A ferrugem asiática da soja é a principal doença da cultura, atacando principalmente no período reprodutivo, ocasionando a queda prematura das folhas, redução do ciclo e consequentemente queda na produtividade. As principais abordagens utilizadas para o controle desta doença são a resistência genética e a aplicação preventiva de fungicidas, porém, estas atuam selecionando patógenos mais adaptados, podendo ocasionar a quebra da resistência genética ou a insensibilidade ao fungicida. Portanto, a identificação e utilização de genótipos tolerantes é justificada, uma vez que com esta estratégia pode-se minimizar a pressão de seleção sobre o patógeno. A abordagem univariada é usualmente empregada no estudo de populações segregantes, mas esta pode não ser suficiente na identificação e seleção de genótipos com potencial para tolerância à ferrugem. Esta pesquisa propõe utilizar tanto as informações obtidas na parcela, quanto a correlação entre elas para auxiliar na escolha dos caracteres a serem utilizados na seleção indireta e para a estimação das capacidades gerais e específicas de combinação multivariada. Para alcançar os objetivos, foram utilizadas análises dialélicas uni e multivariada, índices de seleção à tolerância a estresse, análise de componentes principais, agrupamento, correlações e análises de trilha. Foram avaliados 40 cruzamentos oriundos de um dialelo parcial 4x10, na geração F2, em dois manejos de fungicidas (com e sem controle da ferrugem). Os cruzamentos foram avaliados em experimentos delineados em blocos ao acaso, com quatro repetições organizadas em conjuntos experimentais com testemunhas comuns; experimentos com os genitores foram delineados em blocos ao acaso com três repetições e as mesmas testemunhas comuns. Verificou-se que os genitores apresentaram base genética relativamente ampla com comportamento favorável à tolerância à ferrugem e os cruzamentos apresentaram potencial produtivo similar à média nacional, mesmo em contato com a doença. O uso de notas de valor agronômico identificou os cruzamentos mais produtivos dentro de cada manejo, sendo um valioso caráter para exclusão precoce de cruzamentos de baixo desempenho. A utilização de índices de seleção para tolerância a estresses proporcionou a identificação de cruzamentos tolerantes e adaptados às condições de manejo com e sem controle da ferrugem. Para produtividade de grãos, em ambos os ambientes de fungicidas, os maiores destaques ocorreram nos genitores V Max RR, USP 14-22.010, USP 14-22.003 e USP 14-22.008; e nos cruzamentos V Max RR x USP 14-22.009, V Max RR x USP 14-22.010 e BMX Potência RR x USP 14-22.003. A análise dialélica multivariada utilizando ideótipos permitiu a identificação dos genitores e cruzamentos mais promissores para determinados grupos de características. O genitor V Max RR proporcionou maiores efeitos aditivos para as características reprodutivas e a linhagem genitora USP 14-22.010 para as adaptativas, nos dois manejos de fungicidas. O cruzamento MSOY 7908 RR x USP 14-22.001 destacou-se para as características adaptativas e reprodutivas no manejo com controle da ferrugem. Assim, a abordagem multivariada mostrou-se promissora para a seleção de genótipos tolerantes à ferrugem da soja. / Asian soybean rust is a major disease of soybean, damaging the crop mainly during the reproductive period, causing premature fall of the leaves, reduction of the cycle and consequently decrease in productivity. The main methods used for the control of this disease are genetic resistance and the use of preventive fungicides, but these act by selecting more adapted pathogens, resulting in the breakdown of genetic resistance or insensitivity to the fungicide. Therefore, the identification and use of tolerant genotypes is justified, since there is no selection pressure on the pathogen. The univariate approach is usually employed in the study of segregating populations, but may not be sufficient in identifying and selecting genotypes with potential for rust tolerance. Thus, the present work proposes to use both the information obtained in the plot and the correlation between them to assist in the selection of the traits to be used in the indirect selection and for the estimation of the general and specific capacities of the multivariate combination. In order to reach the objectives, uni and multivariate diallel analyses, stress tolerance indices, principal components analysis, clustering, correlation and path analysis were used. There were evaluated 40 crosses from a partial diallel 4x10, in the F2 generation, in two experiments with fungicide treatments (with and without rust control) in randomized blocks design stratified in sets, with four replications; the parents were evaluated in other two experiments in randomized blocks design with three replications. It was verified that the parents presented a relatively broad genetic base with favorable tolerance to rust, and the crosses presented good productive potential, even in contact with the disease. The use of agronomic value was able to identify productive crosses within each management. The use of selection indices for stress tolerance allowed the identification of tolerant crosses and adapted to the conditions of management with and without rust control. For seed yield, in both fungicide environments, the most prominent parents were V Max RR, USP 14-22.010, USP 14-22.003 and USP 14-22.008; and the crosses were V Max RR x USP 14-22.009; V Max RR x USP 14-22.010 and BMX Potência RR x USP 14-22.003. Multivariate diallel analysis using ideotypes allowed the identification of the most promising parents and crosses for certain groups of traits. The genitor V Max RR provided greater additive effects for the reproductive traits and the experimental line USP 14-22.010 for the adaptive ones in both fungicide management. The crossing MSOY 7908 RR x USP 14-22.001 was prominent for the adaptive and reproductive characteristics in the management 1 (with rust control). Thus, the multivariate approach was promising for the selection of soybean rust tolerant crosses.

Essa pesquisa buscou comparar as tecnologias transgênica (soja RR e manejo com glifosato) e convencional (soja e manejo convencionais) quanto à maior tolerância à ferrugem asiática (Phakopsora pachyrhizi) e obtenção de genótipos promissores para produtividade de grãos (PG) e tamanho das sementes (representado pelo peso de cem sementes, PCS). Foram avaliadas 200 progênies F2:5 e F2:6 oriundas de dois dialelos parciais 5 x 2, ambos com cinco genitores de alta produtividade de óleo (USP 70.108, USP 70.010, USP 70.113, USP 70.007 e USP 70.042) em cruzamentos com: (1) duas cultivares elites convencionais (BRS 133 e Conquista); (2) suas versões essencialmente derivadas transgênicas (BRS 245 RR e BRS Valiosa RR). Os experimentos envolveram: a) dois manejos com herbicidas, manejo convencional para soja convencional e manejo com glifosato para a soja RR; b) dois manejos de fungicidas, sendo um experimento com aplicações sucessivas de Opera & Nativo (O&N, para controle da ferrugem e das doenças de final de ciclo, DFC) e outro experimento com aplicações de Derosal para controle apenas das DFC. O efeito da ferrugem para cada genótipo foi expresso pela taxa de reação da ferrugem sobre a produtividade (FP) e o tamanho das sementes (FT), calculados pelas diferenças entre médias ajustadas de PG e PCS nos dois experimentos com fungicidas. As comparações foram feitas em análises de variância, testes de médias e de parâmetros de capacidade de combinação. O controle da ferrugem com fungicidas (O&N) resultou em maiores médias de PG e PCS. Houve grande variação entre os efeitos de capacidades geral e específica, com destaque dos genitores USP 70.108, USP 70.010 e BRS 133 para PG e FP. O genitor mais divergente e com dominância positiva para PG foi USP 70.042. As duas tecnologias foram numericamente semelhantes para tolerância à ferrugem (FP e FT). A tecnologia convencional apresentou a vantagem de ser estatisticamente mais produtiva (PG e PCS) do que a tecnologia transgênica. Por outro lado, a tecnologia transgênica tem a vantagem de ter uso mais fácil e menor custo de cultivo aos produtores. / This research aimed to compare the performance of transgenic (RR soybean and management with glyphosate) and conventional (conventional soybean and herbicides) technologies for tolerance to rust (Phakopsora pachyrhizi ) and obtaining promising genotypes for seed yield and size (represented by the weight of one hundred seeds, PCS). A total of 200 progenies were evaluated in F2:5 and F2:6 generations; these progenies were obtained in two partial diallel 5 x 2, both involving five parents with high oil yield (USP 70.108, USP 70.010, USP 70.113, USP 70.007 and USP 70.042) in crosses with: (1) two elites conventional cultivars (BRS 133 and Conquista); (2) their essentially derived transgenic versions (BRS 245 RR and BRS Valiosa RR). The experiments involved: a) two managements with herbicides: conventional management for conventional soybean and management based in glyphosate herbicide to RR soybean; b) two managements with fungicides: an experiment with successive applications of Opera & Native (O&N, fungicides that control rust and late season leaf diseases, DFC), and another experiment with Derosal applications (fungicide that controls only DFC). The effect of rust for each genotype was expressed by the rate of reaction to rust on seed yield (FP) and on seed size (FT) as calculated from the differences in seed yield (PG) and seed size (PCS) between adjusted means in the two experiments with different fungicides. The soybean genotypes were compared by analysis of variance, multiple comparisons and parameter estimation of combining ability. In general, the control of rust with fungicides (O&N) resulted in higher means of PG and PCS. There was great variation among the effects of general and specific combining abilities, with major outstanding of USP 70.108, USP 70.010, and BRS 133 parents for PG and FP. The parent USP 70.042 was the most divergent and showed positive dominance for PG. Both technologies were numerically similar for FP and FT. The conventional technology has the advantage to be statistically more productive (PG and PCS) than transgenic technology. However, the transgenic technology has the advantage to be easier to use and less expensive to soybean producers.

Made available in DSpace on 2017-07-25T19:30:48Z (GMT). No. of bitstreams: 1 GISLAINE GABARDO.pdf: 1835122 bytes, checksum: 11f8d6244d587bd02e0025385165e5a5 (MD5) Previous issue date: 2015-02-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The use of plant defense mechanisms inducers may increase the disease control spectrum in soybean. The objective of this study was to abiotic and biotic resistance inducers in experiments in detached leaves and field conditions in soybean. The experiments with detached leaves were conducted in the laboratory, since the field experiment was conducted at the Fazenda Escola Capão da Onça in the harvest 2013/2014. The experimental design for the experiment of detached leaves was completely randomized in a factorial arrangement (7 x 2), with five replications. The field experiment was adopted the design of a randomized block design with four replications. Treatments for the experiments were: 1 - control; 2 - acibenzolar-S-methyl (Bion 500 WG; 3 - calcium (Max Fruit; 4 - micronutrients: copper, manganese and zinc (Wert Plus; 5 - micronutrients: manganese, zinc and molybdenum (V6; 6 - NK fertilizer (Hight Roots; 7 - Ascophyllum nodosum (Acadian and 8 - azoxystrobin + cyproconazole (Priori XTRA with addition of Nimbus adjuvant. Were evaluated by the detached leaf method inducers against Phakopsora pachyrhizi, Sclerotinia sclerotiorum and Rhizoctonia solani. No difference in treatments for P. pachyrhizi. For Rhizoctonia solani and S. sclerotiorum was no difference highlighting treatment with A. nodusum and micronutrients: copper, manganese and zinc and manganese, zinc and molybdenum, respectively. In the experiment, were made 4 applications of resistance inducers (phenological stages V3, V6, R1 and R5.1) and two of the fungicide (phenological stages R1 and R5.1). The characteristics evaluated were: severity of downy mildew (Peronospora manshurica), powdery mildew (Microsphaera diffusa), rust (P. pachyrhizi), final disease cycle (DFC), defoliation, yield components, yield and germination and health of harvested seeds. With the data of severity calculated the area under the disease progress curve (AUDPC). Substitutes controlled the mildew, but had no effect on powdery mildew, rust, DFC and defoliation. The fungicide treatment was the one who controlled the rust, powdery mildew, DFC and defoliation. Cultivate the yield components those affected by the treatments were the number of pods per plant and thousand kernel weight. Treatment with fungicide had the highest productivity. Defoliation was strongly correlated with the PMG, emphasizing the importance of maintaining the leaf area to ensure grain filling. Foliar treatments and the best treatments NK fertilizer and fungicide affected the germination and seed health. / O uso de indutores de mecanismos de defesas das plantas pode aumentar o espectro de controle das doenças na cultura da soja. O objetivo deste trabalho foi estudar indutores de resistência abióticos e biótico em experimentos em folhas destacadas e em condições de campo na cultura da soja, com a cultivar BMX Potencia RR. Os experimentos com folhas destacadas foram conduzidos em laboratório, já o experimento em campo foi conduzido na Fazenda Escola Capão da Onça na safra 2013/2014. O delineamento experimental para o experimento das folhas destacadas foi o inteiramente casualizado em esquema fatorial 7 (tratamentos) x 2 (aplicação ou não do produto em metade da mesma folha), com cinco repetições. No experimento em campo foi adotado o delineamento de blocos ao acaso com quatro repetições. Os tratamentos para os experimentos foram: 1 - testemunha; 2 - acibenzolar-S-metílico (Bion 500 WG); 3 - cálcio (Max Fruit); 4 - micronutrientes: cobre, manganês e zinco (Wert Plus); 5 - micronutrientes: manganês, zinco e molibdênio (V6); 6 - adubo NK (Hight Roots); 7 - Ascophyllum nodosum (Acadian) e 8 - azoxistrobina + ciproconazol (Priori XTRA®) com adição do adjuvante Nimbus. Foram avaliados, pelo método da folha destacada os indutores contra Phakopsora pachyrhizi, Sclerotinia sclerotiorum e Rhizoctonia solani. Não houve diferença dos tratamentos para P. pachyrhizi. Para S. sclerotiorum e R. solani houve diferença destacando-se o tratamento com A. nodusum e micronutrientes: cobre, manganês e zinco e manganês, zinco e molibdênio, respectivamente. No experimento no campo foram realizadas 4 aplicações dos indutores de resistência (estádios fenológicos V3, V6, R1 e R5.1) e duas do fungicida (estádios fenológicos R1 e R5.1). As variáveis avaliadas foram: severidade de míldio (Peronospora manshurica), oídio (Microsphaera diffusa), ferrugem asiática (P. pachyrhizi), doenças de final de ciclo (DFC), desfolha, componentes de rendimento, produtividade e germinação e sanidade das sementes colhidas. Com os dados de severidade calculou-se a área abaixo da curva do progresso das doenças (AACPD). Os produtos alternativos controlaram o míldio, mas não apresentaram efeito sobre o oídio, ferrugem asiática, DFC e desfolha. O tratamento com fungicida foi o único que controlou a ferrugem asiática, oídio, DFC e diminuiu a desfolha. Os componentes de rendimento da cultivar que foram afetados pelos tratamentos foram o número de vagens por planta e peso de mil grãos. O tratamento com o fungicida proporcionou a maior produtividade. A desfolha foi fortemente correlacionada com o PMG, ressaltando a importância da manutenção da área foliar para assegurar o enchimento de grãos. A germinação e sanidade de sementes foram afetadas pelos tratamentos foliares sendo os melhores tratamentos com adubo NK e com o fungicida.

Submitted by Angela Maria de Oliveira (amolivei@uepg.br) on 2019-02-06T18:32:21Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Gislaine Gabardo.pdf: 2546849 bytes, checksum: 3e5114c040fc11f334d987259a7b5968 (MD5) / Made available in DSpace on 2019-02-06T18:32:21Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Gislaine Gabardo.pdf: 2546849 bytes, checksum: 3e5114c040fc11f334d987259a7b5968 (MD5) Previous issue date: 2018-12-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O objetivo deste trabalho foi avaliar a aplicação de produtos alternativos isolados e associados a fungicida em diferentes épocas de semeadura na eficiência no controle de doenças foliares, alterações fisiológicas, desfolha, componentes de rendimento, produtividade e qualidade fisiológica das sementes obtidas na cultura da soja (Glycine max). Foram conduzidos experimentos à campo em Ponta Grossa, PR, Brasil, durante as safras 2015/2016, 2016/2017 e 2017/2018 com as cultivares NA 5909 e TMG 7062. Os tratamentos para os experimentos foram: 1 - testemunha (água) (V4, V6, R1 e R5.1), 2 - Bacillus subtilis linhagem QST (V4, V6, R1 e R5.1), 3 - Bacillus subtilis linhagem QST (V4 e V6) associado a azoxistrobina + benzovindiflupir (R1 e R5.1), 4 - quitosana 1% (V4, V6, R1 e R5.1), 5 - quitosana 1% (V4 e V6) associado a azoxistrobina + benzovindiflupir (R1 e R5.1), 6 - enxofre (V4, V6, R1 e R5.1), 7 - enxofre (V4 e V6) associado a fungicida (R1 e R5.1), 8 - hipoclorito de sódio (V4, V6, R1 e R5.1), 9 - hipoclorito de sódio (V4 e V6) associado a azoxistrobina + benzovindiflupir (R1 e R5.1), 10 - azoxistrobina + benzovindiflupir (R1 e R5.1), 11 - azoxistrobina + benzovindiflupir (V6, R1 e R5.1). Em todos os tratamentos com fungicida foi adicionado o adjuvante Nimbus® (0,5 v/v). Na semeadura em outubro ocorreu a menor severidade de doenças. A área abaixo da curva de progresso da doença (AACPD) da ferrugem asiática foi menor na cultivar TMG 7062, nas duas épocas de semeadura e safras. Em todas as safras e épocas de semeadura, os tratamentos alternativos com enxofre e quitosana (isolados), os tratamentos alternativos associados ao fungicida e o fungicida aplicado duas e três vezes, diminuíram a severidade da ferrugem asiática e do oídio nas duas cultivares. O fungicida elevou os teores de clorofila α, β e total na cultivar TMG 7062. A cultivar TMG 7062 apresentou maior condutância estomática, assimilação de CO2 e transpiração, em relação à NA 5909. A desfolha foi reduzida para as duas cultivares nos tratamentos com enxofre isolado; os produtos alternativos associados ao fungicida e o fungicida aplicado em duas ou três vezes, em todas as safras e épocas de semeadura. Os componentes de rendimento afetados foram o número de vagens por planta e a massa de mil grãos. Houve redução na produtividade quando a cultura foi semeada em dezembro. A cultivar TMG 7062, na primeira época de semeadura não respondeu aos tratamentos para a produtividade. Os tratamentos com fungicida, enxofre, bem como os produtos alternativos associados, evitaram danos a produtividade em todas as épocas de semeadura, safras e cultivares. Destacou-se o tratamento de enxofre associado ao fungicida que foi equivalente ao tratamento com fungicida aplicado três vezes, havendo possibilidade da inserção desta estratégia de manejo pelos produtores da região. Com relação as sementes obtidas, a cultivar NA 5909 apresentou maiores valores de germinação que a TMG 7062. Os produtos alternativos testados não apresentaram efeitos fitotóxicos à germinação das sementes das duas cultivares. Na segunda época de semeadura ocorreu menor incidência de patógenos nas sementes fato que pode justificar a maior germinação nesta época para as duas cultivares. Os tratamentos que reduziram a incidência de patógenos nas sementes foram o fungicida isolado, B. subitilis e o enxofre, isolados e associados ao fungicida nas duas cultivares analisadas. Não houve diferença para a germinação e sanidade das sementes submetidas a duas ou três aplicações foliares do fungicida. / The objective of this work was to evaluate the application of alternative products isolated and associated to fungicide in different sowing dates in the control efficiency of foliar diseases, physiological changes, defoliation, yield components, productivity and physiological quality of the seeds obtained in the soybean crop (Glycine max). Experiments were conducted in the field in Ponta Grossa, PR, Brazil, during the 2015/2016, 2016/2017 and 2017/2018 growing seasons with cultivars NA 5909 and TMG 7062. Treatments for the experiments were: 1-control (water) (V4, V6, R1 and R5.1), 2- Bacillus subtilis strain QST (V4, V6, R1 and R5.1), 3-Bacillus subtilis strain QST (V4 and V6) associated with azoxystrobin + benzovindiflupir (R1 and R5. 1), 4-chitosan 1% (V4, V6, R1 and R5.1), 5-chitosan 1% (V4 and V6) associated with azoxystrobin + benzovindiflupir (R1 and R5.1), 6-sulfur (V4, V6 , R1-R5.1), 7-sulfur (V4 and V6) associated with fungicide (R1 and R5.1), 8-sodium hypochlorite (V4, V6, R1 and R5.1), 9- sodium hypochlorite ( V4 and V6) associated with azoxystrobin + benzovindiflupir (R1 and R5.1), 10-azoxystrobin + benzovindiflupir (R1 and R5.1), 11-azoxystrobin + benzovindiflupir (V6, R1 and R5.1). In all treatments, Nimbus® adjuvant (0.5 v / v) was added. At the sowing in october the lowest disease severity occurred. The Asian rust area under the disease progress curve (AACPD) was lower in the cultivar TMG 7062, in the two sowing dates and growing seasons. In all growing seasons and sowing dates, alternative treatments with sulfur and chitosan (isolated), alternative treatments associated with fungicide and fungicide applied twice and three times, decreased the severity of Asian rust and powdery mildew in both cultivars. The fungicide increased the levels of chlorophyll α, β and total in cultivar TMG 7062. The cultivar TMG 7062 presented greater stomatal conductance, assimilation of CO2 and perspiration, in relation to NA 5909. The defoliation was reduced for both cultivars in the treatments with: sulfur isolated; the alternative products associated to the fungicide and the fungicide applied in two or three times, in all the seasons and sowing dates. The yield components affected were the number of pods per plant and the thousand grains weight. There was a reduction in productivity when the crop was sown in December. The cultivar TMG 7062 in the first sowing date did not respond to treatments for yield. The treatments with fungicide, sulfur, as well as the associated alternative products, prevented damages to productivity in all sowing dates, growing seasons and crops and cultivars. The sulfur treatment associated to the fungicide that was equivalent to the treatment with fungicide applied three times was highlighted, being possible the adaption of this management strategy by the producers of the region. Regarding the seeds obtained, the cultivar NA 5909 presented higher values of germination than the TMG 7062. The alternative products tested did not present phytotoxic effects to the seed germination of the two cultivars. In the second sowing dates there was a lower incidence of seed pathogens, which may justify the higher germination for both cultivars. The treatments that reduced the incidence of pathogens in the seeds were the isolated fungicide, B. subitilis and sulfur, isolated and associated to the fungicide in the two cultivars analyzed. There was no difference for the germination and sanity of the seeds submitted to two or three foliar applications of the fungicide.

Soybean rust (SBR) caused by Phakopsora pachyrhizi Syd. is an aggressive wind dispersed fungal disease which has spread around the world at an alarming rate in the last decade. The disease was first reported in South Africa (SA) in 2001. It has become well established in the province of KwaZulu-Natal. Reports are occasionally made from eastern Mpumalanga, late in the growing season, in years with good rainfall. Yield losses of 10 - 80% have been reported due to SBR infection. Literature was reviewed to better understand the pathogen in an attempt to find suitable disease management strategies. Many strategies involve delaying, rather than preventing, SBR infection. Of the two strategies to prevent infection, the use of fungicides was the only option for disease control in SA, as no resistant cultivars are available. Field trials were conducted to determine which fungicides are effective in controlling SBR. Further research was conducted to determine the timing, frequency and rate of fungicide applications for optimal control of SBR. Trials were evaluated for disease severity, seed yield and the effect of fungicides on seed quality. Fungicides from the triazole class of the sterol biosynthesis inhibiting group of fungicides were found to be the most effective in controlling SBR. A fungicide from the strobilurin group was found to be less effective than the triazoles at the suggested rate, but was found to be as effective when evaluated at higher dosage rates. Triazoles premixed with fungicides from the benzimidazole and strobilurin groups were also effective in controlling SBR. Timing of application was found to be critical for strobilurin fungicides, but not for triazole fungicides, which have a curative ability, unlike strobilurins. Strobilurin fungicides applied preventatively, before the appearance of disease symptoms were as effective as triazole fungicides applied after disease symptoms, but before infection levels had reached 10%. Across both wet and dry seasons two fungicide applications applied at 21d intervals at the R2 growth stage resulted in effective disease control. In wet seasons, a third fungicide application resulted in yields that were higher, albeit not statistically significant, than two fungicide applications. Assessments of individual fungicides for optimal dosage rate found that registered rates were already optimal for some fungicides, but for others it appeared as if alterations were necessary to the rate suggested for registration. This study was one of the first to extensively evaluate the efficacy of the new triazole and strobilurin fungicides on SBR control. The results have been shared globally, but particularly with newly affected countries in South and North America. Although this research has been groundbreaking, there are still many aspects of fungicide control which need to be studied in order to further optimise chemical control of SBR. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2005

Phakopsora pachyrhizi H. Syd and P. Syd, the causal organism of soybean rust (SBR) was first reported in Japan in 1902. In 1934 the pathogen was found in several other Asian countries and as far south as Australia. In India, SBR was first reported on soybeans in 1951. There have been several early reports of SBR in equatorial Africa but the first confirmed report of P. pachyrhizi on the African continent was in 1996 from Kenya, Rwanda and Uganda. Since then, the pathogen has spread south with reports from Zambia and Zimbabwe in 1998 and in Mozambique in 2000. In February 2001, P. pachyrhizi was first detected on soybeans near Vryheid, in Northern KwaZulu-Natal, South Africa (SA). As the season progressed, the disease was observed in other parts of the province, and epidemic levels were found in the Cedara, Greytown, Howick and Karkloof production regions. Soybean rust subsequently spread to Amsterdam and Ermelo in the Highveld region of SA. The disease reappeared in SA in March 2002. It is now established that the pathogen is a threat to soybean production in the country with yield losses in the region of 10-80%. A literature review on SBR investigating the taxonomy of the pathogen, its morphology, symptoms, host range, infection process, epidemiology, control options and the economic importance of P. pachyrhizi was complied to provide the necessary background information to conduct research under local conditions and to assist in interpretation of results of experiments. Epidemiological trials were conducted at the University of KwaZulu-Natal under controlled environmental conditions in a dew chamber and conviron. Development of P. pachyrhizi on the susceptible cultivar (LS5995) was quantified in combinations of seven temperatures (15,19,21,24,26,28 and 30°C) and five leaf wetness durations (LWD) (6,9,12,14 and 16hrs) at three relative humidities (RH) (75%, 85% and 95%). Studies indicate that optimum temperature for uredospore infection is 21-24°C with a LWD greater than 12hrs and RH 85-95%. The number of pustules as well as lesion size on the abaxial and adaxial leaf surface increased with increasing LWD at all the RH values tested. Infection did not occur on plants incubated at 15°C and 30°C at 85% or 95%RH whereas at 75%RH infection did not occur on plants incubated at 15°C, 19°C and 30°C regardless of LWD. Number of pustules per lesion produced at 75%, 85% and 95%RH was highest at 24°C and showed a gradual increase with increasing LWD. Lesion size on both leaf surfaces increased after 12hrs LWD at 24°C at 75% and 85%RH whereas at 95%RH lesion size increased after 14hrs LWD at 24°C. Exposure of uredospores to ultraviolet light which is equivalent to ultraviolet C (sunlight) which is < 280nm, shows a decrease in germination (7%). Under continuous darkness, the germination percentage was found to range from 58% after 48 hrs. Germination was found to peak at 16hrs in darkness with a gradual decrease as time increased whereas germination under ultraviolet light was highest after 6hrs with a gradual decrease with increased exposure to light. Germ tube lengths were found to be shorter when exposed to ultraviolet light (107µm) compared to controls kept in the dark (181µm). Results obtained clearly show a negative effect of ultraviolet light on the germination and germ tube length of uredospores. A 0.1 ml suspension of uredospores on 1.25% water agar Petri dishes was exposed to cycles of 14h ultraviolet light and 10h darkness for 48h. Results indicate an increase in germination percentage of uredospores when exposed to 10h of darkness following a 14h period under ultraviolet light. Controlled environmental studies were conducted to determine alternative hosts of P. pachyrhizi in SA. The control used in this experiment was Prima 2000, a susceptible cultivar to soybean rust. Seven legume plants [Cajanus cajan (L.) Huth, Glycine max (L.) Merr, Lablab purpureus (L.) Sweet, Lupinus angustifolius (L.) Finnish, Phaseolus vulgaris (L.), Pueraria lobata (M&S) Wild and Vigna unguiculata (L.) Walp] and three dry bean lines (Bonus; OPS-RS2 and PAN 159) showed typical SBR symptoms when rated after 21 days post inoculation with uredospores for percentage disease severity. Disease severity was significantly different within the alternative hosts, but G. max, P. vulgaris and P. lobata were not significantly different from Prima 2000 (control). A uredospore suspension of 2.5 x 10(5) uredospores ml(-1) from plants that showed typical SBR symptoms was made and inoculated on to Prima 2000, a susceptible soybean cultivar. Uredospores from pustules on G. max, L. purpureus, L. angustifolius, P. vulgaris, P. lobata, V. unguiculata, Bonus and PAN 159 produced viable uredospores on PRIMA 2000. These plants are considered alternative hosts of P. pachyrhizi. Effect of leaf age on susceptibility of soybean to SBR was tested under controlled environmental conditions. Mean number of lesions as well as lesion size were greater on younger leaves than on older leaves of plants at the same physiological age. Plants at the early vegetative and reproductive stages had a significantly lower number of lesions as well as a smaller lesion size. Plants at the V6 and R1 growth stages were significantly more susceptible to P. pachyrhizi than plants at other developmental stages. Trichoderma harzianum Rifai, Eco-77® a commercial biological control product, was evaluated for its efficacy as a biological control agent of P. pachyrhizi. Trichoderma harzianum sprayed at the standard concentration on infected soybean plants was significantly more effective in controlling P. pachyrhizi than plants sprayed at 1/2X and 2x the standard concentration. This was noted in both Trial 1 and 2. Data indicate that spraying the filtrate two days after inoculation produces less disease. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / The efficiency of a fungicide is the result of the combination of a variety of factors including: time of application, environmental conditions, physiological condition of plant and application technology used. Already to the latter the proper the deposition and distribution of the active ingredient in the target is decisive for efficiency. The objective of this study was to evaluate the optimal droplet spectrum depending on the characteristics of plant architecture of soybean varieties. Two trails were conducted in the experimental area Phytus Institute in the city of Itaara, central region of Rio Grande do Sul in 2009/2010. The trial consisted of comparison of eight cultivars with different architectural characteristics of the plant with fungicide application using fine droplet spectrum. In Experiment 2, four cultivars were tested with application of fungicide using four spectra drops (very fine, fine, medium and coarse). To evaluate the effect of the treatments were assessed the following parameters: number of drops.cm-2, volume median diameter, Leaf Area Index, plant height, number of branches.plant-1, AUCPD, percentage of incident light in the canopy, yield soybean and yield components. The data of trial 1 showed that the architecture of plants (plant height, number of branches.plant-1 and LAI) significantly affected the deposition of droplets in the bottom and middle of the cultivars. It can also be inferred that the soybean cultivars are grouped due to their architectural characteristics allowing coverage similar drops. In trial 2, the application of fungicides with different droplet spectra allowed significant variations in disease control and on soybean yield. The fine droplet spectrum was more control and consistency in droplet deposition between the four cultivars. / A eficiência de um fungicida é o resultado da associação de uma série de fatores como: momento da aplicação, condições ambientais, condição fisiológica da planta e tecnologia de aplicação utilizada. Já para esta última a adequada deposição e distribuição do ingrediente ativo no alvo é determinante para eficiência do processo. O objetivo deste trabalho foi determinar o espectro de gotas ideal em função das características de arquitetura de planta de cultivares de soja. Foram conduzidos dois experimentos na área experimental do Instituto Phytus, no município de Itaara, região central do Rio Grande do Sul na safra 2009/2010. O experimento 1 consistiu do comparativo de oito cultivares com características variadas de arquitetura de planta com aplicação de fungicida utilizando espectro de gotas fino. No Experimento 2, foram testadas quatro cultivares com aplicação de fungicida utilizando quatro espectros de gotas (muito fino, fino, médio e grosso). Para avaliar o efeito dos tratamentos foram determinados os seguintes parâmetros: número de gotas.cm-2, diâmentro mediano volumétrico, Índice de Área Foliar, estatura de plantas, número de ramos.planta-1, AACPFa, percentual de luz incidente no dossel produtividade da soja e componentes do rendimento. Os dados do experimento 1 indicaram que a arquitetura de plantas (estatura de plantas, número de ramos.planta-1 e IAF) influenciou significativamente a deposição de gotas no terço inferior e médio das cultivares. Também pode-se inferir que as cultivares de soja se agrupam em função de suas características de arquitetura permitindo cobertura de gotas semelhante. No experimento 2 a aplicação de fungicida com diferentes espectros de gotas possibilitaram variações significativas no controle da doença bem como na produtividade da soja. O espectro de gotas fino teve maior consistência no controle e deposição de gotas entre as quatro cultivares.

Currently, the Asian soybean rust is the main disease of this crop in Brazil and chemical control, so far, is the only effective measure to reduce losses. The development of control strategies for this disease requires knowledge of how performance of products applied, application technology used as well as their interaction with plants. This work aimed to quantify the effect of large, medium and fine droplet spectra and its interaction with the fungicide absorption rate and leaflets age through indirect measure expressed by the control of Phakopsora pachyrhizi in soybean. The experiment was performed twice and that was first installed in January 2010 and repeated in March this year. The experimental design was composed by completely randomized design with four replications in a factorial (3x3x5x4), which factors were composed of: three spectra drops (large, medium and fine); factor 02: evaluation in different positions of the plant (1º, 3º and 5 leaflets), factor 03: four time periods between the fungicide application and simulated rain (0, 30, 60 and 120 ) and a control with no rain and still a factor 04: control without fungicide applying, Azoxystrobin+Cyproconazole (60+24 g a.i. ha-1) + Nimbus 0.6 L.ha-1, Azoxystrobin (50 g a.i. ha-1) + Nimbus 0.6 L.ha-1 and Cyproconazole (30 g a.i. ha-1). We evaluated the density of droplets per square centimeter, volume median diameter, number median diameter and relative amplitude, disease severity and area under the disease progress curve. It was found that drops with smaller volume median diameter have higher fungicides absorption rates because they provide a greater number of drops per square centimeter and hence larger contact area specific product / plant. Newer leaflets provide more quickly fungicides absorption and therefore, provide a longer delay in disease development. The use of Azoxystrobin + Cyproconazole provided the greatest number of days until the first pustule preview and smaller area under the disease progress curve. The influence of rain has highly dependent on the interval between application of the products and its occurrence, the product applied and tissues age considered. / Atualmente a ferrugem asiática da soja é a principal doença desta cultura no Brasil e o controle químico, até então, é a medida mais eficaz para a redução dos danos causados. O desenvolvimento de estratégias de controle desta doença requer o conhecimento da forma de atuação dos produtos aplicados, tecnologia de aplicação utilizada bem como de sua interação com a planta. Com este trabalho buscou-se quantificar o efeito de espectros de gotas grossas, médias e finas na velocidade de absorção de fungicidas para trifólios de diferentes idades através de medida indireta expressa pelo controle de Phakopsora pachyrhizi na cultura da soja. O experimento foi executado duas vezes sendo que foi instalado primeiramente em Janeiro de 2010 e repetido em Março deste mesmo ano. O delineamento experimental utilizado foi inteiramente casualizado, com quatro repetições, em arranjo fatorial (3x3x5x4), cujos fatores foram compostos por: três espectros de gotas (grossas, médias e finas); fator 02: avaliação em diferentes posições da planta (1º, 3º e 5º trifólios); fator 03: quatro períodos de tempo entre a aplicação de fungicidas e aplicação de chuva simulada (0, 30, 60 e 120 min), mais uma testemunha sem chuva e ainda fator 04: testemunha sem aplicação mais os fungicidas Azoxistrobina + Ciproconazol (60+24 g i.a. ha-1) + Nimbus 0,6 L.ha-1, Azoxistrobina (50 g i.a. ha-1) + Nimbus 0,6 L.ha-1 e Ciproconazol (30 g i.a. ha-1). Avaliou-se densidade de gotas por centímetro quadrado, diâmetro mediano volumétrico, diâmetro mediano numérico e amplitude relativa, severidade da doença e área abaixo da curva de progresso da doença. Verificou-se que gotas de menor DMV apresentam maior velocidade de absorção de fungicidas, pois proporcionam maior número de gotas por centímetro quadrado e conseqüentemente maior área específica de contato produto/planta. Trifólios mais novos absorvem os fungicidas mais rapidamente e, em conseqüência, estabelecem um maior atraso no desenvolvimento da doença. A utilização de Azoxistrobina + Ciproconazol proporcionou o maior número de dias até o aparecimento da primeira pústula e menor área abaixo da curva de progresso da doença. A influência da precipitação possui relação altamente dependente do intervalo entre a aplicação dos produtos e a ocorrência da mesma, do produto que está sendo aplicado e da idade dos tecidos considerados.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The suitability of application technology, particularly with regard to spray nozzles and spray rates to the target characteristics, mainly related to plant architecture, can improve the quality of the deposition of fungicides, which in turn can maximize efficiency of asian rust control and soybean yield. This study aimed to evaluate the control of the asian rust and yield of soybean due to the application of fungicides with different spray nozzles and spray rates on cultivars with different plant architectures. For this purpose an experiment was conducted in Itaara - RS, in a randomized block design with split plots and two of the factors arranged in bands. The first factor (cultivars) were arranged in bands on the main plots. The second factor (nozzles) was placed in bands in the subplots and the third factor (spray rates) were randomized within subsubplots. Were used four replications (blocks). Were used soybean cultivars A 6411 RG, BMX Apollo RR, TMG 4001 RR, A 7636 RG and BMX Potência RR. As a second factor, were used the spray nozzles XR11001, TJ-6011002 and TXA800067 and as the third factor application rates 70, 100 and 130 L.ha-1, plus a control without application. There were two applications of fungicides. The parameters evaluated were leaf area index (LAI) stratified by thirds of the canopy, the percentage of luminance within the lower and middle thirds of the canopy, the percentage of canopy closure, the number of branches.m-2, height plant, the shape of leaves, the relative chlorophyll content in the three thirds of the canopy, the density, DMV, homogeneity and relative amplitude of the drops, the severity of the asian rust and yield and thousand grain weight stratified in three thirds canopy. The results indicate the need for parameters spray nozzles and spray rates are adjusted to the plant architecture of the cultivars, especially the leaf area index (LAI) and plant height. / A adequação da tecnologia de aplicação, principalmente no que se refere a pontas de pulverização e taxas de aplicação,às características do alvo, relacionadas principalmente a arquitetura de plantas, pode melhorar a qualidade da deposição dos fungicidas, que por sua vez pode maximizar da eficácia de controle da ferrugem asiática e a produtividade da soja.O presente trabalho objetivou avaliar o controle da ferrugem asiática e a produtividade da cultura da soja em função da aplicação de fungicidascom diferentes pontas de pulverização etaxas de aplicação em cultivares com diferentes arquiteturas de planta. Para isso foi conduzido um experimento em Itaara RS, no delineamento blocos ao acaso com parcelas subsubdivididas e com dois dos fatores dispostos em faixas. O primeiro fator (cultivares) foi disposto em faixas sobre as parcelas principais. O segundo fator (pontas) foi disposto em faixas nas subparcelas e o terceiro fator (taxas de aplicação) foi casualizado dentro das subsubparcelas. Foram utilizadas quatro repetições (blocos). Foram utilizadas as cultivares de soja A 6411 RG, BMX Apolo RR, TMG 4001 RR, A 7636 RG e BMX Potência RR. Como segundo fator, foram utilizadas as pontas de pulverização XR11001, TJ-6011002 e TXA800067 e, como terceiro fator as taxas de aplicação 70, 100 e 130 L.ha-1, mais um tratamento testemunha sem aplicação. Foram realizadas duas aplicações de fungicidas. Os parâmetros avaliados foram o índice de área foliar (IAF) estratificado por terços do dossel, o percentual de iluminância no interior dos terços inferior e médio do dossel, o percentual de fechamento do dossel, o número de ramos.m-2, a estatura das plantas, o formato das folhas, o teor relativo de clorofila nos três terços do dossel, densidade, DMV, homogeneidade e amplitude relativa das gotas nos três terços do dossel, a severidade da ferrugem asiática, a produtividade e a massa de mil grãos estratificada nos terços do dossel. Os resultados obtidos indicam a necessidade de os parâmetros de aplicação pontas de pulverização e taxas de aplicação serem ajustados em função da arquitetura das cultivares, principalmente ao índice de área foliar (IAF) e estatura de plantas.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The mineral nutrition is a tool that can be used in the management of diseases in soybean. Plants grown under adequate nutritional levels are more tolerant to attack by certain pathogens. Calcium is a structural component of the cell wall, its availability directly affects the mechanical strength of tissues and thus the reaction of the plant to plant pathogens. Other cropping practices than fungicides have to be searched to avoid excessive exposure of fungi to the same active ingredients, a fact favoring the emergence of resistant individuals. The study aimed to determine the effect of calcium availability on the severity of Asian soybean rust, plant growth and grain yield in two cultivars. The experiment was conducted in pots with sand in a greenhouse, from December 2, 2013 to April 15, 2014. The treatments consisted of a split-split-plot factorial (5x2x2) design, with five calcium concentrations in nutrient solution, two soybean cultivars and with and without chemical fungicide control. Seven evaluations of disease severity were made during the plant vegetative and reproductive stages and the area under the disease progress curve (AURPC) was determined. At the end of the experiment, shoot dry weight, grain production, total number of grains per plant, thousand grain weight and the leaf calcium content were determined. Results indicated that by increasing calcium availability shoot growth was enhanced and disease severity was reduced, grain production was increased in plants without chemical control, with interactions between cultivars. It was concluded that calcium nutrition can be used in crop management to reduce the severity of the Asian soybean rust. / A nutrição mineral é uma ferramenta que pode ser utilizada no manejo de doenças em soja. Uma planta com níveis nutricionais adequados é mais tolerante ao ataque de determinados fitopatógenos. O cálcio é componente estrutural da parede celular, sua maior ou menor disponibilidade afeta diretamente a resistência mecânica dos tecidos e, consequentemente, a reação da planta aos fitopatógenos. É necessário que outras formas de manejo sejam adotadas a fim de evitar a exposição excessiva dos fungos aos mesmos ingredientes ativos, fato que favorece o aparecimento de indivíduos resistentes. O trabalho teve por objetivo determinar o efeito da disponibilidade de cálcio sobre a severidade da ferrugem asiática da soja, o crescimento da planta e a produtividade de grãos em duas cultivares. O experimento foi conduzido em vasos com areia em casa de vegetação, entre 02 de dezembro de 2013 e 15 de abril de 2014. Os tratamentos foram constituídos de um fatorial (5x2x2), com parcelas sub subdivididas, cinco concentrações de cálcio em solução nutritiva, duas cultivares e com e sem aplicação do tratamento químico fungicida. Foram feitas sete avaliações da severidade da doença no estádio vegetativo e reprodutivo das plantas e determinada a área abaixo da curva de progresso da ferrugem (AACPF). Ao final do experimento foi determinada a massa seca da parte aérea, a produção de grãos, o número total de grãos por planta, o peso de mil grãos e o teor de cálcio nas folhas. Os resultados indicaram que o aumento da disponibilidade de cálcio aumentou o crescimento da parte aérea e diminuiu a severidade da doença, com aumento na produção de grãos nas plantas sem aplicação de fungicida, havendo interações com a cultivar. Concluiu-se que a nutrição com cálcio pode ser empregada no manejo da cultura visando reduzir a severidade da ferrugem asiática.