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The evaluation of genetic diversity among the accessions of a germplasm collection results in information about promising materials suitable for breeding programs. Thus, the goal of this work was to characterize Capsicum baccatum accessions from different Brazilian regions, based on morphological, biochemical and molecular traits, aiming to support chili pepper breeding programs. The fruits were morphologically characterized based on fruit length, diameter, fresh mass and pericarp thickness, and biochemically analyzed for their content in ascorbic and phenolic acids, flavonoid and antioxidant activity by 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•) and ferric reducing antioxidant power (FRAP) assays. All phenotypic traits showed significant differences among the chili pepper accessions, indicating a wide variability. The fruits were also characterized using amplified fragment length polymorphism (AFLP) molecular markers. The combination of six AFLP primers resulted in 1117 bands, 1033 of which were polymorphic. Divergence between accessions was estimated by the Ward’s hierarchical agglomerative clustering method, resulting in three and two clusters for fruit phenotypic traits and molecular data, respectively. In Bayesian analysis, molecular data also clustered the accessions in two groups. There was no association between the phenotypic descriptors and AFLP markers, indicating that both characterizations are important to better understand the genetic variability. Furthermore, it was not possible to group the accessions solely based on their origin for neither phenotypic descriptors and AFLP markers. The accessions G1, G5, G6, and G20 showed interesting characteristics and can be used in breeding programs, aiming the development of Capsicum spp. cultivars with desirable morphological and biochemical traits.

Broccoli (Brassica oleracea var. italica) is one of the most important vegetables in the world and also shows important functional properties. The present study aimed to characterize 19 broccoli genotypes using biochemical traits (content of total phenolic compounds, total flavonoids and antioxidant activity) and AFLP (Amplified Fragment Length Polymorphism) molecular markers. The experiment was carried out in a greenhouse using a complete randomized block design with three replicates. The phenotypic data were subjected to analysis of variance (p≤0.05), Scott-Knott average clustering method (p≤0.05) and principal component analysis (PCA). Using molecular data, Ward’s hierarchical clustering, Bayesian clustering and principal coordinate analysis (PCoA) were performed. Molecular data showed genetic diversity among the genotypes (three groups), also a wide variability in the total phenolic compounds, total flavonoids content and antioxidant activity using FRAP method. HT3010, Hanabi and Bonanza genotypes showed desirable biochemical traits for the demanding functional food consumers, in addition to being promising genotypes to be exploited in plant breeding programs. RESUMO Brócolis (Brassica oleracea var. italica) é umas das principais hortaliças do mundo e apresenta importantes propriedades funcionais. O presente estudo teve como objetivo caracterizar 19 genótipos de brócolis por meio de caracteres bioquímicos (teor de compostos fenólicos totais, flavonoides totais e atividade antioxidante) e marcadores moleculares do tipo AFLP (Amplified Fragment Length Polymorphism). O experimento foi realizado em casa de vegetação usando delineamento em blocos completos ao acaso com três repetições. Os dados fenotípicos foram submetidos à análise de variância (p≤0,05), agrupamento de média de Scott-Knott (p≤0,05) e análise de componentes principais (PCA). A partir dos dados moleculares, foram realizados os agrupamentos hierárquicos de Ward, agrupamento Bayesiano e análise de coordenadas principais (PCoA). Os dados moleculares indicaram diversidade genética entre os genótipos (três grupos), além de ampla variabilidade para o teor de compostos fenólicos totais, flavonoides totais e atividade antioxidante pelo método FRAP. Os genótipos HT3010, Hanabi e Bonanza apresentam características bioquímicas desejáveis aos consumidores exigentes em alimentos funcionais, além de serem genótipos promissores para serem explorados em programas de melhoramento da cultura.

Anthracnose, caused by Colletotrichum spp., is one of the most common diseases affecting sweet pepper and chilli pepper production worldwide, especially in tropical and subtropical zones. This disease results in severe fruit damage both pre‐ and postharvest. The development of resistant cultivars is the most effective strategy for disease control, which requires knowing the genetic basis of resistance. In this study, we analysed the inheritance of resistance of Capsicum annuum to Colletotrichum scovillei at two fruit development stages. The ripe and unripe fruits were inoculated by conidia suspension, and anthracnose severity was evaluated for 8 days using a score scale. It was found that the inheritance of resistance has independent expression in ripe and unripe fruits. In both cases, two main genes are responsible for resistance with polygenic effects. Genetic control, with a quantitative aspect, is more affected by dominance than the additive effects, in both fruit development stages of C. annuum.

Anthracnose is a disease caused by Colletotrichum spp., one of the world’s most damaging sweet and chili pepper pathogens, especially in tropical and subtropical regions. In the state of Rio de Janeiro, anthracnose is one of the main obstacles for pepper crops. However, to date no research has focused on the identification and characterization of the pathogen, which is fundamental to understand the scope of the disease in the state. Thus, the correct identification of the fungal species and pathogenicity studies can provide important support for disease management and control, apart from identifying possible resistance sources for exploitation in peppers breeding programs. In this study, 11 Colletotrichum isolates were collected from peppers with typical symptoms in the Rio de Janeiro state. These isolates were characterized based on morpho-cultural characteristics and sequencing data from five regions (ITS, ACT, CAL, β-TUB and GAPDH), and the genetic variability was estimated by AFLP markers. Simultaneously, microscopy images of the colonization by the fungal species on unripe Capsicum annuum fruits were taken. Pathogenicity was tested and resistance sources were sought by means of infection of ripe and unripe fruits of 50 Capsicum baccatum accessions. The resulting data showed that all isolates belong to Colletotrichum scovillei specie. About the pathogenicity of Capsicum baccatum, differentiated, stage-specific responses, with higher resistance of ripe fruits were recorded. In addition, four possible sources of Colletotrichum scovillei resistance were detected among the tested accessions. The combination of these data can contribute to future studies on the interaction of Colletotrichum scovillei-Capsicum spp., a research line that is still unexploited in the main areas of this anthracnose fungus.

Fourteen novel microsatellite loci are described and characterized in two species of electric eels, Electrophorus variiand E. voltaifrom floodplains and rivers of the Amazon rainforest. These loci are polymorphic, highly informative, and have the capacity to detect reliable levels of genetic diversity. Likewise, the high combined probability of paternity exclusion value and low combined probability of genetic identity value obtained demonstrate that the new set of loci displays suitability for paternity studies on electric eels. In addition, the cross-amplification of electric eel species implies that it may also be useful in the study of the closely related E. electricus, and to other Neotropical electric fishes (Gymnotiformes) species as tested herein. Resumo Catorze novos loci microsatélites são descritos e caracterizados em duas espécies de poraquês, Electrophorus varii e E. voltai de planícies alagadas e rios da floresta amazônica. Esses loci são polimórficos, altamente informativos e têm a capacidade de detectar níveis confiáveis de diversidade genética. Da mesma forma, o alto valor de exclusão de paternidade combinado com a baixa probabilidade de identidade genética demonstra que o novo conjunto de loci exibe adequação para estudos de paternidade em poraquês. Além disso, a amplificação cruzada de espécies de peixes elétricos implica que também pode ser útil no estudo da espécie intimamente relacionada E. electricus, e de outras espécies de peixes elétricos neotropicais (Gymnotiformes).

Made available in DSpace on 2020-12-10T17:38:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-07-21 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Capsicum annuum is one of the most important horticultural crops worldwide. Anthracnose disease (Colletotrichum spp.) is a major constraint for chili production, causing substantial losses. Capsidiol is a sesquiterpene phytoalexin present in pepper fruits that can enhance plant resistance. The genetic mechanisms involved in capisidiol biosynthesis are still poorly understood. In this study, a 3 ' RNA sequencing approach was used to develop the transcriptional profile dataset of C. annuum genes in unripe (UF) and ripe fruits (RF) in response to C. scovillei infection. Results showed 4,845 upregulated and 4,720 downregulated genes in UF, and 2,560 upregulated and 1,762 downregulated genes in RF under fungus inoculation. Four capsidiol-related genes were selected for RT-qPCR analysis, two 5-epi-aristolochene synthase (CA12g05030, CA02g09520) and two 5-epi-aristolochene-1,3-dihydroxylase genes (CA12g05070, CA01g05990). CA12g05030 and CA01g05990 genes showed an early response to fungus infection in RF (24 h post-inoculation-HPI), being 68-fold and 53-fold more expressed at 96 HPI, respectively. In UF, all genes showed a late response, especially CA12g05030, which was 700-fold more expressed at 96 HPI compared to control plants. We are proving here the first high-throughput expression dataset of pepper fruits in response to anthracnose disease in order to contribute for future pepper breeding programs. Univ Estadual Londrina, Programa Posgrad Agron, Lab Ecofisiol & Biotecnol Agr, Londrina, Parana, Brazil Boyce Thompson Inst Plant Res, Ithaca, NY USA Univ Estadual Paulista, Inst Biociencias, Rio Claro, Brazil Empresa Brasileira Pesquisa Agr, Brasilia, DF, Brazil Univ Estadual Londrina, Lab Citogenet & Diversidade Vegetal, Londrina, Parana, Brazil Univ Estadual Norte Fluminense, Genet & Melhoramento Plantas, Campos Goytacazes, Goytacazes, Brazil Univ Estadual Paulista, Inst Biociencias, Rio Claro, Brazil FAPESP: 2017/01455-2

Although stalk and ear rot is a major disease affecting corn plants, little is known regarding the genetic variability of Stenocarpella maydis, its main causal agent. In this study, we evaluated inter-simple sequence repeat (ISSR) primers for analysis of genetic variability of the pathogen. For DNA analysis, six isolates of S. maydis were amplified using 42 ISSR primers. Polymorphic information content (PIC), marker index (MI), and resolving power (RP) were calculated for all primers. Of the 42 primers, 50 % showed high-quality amplification products. The average polymorphism was 90.4 %, and the average similarity among the isolates was 33 %. The PIC, MI, and RP values ranged from 0.31 to 0.45, 4.84 to 18.46, and 0.40 to 10.00, respectively. The primers UBC 848, 873, 808, 811, 807, 827, 861, 868, 809, and 835 were found to be the most informative for genetic variability analysis. Considerable genetic variation was observed in S. maydis, with a core set of 10 primers.

Myrtaceae species play an important role in maintaining the biodiversity of the Atlantic Forest. However, most species of this biome have not been studied. In this work we examined whether microsat...

Triticale (X Triticosecale Wittmack) is an intergeneric hybrid derived from a cross between wheat and rye. As a newly created allopolyploid, the plant shows instabilities during the meiotic process, which may result in the loss of fertility. This genomic instability has hindered the success of triticale-breeding programs. Therefore, strategies should be developed to obtain stable triticale lines for use in breeding. In some species, backcrossing has been effective in increasing the meiotic stability of lineages. To assess whether backcrossing has the same effect in triticale, indices of meiotic abnormalities, meiotic index, and pollen viability were determined in genotypes from multiple generations of triticale (P1, P2, F1, F2, BC1a, and BC1b). All analyzed genotypes exhibited instability during meiosis, and their meiotic index values were all lower than normal. However, the backcrosses BC1a and BC1b showed the lowest mean meiotic abnormalities and the highest meiotic indices, demonstrating higher stability. All genotypes showed a high rate of pollen viability, with the backcrosses BC1a and BC1b again exhibiting the best values. Statistical analyses confirmed that backcrossing positively affects the meiotic stability of triticale. Our results show that backcrossing should be considered by breeders aiming to obtain triticale lines with improved genomic stability.

Capsicum baccatum is one of the main pepper species grown and consumed in South America. In Brazil, it is commonly cultivated by family farmers, using mostly the genotypes bishop's hat genotypes (locally cambuci) and red chili pepper (dedo-de-moça). This study had the objective of characterizing 116 C. baccatum accessions from different regions of Brazil, based on morphological fruit descriptors and AFLP (Amplified Fragment Length Polymorphisms) markers. Broad phenotypic variability among the C. baccatum accessions was detected when using morphological fruit descriptors. The Ward modified location model (Ward-MLM) discriminated five groups, based mainly on fruit shape. Six combinations of AFLP primers detected polymorphism in 97.93% of the 2466 identified bands, indicating the high genetic variability in the accessions. The UPGMA coincided with the Bayesian clustering analysis and three large groups were formed, separating the wild variety C. baccatum var. praetermissum from the other accessions. There was no relation between genetic distance and geographical origin of the accessions, probably due to the intense exchange of fruits and seeds between farmers. Morphological descriptors used together with AFLP markers proved efficient in detecting the levels of genetic variability among the accessions maintained in the germplasm collections. These results can be used as an additional source of helpful information to be exploited in C. baccatum breeding programs.