Genetic diversity of Euterpe edulis martius based on fruit traits / Diversidade genética de Euterpe edulis martius com base em características de frutos

Juçara (Euterpe edulis Martius) is a palm species from the Atlantic Forest whose fruits are important as a source of food to several individuals from the fauna of the region. Despite its ecological importance, juçara is found in the list of endangered species, due to the fragmentation of the forests and the illegal extraction of the heart of palm. We aimed to evaluate the inter- and intra-populational genetic diversity of E. edulis based on fruit and seed traits in forest fragments of the Espírito Santo State in Brazil. The aim was to generate information to be used in E. edulis breeding programs, or in the delineation of more efficient management and reforestation strategies. The study was carried out in 20 forest fragments and 198 fruit plants were sampled. Positive genetic association was observed between the evaluated traits, with the longitudinal diameter of the fruit (LDF) and the seed mass (SM) greatly affecting fruit mass (FM). The existence of inter- and intra-populational genetic divergence was proved. The genetic divergence found in E. edulis suggests that there is genetic material that can be explored in breeding programs and this information may also contribute to management strategies that can increase the species genetic diversity

Juçara (Euterpe edulis Martius) é uma espécie de palmeira da Mata Atlântica, que é importante como fonte de alimento para vários indivíduos da fauna. Apesar de sua importância ecológica, juçara é encontrada na lista de espécies ameaçadas à extinção, devido à fragmentação florestal e à extração ilegal do palmito. Nós tivemos como objetivo avaliar a diversidade genética inter e intra populacional de E. edulis com base em caracteres de frutos e sementes, em fragmentos florestais do Estado do Espírito Santo no Brasil, com o objetivo de gerar informações a serem utilizadas nos programas de melhoramento de E. edulis ou na delimitação de estratégias de manejo e reflorestamento mais eficientes. O estudo foi realizado em 20 fragmentos florestais e 198 plantas frutíferas foram amostradas. Foi observada uma grande associação genética positiva entre os caracteres avaliados, com as características diâmetro longitudinal dos frutos (LDF) e massa de sementes (SM) apresentando efeitos maiores do que a massa característica da fruta (FM). A existência de divergência genética inter e intrapopulacional foi comprovada. A divergência genética encontrada neste trabalho para E. edulis sugere a presença de material genético que vale a pena ser explorado em programas de melhoramento e essa informação também pode contribuir com estratégias de manejo para aumentar a diversidade genética das espécies.

Repeatability analysis of guava fruit and leaf characteristics / Análise de repetibilidade de características de frutos e folhas de goiaba

Psidium guajava L. (guava) is an important species that presents high genetic variability due to its mixed reproductive system, which is desired in breeding programs. Repeatability is an important tool for the selection of genotypes in pre-breeding studies. When genetic variability is present, the knowledge regarding the number of samples to be used in repeatability studies is indispensable. This study aims to determine the number of necessary measures while optimizing resources and maintaining the reliability of the results for the variables evaluated in P. guajava. The experiment was carried out with genotypes from three Brazilian States: Espírito Santo, São Paulo, and Minas Gerais, and a total of 79 P. guajava genotypes were collected. The following characteristics were evaluated: young leaf length and width; developed leaf length and width; fruit length; fruit diameter and fruit cavity diameter; and fruit weight and pulp weight. For the evaluated characteristics, deviance, permanent phenotypic and temporary environment variance, coefficients of repeatability and determination, accuracy and the number of estimated measurements required were determined. We established that the number of measurements required in repeatability analysis for a coefficient of repeatability with a reliability of 80% is four, for the measurements of developed leaf width, pulp weight, fruit diameter, and fruit cavity diameter

Psidium guajava L. (goiaba) é uma espécie importante que apresenta alta variabilidade genética devido ao seu sistema reprodutivo misto, o que é desejado em programas de melhoramento. A repetibilidade é uma ferramenta importante para a seleção de genótipos em estudos de pré-melhoramento.Quando a variabilidade genética está presente, o conhecimento sobre o número de amostras a serem usadas em estudos de repetibilidade é indispensável. Este estudo tem como objetivo determinar o número de medidas necessárias, otimizando recursos e mantendo a confiabilidade dos resultados para as variáveis avaliadas em P. guajava. O experimento foi conduzido com genótipos de três estados brasileiros: Espírito Santo, São Paulo e Minas Gerais, e um total de 79 genótipos de P. guajava foram coletados. As seguintes características foram avaliadas: comprimento e largura das folhas jovens; comprimento e largura das folhas desenvolvidas; comprimento do fruto; diâmetro do fruto e diâmetro da cavidade do fruto; e peso do fruto e peso da polpa. Para as características avaliadas, foram determinados os desvios, a variância fenotípica permanente e temporária do ambiente, os coeficientes de repetibilidade e determinação, a precisão e o número estimado de medidas necessárias. Foi estabelecido que o número de medições necessárias na análise de repetibilidade para um coeficiente de repetibilidade com uma confiabilidade de 80% é igual a quatro, para as medidas de largura de folha desenvolvida, peso da polpa, diâmetro do fruto e diâmetro da cavidade do fruto.

Chemotype diversity of Psidium guajava L.

The essential oil of Psidium guajava L. has been studied for pharmacological and industrial purposes, without considering the plant's genotype regarding the heterogeneity of its composition. The present study aimed to characterize the chemotype diversity of the essential oil extracted from the leaves of 22 genotypes of P. guajava grown in two different environments in the state of Espírito Santo, Brazil, and to identify the different chemical markers present in these plants. Essential oil from the leaves of the P. guajava genotypes was extracted by hydrodistillation, and its chemical composition was analyzed by gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Thirty-three compounds were identified, comprising 87.5-99.0% of the total composition, with a prevalence of sesquiterpenes in all samples. The major compounds identified consisted of (E)-trans-Caryophyllene, α-Humulene, trans-Nerolidol, ß-Bisabolene, ß-Bisabolol, and Hinesol, the first of which was identified as a possible chemical marker for the species. Multivariate factor analysis of the chemical composition of P. guajava oil identified three chemotypes: Commercial - PAL, SEC, PS, PET, C7, C11, and C17MI, characterized by high levels of ß-Selinene, α-Selinene, Hinesol, and 14-hydroxy-epi-(E)-caryophyllene, with ß-Selinene and α-Selinene as the chemical markers; C10 and C13, exhibiting high levels of Elemol, trans-Nerolidol, trans-ß-Eudesmol, and (2Z, 6Z)-Farnesol, which were indicated as chemical markers, and Cortibel - C1, C2, C3, C4, C5, C6, C8, C9, C12, C14, C15, C16, C17LI, which retained high levels of α-Cedrene, cis-α-Bergamotene, α-Humulene, Humulene epoxide, epi-α-Cadinol, ß-Bisabolol, and α-Bisabolol, with ß-Bisabolol and α-Bisabolol as the chemical markers. The use of guava genotypes with different chemotypes, that are agronomically favorable to fruit production and essential oil exploitation adds value to the crop and renders it more sustainable. Given guava crops produce large amounts of leaf biomass, resulting from successive prunings, the extraction of their essential oil, which retains commercially valuable compounds, can be feasible.

Semisynthetic Phenol Derivatives Obtained from Natural Phenols: Antimicrobial Activity and Molecular Properties.

Semisynthetic phenol derivatives were obtained from the natural phenols: thymol, carvacrol, eugenol, and guaiacol through catalytic oxychlorination, Williamson synthesis, and aromatic Claisen rearrangement. The compounds characterization was carried out by 1H NMR, 13C NMR, and mass spectrometry. The natural phenols and their semisynthetic derivatives were tested for their antimicrobial activity against the bacteria: Staphylococcus aureus, Escherichia coli, Listeria innocua, Pseudomonas aeruginosa, Salmonella enterica Typhimurium, Salmonella enterica ssp. enterica, and Bacillus cereus. Minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values were determined using concentrations from 220 to 3.44 µg mL-1. Most of the tested compounds presented MIC values ≤220 µg mL-1 for all the bacteria used in the assays. The molecular properties of the compounds were computed with the PM6 method. Through principle components analysis, the natural phenols and their semisynthetic derivatives with higher antimicrobial potential were grouped.