Resistance to diseases of sour, sweet and wild passion fruit genotypes

The cultivation of passion fruit is important for Brazil, since the country is currently the largest producer and consumer of fruit in the world. However, the fields of passion fruit still face important problems due to the incidence and severity of diseases in the field. Thus, the present study aimed to assess resistance to bacterial and fungal diseases in 13 genotypes of sour, sweet and wild passion fruit, in field conditions in the Distrito Federal, Brazil. For this, a field experiment was installed in a randomized block design, with four replications and 13 treatments (genotypes). The characteristics of incidence, severity and degree of resistance for bacteriosis, septoriosis, scab and anthracnose diseases were evaluated in 5 fruits per plot of each genotype. Genetic parameters of the evaluated traits were also estimated. High heritability values and CVg/Cve ratio were observed for most of the evaluated characteristics. The genotypes presented mean values of incidence and severity of bacteriosis, septoriosis, scab and anthracnose different among them, and the one that presented the best results in the degree of resistance for all diseases was F1 (MAR20 # 24 x ECL7 P1 R4).

A peptidogalactomannan isolated from Cladosporium herbarum induces defense-related genes in BY-2 tobacco cells.

Cladosporium herbarum is a plant pathogen associated with passion fruit scab and mild diseases in pea and soybean. In this study, a peptidogalactomannan (pGM) of C. herbarum mycelium was isolated and structurally characterized, and its role in plant-fungus interactions was evaluated. C. herbarum pGM is composed of carbohydrates (76%) and contains mannose, galactose and glucose as its main monosaccharides (molar ratio, 52:36:12). Methylation and 13C-nuclear magnetic resonance (13C-NMR) spectroscopy analysis have shown the presence of a main chain containing (1 → 6)-linked α-D-Manp residues, and ß-D-Galf residues are present as (1 → 5)-interlinked side chains. ß-Galactofuranose containing similar structures were characterized by our group in A. fumigatus, A. versicolor, A. flavus and C. resinae. Tobacco BY-2 cells were used as a model system to address the question of the role of C. herbarum pGM in cell viability and induction of the expression of plant defense-related genes. Native and partially acid hydrolyzed pGMs (lacking galactofuranosyl side-chain residues) were incubated with BY-2 cell suspensions at different concentrations. Cell viability drastically decreased after exposure to more than 400 µg ml-1 pGM; however no cell viability effect was observed after exposure to a partially acid hydrolyzed pGM. BY-2 cell contact with pGM strongly induce the expression of plant defense-related genes, such as phenylalanine ammonia lyase (PAL) and lipoxygenase (LOX), as well as the pathogen-related PR-1a, PR-2 and PR-3 genes, suggesting that pGM activates defense responses in tobacco cells. Interestingly, contact with partially hydrolyzed pGM also induced defense-related gene expression at earlier times than native pGM. These results show that the side chains of the (1 → 5)-linked ß-D-galactofuranosyl units from pGM play an important role in the first line fungus-plant interactions mediating plant responses against C. herbarum. In addition, it was observed that pGM and/or C. herbarum conidia are able to induced HR when in contact with tobacco leaves and in vitro plantlets roots, producing necrotic lesions and peroxidase and NO burst, respectively.

Composição química e atividade antifúngica do óleo essencial de poejo em diferentes estágios de desenvolvimento / Chemical composition and antifungal activity of pennyroyal essential oil in different stages of development

O objetivo deste estudo foi comparar o rendimento, a composição química e a atividade antifúngica do óleo essencial de Mentha pulegium (poejo) em diferentes estágios de desenvolvimento, cultivada sob condições controladas no sul do Brasil. A hidrodestilação de folhas frescas de M. pulegium, coletadas aos 60, 70 e 85 dias após o transplante, apresentou rendimento de óleo essencial de 0,17 %, 0,23 % e 0,17 %, respectivamente. Todas as amostras de óleo apresentaram atividade contra Cladosporium herbarum. Através das análises de cromatografia gasosa (GC) e GC/MS do óleo essencial, foram identificados onze constituintes, sete (mentona, isomentona, neoisomentol, pulegona, piperitona, 1.1- dimetoxi-2- nonino e piperitenona) comuns às três amostras, enquanto dois outros (mentofurano, mirtenal) foram detectados somente nas amostras da primeira e segunda coletas. A pulegona foi o principal constituinte nas duas primeiras amostras (26,65 %), seguida pela piperitenona (20,41; 12,60 %). A concentração de pulegona aumentou para 31,05 % na última coleta, porém o constituinte majoritário foi a piperitenona (36,32 %). Os resultados demonstraram que o óleo essencial de M. pulegium apresenta potencial como agente antifúngico e sua composição química depende do estágio de desenvolvimento da planta.(AU)

The aim of this study was to compare the yield, chemical composition and antifungal activity of the essential oil that is obtained from Mentha pulegium in different developmental stages and cultivated under controlled conditions in southern Brazil. The hydrodistillation of fresh leaves that were collected at 60, 70 and 85 days resulted inessential oil yields of 0.17 %, 0.23 % and 0.17 %, respectively. All of the essential oil samples showed antifungal activity against Cladosporium herbarum. The gas chromatograph (GC) and GC/MS analysis revealed eleven constituents: seven (pulegone, piperitenone, menthone, isomenthone, neoisomenthol, piperitone and 1.1-dimethoxy-2-nonyne) were common to three samples, while menthofuran and myrtenal were detected only in samples of the first and second stages. Pulegone was the main constituent of the essential oil samples from the first and second stages (26.65 %), followed by piperitenone (20.41; 12.60 %). The pulegone concentration increased to 31.05 % in the last collection, while the major constituent was piperitenone (36.32 %). In conclusion, the results demonstrated that M. pulegium essential oil presents potential as an antifungal agent, and its chemical composition depends on the stage of development during which it was extracted.(AU)

Composição química e atividade antifúngica do óleo essencial de poejo em diferentes estágios de desenvolvimento / Chemical composition and antifungal activity of pennyroyal essential oil in different stages of development

O objetivo deste estudo foi comparar o rendimento, a composição química e a atividade antifúngica do óleo essencial de Mentha pulegium (poejo) em diferentes estágios de desenvolvimento, cultivada sob condições controladas no sul do Brasil. A hidrodestilação de folhas frescas de M. pulegium, coletadas aos 60, 70 e 85 dias após o transplante, apresentou rendimento de óleo essencial de 0,17 %, 0,23 % e 0,17 %, respectivamente. Todas as amostras de óleo apresentaram atividade contra Cladosporium herbarum. Através das análises de cromatografia gasosa (GC) e GC/MS do óleo essencial, foram identificados onze constituintes, sete (mentona, isomentona, neoisomentol, pulegona, piperitona, 1.1- dimetoxi-2- nonino e piperitenona) comuns às três amostras, enquanto dois outros (mentofurano, mirtenal) foram detectados somente nas amostras da primeira e segunda coletas. A pulegona foi o principal constituinte nas duas primeiras amostras (26,65 %), seguida pela piperitenona (20,41; 12,60 %). A concentração de pulegona aumentou para 31,05 % na última coleta, porém o constituinte majoritário foi a piperitenona (36,32 %). Os resultados demonstraram que o óleo essencial de M. pulegium apresenta potencial como agente antifúngico e sua composição química depende do estágio de desenvolvimento da planta.

The aim of this study was to compare the yield, chemical composition and antifungal activity of the essential oil that is obtained from Mentha pulegium in different developmental stages and cultivated under controlled conditions in southern Brazil. The hydrodistillation of fresh leaves that were collected at 60, 70 and 85 days resulted inessential oil yields of 0.17 %, 0.23 % and 0.17 %, respectively. All of the essential oil samples showed antifungal activity against Cladosporium herbarum. The gas chromatograph (GC) and GC/MS analysis revealed eleven constituents: seven (pulegone, piperitenone, menthone, isomenthone, neoisomenthol, piperitone and 1.1-dimethoxy-2-nonyne) were common to three samples, while menthofuran and myrtenal were detected only in samples of the first and second stages. Pulegone was the main constituent of the essential oil samples from the first and second stages (26.65 %), followed by piperitenone (20.41; 12.60 %). The pulegone concentration increased to 31.05 % in the last collection, while the major constituent was piperitenone (36.32 %). In conclusion, the results demonstrated that M. pulegium essential oil presents potential as an antifungal agent, and its chemical composition depends on the stage of development during which it was extracted.

Iridoid glucoside and antifungal phenolic compounds from Spathodea campanulata roots / Iridóide glicosilado e derivados fenólicos antifúngicos isoladosdas raízes de Spathodea campanulata

The chemical study of Spathodea campanulata (Bignoniaceae) roots peels afforded an iridoid glucoside(ajugol) and two phenolic derivatives (p-hydroxy-benzoic acid and methyl p-hydroxy-benzoate). Thecompounds were characterized upon spectral data interpretation. Bioactivities of the constituents wereevaluated against fungus Cladosporium herbarum.

O estudo químico das cascas das raízes de Spathodea campanulata (Bignoniaceae) conduziu ao isolamentode um irióide glicosilado (ajugol) e dois derivados fenólicos (ácido p-hidroxi-benzóico e p-hidroxi-benzoato demetila). Os compostos foram identificados com base na interpretação dos seus dados espectrais. A atividadebiológica destes constituintes foi avaliada contra o fungo Cladosporium herbarum

Iridoid glucoside and antifungal phenolic compounds from Spathodea campanulata roots / Iridóide glicosilado e derivados fenólicos antifúngicos isolados das raízes de Spathodea campanulata

The chemical study of Spathodea campanulata (Bignoniaceae) roots peels afforded an iridoid glucoside (ajugol) and two phenolic derivatives (p-hydroxy-benzoic acid and methyl p-hydroxy-benzoate). The  compounds were characterized upon spectral data interpretation. Bioactivities of the constituents were evaluated against fungus Cladosporium herbarum.

 O estudo químico das cascas das raízes de Spathodea campanulata (Bignoniaceae) conduziu ao isolamento de um irióide glicosilado (ajugol) e dois derivados fenólicos (ácido p-hidroxi-benzóico e p-hidroxi-benzoato de metila). Os compostos foram identificados com base na interpretação dos seus dados espectrais. A atividade biológica destes constituintes foi avaliada contra o fungo Cladosporium herbarum.