AGRESSIVENESS AND BIOCONTROL OF Rosellinia bunodes IN POPLAR

The Rosellinia root rot, caused by the fungus Rosellinia bunodes, has gained prominence due to the incidence in commercial plantations of forest species, such as poplar. Due to the absence of phytosanitary products registered for this crop in Brazil, cultural control, often inefficient, becomes the only option for the control of this disease. In the search for solutions to this problem, biological control meets the needs of implementing a more sustainable system. The objective of this work was to evaluate the aggressiveness of R. bunodes isolates in poplar and the antagonistic capacity in vitro and in vivo of Trichoderma spp. in control of this phytopathogen. For the aggressiveness test, healthy poplar seedlings were planted on substrate inoculated with nine R. bunodes isolates. The tests of antagonism in direct confrontation, production of volatile and non-volatile compounds were performed among 30 isolates of Trichoderma spp. and R. bunodes isolate R2. In the in vivo test, the treatments consisted of different planting dates of the seedlings infested with the antagonist fungus and the phytopathogen. R. bunodes isolates R2, R3, R3A, R6 and R8 were more aggressive than the others. From 30 isolates of Trichoderma spp., 12 may be considered as potential biocontrol agents due to the high competitive capacity and suppression of mycelial growth of R. bunodes. The longer exposure time between the pathogen and the antagonist on the substrate decreased the incidence of Rosellinia root rot in poplar

IMPACTO DA MANCHA FOLIAR CAUSADA POR Cylindrocladium candelabrum EM PLANTIOS JOVENS DE Eucalyptus benthamii EM RIO NEGRINHO – SC

http://dx.doi.org/10.5902/1980509818448Eucalyptus benthamii is one of the planted forest species in Southern Brazil due to its frost resistance. The main disease in commercial plantations is the leaf spot caused by Cylindrocladium candelabrum. The objective of this work was to evaluate incidence and severity of this disease in Eucalyptus benthamii plantations, in Rio Negrinho,  SC state. The survey was performed in three plantations (4, 8 and 18 months-old), quantifying the number of diseased trees and evaluating the severity by using a diagrammatic scale varying from 0 (no spot and shedding of leaves) to 5 (more than 75 % of defoliation). Four evaluations were done from July/2011 to June/2013. The average incidence of leaf spot on trees varied from 2.6 to 43.8 %, depending upon the age, while the average severity varied from 1.2 to 2.8, with low severity in trees of 4 and 8 months-old. It was verified increase on disease severity increasing tree age and the direct relationship between disease intensity and precipitation volume as well as between severity and tree height. The relationship between the incidence of plants with leaf spot varied according to tree heights.http://dx.doi.org/10.5902/1980509818448Eucalyptus benthamii é uma das espécies florestais plantada na região Sul do Brasil devido à sua resistência à geada. A principal doença em plantios comerciais é a mancha foliar causada por Cylindrocladium candelabrum. O objetivo deste trabalho foi avaliar a incidência e a severidade da doença em plantios de Eucalyptus benthamii, localizados em Rio Negrinho - SC. O levantamento foi realizado em três plantios (quatro, oito e 18 meses de idade), quantificando-se a incidência pelo percentual de plantas doentes e a severidade com uma escala diagramática que variou de 0 (sem mancha e desfolha) a 5 (mais de 75 % de desfolha). Quatro avaliações foram feitas no período de julho/2011 a junho/2013. A incidência média de árvores com a mancha foliar variou de 2,6 até 43,8 % das árvores, dependendo da idade, enquanto que a severidade média variou de 1,2 a 2,9, com menor severidade nas árvores de quatro e oito meses de idade. Verificaram-se relações diretas entre a intensidade da doença e o volume de precipitação pluviométrica, bem como entre severidade e altura da árvore. A relação entre incidência de plantas com mancha foliar variou de acordo com a altura das árvores

QUALIDADE SANITÁRIA E FISIOLÓGICA DE SEMENTES DE ARAUCÁRIA DURANTE ARMAZENAMENTO

Araucaria angustifolia is a species of ecological and social-economic importance in the southern Brazil region, but it is at risk of extinction. Its seeds are classified as recalcitrant, requiring storage under controlled temperature and humidity to obtain greater longevity. Another aspect is the seed health quality, which is impaired by high seed moisture content that causes fungus proliferation and may reduce germination and seedling quality. The objective of this study was to evaluate the physiological and sanitary quality of araucaria seeds treated with 0.5, 1 and 3 % of sodium hypochlorite (NaClO) and stored at different periods (2, 4, 6, 8 and 12 months). The seed quality was evaluated by germination, vigor and seed health tests. The disinfection of seeds, regardless of the concentration used, temporarily delayed the seed germinations, but did not negatively affect seedling emergence. After 12 months of storage, the seeds showed infection by Schizophyllum commune, which caused the reduction of the germination. The seeds treated with NaClO showed lower fungal incidence, especially Schizophyllum commune, ensuring the seed health quality during storage for 12 months. The treatment with NaClO positively favors the physiological quality of Araucaria seeds that will be stored for a period exceeding four months.Araucaria angustifolia é uma espécie de importância ecológica e socioeconômica na região Sul do Brasil, porém, em risco de extinção. Sua semente é classificada como recalcitrante, necessitando armazenamento sob temperatura e umidade relativa controladas para maior longevidade. Outro aspecto refere-se à qualidade sanitária das sementes, a qual é prejudicada pelo elevado teor de água que causa a proliferação de fungos, os quais podem reduzir a germinação. Este trabalho teve como objetivo avaliar a qualidade sanitária e fisiológica de sementes de araucária desinfestadas com solução de hipoclorito de sódio (NaClO) a 0,5; 1 e 3 % e submetidas a diferentes períodos de armazenamento (2, 4, 6, 8 e 12 meses). A qualidade das sementes foi avaliada pelos testes de germinação, vigor e sanidade. A desinfestação das sementes, independentemente da concentração utilizada, retardou temporariamente a germinação das mesmas, porém, não afetou negativamente a emergência das plântulas. Após 12 meses de armazenamento, verificou-se a infecção das sementes por Schizophyllum commune, o que causou a redução da germinação. As sementes tratadas com NaClO apresentaram menor incidência de fungos, especialmente Schizophyllum commune, garantindo a qualidade sanitária das mesmas durante o armazenamento por 12 meses. O tratamento com NaClO favorece positivamente a qualidade fisiológica das sementes de araucária que serão armazenadas por período superior a 4 meses

Evaluation methodology of the aggressiveness of isolated of Sphaeropsis sapinea on Pinus taeda

Sphaeropsis sapinea é conhecido como importante patógeno em Pinus, causando seca de ponteiros e morte de árvores em plantios comerciais. No Brasil, o primeiro relato da ação de S. sapinea ocorreu na década de 1940, durante introdução de Pinus radiata no estado de São Paulo, dizimando totalmente os plantios. Com o objetivo de selecionar material genético resistente a essa doença no Brasil, desenvolveu-se uma metodologia para avaliar a agressividade de isolados de S. sapinea em frutos de maçã e Pinus taeda. Três ambientes (estufas com diferentes regimes de irrigação), dois métodos de inoculação (com e sem injúria) e três métodos de reisolamento do fungo (meio BDA, câmara úmida em saco plástico e em gerbox úmido) foram testados. Resultados mostraram diferenças significativas (p<0,05)na agressividade dos isolados em frutos de maçã e em mudas de P. taeda. O melhor método de reisolamento foi a câmara úmida e o melhor ambiente para a incubação de mudas de P. taeda foi em estufa coberta com lona plástica, com duas aspersões diárias de 4 minutos. Outro resultado foi que injúria é necessária para inoculação de S. sapinea. Os resultados da caracterização mostraram diferenças significativas na agressividade e diversidade genética do patógeno em todos os hospedeiros testados.Palavras-chave: Fungo; inoculação; melhoramento genético; Pinus.AbstractEvaluation methodology of the aggressiveness of isolated of Sphaeropsis sapinea on Pinus taeda. Sphaeropsis sapineais known as an important pathogen of Pinus, causing tip blight and death of trees in commercial plantings. In Brazil, the first report of this disease was done in the 1940s, during introduction of Pinus radiata in São Paulo State, when these plantations were destroyed by S sapinea. In order to select material resistant to such disease in Brazil,a methodology was developed to evaluate aggressiveness in S. sapinea isolates on apple fruits and Pinus taeda. Three environments (greenhouse with different regimes of irrigation), two inoculation methods (with and without injury) and three methods of re-isolation of fungus (PDA medium, moist chamber in plastic bags and moist gerbox) had been tested. Results pointed to significant differences (p < 0,05) on aggressiveness in apple fruit and P. taeda seedlings. The better method to re-isolate was moist chamber in plastic bags and the better environment to incubate inoculated seedlings was greenhouse with two diary aspersion of four minutes. Other result was that injury is necessary for a good inoculation of S. sapinea. The characterization results have presented significant differences in relation to aggressiveness and genetic diversity of the pathogen in all tested hosts.Keywords: Breeding; fungus; inoculation; Pinus.Sphaeropsis sapineais known as an important pathogen of Pinus, causing tip blight and death of trees in commercial plantings. In Brazil, the first report of this disease was done in the 1940s, during introduction of Pinus radiata in São Paulo State, when these plantations were destroyed by S sapinea. In order to select material resistant to such disease in Brazil,a methodology was developed to evaluate aggressiveness in S. sapinea isolates on apple fruits and Pinus taeda. Three environments (greenhouse with different regimes of irrigation), two inoculation methods (with and without injury) and three methods of re-isolation of fungus (PDA medium, moist chamber in plastic bags and moist gerbox) had been tested. Results pointed to significant differences (p < 0,05) on aggressiveness in apple fruit and P. taeda seedlings. The better method to re-isolate was moist chamber in plastic bags and the better environment to incubate inoculated seedlings was greenhouse with two diary aspersion of four minutes. Other result was that injury is necessary for a good inoculation of S. sapinea. The characterization results have presented significant differences in relation to aggressiveness and genetic diversity of the pathogen in all tested hosts

MÉTODOS DE DETECÇÃO, TRANSMISSÃO E PATOGENICIDADE DE Fusarium spp. EM SEMENTES DE Pinus taeda

The root rots (RR), caused by the Fusarium spp., causes loss of seedling in the nursery that show, initially, discoloration of the needles to a yellowish-green tone followed by apical curvature, wilt and the consequent death of the seedling. The objectives of this work were to: a) define the most appropriate and efficient method to detect Fusarium spp. in Pinus taeda seeds; b) verify if there is transmission of Fusarium spp. from seeds to Pinus taeda seedlings; c) develop a descriptive scale to evaluate the severity of the RR in Pinus taeda seedlings; d) evaluate the pathogenicity, aggressiveness and area under the disease progress curve (AUDPC) of isolated Fusarium subglutinans. For detection three treatments were applied to six lots of Pinus taeda seeds, being four repetitions of 25 seeds: blotter test, paper card and selective medium. The transmission was evaluated in seeds from six lots of Pinus taeda during 60 days counting the percentage of emerged plantlet (EP), non-germinated seeds (NGS) and from NGS seeds with Fusarium spp. A descriptive scale of grades was developed to evaluate the severity of RR in Pinus taeda seedlings. The severity and the incidence of the illness were evaluated at 7, 14, 21 and 28 days after the inoculation from Pinus taeda seedlings of six months of age. The pathogenicity, severity and incidence of twelve isolated Fusarium subglutinans obtained in the detection test. To test for pathogenicity and aggressiveness 13 treatments with 15 replications were applied. The most sensitive detection method to detect Fusarium spp. on Pinus taeda seeds was the selective medium; transmission was not observed of Fusarium spp. from seeds to the seedlings; the descriptive scale allowed evaluating the progression of RR symptoms; nine isolated of Fusarium spp. were found to be pathogenic to Pinus taeda seedlings, reproducing typical symptoms of RR, being isolated L3R2, the most aggressive and that exhibited higher AUDPC.A podridão-de-raiz (PR), causada por Fusarium spp., ocasiona perdas de plântulas no viveiro que apresentam, inicialmente, descoloração das acículas para tom verde-amarelado seguida de curvatura apical, murcha e consequente morte da muda. Os objetivos deste trabalho foram: a) determinar o método adequado e eficiente para detecção de Fusarium spp. nas sementes de Pinus taeda; b) verificar se há transmissão de Fusarium spp. das sementes para as plântulas de Pinus taeda; c) desenvolver uma escala descritiva para avaliar a severidade da PR em mudas de Pinus taeda; d) avaliar a patogenicidade, agressividade e área abaixo da curva de progresso da doença (AACPD) de isolados de Fusarium spp. Para detecção foram aplicados três tratamentos em seis lotes de sementes de Pinus taeda, sendo quatro repetições de 25 sementes: blotter test, papel-cartão e meio seletivo. A transmissão foi avaliada em sementes de seis lotes de Pinus taeda durante 60 dias contabilizando-se a percentagem de plântulas emergidas (PE), sementes não germinadas (SNG) e de SNG com Fusarium spp. Uma escala descritiva de notas foi desenvolvida para avaliar a severidade de PR em mudas de Pinus taeda. A severidade e a incidência da doença foram avaliadas aos 7, 14, 21 e 28 dias após a inoculação das mudas de Pinus taeda de seis meses de idade. Foi avaliada a patogenicidade, a severidade e a incidência de doze isolados de Fusarium spp. obtidos no teste de detecção Para o teste de patogenicidade e agressividade foram 13 tratamentos com 15 repetições. O método de detecção mais sensível ao detectar Fusarium spp. em sementes de Pinus taeda foi o meio seletivo. Não foi observada transmissão de Fusarium spp. das sementes para as plântulas, no entanto, Fusarium spp. causou apodrecimento de sementes na fase de germinação; a escala descritiva permitiu a avaliação da progressão dos sintomas da doença PR; nove isolados de Fusarium spp.  mostraram-se patogênicos a mudas de Pinus taeda, reproduzindo sintomas típicos da PR, sendo o isolado L3R2 o mais agressivo e o que exibiu maior AACPD

POLYPHENOLS IN YERBA MATE SEEDS: POTENTIAL INHIBITORS OF GERMINATION

Due to its economic, social, and ecological potentials, yerba mate can be a source of employment and income in the southern region of Brazil. The objectives of the present study was to (1) quantify the total polyphenols in fresh yerba mate seeds (FS), seeds dehydrated for 70 d (SD), and seeds stratified in sand for 180 d (SS); (2) evaluate the potential germination and growth inhibitory effects of water, ethanol + water (1:1), and ethanol (99%) extracts of yerba seeds (FS, SD, and SS) using lettuce seedlings; and (3) verify the presence of polyphenols in fresh seeds of yerba mate through histochemical methods. In the bioassay, extracts of yerba mate seeds were used in the germination of lettuce seeds. For the histochemical analysis, sections of yerba mate seeds were stained with specific dyes. The results revealed that yerba mate fresh seeds contain higher concentration of phenolic compounds, which decreased in dehydrated seeds, and almost no phenolic compound was observed in stratified seeds. The bioassay results showed that the polyphenols present in the extracts of yerba mate seeds resulted in phytotoxic effect on the roots of lettuce seedlings. The histochemical observations revealed the presence of “lignified rough barrier” and phenolic compounds between the endocarp and endosperm of the yerba mate seeds.Due to its economic, social, and ecological potentials, yerba mate can be a source of employment and income in the southern region of Brazil. The objectives of the present study was to (1) quantify the total polyphenols in fresh yerba mate seeds (FS), seeds dehydrated for 70 d (SD), and seeds stratified in sand for 180 d (SS); (2) evaluate the potential germination and growth inhibitory effects of water, ethanol + water (1:1), and ethanol (99%) extracts of yerba seeds (FS, SD, and SS) using lettuce seedlings; and (3) verify the presence of polyphenols in fresh seeds of yerba mate through histochemical methods. In the bioassay, extracts of yerba mate seeds were used in the germination of lettuce seeds. For the histochemical analysis, sections of yerba mate seeds were stained with specific dyes. The results revealed that yerba mate fresh seeds contain higher concentration of phenolic compounds, which decreased in dehydrated seeds, and almost no phenolic compound was observed in stratified seeds. The bioassay results showed that the polyphenols present in the extracts of yerba mate seeds resulted in phytotoxic effect on the roots of lettuce seedlings. The histochemical observations revealed the presence of “lignified rough barrier” and phenolic compounds between the endocarp and endosperm of the yerba mate seed

In vitro selection of endophytes for biological control of Botrytis cinerea in Eucalyptus benthamii

   O Eucalyptus benthamii é uma das principais espécies de eucalipto plantadas na região Sul do Brasil, por sua resistência a geadas e por seu uso na produção florestal de madeira para fins energéticos. Na produção de mudas, uma das principais doenças ocorrentes em viveiros é o mofo-cinzento, causado pelo fungo Botrytis cinerea. Uma das alternativas para o controle dessa doença é o controle biológico com fungos endofíticos, os quais podem competir com os patógenos foliares de mudas de eucalipto. O objetivo deste trabalho foi isolar os fungos endofíticos provenientes de mudas de E. benthamii, identificá-los e selecioná-los para o controle de B. cinerea. Eles foram isolados do interior de tecidos vegetais desinfectados, identificados de acordo com critérios macro e micromorfológicos e classificados a partir de testes de controle biológico in vitro. Os resultados evidenciaram o potencial antagonista dos fungos Aspergillus sp., Penicillium sp. e Trichoderma sp. Nenhum desses fungos causou lesões em mudas de E. benthamii.Palavras-chave: Mofo-cinzento; eucalipto; viveiro.AbstractIn vitro selection of endophytes for biological control of Botrytis cinerea in Eucalyptus benthamii. Eucalyptus benthamii is one of the main eucalypt species planted in Southern Brazil, due to its resistance to frost and its use in the production of forest wood for energy purposes. During the production of seedlings, the main disease occurring in forest nurseries is gray-mold caused by the fungus Botrytis cinerea. One alternative for control this disease is biological control with fungal endophytes, which can compete with the foliar pathogens of eucalypt seedlings. The objective of this study was to isolate endophytic fungi from seedlings of Eucalyptus benthamii, identify and select them for B. cinerea control. These were isolated from the interior of disinfected plant tissues, identified according to macro and micromorphological criteria, and based on tests of biological control in vitro. The results revealed the potential antagonist of Aspergillus sp., Penicillium sp. and Trichoderma sp. No fungi caused lesions in E. benthamii seedlings.Keywords: Gray-mold; eucalypt; nursery.    AbstractEucalyptus benthamii is one of the main eucalypt species planted in Southern Brazil, due to its resistance to frost and its use in the production of forest wood for energy purposes. During the production of seedlings, the main disease occurring in forest nurseries is gray-mold caused by the fungus Botrytis cinerea. One alternative for control this disease is biological control with fungal endophytes, which can compete with the foliar pathogens of eucalypt seedlings. The objective of this study was to isolate endophytic fungi from seedlings of Eucalyptus benthamii, identify and select them for B. cinerea control. These were isolated from the interior of disinfected plant tissues, identified according to macro and micromorphological criteria, and based on tests of biological control in vitro. The results revealed the potential antagonist of Aspergillus sp., Penicillium sp. and Trichoderma sp. No fungi caused lesions in E. benthamii seedlings.Keywords: Gray-mold; eucalypt; nursery

Identificação e caracterização de espécies de Pestalotiopsis patogênicas à nogueira‑pecã no Brasil

The objective of this work was to characterize and cluster isolates of Pestalotiopsis species and to identify those that are pathogenic to pecan, based on morphological and molecular characters. Pestalotiopsis spp. isolates were identified by sequencing the internal transcribed spacer (ITS) and β‑tubulin regions. Identification methods were compared to indicate the key morphological characters for species characterization. Thirteen isolates were used for the pathogenicity tests. Morphological characterization was performed using the following variables: mycelial growth rate, sporulation, colony pigmentation, and conidial length and width. Ten pathogenic isolates were identified, three as Pestalotiopsis clavispora and three as P. cocculi. The other isolates remained as an undefined species. The morphological characters were efficient for an initial separation of the isolates, which were grouped according to differences at species level, mainly colony diameter, which was identified as an important morphological describer. Beta‑tubulin gene sequencing was less informative than the ITS region sequencing for species identification.O objetivo deste trabalho foi caracterizar e agrupar isolados de espécies de Pestalotiopsis e identificar aquelas patogênicas à nogueira‑pecã, com base em caracteres morfológicos e moleculares. Os isolados de Pestalotiopsis spp. foram identificados por meio do sequenciamento das regiões internal transcribed spacer (ITS) e β‑tubulina. Os métodos de identificação foram comparados, para indicar os caracteres morfológicos chave para a caracterização das espécies. Treze isolados foram utilizados para os testes de patogenicidade. A caracterização morfológica foi realizada com a utilização das seguintes variáveis: taxa de crescimento micelial, esporulação, pigmentação das colônias, comprimento e largura de conídios. Dez isolados patogênicos foram identificados, três como Pestalotiopsis clavispora e três como P. cocculi. Os outros isolados permaneceram como espécie não definida. Os caracteres morfológicos foram eficientes na separação inicial dos isolados, os quais foram agrupados por diferenças quanto à espécie, principalmente o diâmetro das colônias, identificado como um importante descritor morfológico. O sequenciamento do gene da β‑tubulina foi menos informativo do que o sequenciamento da região ITS para a identificação de espécies

FUNGOS ASSOCIADOS À MANCHA FOLIAR EM Eucalyptus benthamii Maiden et Cambage NA REGIÃO SUL DO BRASIL

Um dos fatores mais importantes que influenciam no sucesso de plantios florestais é a fitossanidade dos mesmos. Doenças foliares causadas por fungos têm sido frequentemente constatadas em plantios de eucalipto em diversas regiões do Brasil. O objetivo deste trabalho foi avaliar os sintomas e identificar os fungos causadores de mancha foliar em testes de procedência e progênies de Eucalyptus benthamii em três locais na região sul do Brasil. A avaliação foi realizada em São Mateus do Sul (PR), Mafra (SC) e Porto União (SC) aos 10, 16 e 27 meses de idade dos plantios. Foi verificada a frequência e os sintomas dos fungos que ocasionaram a doença. Os gêneros Cylindrocladium e Pestalotiopsis foram constatados em todas as avaliações nos três locais de estudo. Por meio dos fungos identificados, Cylindrocladium sp. foi o de maior frequência e é tido como o principal agente causador da mancha foliar nas populações de E. benthamii avaliadas