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Relação filogenética, por ITS-rDNA, de Colletotrichum spp., agente causal da mancha foliar da gala em macieira / Phylogenetic relationship by ITS-rDNA of Colletotrichum spp. causal agent of apple glomerella leaf spotRibeiro, Diorvania Cardoso 26 February 2007 (has links)
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Previous issue date: 2007-02-26 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The apple is a temperate clime fruit with larger dispersion, consumption and the more
marketed all over the world as fresh fruit. The apple production has been committed by the
incidence of diseases, in which Apple Leaf Spot (ALS), whose causal agent is the
Colletotrichum spp. Nowadays this disease is one of the largest concerns of the producers and
researchers. The origin of this disease in apple tree plants is not still well known. Studies
based on the phylogeny allow to relate evolutionarily the organisms and characterize possible
divergence mechanisms origin. This will contribute in disease control and prevention of new
races sprout. The objective of this work was to study the variation of the ITSs rDNA among
apple tree pathogenic isolates of Colletotrichum spp. from apple, citrus and feijoa. All isolates
were first cultivated on PDA, for one week at 24oC. In the PCR amplification of the rDNA
was used initiators ITS1 and ITS4. The amplified fragment was digested with restriction
enzymes (Rsa I, Alu I, Hinf I, Hpa II, Hha I, Xho I, Acc I, Eco RI and Taq I). The revelation
was in 2% agarose gel. It was obtained a great variation with products of the cleaved PCR
products, from 90 to 500 pb. The amplified fragment was purified (QIAquick Gel Extraction
Kit 250 - Unisciense of Brazil) and the fragment (ITS of the rDNA) was sequenced for all
isolates. The sequences were aligned with the ClustalW software and the phylogenetic tree
was constructed in the Mega 3.1 software. The products obtained in the PCR amplification of
the rDNA region (ITS1-5,8S-ITS2), with the initiators pair ITS1 and ITS4 revealed a
fragment with approximately 600 pb, for all the isolated analyzed. Through the analysis for
the ARDRA was possible to separate isolates groups in haplotypes, which was efficient for
the correlation between haplotypes and hosts, containing in a same haplotypes of the same
host. It was possible to group the isolates of Colletotrichum in species, using the phylogenetic
tree, independent of his host. All of the obtained sequences presented more than 93% of
similarity, fact that reinforces the hypothesis that the Colletotrichum spp., causal agent of
ALS, is nearly related with citrus and feijoa Colletotrichum / A maçã é a fruta de clima temperado de maior dispersão, consumo e a mais
comercializada como fruta fresca em todo o mundo. A produção de maçã no Brasil tem sido
comprometida pela incidência de várias doenças, das quais a Mancha Foliar da Gala (MFG),
cujo agente causal são espécies de Colletotrichum spp., tem sido, atualmente, uma das
maiores preocupações dos produtores e pesquisadores. A origem desta doença em macieira
ainda não está bem esclarecida e a utilização de estudos baseados na filogenia permitem
relacionar os organismos evolutivamente, caracterizando possíveis mecanismos de
divergência evolutiva e a origem do patógeno, contribuindo na adoção de medidas de controle
e prevenção quanto ao surgimento de novas raças. O presente trabalho objetivou estudar a
variação do DNA ribossomal, (rDNA) entre isolados de Colletotrichum spp. patogênicos em
macieira, em citros e goiaba serrana. Todos os isolados foram cultivados em meio BDA, por
uma semana a 24oC. A amplificação do rDNA foi realizada utilizando-se iniciadores ITS1 e
ITS4, seguida pela digestão da região ITS (espaçador interno transcrito) com enzimas de
restrição (Rsa I, Alu I, Hinf I, Hpa II, Hha I, Xho I, Acc I, Eco RI e Taq I). Os produtos
obtidos na amplificação da região ITS1-5,8S-ITS2 do rDNA revelaram um fragmento de
aproximadamente 600 pares de bases (pb), para todos os isolados analisados. Todos os
fragmentos amplificados foram clivados, obtendo uma grande variação, a qual foi de 90 a 500
pb. Utilizando a técnica de ARDRA (Amplified Ribosomal DNA Restriction Analysis) foi
possível separar e agrupar os isolados em haplótipos, a qual foi eficiente para a correlação
entre haplótipo e hospedeiros, agrupando em um mesmo haplótipo isolados do mesmo
hospedeiro. O fragmento amplificado foi purificado com kit QIAquick Gel Extraction Kit 250
(Qiagen, Hilden, Germany) e as amostras foram seqüenciadas na região ITS do rDNA de todos
os isolados. As seqüências foram alinhadas no software ClustalW e a árvore filogenética foi
construída no software Mega 3.1. Com o seqüenciamento de DNA foi possível inferir sobre a
possível espécie de fungo que pertence o segmento de DNA analisado. A região ITS do rDNA
mostrou-se muito eficaz para estudos de filogenia. A partir da árvore filogenética foi possível
agrupar os isolados de Colletotrichum por espécies, independente do seu hospedeiro. Todas as
seqüências obtidas apresentaram valores superiores a 93% de similaridade, fato esse, que
reforça que o Colletotrichum spp., causador da MFG, possui relações de parentesco com o
isolados de Colletotrichum spp. isolados de citros e de goiaba serrana
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Intensidade de Mancha de Glomerella em macieira com a aplicação de inibidores da síntese e ação do etileno / Glomerella spot intensity with the application of inhibitors of ethylene synthesis and action in appleBaldin, Bruna Moreira Schrammel 12 December 2014 (has links)
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Previous issue date: 2014-12-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O aumento na cadeia produtiva da maçã levou-nos a alguns problemas, pois a maturação dos frutos se encontra em um curto período de tempo. Como alternativa, utiliza-se inibidores da síntese (aminoetoxivinilglicina; AVG) e ação (1-metilciclopropeno; 1-MCP) do etileno, que possibilitam o escalonamento da colheita e reduzem a queda pré-colheita de maçãs. Porém, o AVG, segundo alguns estudos, tem ocasionado o aumento da suscetibilidade das folhas a Mancha de Glomerella (MFG). Portanto, este trabalho teve como objetivo verificar se há uma relação direta dos compostos AVG e 1-MCP sobre o desenvolvimento do patógeno causador da MFG; avaliar o efeito do tratamento pré-colheita com AVG e 1-MCP na suscetibilidade de macieiras Gala a MFG; e comparar a resposta da aplicação pré-colheita de AVG e 1-MCP em folhas de macieira Gala , na ocorrência de MFG e de doenças pós-colheita nos frutos. O estudo foi realizado em Vacaria-RS na safra 2013/2014. Nos experimentos in vitro, determinou-se as unidades formadoras de colônia (UFC) e o crescimento micelial com tratamentos de AVG e 1-MCP, ambos nas concentrações 0, 10, 30, 90 e 270 mg i.a L-1. Nos frutos, folhas destacadas e plântulas aplicou-se os compostos de AVG (125 mg i.a L-1) e 1-MCP (150 mg i.a L-1), dois dias antes e dois dias após a inoculação. Os frutos foram armazenados por 15 dias em câmara BOD a 22 ± 2 °C, e avaliados quanto ao número de lesões/fruto. As folhas
destacadas e plântulas foram mantidas por 24 horas em câmara úmida após a inoculação, e avaliadas quanto à incidência e severidade da doença no sétimo dia após inoculação. Em mudas de macieira Gala , sobre porta-enxerto EM9, com um ano de idade, os tratamentos foram realizados dois dias antes da inoculação com o patógeno, sendo utilizado os compostos AVG e 1-MCP, ambos nas doses 125 e 250 mg i.a L-1. Avaliou-se a incidência e severidade de MFG aos 7, 9, 12, 14, 16 e 19 dias após inoculação. Para a avaliação do efeito do AVG e 1-MCP no campo, utilizou-se dois pomares, um de três anos de idade e outro de 15 anos de idade, sendo que a aplicação de ambos os compostos se deu em duas concentrações, 125 e 250 mg i.a L-1, realizadas em dois estádios fenológicos, sendo eles aos 28 e 7 dias antes da data prevista para a colheita. Avaliou-se a incidência e severidade da doença quinzenalmente, durante os meses de janeiro a maio de 2014. A utilização dos compostos AVG e 1-MCP não interferiram no desenvolvimento da colônia em condições in vitro. Nos frutos a utilização dos compostos inibidores da síntese/ação do etileno, proporcionou um aumento na incidência da doença, quando a aplicação antecedeu a inoculação. Houve uma maior incidência da MFG, quando a inoculação ocorre após a aplicação do AVG. O 1-MCP apresentou níveis menores de severidade de MFG em relação ao AVG. A utilização no pomar de AVG e 1-MCP na safra de 2013/2014 não provocou um aumento significativo na incidência e severidade de MFG, devido às condições climáticas não favoráveis para a ocorrência da doença
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Biološko suzbijanje Colletotrichum spp. parazitauskladištenih plodova jabukeGrahovac Mila 28 May 2014 (has links)
<p>Colletotrichum spp. su značajni prouzrokovači bolesti biljaka u svetu i u našoj zemlji, u polju i u skladištu. Na plodovima jabuke prisutne su dve vrste ovog roda, C. acutatum i C. gloeosporioides. Pomenute vrste uzrokuju ekonomski značajne gubitke posle berbe plodova jabuke, tokom skladištenja, transporta i plasmana na tržište. Nedoumice sa kojima se naučna javnost suočava kada je u pitanju ovaj rod jeste precizno utvrđivanje sistematske pozicije i definisanje vrsta i nižih kategorija. Klasične fitopatološke metode ne omogućavaju preciznu<br />iv<br />identifikaciju do nivoa vrste. Otuda su molekularni pristupi sve zastupljeniji u identifikaciji Colletotrichum spp. U suzbijanju skladišnih patogena pretežno se primenjuju hemijski fungicidi. Zbog nepovoljnih toksikoloških svojstava i pojave rezistentnosti, primena hemijskih fungicida se sve više redukuje, a njihova upotreba posle berbe plodova zabranjena je u većini zemalja. Stoga, za održivi razvoj poljoprivredne proizvodnje neophodna su istraživanja usmerena ka otkrivanju mikroorganizama i prirodno sintetisanih materija koje imaju potencijala za primenu u biološkoj zaštiti.<br />Cilj ovog rada je da se utvrdi zastupljenost Colletotrichum spp. na uskladištenim plodovima jabuke u R. Srbiji, kao i pouzdanost klasičnih i molekularnih metoda za njihovu identifikaciju do nivoa vrste i nižih kategorija. Utvrđivanje filogenetske pozicije i genetičke udaljenosti izolata je takođe svrstano u ciljeve istraživanja. Nadalje, cilj je i da se izdvoje mikroorganizami i etarska ulja koja ispoljavaju antifungalno delovanje na Colletotrichum spp. Zatim, da se za mikroorganizam sa najizraženijim antifungalnim delovanjem definišu uslovi kultivacije (sastav hranljive podloge i trajanje) koji maksimizuju njegovu antifungalnu aktivnost i utvrdi način njegovog delovanja.<br />Utvrđeno je da su Colletotrichum spp. redovno prisutni na uskladištenim plodovima jabuke u Vojvodini i delovima zapadne, centralne i jugoistočne Srbije i da je njihova zastupljenost u odnosu na druge fitopatogene gljive 7,8-10%. Zbog osetljivosti C. gloeosporioides na niske temperature, C. acutatum postaje sve dominantnija vrsta ovog roda na uskladištenim plodovima jabuke. Razlikovanje C. acutatum i C. gloeosporioides je moguće na osnovu fenotipskih karakteristika kolonija (u slučaju hromogenih izolata C. acutatum), dužine konidija, rasta kolonija na 5 i 35°C i brzine rasta kolonija na različitim podlogama. Oblik i širina konidija i optimalna temperatura rasta su nedovoljno pouzdani kriterijumi za identifikaciju do nivoa vrste. PCR metodom uz primenu prajmera specifičnih za vrstu uspešno se identifikuju C. acutatum i C. gloeosporioides. Primenom univerzalnih prajmera ITS1 i ITS4 amplifikuju se rDNK-ITS sekvence ovih izolata. Analizom sekvenci izrađuju se filogenetska stabla visoke stabilnosti i jasno razdvajaju C. acutatum i C. gloeosporioides, a u okviru C. acutatum se odvajaju nehromogeni i hromogeni izolati. S. hygroscopicus, S. aureus, B. cereus, P. aeruginosa i B. subtilis sojevi N146, ST 1/III, Č13 i QST 713 ispoljavaju antifungalnu aktivnost na Colletotrichum spp. in vitro i in vivo. S. hygroscopicus obezbeđuje zaštitu plodova na nivou sa hemijskim fungicidima (trifloksistrobin, boskalid+piraklostrobin, pirimetanil+flukvinkonazol, kaptan). Kultivacijom S. hygroscopicus u podlozi sa 15,07 g/l glicerola, 5,28 g/l ekstrakta kvasca i 0,81 g/l fosfata, u<br />v<br />trajanju 3-4 dana, postiže se maksimalno antifungalno delovanje na Colletotrichum spp. Antifungalno delovanje S. hygroscopicus zasnovano je na produkciji ekstracelularnih, termostabilnih metabolita. Dvomesečno skladištenje trtiranih plodova na 2±0,5°C ne slabi antifungalno delovanje S. hygroscopicus. Etarska ulja origana i timijana ispoljavaju snažno inhibitorno delovanje na Colletotrichum spp.</p> / <p>Colletotrichum spp. are significant plant pathogens worldwide in field, as well as on stored fruits. Two species of this genera, C. acutatum and C. gloeosporioides, can occur on apple fruits. The species cause significant economic losses on apple fruits after harvest, during storage, transport and marketing. Scientific community faces confusion in defining precise systematic position of this genera, as well as in identification to the species level and lower categories. Conventional<br />viii<br />phytopathological methods do not provide precise identification to the species level. Thus, molecular approaches are taking the lead in Colletotrichum spp. identification. Post-harvest pathogens are mainly managed by chemical fungicides. Due to adverse toxicological properties and resistance occurrence, use of chemical fungicides is being reduced, and their application after harvest is prohibited in most countries. Therefore, studies regarding detection of microorganisms and naturally synthetized substances with a potential for application in biological control are necessary for sustainable development of agriculture.<br />The aim of this study was to determine frequency of Colletotrichum spp. on stored apple fruits in the Republic of Serbia as well as reliability of conventional and molecular methods in their identification to the species level and lower categories. Determination of phylogenetic position and molecular distance of the isolates were also set as investigation goals. The aim was also to determine microorganisms and essential oils with antifungal activity against Colletotrichum spp. Defining of cultivation conditions (nutrient medium composition and duration) for the microorganism with the most pronounced antifungal activity which maximize its activity and defining its mode of action were also set as goals.<br />It was found that Colletotrichum spp. are commonly present on stored apple fruits in Vojvodina Province and in western, central and southeastern parts of Serbia with a share of 7.8-10% among other phytopathogenic fungi. Due to susceptibility of C. gloeosporioides to low temperatures, C. acutatum is becoming dominant species of this genus on stored apple fruits. Discrimination between C. acutatum and C. gloeosporioides is possible on the basis of phenotypic characteristics of colony (in the case of chromogenus isolates of C. acutatum), conidium length, colony growth at 5 and 35°C and colony growth rate on different media. Conidium shape and width and optimal growth temperature are insufficient criteria for identification to the species level. PCR method using species-specific primers is reliable for identification of C. acutatum and C. gloeosporioides. rDNK-ITS sequences of the isolates can be successfully amplified with universal primers, ITS1 and ITS4. Analyses of the sequences alow construction of highly stable phylogenetic trees with distinctively separated C. acutatum and C. gloeosporioides clades, and also additional clades of non-chromogenum and chromogenum C. acutatum isolates. S. hygroscopicus, S. aureus, B. cereus, P. aeruginosa and B. subtilis strains N146, ST 1/III, Č13 and QST<br />ix<br />713 exhibit antifungal activity against Colletotrichum spp. in vitro and in vivo. S. hygroscopicus ensures fruit protection at the same level as chemical fungicides (trifloxistrobin, boscalid+pyraclostrobine, pyrimethanil+flukvinconazol, captan). Cultivation of S. hygroscopicus in the medium with 15.07 g/l glycerol, 5.28 g/l yeast extract and 0.81 g/l phosphates, for 3-4 days, ensures maximal antifungal activity against Colletotrichum spp. Antifungal activity of S. hygroscopicus is based on production of extracelular, thermostable metabolites. Two-month storage of treated apple fruits at 2±0.5°C does not reduce antifungal activity of S. hygroscopicus. Oregano and thyme essential oils exhibit strong inhibitory effects on Colletotrichum</p>
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Produção, qualidade e sanidade de frutos de bananeira 'BRS Conquista' ensacados com polipropileno de diferentes cores / Production, quality and sanitation of banana plants 'BRS Conquista' bagged with polipropilen of different colorsMartins, Rafaelly Calsavara 23 February 2018 (has links)
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Previous issue date: 2018-02-23 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A bananeira é a segunda fruta com maior volume comercializado no mundo. Pelo fato de ser uma fruta muito apreciada pelo consumidor brasileiro, nos últimos anos surgiram diversas tecnologias que auxiliam no cultivo da bananeira, principalmente relacionadas à qualidade dos frutos. Nesse contexto, o trabalho teve como objetivo avaliar a influência da coloração dos sacos plásticos empregados no ensacamento de cachos de bananeira ‘BRS Conquista’. Os tratamentos consistiram no uso de sacos de polietileno comerciais, nas cores branco, preto, vermelho e azul, além da testemunha (sem ensacamento). O delineamento experimental foi em blocos casualizados, com cinco tratamentos, quatro repetições e quatro plantas por parcela, totalizando 80 plantas. Avaliou-se a qualidade fitossanitária dos frutos, sendo o número de pontuações de danos causados por tripes da erupção e a porcentagem de área lesionada causada por antracnose, além das características físicas dos frutos, como massa do cacho, massa da ráquis, massa dos frutos, número de frutos por cacho, número de pencas por cacho, massa das pencas, número, comprimento e diâmetro de frutos da segunda penca, e as características físico-químicas dos frutos, como sólidos solúveis, acidez titulável, relação polpa/casca, índice de maturação e período de maturação. Verificou-se que os cachos que foram ensacados com sacos de coloração branca e preto apresentaram menor número de pontuações provocadas por tripes. Enquanto que para antracnose, os cachos que receberam sacos de coloração branca, vermelha e azul, apresentaram as menores porcentagens de área lesionada. O ensacamento dos cachos com sacos plásticos de diferentes colorações não interferiu nas variáveis produtivas. Contudo, nos cachos que não receberam ensacamento observaram-se maiores teores de sólidos solúveis que naquelas ensacadas. / Banana is the second most commercialized fruit crop in the world. Since it is very appreciated by the Brazilian consumer, in the last years, several technologies have come out to help in the development of the crop, mainly related to the quality of fruits. In this context, the objective of this work was to use banana bagging techniques for improvements in the banana cultivation process. Polyethylene bags of white, black, red, blue colors and the control (no bagging) were used in this technique. A randomized complete block design with five treatments, four replications, two plants per plot, totaling 80 plants was used. The evaluated characteristics in the post-harvest were the bunch mass, fruit mass, number of fruits per bunch, bunch number, second bunch mass, number of fruits of second batch, length, diameter, pH, soluble solids, titratable acidity, pulp/peel ratio, maturation index and maturation days. The phytosanitary quality of the fruits was evaluated, and the symptoms of thrips and anthracnose were assessed. In addition, the physical characteristics of the fruit, which is represented by the mass of the bunch, mass of the rachis, mass of the fruit, number of fruit per bunch, number of penca by bunch, productivity, mass of the second bunch, number of fruit in the second bunch, length and diameter of the fruit in the second bunch and physical chemical characteristics of the fruit, soluble solids, acidity, relation pulp/peel, index of maturation and period of maturation were evaluated. It was verified that for the variable mass of the second bunch, the white and black bags presented better results, whereas for pH variable the blue staining was the one which showed better results, and for the soluble solids it was the control group. This work showed that the efficiency of bagging is associated with the type and color of the bag which is used, since the coverings assign a thermal role inside the bunches / 130371/2016-5
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Phylogeny, histological observation, and in vitro fungicide screening and field trials of multiple Colletotrichum species, the causal agents of grape ripe rotOliver, Charlotte 31 January 2019 (has links)
Colletotrichum acutatum and C. gloeosporioides are fungal plant pathogens that have a global distribution, extensive host range, and convoluted taxonomy. Both species can cause grape ripe rot and are considered endemic to Virginia US. In 2012, C. acutatum and C. gloeosporioides were reclassified into species complexes that consist of 31 and 22 accepted species, respectively. The objectives of this study were to: 1) survey Virginia vineyards for grape ripe rot, and morphologically and phylogenetically identify isolates to the species within the complexes, 2) conduct an in vitro fungicide assay to screen fifteen commercial fungicides and combinations of two fungicides for efficacy to control isolates from seven Colletotrichum species from Virginia vineyards, 3) sequence gene fragments from three subunits of the SDH enzyme in the fungicide-screened isolates to observe potential resistance mutations, 4) investigate the susceptibility of three grapevine tissues to Colletotrichum species, 5) observe potential infection structures before and after the application of fungicides, 6) evaluate the efficacy of commercial fungicide controls of grape ripe rot in the field, and determine the most advantageous timing of applications. In my studies, I identified six Colletotrichum species: C. aenigma, C. conoides, C. fioriniae, C. gloeosporioides, C. kahawae, and C. nymphaeae. I also found two additional groups; an isolate similar to C. limetticola and C. melonis and a group of isolates that are similar to C. alienum, C. fructicola, and C. nupharicola. I also identified captan, and mancozeb as two potential active ingredients for control of grape ripe rot isolates from Virginia via the in vitro fungicide assay. Additionally, I found that combinations of two active ingredients could increase the efficacy of benzovindiflupyr, copper, and polyoxin-D. C. fioriniae germination and production of melanized appressoria was documented on leaves. I observed appressorium formation with isolates of two C. fructicola-like genotypes and C. nymphaeae, as well as secondary conidiation with isolates of C. aenigma, C. fructicola-like genotype 3, and C. nymphaeae on blooms. And finally, benzovindiflupyr, cyprodinil + fludioxonil pre-mix, and potassium phosphite + tebuconazole were identified as candidates for chemical control for grape ripe rot in the field. / PHD / Colletotrichum acutatum and C. gloeosporioides are two fungal plant pathogens that are found on a wide range of crops around the globe. Both fungal species cause the disease grape ripe rot and have been found in Virginia (VA) USA since the late 1800s. Originally, grape ripe rot was considered a minor disease in VA; however, based on communications with local VA vineyard managers, grape ripe rot was found to cause up to 30% direct crop loss. Further indirect economic loss occurs during wine production due to the production of unpalatable, tobacco-like, off flavors from the infected grapes. Sensory studies found this wine flavor change occurred with as little as 3% of the total crushed grapes being infected. Grape ripe rot appears as a sunburn-like, tan injury on the surface of white-fruited grape berries. As the disease progresses, the dark injury expands across the surface of the berry and rings of salmon-colored spore masses form. On red-fruited grapes, the formation of spore masses is usually the first observable sign. Over time, the infected berries will shrivel down to a soft, pustule-covered raisin. Both C. acutatum and C. gloeosporioides cause the same grape ripe rot symptoms on fruit and overlap in fungal appearance. In addition, investigations of these pathogens using molecular techniques have revealed that each consists of a number of genetically distinct groups that are difficult to distinguish by appearance. Therefore, in 2012, C. acutatum and C. gloeosporioides were reclassified into 31 and 22 newly accepted species, respectively, using molecular techniques.
The objectives of this study were to: 1) survey VA vineyards for grape ripe rot, and visually and molecularly identify isolates to the species within the new complexes, 2) conduct a laboratory fungicide assay to screen fifteen commercial fungicides and combinations of two fungicides for control of isolates from VA vineyards, 3) sequence gene fragments from three subunits of the SDH enzyme in the fungicide-screened isolates to observe potential resistance mutations, 4) investigate the susceptibility of three grapevine tissues to Colletotrichum species, 5) observe potential infection structures before and after the application of fungicides, 6) evaluate the efficacy of commercial fungicide controls of grape ripe rot in the field, and determine the most advantageous timing of applications. In my studies, I identified six Colletotrichum species: C. aenigma, C. conoides, C. fioriniae, C. gloeosporioides¸ C. kahawae, and C. nymphaeae. I also found two additional groups; an isolate similar to C. limetticola and C. melonis and a group of isolates that are similar to C. alienum, C. fructicola, and C. nupharicola. Our lab also identified four active ingredients as potential controls of grape ripe rot in the laboratory fungicide assay; captan, mancozeb, tetraconazole and thiophanate-methyl. Additionally, combinations of two compounds can increase the effectiveness of benzovindiflupyr, copper, and polyoxin-D. of C. fructicola-like isolates, and C. nymphaeae formed infection structures on blooms. of C. aenigma, C. fructicola-like genotype 3, and C. nymphaeae formed spores on blooms without producing symptoms. C. fioriniae spores germinated and produced infection structures on leaves without producing symptoms.
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Qualidade de sementes e óleos essenciais de erva doce de plantas não atacadas e atacadas pelo pulgão e a influência dos seus óleos essenciais no controle da antracnose em manga ‘palmer’Silva, Rosana Sousa da 18 December 2015 (has links)
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Previous issue date: 2015-12-18 / Financiadora de Estudos e Projetos - Finep / Fennel (Foeniculum vulgare Mill.) is an importante crop for family farms. Its seed is used in the culinary and has medicinal properties, also produces the essential oil, which has been widely used due to its high antioxidant, antimicrobial, and insecticidal activity. However, fennel plants are susceptible to attack by the aphid Hyadaphis foeniculi (Pass.) (Hemiptera: Aphididae), which can decrease seeds quality. The aim of this study was to characterize seed and essential oil of fennel, from plants non-attacked and attacked by aphids, and to assess the potential of each essential oil associated with jackfruit (Artocarpus heterophyllus L.) seed starch coatings as an antifungal agent against Colletotrichum gloeosporioides, common desease in postharvest mango (Mangifera indica). The differences between seeds non-attacked and attacked by aphids, it was evaluated the profile of total and free amino acids, total and soluble protein content, activities of peroxidase (POD), polyphenol oxidase (PPO), and phenylalanine ammonia lyase (PAL), inhibitory activity of protease, electrophoretic profile of protein, total extractable polyphenols (TEP), yellow flavonoids and total antioxidant activity (TAA) by free radical capture DPPH• and ABTS•+ radical, profile of phenolic compounds, total lipids and fatty acid profile. The essential oils from two seeds were differentiated by the volatile compounds profile. The potential of essential oils as antifungal agents was verified in vitro tests at six concentrations (0.0; 0.05; 0.1; 0.2; 0.3 and 0.5% v/v) for inhibition of C. gloeosporioides in order to determine the minimum inhibitory concentrations (MIC) and the use of the MIC of each essential oil associated with jackfruit seed starch coating applied on mango to evaluate its ability to protect against this fungus and the quality through the parameters: firmness, titratable acidity (TA), soluble solids (SS), SS/TA and pH. Non-attacked fennel seeds by aphid showed higher contents of free amino acids, soluble protein, activities of POD and PPO, TEP, yellow flavonoids and TAA, while the activity of PAL and inhibition of protease were higher in attacked seed. Significant differences were observed in the amino acid profile, electrophoretic profile of proteins and in the profile of phenolic compounds from these seeds, however the fatty acid profile was not affected. There was a significant difference to the profile of volatile compounds, with the highest amount of phenylpropanoids in attacked seeds by aphids. The MIC for two types of essential oils was at 0.5%. The combination of coatings with essential oils showed similar behavior to the quality in „Palmer‟ mangoes and the anthracnose prevention, coatings with essential oil from attacked seed by the aphids was more effective reducing the injury. The attack of aphid on fennel seeds compromises the nutritional quality for food use, however, the essential oil from this from seed can be used to inhibit the incidence and severity of anthracnose on the mango, providing an alternative use of attacked seeds that has low commercial value. / A erva-doce (Foeniculum vulgare Mill.) é uma cultura de grande importância na agricultura familiar. Sua semente é utilizada na culinária e possui propriedades medicinais, além de produzir óleo essencial, que tem sido utilizado devido sua atividade antioxidante, antimicrobiana e inseticida. Porém, a cultura da erva-doce é susceptível ao ataque do pulgão Hyadaphis foeniculi (Pass.) (Hemiptera:Aphididae), que pode prejudicar a qualidade das sementes. O objetivo deste estudo foi caracterizar a semente e o óleo essencial de erva-doce, oriundos de plantas não atacadas e atacadas pelo pulgão, bem como a avaliar a potencialidade de cada óleo essencial associado a recobrimentos a base de amido de semente de jaca (Artocarpus heterophyllus L.) como agente antifúngico contra o agente patógeno Colletotrichum gloeosporioides, comum na pós-colheita de manga (Mangifera indica). As diferenças entre as sementes não atacadas e atacadas pelo pulgão foram determinadas através do perfil de aminoácidos totais e livres, conteúdo de proteína total e solúvel, atividade das enzimas peroxidase (POD), polifenoloxidase (PPO) e fenilalanina amônio liase (PAL), inibição de protease, perfil eletroforético de proteínas, polifenóis extraíveis totais (PET), flavonoides amarelos, atividade antioxidante total (AAT) através da captura dos radicais livres DPPH• e ABTS•+, perfil de compostos fenólicos, lipídeos totais e perfil de ácidos graxos. Os óleos essenciais das duas sementes foram diferenciados através do perfil dos compostos voláteis. A potencialidade dos óleos essenciais como agentes antifúngicos foi verificada através de testes in vitro em seis concentrações (0,0; 0,05; 0,1; 0,2; 0,3 e 0,5 % v/v) para inibição do C. gloeosporioides, a fim de determinar as concentrações inibitórias mínimas (CIM) e a utilização da CIM de cada óleo essencial associada a recobrimento de amido de semente de jaca aplicado em manga para verificar sua capacidade de proteção contra este fungo e atuação nos parâmetros de qualidade: firmeza, acidez titulável (AT), sólidos solúveis (SS), relação SS/AT e pH. As sementes de erva-doce não atacadas por pulgão apresentaram maiores quantidades de aminoácidos livres, proteínas solúveis, atividade enzimática da POD e PPO, PET, flavonoides amarelos e AAT, enquanto a atividade enzimática da PAL e inibição de protease foram superiores em semente atacada. Foram observadas diferenças significativas no perfil de aminoácidos, perfil eletroforético de proteínas e perfil de compostos fenólicos entre estas sementes, entretanto o perfil de ácidos graxos das sementes não foi afetado. Houve diferença significativa para o perfil de compostos voláteis, que apresentou maior quantidade de fenilpropanóides na semente atacada pelo pulgão. A CIM para os dois tipos de óleos essenciais, foi verificada na concentração de 0,5%. A associação dos recobrimentos com os óleos essenciais apresentou comportamento semelhante para as características de qualidade em manga „Palmer‟ e em relação à prevenção da antracnose, o recobrimento com óleo essencial de semente de erva-doce atacada pelo pulgão foi mais efetivo na redução da gravidade da lesão. O ataque do pulgão em erva-doce compromete a qualidade nutricional das sementes para uso alimentar, porém, o óleo essencial desta semente pode ser utilizado para inibir a incidência e severidade da antracnose em manga, fornecendo uma alternativa para a utilização de sementes atacadas, que tem baixo valor comercial.
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Developing Novel Management Options for Pear Fire Blight and Apple Bitter Rot with Characterization of Apple European Canker in VirginiaCorrea Borba, Matheus 27 June 2024 (has links)
In the realm of tree fruit cultivation, the management of various diseases affecting pome fruits like apples and pears is crucial for sustaining production. This study amalgamates findings from three distinct disease investigations to propose an integrated approach to their management. Firstly, in pursuit of mitigating shoot blight severity caused by Erwinia amylovora and preventing fire blight cankers on pear trees, a two-year evaluation was conducted. The study assessed the efficacy of preventive treatments, including foliar spray and trunk injection applications of Giant Knotweed Extract (RSE) alongside antibiotics. Results highlighted the effectiveness of RSE in controlling both shoot blight severity and canker incidence, offering a sustainable alternative to antibiotics. Secondly, in addressing the bitter rot of apples caused by Colletotrichum spp., eighteen fungicide treatments were evaluated over two years, focusing on newer fungicide options to mitigate fungicide resistance development. Fungicides such as Omega, Aprovia, Ferbam, Captan, Ziram, and Cabrio were proven reliable management tools, complementing the existing effective fungicides that growers heavily depend on. Lastly, the emergence of European canker (Neonectria ditissima) on cider apple cultivars was investigated. Molecular analysis confirmed the presence of N. ditissima as the causal agent, posing a significant threat to cider apple production. Koch's postulates were fulfilled through various tests, proving the pathogenicity of N. ditissima. Further research avenues, including genome sequencing were conducted to enhance understanding and control of a devastating pathogen like N. ditissima. Integrating findings from these studies proposes a comprehensive management strategy incorporating preventive spray programs, alternative fungicides, and pathogen identification to combat these diseases effectively, ensuring sustainable production of apples and pears in orchards. This holistic approach offers growers a multifaceted toolkit to manage diseases effectively, safeguarding apple and pear orchards' productivity and economic viability. / Master of Science in Life Sciences / In the world of growing apples and pears, keeping diseases under control is crucial for keeping orchards thriving and productive. We conducted studies on three endemic and emerging diseases aiming to create a well-rounded approach to managing them. First, we looked into ways to reduce the impact of shoot blight and fire blight cankers on pear trees caused by a devastating bacterium Erwinia amylovora. We tested the efficacy of preventive spray applications of plant extract of giant knotweed alongside antibiotics and found more sustainable alternatives to antibiotics that effectively control this disease. Next, we studied bitter rot disease in apples caused by many different species of fungi in Colletotrichum genus. We determined the efficacy of eighteen different biorational and synthetic fungicide spray programs over two years to find new options that can help prevent fungicide resistance development against currently available fungicides in the market. Several fungicides showed promise in managing this disease including Omega, Aprovia, Ferbam, Captan, Ziram and Cabrio, adding to the effective materials that growers already rely on. Lastly, we investigated the emergence of European canker on cider apple trees. This disease, caused by a fungus Neonectria ditissima, poses a serious threat to cider production. We confirmed the pathogen's identity and its capability of causing the disease in controlled experiments. We propose a comprehensive strategy for managing these diseases by including preventive spray applications of alternative materials and classic fungicides, combined with accurately identifying the pathogens. Our holistic approach provides growers with a range of tools to effectively protect their orchards, ensuring sustainable production of both apples and pears.
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