then cultured on potato dextrose agar (PDA), amended with 25 mg/l of streptomycin sulphate. After 5 days, a fungus developed, producing a greenish grey mycelium with a white border when incubated under 12 h/day of fluorescent light at 21 to 23°C. In order to favor the production of conidia, the fungus was transferred on malt extract agar (MA) and maintained under 12 h/day of fluorescent light at 22°C. After 15 days, black pycnidia, 175 to 225 μm, developed, with hyaline, elliptical, unicellular conidia, measuring 3.21 to 6.7 × 1.08 to 3.2 (average 5.5 × 1.9) μm. On the basis of these morphological characteristics, the fungal causal agent of the disease could be related to the genus Phoma (2). The internal transcribed spacer (ITS) region of rDNA of the isolate PHT30 was amplified using the primers ITS1/ITS4 and sequenced. BLAST analysis (1) of the 466-bp segment showed a 99% similarity with the sequence of Phoma tropica (GenBank Accession No. JF923820.1). The nucleotide sequence has been assigned the GenBank Accession No. JQ954396. Pathogenicity tests were performed by spraying healthy 20-day-old lettuce plants, cv Rubia, with a spore suspension (1 × 105 conidia/ml) prepared from 14-day-old colonies of the strain PHT30 grown on MA cultures. Plants inoculated with water alone served as controls. Ten plants per isolate were used. Plants were covered with plastic bags for 5 days after inoculation and maintained in a growth chamber at 20°C and 80% relative humidity. The first foliar lesions, similar to those occurring on the naturally infected plants, developed on leaves 12 days after inoculation. Control plants remained healthy. The pathogen was consistently reisolated from leaf lesions. The pathogenicity test was completed twice. To our knowledge, this is the first report of the presence of P. tropica on lettuce in Italy as well as worldwide. In the United States, the presence of P. exigua was reported in 2006 (3). The economic importance of the disease at present is limited, probably also because symptoms can be confused with those caused by Botrytis cinerea. However, P. tropica could become a more significant problem because of the importance of the crop. References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997. (2) G. H. Boerema. Trans. Br. Mycol. Soc. 67:289, 1976. (3) S. Y. Koike. Plant Dis. 90:1268, 2006.

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Krishnamoorthy, R., P. Arul Jose, M. Ranjith, R. Anandham, K. Suganya, J. Prabhakaran, S. Thiyageshwari, Jijo Johnson, N. O. Gopal, and K. Kumutha. "Decolourisation and degradation of azo dyes by mixed fungal culture consisted of Dichotomomyces cejpii MRCH 1-2 and Phoma tropica MRCH 1-3." Journal of Environmental Chemical Engineering 6, no. 1 (February 2018): 588–95. http://dx.doi.org/10.1016/j.jece.2017.12.035.

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Mallmann, Guilherme, Jaqueline Rosemeire Verzignassi, Celso Dornelas Fernandes, Jaime Maia dos Santos, Marta Helena Vechiato, Carlos Antonio Inácio, Margareth Vieira Batista, and Carolina de Arruda Queiroz. "Fungos e nematoides associados a sementes de forrageiras tropicais." Summa Phytopathologica 39, no. 3 (September 2013): 201–3. http://dx.doi.org/10.1590/s0100-54052013000300010.

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Objetivou-se avaliar a incidência de fungos e nematoides em sementes de Brachiaria sp. e Panicum maximum produzidas nos estados de Mato Grosso do Sul (MS), Mato Grosso (MT), Goiás (GO), Minas Gerais (MG) e São Paulo (SP). Os principais fungos encontrados nas sementes foram Bipolaris sp., Curvularia sp. e Phoma sp.. As menores incidências destes fungos foram encontradas nas sementes das cultivares BRS Piatã e Xaraés de Brachiaria brizantha e Brachiaria decumbens cv. Basilisk, oriundas dos estados de GO, MG e MS, respectivamente. As cultivares Marandu e BRS Piatã, provenientes das várias regiões, apresentaram elevada ocorrência de Aphelenchoides sp. e Ditylenchus sp.. Sementes da cultivar Humidicola, de Brachiaria humidicola, produzidas em MS e SP, não apresentaram associação com nematoides. As sementes de Panicum maximum cv. Massai e cv. Mombaça apresentaram maiores incidências de Bipolaris sp., Cladosporium sp., Curvularia sp., Fusarium sp. e Phoma sp., bem como de Aphelenchoides sp. e Ditylenchus sp., especialmente nas sementes produzidas em MT. Alguns dos patógenos encontrados são agentes causais de doenças de grande importância em forrageiras, a exemplo de Bipolaris sp., causando a mancha foliar do Panicum, de alta severidade em Tanzânia, proporcionando sérios comprometimentos da sustentabilidade das pastagens.

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Herath, Kithsiri, Guy Harris, Hiranthi Jayasuriya, Deborah Zink, Scott Smith, Francisca Vicente, Gerald Bills, et al. "Isolation, structure and biological activity of phomafungin, a cyclic lipodepsipeptide from a widespread tropical Phoma sp." Bioorganic & Medicinal Chemistry 17, no. 3 (February 2009): 1361–69. http://dx.doi.org/10.1016/j.bmc.2008.12.009.

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Santos, Gil Rodrigues dos, Paulo Henrique Tschoeke, Luciana de Godoi Silva, Marcela Cristina Agustini Carneiro da Silveira, Higor Barbosa Reis, Deyvid Rocha Brito, and Dalmarcia de Souza Carlos. "Sanitary analysis, transmission and pathogenicity of fungi associated with forage plant seeds in tropical regions of Brazil." Journal of Seed Science 36, no. 1 (2014): 54–62. http://dx.doi.org/10.1590/s2317-15372014000100007.

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Brazil is a major producer and exporter of beef in the world, 90% of the production is made in pasture and 85% of cultivated pastures in the country are Brachiaria sp. With a growing livestock industry in the recent years, several forage plant diseases became significant importance for causing losses in pasture productivity and quality. This study aims at quantifying the species of fungi associated with seeds and their frequency in forage plants from tropical regions of Brazil. Assays were performed considering: incidence, pathogenicity and seed-seedling transmission of fungi associated with seeds. Therefore, 28 lots of forage species seeds produced in the harvest of 2010-2011 were used. Fourteen genera of fungi associated with seeds were found, among which Bipolaris sp., Phoma sp., and Curvularia sp. had pathogenic potential. It was possible to note that Bipolaris sp., is prejudicial to forage seedlings of Brachiaria, Panicum and Crotalaria. Bipolaris sp. and Curvularia sp. have an average of seed-seedling transmission of 100% and 90%, respectively.

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Ojha, Suprakash, Manoranjan Chakraborty, and Narayan Chandra Chatterjee. "Antagonistic potentials of Trichoderma Spp. against fruit rot of custard apple caused by Phoma ligam." Journal of Bio-Science 19 (December 19, 2012): 15–21. http://dx.doi.org/10.3329/jbs.v19i0.12995.

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Context: Custard-apple (Annona squamosa Linn.) is a popular tropical fruit and fruit-rot disease caused by Phoma lingam leads to considerable qualitative and quantitative damages to the fruit in the area under study. Objective: Studies were conducted to investigate the antagonistic potential of five Trichoderma spp. namely, T. harzianum, T. hamatum, T. lignorum, T. reesei and T. viride against in vitro growth of the pathogen followed by field experiments. Materials and Methods: Dual culture plate, closed petriplate and food poisoning technique were followed in order to ascertain the antagonistic potential of the five species of Trichoderma. Hyphal interaction between the pathogen and T. viride was studied by collecting mycelial samples from the interaction zone of dual culture plate and was processed for scanning electron microscope. Plants with infected fruits were sprayed with spore suspension of T. viride and two commercial bioformulations of T. viride viz. Trichofix and Trichoguard for three times at a dose of 0.1, 0.5 and 1.0% prepared in distilled water. Results: All the Trichoderma species more or less effectively inhibited the growth of the pathogen through mycoparasitism, production of volatile and non-volatile metabolites. Scanning electron microscopic (SEM) micrographs revealed that hyphal interaction between P. lingam and T. viride leads to lysis of the pathogenic mycelium by the antagonist. Field experiments with spore suspension of T. viride and Trichofix and Trichoguard significantly reduced fruit rot incidence of custard-apple. Conclusion: The results of the current study indicate that adoption of biocontrol based disease management programmes can be effectively utilized against similar fruit diseases. DOI: http://dx.doi.org/10.3329/jbs.v19i0.12995 J. bio-sci. 19: 15-21, 2011

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Elorriaga-Verplancken, Fernando R., Laura Morales-Luna, Gisela Heckel, and Yolanda Schramm. "Foraging ecology of harbour seals (Phoca vitulina) and Northern elephant seals (Mirounga angustirostris) from Baja California, Mexico: inferences from stable isotopes in pups." Journal of the Marine Biological Association of the United Kingdom 96, no. 4 (December 22, 2015): 903–8. http://dx.doi.org/10.1017/s0025315415002143.

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Harbour seals (Phoca vitulina) and northern elephant seals (Mirounga angustirostris) are the only phocid species found in Mexico. There is evidence that harbour seals at other latitudes exhibit non-migratory behaviour; however, there is lack of knowledge regarding this species' movements in Mexico. In contrast, elephant seal migrations to high latitudes are documented. In order to analyse this behaviour in harbour seals, hair samples (N = 19) were collected from weaned, or nearly weaned, pups on Natividad Island, Baja California (BC), during the 2013 breeding season (February). Lanugo samples (N = 20) were also collected from elephant seal pups on the San Benito Archipelago (60 km north of Natividad) during the same season, providing information on maternal foraging during the last 4–5 months before sampling. Of the two species, BC harbour seals had higher isotope values, reflecting their non-migratory behaviour. These differences may be due to the depleted base values in the higher latitude foraging areas used by northern elephant seals relative to the areas around Natividad frequented by harbour seals. A lower trophic position by elephant seals was considered but taken as an unlikely explanation for this variation. Bayesian analysis confirmed the distinction, with a low overlap value (0.4) and different isotopic spaces (Phoca: 0.5, Mirounga: 1.6). Building upon previous studies of the trophic ecology of the two phocids that inhabit the region, we provide new information by comparing the two species during the same season using the same tissue type sampled from individuals of similar age classes.

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Renner, Martin, Mayumi L. Arimitsu, and John F. Piatt. "Structure of marine predator and prey communities along environmental gradients in a glaciated fjord." Canadian Journal of Fisheries and Aquatic Sciences 69, no. 12 (December 2012): 2029–45. http://dx.doi.org/10.1139/f2012-117.

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Spatial patterns of marine predator communities are influenced to varying degrees by prey distribution and environmental gradients. We examined physical and biological attributes of an estuarine fjord with strong glacier influence to determine the factors that most influence the structure of predator and prey communities. Our results suggest that some species, such as walleye pollock (Theragra chalcogramma), black-legged kittiwake (Rissa tridactyla), and glaucous-winged gull (Larus glaucescens), were widely distributed across environmental gradients, indicating less specialization, whereas species such as capelin (Mallotus villosus), harbor seal (Phoca vitulina), and Kittlitz's murrelet (Brachyramphus brevirostris) appeared to have more specialized habitat requirements related to glacial influence. We found that upper trophic level communities were well correlated with their mid trophic level prey community, but strong physical gradients in photic depth, temperature, and nutrients played an important role in community structure as well. Mid-trophic level forage fish communities were correlated with the physical gradients more closely than upper trophic levels were, and they showed strong affinity to tidewater glaciers. Silica was closely correlated with the distribution of fish communities, the mechanisms of which deserve further study.

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Bentzen, T. W., E. H. Follmann, S. C. Amstrup, G. S. York, M. J. Wooller, D. C. G. Muir, and T. M. O’Hara. "Dietary biomagnification of organochlorine contaminants in Alaskan polar bears." Canadian Journal of Zoology 86, no. 3 (March 2008): 177–91. http://dx.doi.org/10.1139/z07-124.

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Concentrations of organochlorine contaminants in the adipose tissue of polar bears ( Ursus maritimus Phipps, 1774) vary throughout the Arctic. The range in concentrations has not been explained fully by bear age, sex, condition, location, or reproductive status. Dietary pathways expose polar bears to a variety of contaminant profiles and concentrations. Prey range from lower trophic level bowhead whales ( Balaena mysticetus L., 1758), one of the least contaminated marine mammals, to highly contaminated upper trophic level ringed seals ( Phoca hispida (Schreber, 1775)). We used δ15N and δ13C signatures to estimate the trophic status of 42 polar bears sampled along Alaska’s Beaufort Sea coast to determine the relationship between organochlorine concentration and trophic level. The δ15N values in the cellular portions of blood ranged from 18.2‰ to 20.7‰. We found strong positive relationships between concentrations of the most recalcitrant polychlorinated biphenyls (PCBs) and δ15N values in models incorporating age, lipid content, and δ13C value. Specifically these models accounted for 67% and 76% of the variation in PCB153 and oxychlordane concentration in male polar bears and 85% and 93% in females, respectively. These results are strong indicators of variation in diet and biomagnification of organochlorines among polar bears related to their sex, age, and trophic position.

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Falk-Petersen, Stig, Tore Haug, Kjell T. Nilssen, Anette Wold, and Trine M. Dahl. "Lipids and trophic linkages in harp seal (Phoca groenlandica) from the eastern Barents Sea." Polar Research 23, no. 1 (June 2004): 43–50. http://dx.doi.org/10.3402/polar.v23i1.6265.

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Falk-Petersen, Stig, Tore Haug, Kjell T. Nilssen, Anette Wold, and Trine M. Dahl. "Lipids and trophic linkages in harp seal (Phoca groenlandica) from the eastern Barents Sea." Polar Research 23, no. 1 (June 2004): 43–50. http://dx.doi.org/10.1111/j.1751-8369.2004.tb00128.x.

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Atwell, Lisa, Keith A. Hobson, and Harold E. Welch. "Biomagnification and bioaccumulation of mercury in an arctic marine food web: insights from stable nitrogen isotope analysis." Canadian Journal of Fisheries and Aquatic Sciences 55, no. 5 (May 1, 1998): 1114–21. http://dx.doi.org/10.1139/f98-001.

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Several recent studies have shown that the use of delta 15N analysis to characterize trophic relationships can be useful for tracing biocontaminants in food webs. In this study, concentration of total mercury was measured in tissues from 112 individuals representing 27 species from the arctic marine food web of Lancaster Sound, Northwest Territories. Samples ranged from particulate organic matter through polar bears (Ursus maritimus). Using delta 15N values to identify trophic position, we found that total mercury in muscle tissue biomagnified in this food web. Polar bears were a notable exception, having a lower mean mercury concentration than their main prey, ringed seals (Phoca hispida). Most vertebrates showed greater variance in mercury concentration than invertebrates, and there was a trend in seabirds toward increased variability in mercury concentration with trophic position. Within species, we found no evidence of bioaccumulation of mercury with age in the muscle tissue of clams (Mya truncata) or ringed seals. Because stable nitrogen isotopes illustrated the relationship in this biome between trophic position and mercury level on a continuous, quantitative scale, we were able to determine that log10[Hg] ( µg/g dry weight) = 0.2( delta 15N) - 3.3. The measurement of delta 15N values and mercury concentration allowed us to quantitatively assess mercury biomagnification within this extensive arctic marine food web.

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Bentzen, T. W., E. H. Follmann, S. C. Amstrup, G. S. York, M. J. Wooller, and T. M. O’Hara. "Variation in winter diet of southern Beaufort Sea polar bears inferred from stable isotope analysis." Canadian Journal of Zoology 85, no. 5 (May 2007): 596–608. http://dx.doi.org/10.1139/z07-036.

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Ringed seals ( Phoca hispida Schreber, 1775 = Pusa hispida (Schreber, 1775)) and bearded seals ( Erignathus barbatus (Erxleben, 1777)) represent the majority of the polar bear ( Ursus maritimus Phipps, 1774) annual diet. However, remains of lower trophic level bowhead whales ( Balaena mysticetus L., 1758) are available in the southern Beaufort Sea and their dietary contribution to polar bears has been unknown. We used stable isotope (13C/12C, δ13C, 15N/14N, and δ15N) analysis to determine the diet composition of polar bears sampled along Alaska’s Beaufort Sea coast in March and April 2003 and 2004. The mean δ15N values of polar bear blood cells were 19.5‰ (SD = 0.7‰) in 2003 and 19.9‰ (SD = 0.7‰) in 2004. Mixing models indicated bowhead whales composed 11%–26% (95% CI) of the diets of sampled polar bears in 2003, and 0%–14% (95% CI) in 2004. This suggests significant variability in the proportion of lower trophic level prey in polar bear diets among individuals and between years. Polar bears depend on sea ice for hunting seals, and the temporal and spatial availabilities of sea ice are projected to decline. Consumption of low trophic level foods documented here suggests bears may increasingly scavenge such foods in the future.

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Dai, Fuqiang, Hao Liu, Xia Zhang, and Qing Li. "Exploring the Emerging Trends of Spatial Epidemiology: A Scientometric Analysis Based on CiteSpace." SAGE Open 11, no. 4 (October 2021): 215824402110587. http://dx.doi.org/10.1177/21582440211058719.

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Infectious diseases are common challenges faced by people around the world, which jeopardize public health, as well as human well-being in various aspects of social and economic development. Although much progress has been made in spatial epidemiology, there is still very little scientific understanding of knowledge domain mapping with scientometric analysis. Based on a total of 4,552 literature records collected from the Web of Science Core Collection™, quantitative changes, research frontiers, research hotspots, and collaboration networks were analyzed by CiteSpace. The results show that both total publications and sum of times cited per year exhibit a rapid development trend in recent decades. The USA, England, and France are highly active in the field. The network of documents co-citation analysis is validated with almost same importance of documents, and primary research frontiers are landscape genetics, modeling and spatial analysis, and tropical diseases. The clustering of the keywords co-occurrence analysis network is heterogeneous and highly reliable, and research hotspots are related to phoma stem canker, vector preference, and aerosol chemical component. Scholars in the field of spatial epidemiology are closely connected, and they have been in a stable cooperative network, as well as institutions. Overall, scientometric analysis based on CiteSpace provides a sound tool to better understand the frontiers, hotspots, and emerging trends in the research domain of spatial epidemiology.

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Neale, Jennifer C. C., Judith A. Van de Water, James T. Harvey, Ronald S. Tjeerdema, and M. Eric Gershwin. "Proliferative Responses of Harbor Seal (Phoca vitulina) T Lymphocytes to Model Marine Pollutants." Developmental Immunology 9, no. 4 (2002): 215–21. http://dx.doi.org/10.1080/10446670310001593523.

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In recent years, population declines related to viral outbreaks in marine mammals have been associated with polluted coastal waters and high tissue concentrations of certain persistent, lipophilic contaminants. Such observations suggest a contributing role of contaminant-induced suppression of cell-mediated immunity leading to decreased host resistance. Here, we assessed the effects of the prototypic polycyclic aromatic hydrocarbon (PAH), benzo[a]pyrene (B[a]P), and two polychlorinated biphenyls (PCBs), CB-156 and CB-80, on the T-cell proliferative response to mitogen in harbor seal peripheral lymphocytes. Despite the variability associated with our samples from free-ranging harbor seals, we observed a clear suppressive effect of B[a]P (10 uM) exposure on T cell mitogenesis. Exposures to 10 uM CB-156 and CB-80, and 1.0 and 0.1 uM B[a]P, did not produce significant depression in lymphoproliferation. Exposure to the model PAH at 10 uM resulted in a 61% (range 34-97%) average reduction in lymphoproliferation. We were able to rule out a direct cytotoxic effect of B[a]P, indicating that observed effects were due to altered T cell function. Based on ourin vitroresults, we hypothesize that extensive accumulation of PAH by top-trophic-level marine mammals could alter T cell activationin vivoand impaired cell-mediated immunity against viral pathogens.

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Talamini, Viviane, Edson Ampélio Pozza, Paulo Estevão de Souza, Daniel Garcia Júnior, Hilário Antônio de Castro, Ricardo Magela de Souza, and Mário Sobral de Abreu. "Dez anos da clínica fitossanitária da UFLA - freqüência da ocorrência de patógenos, sintomas e principais hospedeiros." Ciência e Agrotecnologia 27, no. 1 (February 2003): 70–75. http://dx.doi.org/10.1590/s1413-70542003000100008.

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Com o presente trabalho objetivou-se analisar os diagnósticos realizados na Clínica Fitossanitária do Departamento de Fitopatologia da Universidade Federal de Lavras, no período de 1990 a 1999. Foram analisadas 85 espécies de hospedeiros, num total de 1429 amostras. Os fungos, com 70,5%, as bactérias, com 12,9% e as viroses, com 1,2%, foram os agentes etiológicos de doenças bióticas encontrados com maior freqüência. A deficiência nutricional e a fitotoxidez representaram 15,4%. O fungo de maior ocorrência foi o gênero Fusarium, associado a 25,5% das doenças, seguido de Colletotrichum (16%), Rhizoctonia (11%), Alternaria (5%), Cercospora (4%), espécies do grupo Helminthosporium (4%) e Phoma (3,5%). Os demais gêneros de fungos representaram 32% das amostras. Entre os agentes etiológicos bacterianos, destacou-se o gênero Erwinia, com 35% das amostras, seguida pelos gêneros Streptomyces (30%), Ralstonia (13,5%), Pseudomonas (11,5%), Xanthomonas (9,5%) e Agrobacterium (0,5%). As manchas foliares foram os sintomas de maior ocorrência, encontrados em 40% das amostras recebidas, seguidas das murchas (22%), cancros e sarnas (17%), podridões (14%) e tombamento (3%). Outros sintomas totalizaram 4% das amostras recebidas. Entre os hospedeiros, as hortaliças destacaram-se com 27% das ocorrências, os grãos, com 24%, as frutíferas tropicais, com 17%, as ornamentais, com 15%, as frutíferas temperadas, com 3%, forrageiras, com 2%, oleaginosas, com 2% e outros, com 10%.

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Joseph, Djeugap Fovo, Ngoune Djouke Patrick Francky, Ntabe Ngbanye Eric, and Gweth Likaa René Samuel. "Susceptibility of Pericopsis elata (Assamela) to heartwood decay and identification of micro and macro fungi associated with the disease in Cameroon." Annals of Plant Sciences 6, no. 11 (November 1, 2017): 1751. http://dx.doi.org/10.21746/aps.2017.6.11.6.

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Heartwood decay is one of the major pathological constraints affecting the quality and marketable volume of tropical timber. A study on its behavior was conducted on Pericopsis elata in order to contribute to its sustainable management in Cameroon. Tree susceptibility to heartwood decay was evaluated using three diameter classes, based on allometric equations between decayed and healthy trees. Wood samples and visible macromycetes were taken from living and felled trees with an auger. Isolation of microfungi was performed on potato dextrose agar medium and their identification was based on the morphological and microscopic characteristics of the mycelium and conidia with reference to identification keys of mycology. Identification of macromycetes was based on their morphological characteristics as described in reference books on macromycetes identification. Results show that diameter class ]110, 120[ presented highly significant (P<0.05) volume loss (3755.96 cm3), followed by diameter class ]100, 110[. Microfungi frequently associated with heartwood decay of P. elata were Cercospora sp (24.57%), Fusarium oxysporum (12.64%) and Penicillium sp (12.58%) in living decay trees and Aspergillus niger (25.19%), Cercospora sp (22.21%), Penicillium sp (17.69%) and Phoma sp (15.05%) in felled decay trees. Macrofungi associated with living trees were Inonotus sp and Ganoderma sp. This is the first time that these fungal species are reported on P. elata wood. This study provides baseline information for the study of heartwood decay and management of P. elata in Cameroon.

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Novtahaning, Damar, Hasnain Ali Shah, and Jae-Mo Kang. "Deep Learning Ensemble-Based Automated and High-Performing Recognition of Coffee Leaf Disease." Agriculture 12, no. 11 (November 13, 2022): 1909. http://dx.doi.org/10.3390/agriculture12111909.

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Coffee is the world’s most traded tropical crop, accounting for most export profits, and is a significant source of income for the countries in which it is produced. To meet the needs of the coffee market worldwide, farmers need to increase and monitor coffee production and quality. Coffee leaf disease is a significant factor that decreases coffee quality and production. In this research study, we aim to accurately classify and detect the diseases in four major types of coffee leaf disease (phoma, miner, rust, and Cercospora) in images using deep learning (DL)-based architectures, which are the most powerful artificial intelligence (AI) techniques. Specifically, we present an ensemble approach for DL models using our proposed layer. In our proposed approach, we employ transfer learning and numerous pre-trained CNN networks to extract deep characteristics from images of the coffee plant leaf. Several DL architectures then accumulate the extracted deep features. The best three models that perform well in classification are chosen and concatenated to build an ensemble architecture that is then given into classifiers to determine the outcome. Additionally, a data pre-processing and augmentation method is applied to enhance the quality and increase the data sample’s quantity to improve the training of the proposed method. According to the evaluation in this study, among all DL models, the proposed ensemble architecture outperformed other state-of-the-art neural networks by achieving 97.31% validation. An ablation study is also conducted to perform a comparative analysis of DL models in different scenarios.

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MacKenzie, Brian R., Jürgen Alheit, Daniel J. Conley, Poul Holm, and Carl Christian Kinze. "Ecological hypotheses for a historical reconstruction of upper trophic level biomass in the Baltic Sea and Skagerrak." Canadian Journal of Fisheries and Aquatic Sciences 59, no. 1 (January 1, 2002): 173–90. http://dx.doi.org/10.1139/f01-201.

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Fish and marine mammal populations in the Baltic Sea and Skagerrak have undergone major fluctuations over the past five centuries. We summarize how these fluctuations may have depended on various forms of predation (e.g., cannibalism, fishing, hunting) and environmental processes. The best-documented long-term fisheries in this region are the herring (Clupea harengus) fisheries near Bohuslän, western Sweden, and in the Øresund. These fisheries have been important since at least the 1200s and appear to be partly climatically driven. However, in the rest of the Baltic, information about fisheries for herring and other fish species is rare until after 1900. During the 20th century, while the Baltic underwent eutrophication, the biomass and landings of three fish species (cod (Gadus morhua), herring, and sprat (Sprattus sprattus)) all increased, whereas the biomass of marine mammals (grey seals (Halichoerus grypus), ringed seals (Phoca hispida), harbour porpoises (Phocoena phocoena)) decreased. The relative roles of exploitation, marine mammal predation, and environmental variability (e.g., eutrophication, major inflows of saline water, climate change) on the long-term dynamics of key fish species is not clear and requires increased collaboration among historians, fisheries and marine mammal ecologists, oceanographers, and climatologists.

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Fernandes, Celso Dornelas, Jaqueline Rosemeire Verzignassi, Guilherme Mallmann, and Carolina de Arruda Queiróz. "Controle químico da mela-das-sementes e do carvão em cultivares de Brachiaria brizantha." Summa Phytopathologica 43, no. 2 (June 2017): 136–44. http://dx.doi.org/10.1590/0100-5405/2102.

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RESUMO O Brasil é o maior produtor, consumidor e exportador mundial de sementes de espécies forrageiras tropicais. Contudo, a produção tem sido ameaçada pela presença de fungos e fitonematoides, os quais podem reduzir a produtividade e/ou a qualidade das sementes produzidas, além de constituírem barreiras sanitárias para vários países importadores dessas sementes. Em Brachiaria spp., as principais doenças são a mela-das-sementes e o carvão, causadas, respectivamente, pelos fungos Claviceps maximensis e Ustilago operta. Apesar da grande demanda pelo setor produtivo, poucos são os estudos relacionados a estratégias de controle das doenças. Assim, realizou-se este trabalho objetivando-se avaliar a eficiência de fungicidas no controle das referidas doenças. Implantaram-se quatro experimentos, sendo dois na Embrapa Gado de Corte, em Campo Grande-MS, e dois em Paraíso das Águas-MS. Foram utilizadas as cultivares BRS Piatã e Xaraés, ambas pertencentes à Brachiaria brizantha. Foram avaliados os efeitos de vários fungicidas (g ia/ha), os quais foram aplicados em três épocas para Campo Grande: plantas com 10% de antese, 20 e 40 dias após a primeira aplicação. Em Paraíso das Águas, os fungicidas foram aplicados uma única vez, nas plantas com 10% de antese. Na cultivar BRS Piatã, para Campo Grande, os melhores resultados obtidos para o controle da mela-das-sementes foram com os tratamentos T7 (trifloxistrobina + ciproconazole (150,0 + 64,0)) e T11 (primeira aplicação: piraclostrobina (97,5) + epoxiconazole (60,0), segunda aplicação: tebuconazole (120,0), terceira aplicação: piraclostrobina (97,5) + epoxiconazole (60,0)). Na cultivar Xaraés, a doença foi menos expressiva nos tratamentos T4 (piraclostrobina (175,0)), T6 (azoxistrobina + ciproconazole (80,0 + 32,0)), T9 (primeira aplicação: piraclostrobina (175,0); segunda e terceira aplicações: piraclostrobina + epoxiconazole (99,75 + 37,5)) e T11 (primeira aplicação: piraclostrobina (97,5) + epoxiconazole (60,0), segunda aplicação: tebuconazole (120,0), terceira aplicação: piraclostrobina + epoxiconazole (97,5 + 60,0)). Não houve ocorrência de carvão para ambas as cultivares em Campo Grande. Para BRS Piatã, no experimento de Paraíso das Águas-MS, apesar da intensidade de mela-das-sementes e de carvão não terem sido expressivas, no tratamento T4 (piraclostrobina (175,0) a produtividade de sementes puras foi 69,6% maior que a testemunha, produzindo 456,78 kg/ha, demonstrando alta relação benefício/custo com o referido tratamento. Tal resultado em T4 pode ter sido expressão de efeitos fisiológicos proporcionados pela piraclostrobina. A aplicação de fungicidas na parte aérea das plantas de BRS Xaraés de Brachiaria brizantha em Campo Grande, onde houve alta incidência dos fungos Alternaria spp., Bipolaris spp., Curvularia spp., Fusarium spp. e Phoma spp. nas sementes, revelou o efeito benéfico do tratamento, sobretudo do T7 (trifloxistrobina + ciproconazole (150,0 + 64,0)), o qual reduziu significativamente a ocorrência de Bipolaris spp., Fusarium spp. e Phoma spp. Em Paraíso das Águas, onde a incidência dos referidos patógenos foi menor, os resultados não foram conclusivos.

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Savenkoff, Claude, Martin Castonguay, Alain F. Vézina, Simon-Pierre Despatie, Denis Chabot, Lyne Morissette, and Mike O. Hammill. "Inverse modelling of trophic flows through an entire ecosystem: the northern Gulf of St. Lawrence in the mid-1980s." Canadian Journal of Fisheries and Aquatic Sciences 61, no. 11 (November 1, 2004): 2194–214. http://dx.doi.org/10.1139/f04-154.

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Mass-balance models using inverse methodology have been constructed for the northern Gulf of St. Lawrence ecosystem in the mid-1980s, before the groundfish collapse. The results highlight the effects of the major mortality sources (fishing, predation, and other sources of mortality) on the fish and invertebrate communities. Main predators of fish were large cod (Gadus morhua) followed by redfish (Sebastes spp.), capelin (Mallotus villosus), and fisheries. Large cod were the most important predator of small cod, with cannibalism accounting for at least 44% of the mortality of small cod. The main predators of large cod were harp (Phoca groenlandica) and grey (Halichoerus grypus) seals. However, predation represented only 2% of total mortality on large cod. Mortality other than predation dominated the mortality processes at 52% of the total, while the fishery represented 46%. Tests were performed to identify possible sources of this unexplained mortality. The only way to significantly reduce unexplained mortality on large cod in the model was to increase landings of large cod above those reported. This suggests that fishing mortality was substantially underestimated in the mid-1980s, just before the demise of a cod stock that historically was the second largest in the northwest Atlantic.

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Nevalennyy, Aleksandr Nikolaevich, Tatiyana Sergeevna Ershova, Vyacheslav Fedorovich Zaitsev, and Vladimir Aleksandrovich Chaplygin. "Biogeochemical monitoring of composition of chemical elements in Caspian Sea." Vestnik of Astrakhan State Technical University. Series: Fishing industry 2022, no. 4 (December 30, 2022): 22–28. http://dx.doi.org/10.24143/2073-5529-2022-4-22-28.

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The aim of the research was to conduct biogeochemical monitoring of heavy metals composition in the ecosystem of the northwestern part of the Caspian Sea. The objects of the research were the water of the northwestern part of the Caspian Sea, bottom sediments, different types of crustaceans, mollusks, fish, as well as the Caspian seal. As a result of the research, metal concentrating aquatic organisms in the Caspian Sea were identified. Thus, gammarus accumulates Zn, shrimp – Cu, crab – Pb and Ni, balanus – Hg, Pb, Cd; mollusk Didacna accumulates mainly Zn, Cd, and Hg; mytilaster – Cu, Co; cerastoderma – Pb; vobla – Zn and Hg; benthophilus - Pb and Mn; needlefish – Cu, Pb, Cd, and sprat – Zn and Hg. Specific features of metal accumulation by hydrobionts have been found out: Zn, Pb and Cd are accumulated mainly by invertebrates; Cu, Co, Mn are accumulated to the greatest extent by representatives of Crustacea; Ni – by Mollusca species; Hg is accumulated to the greatest extent by vertebrates. There have been revealed the regularities in distribution of chemical elements concentrations in the organs and tissues of aquatic organisms occupying the tops of the trophic pyramids: Zn, Cu, Hg are predominantly accumulated in the liver, Co, Ni, Zn, Pb and Cd are accumulated in the kidneys, Pb, Co, Mn are accumulated in the gills, Hg – in muscle tissues. In Phoca caspica Pb accumulates in the adipose tissue and lungs, Hg, Cu, Zn, Mn, Cr, and Co – in the liver, and Pb, Cd and Ni – in the kidneys. Taking into account the calculated coefficients of chemical elements accumulation, it was inferred that Hg and Zn can accumulate in almost all links of the trophic chain; Cu, Co, Ni, Cd, Pb are accumulated mainly by invertebrates; Cr and Mn accumulate to a greater extent in bottom sediments.

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"Phoma tropica." CABI Compendium CABI Compendium (January 7, 2022). http://dx.doi.org/10.1079/cabicompendium.119161.

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Rai, Mahendra, Beata Zimowska, Aniket Gade, and Pramod Ingle. "Promising antimicrobials from Phoma spp.: progress and prospects." AMB Express 12, no. 1 (May 23, 2022). http://dx.doi.org/10.1186/s13568-022-01404-y.

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AbstractThe increasing multidrug-resistance in pathogenic microbes and the emergence of new microbial pathogens like coronaviruses have necessitated the discovery of new antimicrobials to treat these pathogens. The use of antibiotics began after the discovery of penicillin by Alexander Fleming from Penicillium chrysogenum. This has attracted the scientific community to delve deep into the antimicrobial capabilities of various fungi in general and Phoma spp. in particular. Phoma spp. such as Phoma arachidicola, P. sorghina, P. exigua var. exigua, P. herbarum, P. multirostrata, P. betae, P. fimeti, P. tropica, among others are known to produce different bioactive metabolites including polyketides, macrosporin, terpenes and terpenoids, thiodiketopiperazines, cytochalasin derivatives, phenolic compounds, and alkaloids. These bioactive metabolites have already demonstrated their antimicrobial potential (antibacterial, antifungal, and antiviral) against various pathogens. In the present review, we have discussed the antimicrobial potential of secondary metabolites produced by different Phoma species. We have also deliberated the biogenic synthesis of eco-friendly antimicrobial silver nanoparticles from Phoma and their role as potential antimicrobial agents.

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Punithalingam, E. "Phoma sorghina. [Descriptions of Fungi and Bacteria]." IMI Descriptions of Fungi and Bacteria, no. 83 (July 1, 1985). http://dx.doi.org/10.1079/dfb/20056400825.

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Abstract A description is provided for Phoma sorghina. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Gramineae and all kinds of plants. Also isolated from soil, air and various animal sources. DISEASE: A minor leaf spot of cereals and grasses. The visible symptoms vary considerably; on sorghum leaves spots are usually irregular or rounded, yellowish-brown or grey with definite reddish-purple margins or indefinite in outline, reaching 1 cm or more in width. Pycnidia develop within spots on leaves, glumes and seeds. Also the fungus has been implicated with pre- and post-emergence death of seedlings of Macroptilium and Sylosanthes species (54, 1779) crown rot of bananas (61, 3556), leaf spot of Agave americana and stem rot of Euphorbia tirucalli (63, 3383), brown stem canker of Leucosperum cordifolium (56, 253). GEOGRAPHICAL DISTRIBUTION: A ubiquitous fungus occurring in tropical and subtropical regions. Africa (Botswana, Cameroon, Egypt, Ethiopia, Gambia, Kenya, Malawi, Mauritius, Mozambique, Nigeria, Senegal, Sierra Leone, South Africa, Sudan, Tanzania, Togo, Uganda, Zaire, Zambia, Zimbabwe); Asia (Bangladesh, Brunei, Burma, China, Hong Kong, India, Indonesia (Irian Jaya), Laos, Malaysia, Nepal, Pakistan, Saudi Arabia, Sri Lanka, Taiwan, USSR); Australasia and Oceania (Australia, Hawaii, New Zealand, Papua New Guinea, Solomon Islands); Europe (Germany, Portugal, Italy, UK); North America (Canada, USA); Central America and West Indies (Antigua, Guatemala, Honduras, Jamaica, Nicaragua, Puerto Rico, Trinidad); South America (Argentina, Bolivia, Brazil, Colombia). TRANSMISSION: Probably by contaminated seed; the fungus has been found on or isolated from several seed samples (1, 289; 33, 599; 47, 2153; 54, 1779; 60, 367; 61, 4102). In Taiwan P. sorghina has been found to be transmitted from seed to seedlings (62, 4281). The fungus has also been claimed to persist on trash and weed hosts and remain viable up to 1 yr but lose its viability after 2 yr storage on dry infected leaves (Koch & Rumbold, 1921).

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Indawati, Rachmah. "Relation between Population Fluctuations and Dengue Cases in Pasuruan Region, Indonesia, 2013-2017." Public Health Open Access 6, no. 1 (2022). http://dx.doi.org/10.23880/phoa-16000202.

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Dengue Hemorrhagic Fever (DHF) is a tropical disease and its spread is very wide. Control of this disease is relatively easy, with community participation playing a vital role. However, the number of DHF cases is still high. A study reported that unhealthy behavior of the community contributed to the high incidence of the disease. In addition, environmental conditions also support the breeding of mosquitoes.

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Avelino, Anne Caroline Dallabrida, Dayana Aparecida de Faria, Lucas Dias de Oliveira, Yuri Nunes Cervo, Alexandre Secco Contreras Filho, Matheus Afonso Farinha, Onassis Henrique Simon Rondon, et al. "Fungi Associated with Major Agricultural and Forage Crops in Integrated Systems of Brazilian Tropical Regions." Journal of Experimental Agriculture International, July 30, 2019, 1–13. http://dx.doi.org/10.9734/jeai/2019/v39i530343.

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Integrated production systems were developed to preserve productive resources and maintain the profitability of agribusiness. However, the use of seeds of low physiological and sanitary quality and the implantation of agricultural and forage crops in production fields of low sanitary quality may favor the dissemination and proliferation of phytopathogens such as fungi. Therefore, using the scientific literature, this work aimed to identify the fungi associated with the main agricultural and forage crops that cause damage to the integrated production systems of Brazilian tropical regions and their control measures. This work was based on a literature review in the Scielo, Scopus and Google Scholar databases, with data obtained between 1999 and 2019. The keywords employed were “fungus”, “tropical grass”; “agricultural crops”; “ICLS” (Integrated Crop-Livestock); and “ICLF” (Crop-Livestock-Forest) and their respective terms in Portuguese, under different combinations. For the inclusion criteria, publications (papers, books, theses, dissertations, and scientific communiqués) from 1999 to 2019 which fit the study aim were selected, both in the Portuguese and English languages. The publications that did not meet the criteria of this study and were repeated in databases were considered as exclusion criteria. The main fungi associated with forage and agricultural crops and soils of integrated systems of Brazilian tropical regions are Bipolaris sp., Curvularia sp., Exserohilum syn. Helminthosporium sp., Phoma sp., Fusarium sp., Macrophomina sp., Pythium sp., Rhizoctonia sp. and Sclerotium sp. The main methods of fungal control are the use of quality seeds, crop rotation, resistant cultivars, and chemical seed treatment.

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Li, Yong, Haijiang Chen, Lan Ma, Youshan An, Hui Wang, and Wenneng Wu. "Laboratory Screening of Control Agents Against Isolated Fungal Pathogens Causing Postharvest Diseases of Pitaya in Guizhou, China." Frontiers in Chemistry 10 (June 30, 2022). http://dx.doi.org/10.3389/fchem.2022.942185.

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Pitaya, or dragon fruit, is a typical tropical fruit with an appealing taste and diverse health benefits to humans. The plantation of pitaya in Guizhou province in China has greatly boosted the income of local farmers and alleviated poverty. However, the frequent occurrence of postharvest diseases has brought large economic loss. To find a solution, we set out to identify the postharvest disease-causing agents of Guizhou pitaya. Several fungi were isolated from diseased pitaya and identified as species based on the ITS1 sequence similarity. Of them, Penicillium spinulosum, Phoma herbarum, Nemania bipapillata, and Aspergillus oryzae were, for the first time, found to cause dragon fruit disease. In consideration of their prevalence in postharvest fruit diseases, Alternaria alternata H8 and Fusarium proliferatum H4 were chosen as representative pathogens for the drug susceptibility test. Among the tested drugs and plant extracts, 430 g/L tebuconazole and 45% prochloraz were found to be the most potent fungicides against H8 and H4, respectively. The research provides insights into the mechanism and control of postharvest diseases of dragon fruits in Guizhou, China, and thus could be of economic and social significance to local farmers and the government.

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Silva, Airton Damasceno, Alessandra Regina Pepe Ambrozin, Ana Flávia S. de Camargo, Felipe De Paula Nogueira Cruz, Leonardo Luiz Gomes Ferreira, Renata Krogh, Taynara Lopes Silva, Ilana Lopes Baratella da Cunha Camargo, Adriano Defini Andricopulo, and Paulo Cezar Vieira. "Liquid Fungal Cocultivation as a Strategy to Access Bioactive Metabolites." Planta Medica, July 9, 2020. http://dx.doi.org/10.1055/a-1200-2046.

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AbstractFungi are a rich source of bioactive compounds. Fungal cocultivation is a method of potentiating chemical interactions and, consequently, increasing bioactive molecule production. In this study, we evaluated the bactericidal, antiprotozoal, and cathepsin V inhibition activities of extracts from axenic cultures of 6 fungi (Fusarium guttiforme, Pestalotiopsis diospyri, Phoma caricae-papayae, Colletotrichum horii, Phytophthora palmivora, and C. gloeosporioides) that infest tropical fruits and 57 extracts obtained by their cocultivation. Our results reveal that fungal cocultivation enhances the biological activity of the samples, since all extracts that were active on Gram-positive bacteria, Gram-negative bacteria, Trypanosoma cruzi, and Leishmania infantum were obtained from cocultivation. Bacterial growth is either totally or partially inhibited by 46% of the extracts. Two extracts containing mainly fusaric and 9,10-dehydrofusaric acids were particularly active. The presence of the fungus F. guttiforme in co-cultures that give rise to extracts with the highest activities against L. infantum. An axenic culture gave rise to the most active extract for the inhibition of cathepsin V; however, other coculture extracts also exhibited activity toward this biological target. Therefore, the results of the biological activities indicate that fungal cocultivation increased the biological potential of samples, likely due to the hostile and competitive environment that pushes microorganisms to produce substances important for defense and allows access to metabolic routes then silenced in milder cultivation conditions.

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Sills, Jillian M., and Colleen Reichmuth. "Vocal Behavior in Spotted Seals (Phoca largha) and Implications for Passive Acoustic Monitoring." Frontiers in Remote Sensing 3 (May 23, 2022). http://dx.doi.org/10.3389/frsen.2022.862435.

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Passive acoustic methods enable remote monitoring of marine species and habitats. These methods can be applied to investigate distribution and abundance of populations, to evaluate behavioral and physiological states of individuals, and to inform management efforts for animals that live in hard-to-reach places. Spotted seals (Phoca largha) inhabit high-latitude, light-limited sub-Arctic and Arctic waters and move seasonally with unstable sea ice. They are high trophic level predators vulnerable to changing conditions associated with environmental warming. At present, an incomplete characterization of the spotted seal vocal repertoire limits our ability to monitor this species acoustically. Captive studies can inform passive acoustic efforts by describing fundamental features of species-typical vocalizations emitted by known individuals. These features include acoustic parameters as well as developmental, seasonal, and sex-specific patterns in vocal behavior. Here, we studied several male spotted seals in captivity from age 6 months through adulthood (10 years). Vocal behavior was scored daily and opportunistically recorded. The production of underwater calls emerged during sexual maturation, at age 4. To evaluate vocal repertoire and fine-scale temporal patterns of sound production in adult seals, an underwater acoustic recorder was continuously deployed with two seals at age 7 years. The spotted seals produced at least eight distinctive underwater call types with dominant energy below 1 kHz. The amplitude of the most common vocalization was ∼140 dB re 1 μPa (sound pressure level at 1 m). There was a marked peak in vocal activity in springtime, prior to onset of the annual molt. This period coincided with increased aggressive behavior, presence of a notable musky odor, and urogenital swelling indicative of heightened reproductive status. These results from developing male spotted seals reared in human care confirm the production of recognizable, stereotypic underwater calls associated with the breeding season. Description of vocal behavior improves knowledge of this species’ biology, and informs the potential use of autonomous acoustic recorders to track the presence and movements of free-ranging spotted seals in remote habitats.

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Thomas, Austen C., Bruce Deagle, Chad Nordstrom, Sheena Majewski, Benjamin W. Nelson, Alejandro Acevedo-Gutiérrez, Steven Jeffries, et al. "Data on the diets of Salish Sea harbour seals from DNA metabarcoding." Scientific Data 9, no. 1 (March 2, 2022). http://dx.doi.org/10.1038/s41597-022-01152-5.

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AbstractMarine trophic ecology data are in high demand as natural resource agencies increasingly adopt ecosystem-based management strategies that account for complex species interactions. Harbour seal (Phoca vitulina) diet data are of particular interest because the species is an abundant predator in the northeast Pacific Ocean and Salish Sea ecosystem that consumes Pacific salmon (Oncorhynchus spp.). A multi-agency effort was therefore undertaken to produce harbour seal diet data on an ecosystem scale using, 1) a standardized set of scat collection and analysis methods, and 2) a newly developed DNA metabarcoding diet analysis technique designed to identify prey species and quantify their relative proportions in seal diets. The DNA-based dataset described herein contains records from 4,625 harbour seal scats representing 52 haulout sites, 7 years, 12 calendar months, and a total of 11,641 prey identifications. Prey morphological hard parts analyses were conducted alongside, resulting in corresponding hard parts data for 92% of the scat DNA samples. A custom-built prey DNA sequence database containing 201 species (192 fishes, 9 cephalopods) is also provided.

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Planque, Yann, Jérôme Spitz, Matthieu Authier, Gaël Guillou, Cécile Vincent, and Florence Caurant. "Trophic niche overlap between sympatric harbour seals ( Phoca vitulina ) and grey seals ( Halichoerus grypus ) at the southern limit of their European range (Eastern English Channel)." Ecology and Evolution, July 5, 2021. http://dx.doi.org/10.1002/ece3.7739.

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Journal articles on the topic 'Phoma tropica'

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