ABSTRACT Anthracnose caused by Colletotrichum horii is one of the most important diseases in the persimmon tree. This study aimed to determine the influence of environmental variables on conidia germination, mycelial growth, and infection in persimmon fruit and shoots/twigs. The germination was quantified at 10, 15, 20, 25, and 30°C, with 6, 12, and 24 hours of wetness period. The effects of the same temperatures were also evaluated for mycelial growth, sporulation, and infection on ‘Fuyu’ fruit. The infection on shoots/twigs were quantified at 5, 10, 15, 22, 25, 27, and 35°C. The conidia germinated at all temperatures and wetness combinations, except at 10°C, with 6 hours of wetness. At 24 hours of wetness, the optimal temperature for conidia germination was 21.3°C. The optimal temperature for mycelial growth ranged between 21.7 to 24.3°C. The optimal temperature for lesion growth on fruit was 25.7°C; at 25°C, the incubation period was of two days, and the latent period lasted 12 days. On shoots/twigs, the temperature of 35°C anticipated in two days the onset of symptoms and 5-10°C delayed in eight-10 days the onset of symptoms in relation to temperature of 25°C. In nonlignified shoots, C. horii can cause symptoms from 15 to 35°C. In lignified twigs, C. horii was able to cause symptoms from 5 to 35°C. Because of the incidence and disease progression in most of climatic situations, our results reinforce the importance of monitoring and constantly removing diseased shoots, twigs, and fruits from the orchard to reduce the spread of the pathogen.

ABSTRACT. Several diseases are difficult to control specially in subtropical regions and perennial hosts where the pathogen survive easily within the plant. The aim of this study was to identify which pathogens are surviving after end of one season and at the beginning of the next season to inform which pathogens represent potential risk as primary inoculum to the next season. Survival of pathogens on apple tree twigs was evaluated during dormancy and on beginning of vegetative growth in four orchards located in the two main apple production regions: Palmas and metropolitan region of Curitiba, in Paraná State, Brazil. For this purpose, 10 cm long asymptomatic twigs were collected from 10 randomly selected plants, 24 twigs per plant. Half of the twigs were left directly (without disinfection) in humid chambers for 30 days at 25ºC. The other half of the twigs were disinfected and kept in a freezer for 12 hours at -16ºC by the Over Night Freezing Incubation Technique (Onfit) and then kept in a humid chamber for 30 days at 25ºC. The fungi Colletotrichum sp., Botryosphaeria sp., Alternaria sp., and Fusarium sp. were detected in the two sampled dates and methodologies in all evaluated regions. Neonectria ditissima was only detected in both orchards from Palmas. The genera found surviving on twigs were confirmed molecularly by BLASTn and were pathogenic in wounded fruits from the cultivar ‘Gala’. Our results indicate that pathogens are surviving in orchards after winter treatment and throughout the apple season, being potential sources of inoculum for infections in flowers and fruits, where the pathogens detected cause important diseases as bitter rot, Neonectria fruit rot, white and black rots, and possibly cause Alternaria and Fusarium rots which have not been extensively studied in Brazil.

ABSTRACT The Glomerella leaf spot (GLS) and bitter rot (BR) are important apple diseases in Brazil, caused by species of Colletotrichum, which are usually related with quiescent infection. This study aimed to detect quiescent infections of Colletotrichum spp. in flowers and in unripe fruits from apple commercial orchard cultivars Eva and Gala. The pathogen was observed in various structures of the flower in both cultivars. In unripe fruits, the pathogen was recovered only from ‘Eva’. Five isolates were obtained and were inoculated by mycelial (with and without wound) on ripe apple fruits and by conidia suspension (without wound) on ripe apple fruits and leaves of ‘Gala’. On inoculated fruits by mycelial, the isolates induced symptoms of BR, and on inoculated fruits by conidia without wound the isolates induced symptoms of GLS. On inoculated leaves, isolates induced symptoms of GLS. The isolates were characterized by cultural, morphological and pathogenic aspects. Detection of Colletotrichum spp. in asymptomatic apple flowers is epidemiologically important, since the flowers can be a route for infection in unripe fruits. This is the first investigation of quiescent infection of this pathogen on apple flowers.

RESUMO: O caquizeiro foi introduzido no Brasil no final do século XIX. Esta planta é conhecida por sua rusticidade e produtividade. No entanto, a doença antracnose está causando queda e sintomas em frutos imaturos, ramos, flores e galhos no campo. O agente causal foi descrito inicialmente como Colletotrichum hori (confirmado usando apenas a região ITS) causando cancro de galho e sintomas de folhas. Neste estudo, comparamos a agressividade em caqui utilizando uma coleção de 13 isolados de Colletotrichum spp. obtidos de frutos e ramos de caqui da região metropolitana de Curitiba, Paraná, Brasil. Uma análise molecular multilocus foi realizada com base nos genes ITS, GPDH e EF, e os isolados foram confirmados como pertencentes a C. horii. Todos os isolados foram patogênicos em frutos não feridos e feridos, mas diferiram na agressividade. Apenas um isolado não foi patogênico quando inoculado sem ferimento em ramos. A maioria dos isolados foi capaz de causar cancro e morte de ramo, independentemente do ferimento. Neste estudo, enfatizamos a importância das novas brotações como fonte de inóculo primário. Para um próximo estudo, ainda é necessário ampliar as bases epidemiológicas com estudos em campo para estabelecer uma correta estratégia de controle desta doença.

ABSTRACT: The persimmon tree is known for its rusticity and productivity and was first introduced to Brazil in the late 19th century. However, anthracnose disease is causing immature fruit drop and severe disease symptoms in persimmon fruit, shoots, flowers, and twigs. The causal agent was first described as the fungal species, Colletotrichum horii, which was first confirmed using only the ITS region. In this study, we compared the aggressiveness of 13 isolates of Colletotrichum spp. obtained from fruit and shoots of persimmon grown in the Metropolitan Region of Curitiba, Paraná State, Brazil. A multilocus molecular analysis was carried out based on ITS, GPDH, and EF genes, and we confirmed that the isolates were confirmed as C. horii. All isolates were pathogenic for unwounded and wounded persimmon fruit but differed in aggressiveness. Only one isolate was non-pathogenic when inoculated into unwounded persimmon shoots. Most isolates caused cankers and shoot death whether shoots were wounded or unwounded. In this study, we emphasized the importance of shoots as a source of primary inoculum. In future studies, it will be critical to further elucidate the epidemiological basis of anthracnose disease by conducting field studies to establish a more effective strategy for disease control.

RESUMO A mancha-bacteriana é uma das principais doenças do maracujazeiro amarelo. O objetivo deste estudo foi desenvolver e validar uma escala diagramática para melhorar a acurácia e precisão na avaliação da severidade da mancha-bacteriana em folhas de maracujazeiro-amarelo. A escala diagramática proposta, composta de ilustrações de folhas sintomáticas com nove níveis de severidade (1, 2.5, 5, 10, 20, 30, 40, 50 e 62%), foi validada por 15 avaliadores. A acurácia, precisão e a reprodutibilidade da escala diagramática foram validadas pela quantificação e comparação das avaliações realizadas por 15 avaliadores com e sem o uso da escala diagramática. A escala melhorou a acurácia (fator de correção, Cb= 0,940 sem escala e 0,967, com escala), precisão (coeficiente de correlação, r = 0,901 sem escala e 0,949 com escala) e concordância (coeficiente de correlação de concordância de Lin, ρc = 0,863 sem escala e 0,935 com escala) das estimativas de severidade. A reprodutibilidade entre avaliadores melhorou com o uso da escala (coeficiente de determinação, R2 = 0,717 sem e R2 = 0,880 com a escala, e coeficiente correlação intra-classe ρ = 0,798 sem e ρ = 0,926 com a escala). A escala diagramática desenvolvida melhorou a acurácia, precisão e reprodutibilidade das avaliações da severidade da doença, sendo recomendada como auxiliar na avaliação da mancha-bacteriana em folhas de maracujazeiro-amarelo.

ABSTRACT Bacterial blight is one of the most important diseases of yellow passion fruit. The aim of this study was to develop and validate a set of standard area diagram (SADs) to improve the accuracy and precision of bacterial blight severity assessments on yellow passion fruit leaves. The proposed SADs, composed of illustrations of symptomatic leaves with nine severity levels (1, 2.5, 5, 10, 20, 30, 40, 50 and 62%), were evaluated by 15 raters. Accuracy, precision and reliability of the SADs were validated by quantifying and comparing the assessments performed by 15 raters with and without the use of SADs. The SADs improved accuracy (coefficient of bias, Cb = 0.940 without SADs and 0.967 with SADs), precision (correlation coefficient, r = 0.901 without SADs and 0.949 with SADs) and overall agreement (Lin’s concordance correlation coefficient, ρc = 0.863 without SADs and 0.935 with SADs) of severity estimates. Inter-rater reliability also significantly improved when the SADs were used (coefficient of determination, R2 = 0.717 without and R2 = 0.880 with the SADs; intra-class correlation, ρ = 0.798 without and ρ = 0.926 with the SADs). The developed SADs improved accuracy, precision and reliability of disease severity assessments and are recommended as an aid to assess bacterial blight on yellow passion fruit leaves.

ABSTRACT The increasing consumer demand for fruit quality justifies the development of researches that combine orchards management and consumers’ perception of the quality of the product. The aim of this study was to evaluate the effect of nitrogen fertilization combined with green pruning intensity on fruit quality of ‘Chimarrita’ from high density peach trees during three consecutive harvest seasons. For this purpose, urea composed of different nitrogen rates (0, 40, 80, 120, 160, 200 and 240 kg.ha-1.year-1) was applied, under two intensities of green pruning (annual – once per season; or continuous – four times per season) in a factorial scheme (7 × 2). Fruits have been subjected to physical, chemical and sensorial analysis, made by 60 non-trained evaluators in each of the harvest seasons. The results showed that the cumulative effect of applying N in the third harvest season improved SS attributes, SS/TA ratio and fruit skin color to the dose of N of 148 kg.ha-1 .year-1. There is no difference between green pruning intensity and peach fruit quality.

Resumo O Brasil é o principal produtor mundial de maracujá, mas as ocorrências de doenças têm reduzido sua produtividade e limitado seu cultivo por vários anos em sequência na mesma área. O objetivo deste trabalho foi avaliar a severidade de doenças e a produtividade nos sistemas de condução em espaldeira e em caramanchão durante duas safras, em cultivo anual. Nas safras de 2013/2014 e 2014/2015 o trabalho foi realizado em pomar comercial de maracujazeiro-amarelo em Araquari-SC, testando-se como tratamentos os sistemas de condução em espadeira e em caramanchão em DBC, com oito repetições. Foram realizados os tratos culturais recomendados para a cultura, polinização natural e avaliadas nas duas safras a intensidade da antracnose, da mancha-bacteriana, da cladosporiose e da virose do endurecimento no fruto, de dezembro a junho, a partir do estabelecimento dos sistemas de condução. A produção de frutos por planta e a produtividade estimada foram determinadas. Não houve diferenças nas severidades das doenças avaliadas nos dois sistemas e safras. O sistema em caramanchão mostrou-se mais produtivo (78,1% e 57,1%) do que o sistema em espaldeira, nas safras de 2013/2014 e 2014/2015, respectivamente, demonstrando ser o melhor sistema de condução para o maracujazeiro-amarelo.

Abstract Brazil is the largest producer of passion fruit worldwide, however diseases have been reducing passion fruit productivity, and limiting its cultivation for several years in a row in the same area. The proposal of this study was to evaluate diseases intensity and productivity of yellow passion fruit in vertical and overhead trellis systems, during two seasons, in annual cycle. The experiment was realized in a commercial orchard of yellow passion fruit in the municipality of Araquari, SC, in the 2013/14 and 2014/15 seasons. The treatments were vertical and overhead trellis systems, tested in a randomized complete block design, with eight replications. The agronomic practices were performed according to the culture recommendations and naturally pollinated althoght no disease control was applied. Anthracnose, bacterial blight, cladosporiosis and passion fruit woodiness severities were assessed in two seasons, from December to June, after establishment of the trellis systems. Production of fruits per plant and estimated productivity were determined in both seasons. There were no differences in diseases severity in both systems and seasons. The overhead trellis system was more productive than the vertical trellis system, 78.1% and 57.1% respectively, in the 2013/14 and 2014/15 seasons. Overhead trellis system showed to be the most adequate for yellow passion fruit production.

Resumo Objetivou-se avaliar o período de florescimento e as características físicas e químicas de frutos de pessegueiro, visando a encontrar aqueles mais promissores para a diversificação da persicultura na região metropolitana de Curitiba. Foram avaliados 8 seleções e três cultivares em Porto Amazonas e 10 cultivares em Araucária, quanto ao período de florescimento, frutificação efetiva, diâmetro e altura dos frutos, massa média de frutos, coloração da epiderme, sólidos solúveis (SS), acidez titulável (AT), relação SS/AT, potencial hidrogeniônico (pH). O período de floração ocorreu entre o final de junho e o final de setembro, com variação de 16 a 25 dias. A taxa de frutificação efetiva foi maior que 50% para ‘Cascata 1513’, ‘Cascata 1429’, ‘Cascata 1577’, ‘Cascata 1743 e para todas as cultivares avaliadas em Araucária. Verificaram-se diferenças significativas para as demais variáveis avaliadas. Concluiu-se que em Araucária ‘Charme’ e ‘Chimarrita’ continuam sendo boas opções de plantio na região, têm a mesma duração do ciclo (111 dias), sendo ‘Charme’ um pouco mais tardio. Além desses, ‘Douradão’ e ‘Rubimel’ apresentaram bom tamanho de fruto, melhor balanço entre sólidos solúveis e acidez moderada e são mais precoces que as anteriores. ‘PS 25399’ é o cultivar mais precoce entre todas as avaliadas e apresenta epiderme avermelhada de grande interesse do consumidor. Em Porto Amazonas, as seleções e cultivares testadas produziram poucos frutos e de tamanho pequeno, sendo necessário mais estudo para recomendação nesta área.

Abstract This study aimed to evaluate the flowering period and the physicochemical characteristics of peaches, aiming to find those most promising for the diversification of the peach crop in the Metropolitan Region of Curitiba, Paraná State. We evaluated 8 selections and three cultivars in Porto Amazonas and 10 cultivars in Araucaria for flowering period, fruit set, diameter and height of fruit, average fruit weight, the skin color, soluble solids (SS), titratable acidity (TA), ratio SS/ TA, hydrogen potential (pH). The flowering period occurred between late June and late September ranging from 16 to 25 days. The fruit set rate was greater than 50% for ‘Cascata 1513’, ‘Cascata 1429’, ‘Cascata 1577’, ‘Cascata 1743’ and for all cultivars in Araucaria. There were significant differences for the other variables assessed. It was concluded that in Araucária, ‘Charme’ and ‘Chimarrita’ are good planting options, have the same duration of the cycle (111 days), being ‘Charme’ a little later. Besides these, ‘Douradão’ and ‘Rubimel’ have good fruit size, moderate acidity and best SS/TA ratio, being earlier than the previous ones. ‘PS 25399’ is the earliest and showed reddish epidermis and great consumer interest. In Porto Amazonas, selections and cultivars tested produced little fruit of small size, being required more studies to be recommended in these area.

RESUMO. Sistemas integrados de produção agropecuária (SIPA) são opções sustentáveis para diversificação agrícola, mas existem poucos estudos sobre a influência de SIPA nos microrganismos do solo. Este trabalho investigou a influência de sistemas agropastoril (AP) e agrosilvipastoril (ASP), comparados com lavoura não integrada (CO) na supressão de Rhizoctonia solani e na densidade de propágulos de Fusarium e Trichoderma. No primeiro ensaio, amostras de solo foram inoculadas com R. solani e avaliadas para tombamento da soja. Em seguida, o solo foi esterilizado e reinoculado com o patógeno para uma nova avaliação. Finalmente, 10% do solo nos vasos foi substituído por novas amostras de solo coletadas das mesmas parcelas no campo, para avaliar a transferência da supressividade por amostras de solo. No segundo ensaio, propágulos nativos de Fusarium e Trichoderma foram quantificados em meios semi seletivos. A incidência de tombamento no ASP foi 70% comparada com AP e CO. Avaliações com solo esterilizado e transferido atribuem esta supressão a fatores bióticos. Propágulos de Fusarium foram recuperados no solo do ASP a 70% e 60% das quantidades nos solos do AP e CO, respectivamente. Propágulos de Trichoderma foram recuperados no solo do ASP 150% comparado com AP, mas semelhante ao CO. O sistema agrosilvipastoril no subtrópico brasileiro tem potencial para reduzir patógenos e aumentar microrganismos benéficos no solo.

ABSTRACT. Integrated crop-livestock systems (ICLS) are sustainable options for agricultural diversification, but there have been few studies on the influence of ICLS on soil microorganisms. This work investigated the influence of agropastoral (AP) and agrosilvopastoral (ASP) systems, compared with a non-integrated crop (CO) on the suppression of Rhizoctonia solani and on the density of Fusarium and Trichoderma propagules. In the first assay, soil samples were inoculated with R. solani and evaluated for soybean damping-off. After this, the soil was sterilized and re-inoculated with the pathogen for a new evaluation. Finally, 10% of the soil in the pots were substituted by newly soil samples collected from the same plots in the field to evaluate de suppressiveness transference by soil samples. In the second assay, native Fusarium and Trichoderma propagules were quantified in semi-selective media. Damping-off incidence in ASP was 70% compared to AP and CO. Evaluations with sterilized and transferred soil samples attributed this suppression to biotic factors. Fusarium propagules were retrieved in the ASP soil at 70% and 60% the amounts in AP and CO soils, respectively. Trichoderma propagules were retrieved in the ASP soil at 150% compared to AP, but similar to CO. The agrosilvopastoral system in the Brazilian subtropics has the potential to reduce pathogens and enhance beneficial microorganisms in the soil.

ABSTRACT A shift towards declining azoxystrobin sensitivity has been previously documented in a collection of Brazilian Monilinia fructicola isolates, but information on the stability of this trait after in vitro sub-culturing is not available. In this study, one highly-sensitive isolate and two isolates with reduced sensitivity to azoxystrobin, not exhibiting point mutations at codons 129, 137 and 143 in the target gene of cytochrome b were used. Two independent experiments consisted of 10 weekly transfers of each strain in potato dextrose agar (PDA). Conidial production and germination were quantified in the initial culture and, again, after the third, sixth and tenth transfer. Measures of mycelial growth were obtained in colonies growing on PDA amended with azoxystrobin at 1 µg mL−1 and salicylhydroxamic acid at 100 µg mL−1. Data were normalized to mycelial growth rate after each of the 10 transfers. The colony diameter in the less sensitive isolates was stable across the transfers in the PDA amended with the fungicide. The conidial production and mycelial growth rate did not decrease in non-amended media either. Our results suggest that the trait of reduced sensitivity to azoxystrobin is stable under no selection pressure for azoxystrobin.

RESUMO Trichoderma é um agente de controle biológico utilizado para melhorar a resistência a doenças, que também pode estimular o crescimento de plantas. Produtos comerciais com Trichoderma estão disponíveis em diversos países, mas a maioria baseia-se na suspensão de conídios. Objetivou-se avaliar a eficiência de populações nativas de Trichoderma coletadas de diferentes sistemas de produção e aplicadas ao solo por dois métodos: suspensão de conídios e grãos de aveia infestados. Avaliou-se a eficiência de populações de Trichoderma coletadas de lavoura convencional e sistemas agropastoril e agrossilvopastoril, em experimento de campo de longa duração. A eficiência foi avaliada por testes in vivo, analisando-se o controle de tombamento de soja causado por Rhizoctonia solani, a altura das plantas e a colonização do solo com o antagonista. Os testes in vitro de pareamento de culturas, compostos voláteis e não voláteis foram realizados para explicar o modo de ação das populações. Algumas populações de Trichoderma nativas foram tão eficientes quanto a obtida de produto comercial, em todos os testes. Com grãos de aveia infestados, Trichoderma spp. promoveu maior controle de tombamento, maior altura de plantas e mais unidades formadoras de colônias por grama de solo após três meses da aplicação, quando comparado com a suspensão de conídios. Populações nativas foram igualmente boas ou mesmo melhores do que a cepa comercial, e a utilização de um substrato que suporta o crescimento de Trichoderma foi mais eficiente do que a suspensão de conídios.

ABSTRACT Trichoderma is a biological control agent used to improve the resistance to diseases, which may also estimulate plant growth. Commercial products with Trichoderma are available in different countries, but most of them are based on conidial suspension. This study aimed at evaluating the efficiency of native Trichoderma populations collected from different production systems and applied to the soil by using two methods: conidial suspension and inoculated oat grains. The efficiency of native Trichoderma populations collected from conventional crop and agropastoral and agrosilvopastoral systems in a long-term field experiment was evaluated. The populations efficiencies were evaluated by in vivo tests that assessed the control of soybean damping-off caused by Rhizoctonia solani, plant height and soil colonization with the antagonist. In vitro tests, such as dual culture and assessment of volatile and non-volatile compounds, were conducted to study the mode of action of the populations. Some native Trichoderma populations were as efficient as those from a commercial product in all tests. Compared to conidial suspension, Trichoderma spp. inoculated through oat grains promoted a greater damping-off control, higher plants and more colony-forming units per gram of soil after 3 months of application. Native populations performed equally well or even better than the commercial strain, and the use of a substrate that supports the Trichoderma growth was more efficient than the conidial suspension method.

RESUMO: Podridão parda é a doença mais importante de pêssegos no Brasil. O objetivo deste estudo foi comparar os componentes monocíclicos da podridão parda de isolados brasileiros de M. fructicola e M. laxa, devido à detecção de M. laxa em uma área de produção de São Paulo. A germinação de conídios e esporulação do patógeno foram avaliadas in vitro sob uma faixa de temperatura de 5-35oC e duração do molhamento de 6-48h. Os períodos de incubação e de latência, a incidência da doença, a severidade da doença e a reprodução do patógeno em frutos de pêssego foram avaliados em 10, 15, 20, 25 e 30ºC e duração de molhamento de 6, 12 e 24h. Seis dos sete parâmetros de uma função beta generalizada para germinação de conídios de M. fructicola e M. laxa foram semelhantes. Apenas o parâmetro de forma foi mais alto para M. fructicola indicando que a gama de temperaturas e períodos de molhamento favoráveis para germinação é maior para M. laxa do que para M. fructicola. A temperatura ideal para o desenvolvimento de podridão parda causada por M. fructicola foi 24,5oC e para Monilinia laxa foi 19,8oC. A 10oC lesões de M. laxa produziram mais conídios que as de M. fructicola, e o inverso ocorreu a 30oC. A temperatura máxima estimada para o desenvolvimento de lesões também foi maior para M. fructicola do que para M. laxa. M. fructicola é favorecido por um clima mais quente do que M. laxa e a presença e impacto deste patógeno no Brazil deve ser acompanhado em especial no estados do sul do país.

ABSTRACT: Brown rot is the most important disease of peaches in Brazil. The objective of this study was to compare the brown rot monocyclic components from Monilinia fructicola and M. laxa isolates from Brazil on peaches, due to the detection of M. laxa in the São Paulo production area. Conidia germination and pathogen sporulation were assessed in vitro under a temperature range of 5-35oC and wetness duration of 6-48h. Incubation and latent periods, disease incidence, disease severity and pathogen reproduction on peach fruit were evaluated under 10, 15, 20, 25 and 30oC and wetness duration of 6, 12 and 24h. Six of seven parameters of a generalised beta function fitted to conidia germination of M. fructicola and M. laxa were similar. Only the shape parameter was higher for M. fructicola indicating that the range of temperatures and wetness periods favourable for germination is wider for M. laxa than for M. fructicola. The optimum temperature for brown rot development caused by M. fructicola was 24.5oC and for. Monilinia laxa was 19.8oC. At 10oC M. laxa lesions produced more conidia than M. fructicola, and the opposite occurred at 30oC. The estimated maximum temperature for lesion development was also higher for M. fructicola than for M. laxa. M. fructicola is favored by warmer weather than M. laxa and the presence and impact of this specie in Brazil must be investigated especially in the South states.

RESUMO: Várias doenças podem estar associadas com figos, mas recentemente uma podridão dos frutos foi observada em frutos verdes. O objetivo deste estudo foi determinar a patogenicidade de Botrytis sp., quantificar o período de incubação (PI) e o período de latência (PL), verificar a temperatura ótima para o crescimento micelial e identificar as diferentes espécies de Botrytis sp. isoladas a partir de frutos imaturos de figo. Botrytis sp. isolado a partir de figos provou ser patogênico em frutos imaturos com e sem ferimento na superfície dos frutos e no ostíolo. O PI foi de 3 dias em frutos com ferimento e 5 dias em frutos inoculados no ostíolo e sem ferimento. O PL foi de 6 dias em todos os tratamentos. A temperatura ótima de crescimento micelial foi18°C. A partir de sequências de um segmento que compreende a região de ITS do DNA ribossomal, concluiu-se que os isolados são Botrytis cinerea.

ABSTRACT: Several diseases can be associated with figs but recently a fruit rot was observed in green fruit. The purpose of this study was to determine the pathogenicity of Botrytis sp., to quantify incubation period (IP) and latent period (LP), to verify the optimum temperature for mycelial growth, and to identify the different species of Botrytis sp. isolated from immature figs. Botrytis sp. isolated from figs proved to be pathogenic to immature fruit with and without wounding the fruit surface and ostiole. The IP period was 3 days on fruit with wounds and 5 days on fruit inoculated within the ostiole (without wound). The LP was 6 days in all treatments. The optimum temperature for mycelial growth was 18°C. Inferred from sequences of a segment comprising the ITS region of ribosomal DNA concluded that the isolates are Botrytis cinerea.

RESUMO: O míldio da soja é disseminado em todo mundo. Entretanto, o dano que ele causa não tem sido estudado no Brasil. O objetivo deste trabalho foi avaliar quais componentes de rendimento da soja são afetados por essa doença e determinar o coeficiente de dano. Dois experimentos foram conduzidos, um em Castro (2006/07) e outro em Ponta Grossa (2007/08), no Estado do Paraná, Brasil. O delineamento experimental foi de blocos ao acaso com (i) seis tratamentos e cinco repetições para os experimentos de campo, safras 2006/07, e (ii) oito tratamentos e quatro repetições para 2007/08. Foram aplicados fosfito de potássio (750g ia ha-1), propamocarb + fenamidona (900g ia ha-1) e mancozeb (2,400g ia ha-1). Em todos os tratamentos, a severidade máxima da infecção pelo míldio ocorreu no estádio R5.3 e a porcentagem de severidade variou entre 0 e 43%. O gradiente da doença foi obtido apenas na segunda safra. Equações de danos foram geradas para o peso de grãos e produtividade. O número de grãos por vagem e o número de vagens por planta não foram afetados pelo míldio mas o peso de 1000 sementes por planta foi reduzido linearmente com o aumento da severidade do míldio.

ABSTRACT: Downy mildew is widespread throughout the world. However, the damage that it causes has not been studied in Brazil yet. The objective of this work was to evaluate which components of soybean yield are affected by downy mildew and to determine the coefficient of damage. Two field experiments were conducted in Castro (2006/07) and Ponta Grossa (2007/08) in the state of Parana, Brazil. The experimental design consisted of completely randomized blocks of (i) six treatments and five replications for the 2006/07 and (ii) eight treatments and four replications for the 2007/08 field experiments. Potassium phosphite (750g a.i. ha-1), propamocarb + fenamidone (900g a.i. ha-1) and mancozeb (2400g a.i. ha-1) were applied. In all of the treatments, the maximum severity of downy mildew infection occurred at growth stage R5.3, and the percentage of severity ranged between 0 and 43%. The disease gradient was obtained only on the second season. Equations of damage were generated for the yield and grain weight. The number of grains per pod and the number of pods per plant were not affected by downy mildew but, the weight of 1000 seeds per plant was reduced linearly with increasing of mildew severity.

RESUMO Frutíferas de clima temperado, frequentemente apresentam deficiência e desuniformidade na brotação e floração, devido ao baixo número de horas de frio para a ocorrência da dormência e de sua profundidade. O objetivo deste trabalho foi determinar a intensidade da dormência de gemas de cultivares de pessegueiro e avaliar a eficiência do teste do tetrazólio para avaliar a dormência comparando com o teste biológico. Os ramos das cultivares Aurora 1, Chimarrita, Chiripá, Coral, Eldorado, Granada, Leonense, Maciel, Marli, Premier e Vanguarda, foram coletados entre maio e agosto de 2008 em dois locais: Curitiba e Lapa. A avaliação da dormência foi realizada pelo teste biológico de estacas de nós isolados por meio dos parâmetros: tempo médio para brotação, velocidade de brotação, taxa final de brotação e taxa de brotações vigorosas. Para o teste do tetrazólio utilizou-se 300 mg de gemas e as leituras de intensidade de cor foram obtidas em espectrofotômetro. As cultivares de pessegueiro avaliadas diferem quanto a intensidade de dormência no final do outono, sendo a endodormência mais intensa nas cultivares Chiripá, Leonense e Eldorado e mais fraca nas cultivares Aurora 1 e Maciel. O teste do tetrazólio foi eficiente para estimar a intensidade de dormência das gemas de pessegueiro onde a ocorrência de frio foi adequada para a instalação da endodormência. No local com menor ocorrência de frio (Curitiba), o teste do tetrazólio não simulou com sucesso os resultados do teste biológico.

ABSTRACT Temperate climate fruit trees often exhibit uneven budding and flowering, due to the low number of chilling hours that determine the occurrence of dormancy and its depth. The objective of this study was to determine the depth of bud dormancy in peach tree cultivars and evaluate the efficiency of the tetrazolium test for dormancy and comparing with biological test. Branches of the cultivars Aurora 1, Chimarrita, Chiripá, Coral, Eldorado, Granada, Leonense, Maciel, Marli, Premier, and Vanguard were collected between May and August 2008 at two locations: Curitiba and Lapa. The evaluation of dormancy was performed using a biological test of single node cuttings through the parameters: average time for bud burst, velocity of bud burst, final rate of bud burst and rate of vigorous bud burst. For the tetrazolium test, 300 mg of buds was used and the color intensity readings were obtained using a spectrophotometer. The peach tree cultivars evaluated differ in the intensity of dormancy in late fall. The most intense endodormancy cultivars found were: Chiripá, Leonense and Eldorado cultivars, and the weaker cultivars found were: Aurora 1 and Maciel. The tetrazolium test was efficient at estimating the intensity of dormancy in peach trees when the occurrence of cold was suitable for installation endodormancy. At a location with the lowest occurrence of cold (Curitiba), the tetrazolium test did not simulated successfully the biological test results.