Submitted by (lucia.rodrigues@ufrpe.br) on 2017-03-20T15:13:40Z No. of bitstreams: 1 Luiz Carlos Cordeiro de Almeida.pdf: 752265 bytes, checksum: 0b51cc544b4a3c3490d349aa5cd97677 (MD5) / Made available in DSpace on 2017-03-20T15:13:40Z (GMT). No. of bitstreams: 1 Luiz Carlos Cordeiro de Almeida.pdf: 752265 bytes, checksum: 0b51cc544b4a3c3490d349aa5cd97677 (MD5) Previous issue date: 2005-02-28 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Anthracnose, caused by Colletotrichum gloeosporioides and Colletotrichum sp., is the most important post harvest disease on the yellow passion fruit. The disease management measures have not been satisfactory ever during the pre or post harvest period. Aiming to contribute to the program of cultivar resistance, 33 isolates were obtained from three producing regions of Pernambuco State, to: i) identify specie with genetic marker (PCR primer); ii) to know the pathogen aggressiveness on post harvested yellow passion fruits; iii) aggressiveness characterization using: biochemical (extra cellular enzymatic activity on specific solid media), physiological (micelial growth on PDA) and genetic (RAPD primer)markers. Also, it was studied anthracnose control on post harvested yellow passion fruit using acibenzolar-S-methyl (ASM), DL -amine-n-butyric acid (BABA) and methyl jasmonate (MJ) chemical inducers. None DNA extracted from isolates reacted with C. gloeosporioides and C. acutatum PCR primers markers, but 18 DNAs reacted with Colletotrichum of Passiflora PCR primermarker, although isolates not identified genetically showed morphological characteristics similar to C. gloeosporioides. Yellow passion fruits inoculations showed two isolate groups for aggressiveness: high (AG-1) and low (AG-2), but aggressiveness did not correlate with origin and teleomorphic and anamorphic morphotype. The biochemical (amilolytic, celullolytic, lypolytic and proteolytic enzymatic activities) and physiological (micelial growth) markers separated isolates in groups, but they were not a satisfactory makers to aggressiveness. It was not detected pectinolytic enzymatic activity by isolates because the used method it was not appropriated. Bands produced by reaction of 33 DNAs with 18 primers showed that AG-1 isolates are more related to each other than AG-2 isolates, being possible to separate isolates in two genetic groups,which not totality related with AG-1 and AG-2 isolates. The reactions of the RAPD OPA-9 primer with isolates DNA produced bands in position 14, on agarose gel, which allowed characterization of the 85.7 % of AG-1 isolates, showing error of 15.7 % by including three isolates from AG-2 into AG-1, but without technique importance. Study with the chemical ASM, BABA e MJ inducers showed that ASM and MJ, at 12.5; 25.0, 50.0 and 100.0 ppm concentrations, and BABA, at 50, 100, 500 and 1000 ppm concentrations, did not reduce Colletotrichum conidia germination, but BABA and JM stimulate this physiological process. ASM and JM reduced mycelium growth and BABA showed contrary effect. Yellow passion fruits immersed in ASM (100ppm), BABA (1000 ppm) and MJ (100 ppm) suspension and water (control), followed by Colletotrichum inoculation 24 hours after treatment, did not show anthracnose control. / A antracnose, causada por Colletotrichum gloeosporioides e Colletotrichum sp. é uma das doenças em pós-colheita mais importantes do maracujazeiro amarelo. Apesar da existência de medidas de manejo tanto para a pré-colheita como para a pós-colheita, o controle não é satisfatório. Visando contribuir com um programa para aumentar a resistência da planta, foram coletados 33 isolados de Colletotrichum, obtidos de três regiões produtoras do estado de Pernambuco, para: i) identificação específica com marcadores genéticos primers de PCR; ii) conhecer agressividades em maracujá amarelo; iii) caracterizá-la com marcador bioquímico, pela produção de enzimas hidrolíticas extra celulares em meios sólidos específicos, fisiológico, pelo crescimento micelial em meio de BDA e genético, com primers de RAPD. Também se estudou o controle da antracnose em maracujá amarelo com uso dos indutores químicosacibenzolar-S-metil (ASM), ácido LD -amino–n–butírico (BABA) e jasmonato metílico (JM). Nenhum DNA dos isolados reagiu com os primers de PCR marcadores para C. gloeosporioides e C. acutatum, mas 18 reagiram com o primer de PCR marcador para Colletotrichum de Passiflora, embora os isolados não identificados geneticamente apresentassem características morfológicas semelhantes às de C. gloeosporioides. Inoculações em maracujá amarelo permitiram separar os isolados em dois grupos de agressividade: alta (GA-1) e baixa (GA-2), embora a agressividade não tenha se correlacionado com a origem e os morfotipos teleomorfo e anamorfo. Os marcadores bioquímico (atividade enzimática amilolítica, celulolítica, lipolítica e proteolítica) e o marcador fisiológico (crescimento micelial) separaram os isolados em grupos, mas não se mostraram satisfatórios como marcadores para agressividade. Nãofoi detectada atividade enzimática pectinolítica devido ao método ter sido inadequado.As bandas geradas pelas reações de 18 primers com os DNAs dos isolados permitiram observar que os isolados do GA-1 são mais próximos geneticamente entre si do que os isolados do GA-2, sendo possível dividi-los em dois grupos genéticos que não se relacionaram totalmente com os isolados do GA-1 e GA-2. O marcador banda na posição 14 em gel de agarose, resultante das reações dos DNAs dos isolados com o primer de RAPD OPA-9, possibilitou a caracterização de 85,7 % dos isolados do GA-1, com um erro de 15,7 % ao caracterizar como do GA-1 três isolados do GA-2, mas sem importância técnica. Os estudos com os indutores ASM, BABA e JM, evidenciaram que ASM e JM, nas concentrações 12,5; 25,0; 50,0; e 100,0 ppm, e BABA, nas concentrações 50; 100; 500; e 1000 ppm, não reduziram a germinação de conídios de Colletotrichum sp., mas BABA e JM estimularam este processo fisiológico. Os indutores ASM e JM reduziram o crescimento micelial e BABA apresentou efeito contrário. A imersão de maracujá amarelo em suspensão de ASM (100 ppm), JM (100 ppm), BABA (1000 ppm) e em água (testemunha) seguida de inoculação feita 24 h após com Colletotrichum sp. não resultou em controle da doença.

Cultivars of Agrostis stolonifera showed weak and strong responsiveness to the systemic acquired resistance (SAR) activator, benzothiadiazole (BTH), or the induced systemic resistance (ISR) activator, 2R, 3R-butanediol (BD). Next Generation RNA sequencing was used to identify 2163 putative transcripts with increased expression in BTH versus water-treated A. stolonifera. Among three BTH-induced genes, AsASP-2 and AsHIR-1 were induced faster, while AsLOX-1 had stronger transient induction, in one out of two strongly BTH-responsive cultivars. Three ISR-responsive genes, AsGNS-5, AsOPR-4 and AsAOS-1, showed no greater induction or priming in the strongly versus weakly BD-responsive cultivars. Cultivars of A. stolonifera vary significantly in their response to defense activators, however this is not consistently related to defense gene expression. To quantify disease severity, chlorophyll fluorescence imaging of the maximum quantum efficiency of photosystem II (Fv/Fm) was tested on Nicotiana benthamiana infected with Colletotrichum orbiculare. Leaf areas of healthy, non-necrotic affected and necrotic tissue could be individually quantified, which demonstrated that BD delayed symptom development by approx. 24-hour and reduced non-necrotic affected tissue compared to controls. Chlorophyll fluorescence imaging can quantify and reveal novel features about induced disease resistance.

Avocados are one of the major food sources in tropical and subtropical regions and are an important horticultural crop in South Africa. Avocados are exported over long distances and may have storage times of up to 30 or more days at temperatures of about 5.5oC. This procedure increases the risk of poor fruit quality, including physiological disorders, early softening and postharvest disease incidence. A major component of the postharvest diseases is Anthracnose caused by Colletotrichum gloeosporioides. Anthracnose infects unripe fruit and once infected, the fungus remains dormant in the fruit until ripening begins. This leads to a problem for producers and packers, as the presence of the disease cannot be detected on the pack line, and fruit is not removed. Anthracnose control is normally done through pre-harvest treatment with copper-based fungicides. While effective such treatment needs to be repeated frequently, resulting in copper residues on the avocados. The study was conducted to investigate the effects of phosphoric acid and potassium silicate on known antifungal compounds and critical enzymes of the pathways elemental for systemic resistance inducers, so as to evaluate the potential for using them as alternatives to or in conjunction with, copper fungicides in the control of Anthracnose in avocado fruit. The study included storage temperature and time variations, to take account of the logistics in shipping avocado fruit to distant markets. Pre- and postharvest applications of phosphoric acid and potassium silicate were used, and after harvest, fruit were either ripened at room temperature (22oC) without storage or stored for 28 days at temperatures of 5.5oC or 2oC before analysis. Concentrations of phenolics, activity of the enzyme phenylalanine ammonia lyase (PAL) and a known antifungal diene were determined in the fruit exocarp. Pre-harvest treatments of phosphoric acid showed that the highest phenolic concentration was found in fruit harvested 14 days after application for fruit stored at room temperature. For fruit stored at 5.5°C it was seen that as fruit softened, phenolic concentrations increased compared with hard fruit immediately after storage, with the highest increase noted for fruit harvested 7 days after application. When comparing the three storage temperatures, phenolic concentrations were enhanced most when fruit was stored at 2°C. Postharvest treatments showed a significant increase in phenolic concentrations for potassium silicate treated fruit stored at room temperature and 2°C when determined immediately after storage. Fruit stored at 5.5°C showed an increase in phenolic concentrations as it became softer. When considering PAL enzyme activity, it was found that postharvest treatments of both potassium silicate and phosphoric acid influenced enzyme activity, with potassium silicate having greater effects. Similarly, an increase in PAL activity was noted in the pre-harvest phosphoric acid treatment harvested 14 days after application for fruit ripened immediately as well as fruit stored at 5.5°C. Fruit stored at 2°C showed the highest PAL activity for fruit harvested 7 days after application. No results were obtained in the analysis of antifungal compounds for both pre- and postharvest treatments. However, it is suggested that the antifungal diene could follow similar trends to those found for phenolics. It is concluded that applications of both phosphoric acid and potassium silicate do create changes in phenolic concentrations and the activity of the enzyme PAL which is involved in the synthesis of phenolic compounds known to possess antifungal properties. It is therefore possible that phosphoric acid and potassium silicate may be used as part of an integrated programme for Anthracnose control, and should be tested as potential alternatives for high volume copper-based fungicides. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.

Submitted by (lucia.rodrigues@ufrpe.br) on 2017-03-27T16:34:00Z No. of bitstreams: 1 Wagner Rogerio Leocadio Soares Pessoa.pdf: 794895 bytes, checksum: fa791ef69e88320cf4072254f9211112 (MD5) / Made available in DSpace on 2017-03-27T16:34:00Z (GMT). No. of bitstreams: 1 Wagner Rogerio Leocadio Soares Pessoa.pdf: 794895 bytes, checksum: fa791ef69e88320cf4072254f9211112 (MD5) Previous issue date: 2009-03-13 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The banana is the second fruit more consumed in the world, being the fruit fresh holder of larger world market. Brazil, answers as second producing adult, using the varieties Silver and Pacovan in approximately 60% of area harvestd. However, several factors can cause losses in the production. In the powder-crop to the anthracnose, caused by Colletotrichum musae, it is the main and more destructive, harming the commercialization. Before that, the present work concerns the evaluations of alternative methods of control that seek to the reduction of the losses powder-crop in bananas caused by the C. musae. The first work is had the effect of resistance inductors in the control powder-crop of the anthracnose in banana.Among the tested inductors they are had the Acibenzolar-S-methyl (ASM), Agriculture-Mós®, Ecolife®, Crop-Set®, methyl jasmonate, were applied in the dosage recommended by the manufacturer (DR) and DR added of 50% there is plus, for five minutes of immersion, the inoculations were accomplished under the times of zero, six and 12 hours after the induction. In the second rehearsal the production of the enzymes was evaluated: peroxidase, polifenoloxidase, quitinase, β-1,3-glucanase and β -1,4-glucanase under bananas induce with biotic elicitores and abióticos. The third experiment, concerns the thermotherapy (TH) associate to ASM in the control of the anthracnose. Where bouquets were treated by immersion in warm water to 40, 45, 50 and 55 ± 1 ºC, for the times of zero, five, 10 and 15 minutes, parallel to these treatments the bouquets were immersed in syrup containing ASM, for five minutes, in the DR for the manufacturer. In relation to the fourth work, the effect of dosages zero 50, 150, 300 and 450 nL.L-1 of 1-MCP on the banana anthracnose was verified. The inoculations of all of the works were accomplished with a suspension of conidial of C. musae in the concentration 106 con./mL, deposited on the epidermis previously wounded. At the end of each rehearsal they were appraised the banana's physiochemical characteristics except for the second. ASMapplied 12 hours before the inoculation in the added of 50% commercial dosage there is plus, it was the most efficient in the control of the disease. In relationship, to enzymes peroxidase, polifenoloxidase β -1,3-glucanase and β -1,4-glucanase, AGM and MJ the most efficient inductors were in the production of these enzymes, in relation to the quitinase AGM did just stand out in relation to the others. To the temperatures around of 40 and 45 ºC in all of the times of exhibition tested were the most expressive in the reduction of the severity in relationship á testifies. In TH + ASM, for the temperatures from 45 to 50 °C in all of the times of exhibition and 40 °C in the times of 10 and 15 minutes presented smaller severity of the disease in relation to isolated TH. In the 1-MCP, the dosages of 150 and 50 nL.L-1 they presented the smallest severity values with 9,57 and 9,67 mm, respectively, following for the dosage of 300 and 450 nL.L-1 with 10,18 to 10,5 mm. The witness presented the largest severity with 32,04 mm being reduced in the progressive largest way for to smallest dosage.It didn't happen significant changes in the pH, SST and ATT, that commit the commercialization and the banana's consumption in natura. / A banana (Musa spp.)é a segunda fruta mais consumida no mundo, sendo a fruta fresca detentora de maior mercado mundial. O Brasil, responde como segundo maior produtor, utilizando as cvs. Prata e Pacovan em aproximadamente 60 % de sua área cultivada. Contudo, diversos fatores podem ocasionar perdas na produção. Na pós-colheita à antracnose, causada por Colletotrichum musae, é a principal e mais destrutiva, prejudicando a comercialização. Diante disso, o presente trabalho tem por objetivo avaliar métodos alternativos de controle que visem à redução das perdas pós-colheita em bananas causada por C. musae. O primeiro artigo tem-se o efeito de indutores de resistência no controle pós-colheita da antracnose em banana. Foram avaliados os indutores acibenzlar-S-metil (ASM), Agro-Mós®, Ecolife®, Crop- Set®, metil jasmonato, sendo aplicado na dosagem recomendada (DR) pelo fabricante e DR acrescido de 50 %, por cinco minutos de imersão. As inoculações com o isolado Cm 10 foram realizadas sob os tempos de zero, seis e 12 horas após a indução. No segundo artigo, avaliou-se a produção das enzimas peroxidase, polifenoloxidase, quitinase, β-1,3-glucanase e β-1,4- glucanase sob bananas induzidas com elicitores bióticos e abióticos. O terceiro artigo, diz respeito ao tratamento hidrotérmico (TH) associado ao ASM no controle da antracnose. Onde buquês foram tratados por imersão em água aquecida a 40, 45, 50 e 55 ± 1 ºC, pelos tempos de zero, cinco, 10 e 15 minutos. Paralelo ao tratamento TH, os buquês foram imersos em calda contendo o ASM, por cinco minutos, na DR do fabricante. Em relação ao quarto artigo, verificou-se o efeito de dosagens 0, 50, 150, 300 e 450 nL.L-1 de 1-MCP sobre a antracnose da banana. As inoculações de todos os trabalhos foram realizadas com suspensão de conídios de C. musae na concentração de 106 con./mL, depositado sobre a epiderme previamente ferida. Ao final de cada ensaio foram avaliadas as características físico-químicas da banana com exceção do segundo experimento. O ASM e o AGM aplicado 12 horas antes dainoculação na dosagem comercial acrescido de 50 %, foram o mais eficientes no controle da doença. Em relação as enzimas peroxidase, polifenoloxidase, β-1,3-glucanase e β-1,4- glucanase, o AGM e o MJ foram os indutores mais eficientes em sua produção. Para a quitinase apenas o AGM destacou-se em relação aos demais. Às temperaturas ao redor de 40 a 45 ºC em todos os tempos de exposição testados foram as mais expressivas na redução da severidade da doença em relação á testemunha. No TH + ASM, para as temperaturas de 45 a 50 °C em todos os tempos de exposição e 40 °C nos tempos de 10 e 15 minutos apresentaram menor severidade da doença em relação ao TH isolado. No 1-MCP as dosagens de 150 e 50 nL.L-1 apresentaram os menores valores de severidade com 9,57 e 9,67 mm, respectivamente. Não ocorreram mudanças significativas no pH, SST e ATT, que comprometessem a comercialização e o consumo in natura da banana.

Na indução de resistência a planta possui mecanismos de defesa físicos e químicos para impedir a entrada e o desenvolvimento de patógenos e parasitas, incluindo fungos, bactérias, vírus, nematóides e até insetos. Estes mecanismos são ativados por infecções prévias ou pelo tratamento com agentes indutores (eliciadores) bióticos ou abióticos. Entre os agentes indutores bióticos, destaca-se a S. cerevisiae, que além da importância biotecnológica, tem demonstrado em estudos prévios potencial para o controle de doenças em várias plantas de importância econômica. Produtos à base de S. cerevisiae, como por exemplo o Agro-Mos® (carboidratos da parede celular da levedura) estão disponíveis no mercado, mas não como indutores de resistência. Já o indutor químico registrado como Bion® vem sendo comercializado e utilizado na indução de resistência em diversas espécies de plantas contra vários patógenos. Os objetivos deste trabalho foram purificar parcialmente frações de S. cerevisiae indutoras de resistência em pepineiro contra antracnose, causada por Colletotrichum lagenarium, e avaliar o efeito do extrato bruto autoclavado de S. cerevisiae, Agro-Mos® e Bion® na indução de resistência contra o inseto T. absoluta em tomateiro, o nematóide M. incognita em pepineiro, como também, verificar o efeito destes agentes na interação simbiótica entre soja e B. elkanii. Os resultados mostraram que o extrato bruto aquoso de S. cerevisiae autoclavado por 4 h foi o mais efetivo na redução da antracnose. Dessa maneira, o mesmo foi submetido à precipitação etanólica e o sobrenadante da precipitação foi fracionado utilizando-se Cromatografia de Troca Aniônica - CTA. Obtiveram-se quatro picos, sendo que os picos I (frações não ligada à resina DEAE-celulose) e II (frações ligadas à resina DEAE-celulose) foram os mais efetivos na proteção de plântulas de pepineiro reduzindo a severidade de antracnose em 80% e 72%, respectivamente. A aplicação foliar do extrato bruto aquoso de S. cerevisiae, Agro-Mos® e Bion® não afetou o desenvolvimento do inseto em tomateiro, como também, não interferiu significativamente na multiplicação do nematóide em raízes de pepineiro. Na interação simbiótica da soja com B. elkanii, os agentes testados não afetaram a nodulação por B. elkanii em raízes e o desenvolvimento vegetativo das plantas. Porém, a aplicação foliar do extrato bruto autoclavado de S. cerevisiae aumentou a quantidade de nitrogênio total da parte aérea das plantas. Finalmente, conclui-se que frações de S. cerevisiae induziram resistência em pepineiro contra C. lagenarium. Por sua vez, os agentes testados são foram eficientes no controle do inseto herbívoro e do nematóide e não demonstraram efeito negativo na interação soja - rizóbio. / In the resistance induction, the plant has physical and chemical defense mechanisms to avoid the entrance and the development of pathogens and parasites, including fungi, bacteria, virus, nematodes and even insects. These mechanisms are activated by previous infections or by the treatment with biotic and abiotic inducer agents. Among the biotic agents there is S. cerevisiae, that besides the biotechnological importance, was shown in previous studies to control diseases in several plants of economical importance. Products made of S. cerevisiae, as for exemple, the Agro-Mos® (formulated with carbohydrates from the cellular wall of the yeast) are available in the market, but not resistance inducers. The chemical inducer known as Bion® is already marketed and used to induced resistance in several plant species against several pathogens. The objectives of this work were to partially purify fractions of S. cerevisiae able to induce resistance in cucumber against anthracnose, caused by Colletotrichum lagenarium, and also evaluate the effect of the autoclaved crude aqueous extract from S. cerevisiae, Agro-Mos® and Bion® in the resistance induction against the insect T. absoluta in tomato plants, the nematode M. incognita in cucumber plants, as well as to verify the effect of the agents in the symbiotic interaction envolving soybean and B. elkanii. The results showed that the crude aqueous extract of S. cerevisiae autoclaved for 4 h was the most effective out in the reduction of cucumber anthracnose. Thus, the same extract was submitted to ethanolic precipitation and the obtained supernatant was fractioned by using Anion Exchange Chromatography - AEC. For peaks were obtained and peak I (non-adsorbed fraction to DEAE-Cellulose) and II (fraction adsorbed to DEAE-Cellulose) were the most effective out in the protection of the cucumber seedling by reducing anthracnose severity in 81% and 72% ,respectively. The application of the autoclaved extract of S. cerevisiae, Agro-Mos® and Bion® did not affect the development of the insect in tomato plants as well as did not interfere significantly in the multiplication of the nematode in cucumber roots. In the symbiotic interaction of soybean and B. elkanii, the tested agents did not affect the formation of nodules in soybean roots and the vegetative development of the plants. However, the foliar application of the autoclaved crude extract of S. cerevisiae significantly increased the amount of total nitrogen in the aerial part of the plants. Finally, it is concluded that the fractions (peaks I and II) of S. cerevisiae induced resistance of the cucumber plants. However the tested agents were not efficient in the control of the herbivore insect and the nematode and did not exhibit negative effects in the symbiotic interaction soybean and rhizobium.

The common bean (Phaseolus vulgaris L.) is an important crop grown widely in Uganda. It is also an important source of income for smallholder farmers particularly women. Despite its importance, production in the cool highland regions is constrained by anthracnose disease which causes losses in both the quantity and the quality of beans produced. The principal aim of this research was to elucidate on the status of dry bean anthracnose and the genetics governing its resistance. A participatory rural appraisal study was conducted to explore farmers' knowledge, experience, problems and cultivar preferences in association with managing dry bean anthracnose disease. This study revealed that anthracnose is an important constraint to production which is not controlled in any way. Although farmers have varying cultivar preferences, they use mostly home saved seed and only 1% could access improved seed. The study suggested the need for practical approaches in the provision of quality anthracnose resistant seed in consideration of farmers' preferences and the dynamics of their rural livelihoods. A study was conducted to determine the variability of the anthracnose (Colletotrichum lindemuthianum) pathogen in some of the major bean growing regions of Uganda. Use was made of a set of 12 internationally accepted anthracnose differential cultivars to identify the physiological races present. The results obtained indicated the presence of eight races with one race (767) being dominant and most aggressive. Differential cultivars AB 136 and G2333 were resistant to all the eight races, and can be utilised as potential sources of resistant genes. A germplasm collection of mostly Ugandan accessions was screened for anthracnose resistance. Using the area under disease progression curve as the tool for assessing disease severity, eleven accessions were identified that posses good levels of anthracnose resistance. The yield loss attributed to the anthracnose disease was determined on three susceptible Ugandan market-class dry bean cultivars and two resistant cultivars. The results showed that the yield of susceptible cultivars was reduced by about 40% and an almost equivalent yield was lost due to poor quality seed. In comparison, the yield lost by the resistant cultivars was not significant. The study suggested the use of resistant cultivars as the best solution in combating anthracnose resistance. Three susceptible Ugandan market class dry bean cultivars and six resistant cultivars were used for the study of the inheritance of resistance to the anthracnose pathotype 767 in a complete 9x9 diallel design. The results clearly indicated that the resistance was predominately conditioned by additive gene action. It was also established that epistatic gene action was important. More than one pair of genes displaying partial dominance were responsible for determining resistance and the maternal effect did not have an influence on resistance. Additionally, the result showed that some of susceptible cultivars combined very well with the resistant cultivars and that anthracnose resistance heritability estimates in both the narrow and broad sense were high. These results suggested that the use of simple pedigree breeding procedures such as backcross selection could be useful in improving anthracnose resistance levels in the Ugandan market class varieties. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.

Submitted by Marco Antônio de Ramos Chagas (mchagas@ufv.br) on 2017-06-02T17:41:45Z No. of bitstreams: 1 texto completo.pdf: 461198 bytes, checksum: 1983c9ff254d751fb9f67e35fbabb1fc (MD5) / Made available in DSpace on 2017-06-02T17:41:45Z (GMT). No. of bitstreams: 1 texto completo.pdf: 461198 bytes, checksum: 1983c9ff254d751fb9f67e35fbabb1fc (MD5) Previous issue date: 2004-08-03 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Visando piramidar genes de resistência à ferrugem (Uromyces appendiculatus), antracnose (Colletotrichum lindemuthianum) e mancha-angular (Phaeoisariopsis griseola) em cultivar de feijão do tipo carioca, foram intercruzadas quatro isolinhas de feijoeiro-comum. As isolinhas foram obtidas por meio de retrocruzamento nos quais foi utilizado o cv. Rudá como genitor recorrente. As isolinhas continham os seguintes genes de resistência: linha ON-48-99 - genes Co-10 e Ur-ON provenientes do cultivar Ouro Negro, linha AB-74-1-18 - gene Co-6 proveniente do cultivar AB-136, linha TO- 41-5-6-24 - gene Co-4 proveniente do cultivar TO e linha AND-7-2-9-7-10 - gene Phg- 1 proveniente do cultivar AND 277. Após seleção para homozigose e avaliação das características altura de plantas, número de dias para floração, número de dias para maturação, produtividade de grãos, peso de 100 sementes, número de sementes por vagens, número de vagens por plantas, e da reação de resistência aos patótipos de Uromyces appendiculatus, Colletotrichum lindemuthianum e Phaeoisariopsis griseola, as isolinhas foram intercruzadas duas a duas. Em seguida, as plantas F 1 foram intercruzadas para obter os híbridos duplos. Os marcadores moleculares SCAR-F10 1150a , SCAR-BA8 560a , OPX11 550a , OPY20 830a , OPB03 1800r , OPAZ20 940a e OPH13 490a associados aos respectivos genes de resistência Ur-ON, Co-10, Co-6, Co-4 e Phg-1 proveniente foram utilizados para identificar as plantas contendo todos os genes de interesse as quais foram autofecundadas para obtenção de sementes F 2 . As sementes F 2 foram semeada em casa de vegetação, e as plantas F 2 foram genotipadas utilizando-se de marcadores moleculares ligados aos genes de resistência. A resistência das plantas foi também confirmada por inoculação dos patógenos. Na geração F 3 foi feita nova avaliação com os marcadores moleculares, selecionando-se apenas as plantas que apresentavam todas as marcas. Este procedimento foi também utilizado na geração F 4 . No final deste processo foi obtida uma população constituída de 40 famílias F 4 denominadas genericamente por ́Rudá R`. Paralelamente, foi feito o cruzamento de ́Rudá R` com o cv. Pérola, obtendo-se 30 famílias F 4 . Sementes das famílias F 4:5 foram multiplicadas para realização de experimento a campo. As famílias F 4:6 foram testadas quanto ao seu desempenho agronômico em ensaio em condição de campo e foram selecionadas 4 e 3 linhagens F 4:7 de cada população, respectivamente. Estas famílias foram avaliadas quanto à resistência a diferentes patótipos de U. appendiculatus, C. lindemuthianum e P. griseola. As inoculações feitas em famílias F 4:7 mostraram que as famílias R-127-10-14, R-97-13-5, R-97-13-6, R-127-4-13, P-33-5-1, P-49-8-2 e P-49-2- 2 se comportaram como resistentes a todos os patótipos de U. appendiculatus e C. lindemuthianum, e a cinco dos sete patótipos de P. griseola inoculados. As melhores familias serão avaliadas em uma rede de ensaio de Valor de Cultivo e Uso (VCU) para uma possível recomendação de um novo cultivar de feijão tipo carioca. A seleção de linhagens de feijão com grãos do tipo carioca, resistentes à ferrugem, antracnose e mancha-angular confirmam o grande potencial e a importância do uso da seleção assistida por marcadores moleculares em programas de piramidação de genes de resistência. / The objective of this work was to pyramid resistance genes to rust (Uromyces appendiculatus), anthracnose (Colletotrichum lindemuthianum) and angular leaf spot (Phaeoisariopsis griseola) in the "carioca-type" common bean cultivar Rudá. Four isolines were obtained in four backcross programs and intercrossed. The isolines contained the following resistance genes: isoline ON-48-99 - genes Co-10 and Ur-ON from cultivar Ouro Negro (ON), isoline AB-74-1-18 - gene Co-6 from cultivar AB 136, isoline TO-41-5-6-24 - gene Co-4 from cultivar TO and isoline AND-7-2-9-7-10 - gene Phg-1 from cultivar AND 277. After selection for homozygosis and evaluation of different quantitative, morphologic, and molecular characteristics, and for resistance to rust, anthracnose and angular leaf spot, the isolines were intercrossed. The F 1 plants were intercrossed to obtain the double hybrid. The molecular markers SCAR-F10 1150a , SCAR-BA8 560a , OPY20 830a , OPAZ20 940a , OPH13 490a , OPX11 550a and OPB03 1800r associated to the resistance genes were used to identify the plants containing all the genes of interest which were selfed to obtain the F 2 seeds. The F 2 seeds were sown, and the corresponding plants were selected with molecular markers linked to the resistance genes and resistance was confirmed by inoculation of the pathogens. The selection based on molecular markers was repeated in the F 3 and F 4 generations, only plants containing all the markers were selected. At the end of this process a population of 40 families was obtained and designated ́Rudá R`. In a parallel procedure, ́Rudá R` were crossed with cv. Pérola. Thirty F 4 families ( ́Rudá R` x Pérola) were obtained. Seeds of the F 4:5 families were multiplied and used for agronomic evaluation in preliminary field tests. Four and three lines were selected from populations ́Rudá R` and ́Rudá R` x Pérola, respectively. These lines were tested against different pathotypes of U. appendiculatus, C. lindemuthianum and P. griseola. The inoculations done in F 4:7 lines showed that the lines R-127-10-14, R-97-13-5, R-97-13-6, R-127-4-13, P-33-5-1, P-49- 8-2 and P-49-2-2 were resistant to all pathotypes of U. appendiculatus and C. lindemuthianum, and to five of the seven pathotypes of P. griseola tested. The lines are xstill being analyzed for quantitative characteristics in field trials. The best lines will be tested in an official trial to be released as new varieties of "carioca-type" bean. The selection of bean lines with "carioca-type" grains, resistant to rust, anthracnose and angular leaf spot confirm the power and importance of the use of marker assisted selection in breeding programs aiming to pyramid disease resistance genes.

No description available.

Na indução de resistência a planta possui mecanismos de defesa físicos e químicos para impedir a entrada e o desenvolvimento de patógenos e parasitas, incluindo fungos, bactérias, vírus, nematóides e até insetos. Estes mecanismos são ativados por infecções prévias ou pelo tratamento com agentes indutores (eliciadores) bióticos ou abióticos. Entre os agentes indutores bióticos, destaca-se a S. cerevisiae, que além da importância biotecnológica, tem demonstrado em estudos prévios potencial para o controle de doenças em várias plantas de importância econômica. Produtos à base de S. cerevisiae, como por exemplo o Agro-Mos® (carboidratos da parede celular da levedura) estão disponíveis no mercado, mas não como indutores de resistência. Já o indutor químico registrado como Bion® vem sendo comercializado e utilizado na indução de resistência em diversas espécies de plantas contra vários patógenos. Os objetivos deste trabalho foram purificar parcialmente frações de S. cerevisiae indutoras de resistência em pepineiro contra antracnose, causada por Colletotrichum lagenarium, e avaliar o efeito do extrato bruto autoclavado de S. cerevisiae, Agro-Mos® e Bion® na indução de resistência contra o inseto T. absoluta em tomateiro, o nematóide M. incognita em pepineiro, como também, verificar o efeito destes agentes na interação simbiótica entre soja e B. elkanii. Os resultados mostraram que o extrato bruto aquoso de S. cerevisiae autoclavado por 4 h foi o mais efetivo na redução da antracnose. Dessa maneira, o mesmo foi submetido à precipitação etanólica e o sobrenadante da precipitação foi fracionado utilizando-se Cromatografia de Troca Aniônica - CTA. Obtiveram-se quatro picos, sendo que os picos I (frações não ligada à resina DEAE-celulose) e II (frações ligadas à resina DEAE-celulose) foram os mais efetivos na proteção de plântulas de pepineiro reduzindo a severidade de antracnose em 80% e 72%, respectivamente. A aplicação foliar do extrato bruto aquoso de S. cerevisiae, Agro-Mos® e Bion® não afetou o desenvolvimento do inseto em tomateiro, como também, não interferiu significativamente na multiplicação do nematóide em raízes de pepineiro. Na interação simbiótica da soja com B. elkanii, os agentes testados não afetaram a nodulação por B. elkanii em raízes e o desenvolvimento vegetativo das plantas. Porém, a aplicação foliar do extrato bruto autoclavado de S. cerevisiae aumentou a quantidade de nitrogênio total da parte aérea das plantas. Finalmente, conclui-se que frações de S. cerevisiae induziram resistência em pepineiro contra C. lagenarium. Por sua vez, os agentes testados são foram eficientes no controle do inseto herbívoro e do nematóide e não demonstraram efeito negativo na interação soja - rizóbio. / In the resistance induction, the plant has physical and chemical defense mechanisms to avoid the entrance and the development of pathogens and parasites, including fungi, bacteria, virus, nematodes and even insects. These mechanisms are activated by previous infections or by the treatment with biotic and abiotic inducer agents. Among the biotic agents there is S. cerevisiae, that besides the biotechnological importance, was shown in previous studies to control diseases in several plants of economical importance. Products made of S. cerevisiae, as for exemple, the Agro-Mos® (formulated with carbohydrates from the cellular wall of the yeast) are available in the market, but not resistance inducers. The chemical inducer known as Bion® is already marketed and used to induced resistance in several plant species against several pathogens. The objectives of this work were to partially purify fractions of S. cerevisiae able to induce resistance in cucumber against anthracnose, caused by Colletotrichum lagenarium, and also evaluate the effect of the autoclaved crude aqueous extract from S. cerevisiae, Agro-Mos® and Bion® in the resistance induction against the insect T. absoluta in tomato plants, the nematode M. incognita in cucumber plants, as well as to verify the effect of the agents in the symbiotic interaction envolving soybean and B. elkanii. The results showed that the crude aqueous extract of S. cerevisiae autoclaved for 4 h was the most effective out in the reduction of cucumber anthracnose. Thus, the same extract was submitted to ethanolic precipitation and the obtained supernatant was fractioned by using Anion Exchange Chromatography - AEC. For peaks were obtained and peak I (non-adsorbed fraction to DEAE-Cellulose) and II (fraction adsorbed to DEAE-Cellulose) were the most effective out in the protection of the cucumber seedling by reducing anthracnose severity in 81% and 72% ,respectively. The application of the autoclaved extract of S. cerevisiae, Agro-Mos® and Bion® did not affect the development of the insect in tomato plants as well as did not interfere significantly in the multiplication of the nematode in cucumber roots. In the symbiotic interaction of soybean and B. elkanii, the tested agents did not affect the formation of nodules in soybean roots and the vegetative development of the plants. However, the foliar application of the autoclaved crude extract of S. cerevisiae significantly increased the amount of total nitrogen in the aerial part of the plants. Finally, it is concluded that the fractions (peaks I and II) of S. cerevisiae induced resistance of the cucumber plants. However the tested agents were not efficient in the control of the herbivore insect and the nematode and did not exhibit negative effects in the symbiotic interaction soybean and rhizobium.