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The Atlantic Forest is one of the most threatened biomes in the world. Here, we use a common set of microsatellite markers to assess the genetic diversity and population structure of three species from the genus Psidium (P. guajava, P. macahense, and P. guineense), located in a disturbed environment of the Atlantic Forest, the restinga, in Espírito Santo, Brazil. Psidium guajava populations presented the highest number of alleles (95) followed by P. guineense (81) and P. macahense (68). The genetic variability was high (P. guajava = 0.71; P. guineense = 0.74; P. macahense = 0.63), with greater variation within populations (72 to 84%) than among populations (15 to 27%), reflecting elevated values of genetic differentiation (P. guajava, F

The objective of this work was to evaluate the vegetative development of radish seedlings in different organic substrates with seeds from two types of commercial packing. The completely randomized design was used in a 4 x 2 factorial scheme, consisting of four substrates (commercial, tanned bovine manure, mixed organic compound and vermicompost) and two seed packings (aluminized envelope and can), with eight replications, totalizing 64 seedlings. The biometric evaluations of the seedlings were carried out on the 14th day after sowing, and the following phytotechnical parameters were evaluated: leaf number, total fresh mass; fresh mass from aerial part and fresh mass from the root. According to the results, the commercial, vermicompost and mixed organic substrates provided the best results for the variables evaluated when the can was used.

The variation in the climatic conditions throughout the year can influence the foliar nutrient contents in Coffea canephora, impacting the fertilization management. We evaluated the influence of the climatic seasonality on the foliar nutrient contents of 28 C. canephora genotypes cultivated at 850 meters of altitude, in cold winter. The work was carried out in Morrinhos, State of Goias, Brazil. A randomized complete block design in a 2 x 28 factorial arrangement was used, with two crop seasons, winter and summer, and 28 C. canephora genotypes, with four replications, each replicate composed by five plants, and a spacing of 3.5 m x 1.0 m. The third and fourth pairs of leaves, of productive branches located in the middle third of the plant, were collected in six-year-old crops. The leaves were dried, and the mineral contents were analyzed, they were, then, subjected to multivariate analysis of principal components, dissimilarity and clustering. The results reveal the existence of different nutritional contents among leaves collected in the winter and summer. There is a tendency of higher macro and icronutrient contents in leaves collected in the winter than in the summer. The nutritional diagnosis should consider the group of genotypes and the crop season.

The use of allelopathic compounds is an alternative for weeds control, since they present low toxicity when compared with the synthetic herbicides, that may cause several damages, as the contamination of the environment. Our objective was to determine the chemical composition and allelopathic properties of the essential oils of Psidium cattleianum, P. myrtoides, P. friedrichsthalianum, and P. gaudichaudianum on the germination and root growth of Lactuca sativa and Sorghum bicolor, and to evaluate their action on the cell cycle of root meristematic cells of L. sativa. The main compound found in all the studied species was (E)-caryophyllene (P. cattleianum-23.4 %; P. myrtoides-19.3%; P. friedrichsthalianum-24.6% and P. gaudichaudianum-17.0%). The different essential oils were tested at different concentrations on L. sativa and S. bicolor, reducing germination, germination speed index, and root and shoot growth of lettuce and sorghum seedlings. The cytotoxicity and aneugenic potential of these oils were evidenced by the reduction of the mitotic index and increase of the frequency of chromosomal alterations in L. sativa. The essential oils of the species of Psidium studied have potential to be used in weeds control.

Climate change prospections indicate large fluctuations in terrestrial temperature, what may change the zoning of coffee cultivation. This is particularly true for Coffea canephora (conilon or robusta coffee) to which some suitable areas may become inappropriate. Thus, conilon cultivation at high altitudes may be an option to establish C. canephora, mitigating the possible effects of productive areas loss. In this context, the aim of this work was to evaluate the productivity, adaptability and stability of 28 C. canephora genotypes cultivated at 850 m above sea level, under climatic conditions where the minimum temperature is the limiting factor for the species. A random block design with four replicates x five plants per replicate was used. The genotype x environment interaction was investigated using stability and adaptability analyzes based on the mixed model of restricted maximum likelihood / best linear unbiased prediction (REML/BLUP). The genotypes presented heritability of high magnitude, indicating the precision of selection. Six genotypes (NV2, NV8, P1, 3V, Verdim TA and A1) were highlighted for productivity, adaptability and stability at high-altitude and low temperature.

In this study, we characterized DArTseq-derived SNPs for species of Psidium, an important Neotropical genus within the family Myrtaceae. Nine Psidium species were used for the identification and characterization of an interspecific set of SNPs. The samples chosen represented a wide range of variation regarding agronomic traits and geographical origin. The samples were genotyped using the DarTseq methodology. This approach, associated with annotation analysis, generated a set of conserved, polymorphic, and possibly functional SNPs. Most of the SNPs in coding regions of Psidium were annotated for the gene ontology classes. We observed high interspecific diversity among species and considerable intraspecific genetic diversity in native species (P. cattleyanum, P. myrtoides, P. acidum, and P. oblongatum). Psidium guajava, a cultivated species, shows low diversity and shares genetic similarities with the tetraploid P. guineense. The group of markers selected in this study will contribute to the development of a panel of interspecific SNPs for Psidium. Our investigation will support further studies regarding genetic variability, diversity, phylogeny, cytogenetics, and other relationships among Psidium species, constituting essential information for the creation, conservation, management, and use of genetic resources in breeding programs.

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.

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.

Leaf essential oils of guava (Psidium guajava L., Myrtaceae) show intraspecific variation in chemical composition. The essential oils of 21 P. guajava genotypes, obtained in each season in 2015 and 2016, were analyzed via GC-FID and GC–MS to detect composition variability due to seasonal fluctuation and a total of 35 compounds were identified. Qualitative and semi-quantitative variations were observed in different genotypes and within same genotypes during different seasons. Overall, the genotypes showed a predominance of sesquiterpenes with a relative area > 70%. Spring was the most varied season, revealing a decrease in hydrogenated sesquiterpenes and an increase of oxygenates. Precipitation data and daily temperatures during the experiment were registered at the time of guava leaf sampling to verify whether this phenomenon was due to a seasonal condition. We found that climatic variations were not the primary influence on this result. Phenological factors like as flowering showed a decrease in compounds like (E)-Caryophyllene and α-Humulene in the essential oils of all studied genotypes and were determined to be influenced by that cyclic phenomenon. Hence, due to the variations that occur in the chemical compounds the harvesting of leaves for the extraction of essential oils should be performed according to the highest concentrations of the active principles.

The palm tree juçara (Euterpe edulis Mart) is considered one of the most important and threatened native species in the Atlantic Forest. The search for juçara seeds (Euterpe edulis Martius) has increased, generating a need for technologies favorable to their production, quality and conservation. The aim of this study was to describe the seed germination patterns of 45 juçara accessions by using a nonlinear model to examine the behavior of these patterns and select superior genotypes. After clustering 45 juçara accessions into four groups, four nonlinear models, namely, the logistic, Gompertz, von Bertalanffy and Weibull models, were tested based on their fit for each group of accessions. The Gompertz model presented the best fit to describe the germination growth curve of E. edulis seeds. Groups 3 and 4 presented the highest daily germination rates and were considered the most vigorous. Analysis of deviance was performed, revealing genetic variability among the genotypes in terms of seed germination and vigor. It was possible to find a nonlinear model that best explained our data, and this model may also be a promising model for other palm tree species. It is possible to select genotypes based on the characters we analyzed, due to the elevated genetic variability.

Botanical insecticides based on oils and plant extracts have proven to be an efficient alternative method for pest control, as required by agroecological systems. Tephrosia vogelii (Hook.f.) has been used in agriculture as a source of green manure and in the control of pests and diseases. However, there are few studies regarding the use of compounds derived from the secondary metabolism of this plant. Chemical compounds present in the essential oil of Tephrosia vogelii flowers were identified, aiming at its use to control the aphid Cerosipha forbesi in the strawberry crop. Bioassays were carried out under laboratory and semi-field conditions, with different concentrations of the essential oil and the lethal concentrations LC50 and LC90 were estimated. Only two groups of terpenic compounds were identified in the essential oil of T. vogelii: monoterpenic hydrocarbons (alpha-pinene; limonene and ocimene) and oxygenated sesquiterpenes (nerolidol, spathulenol and farnesol). The essential oil of T. vogelii presented toxic effect against C. forbesi, with the LC50 and LC90 of the insect population estimated at 0.106 and 0.380 mL/L, respectively. Under semi-field conditions, mortality increased at higher concentrations, and the LC50 and LC90 were estimated at 0.114 mL/L and 0.465 mL/L, respectively. Mortality over 90% was observed after 24 h of the essential oil application, for all of the tested concentrations, showing an insecticidal action of the oil against the aphid C. forbesi.

Myrteae is the most diverse tribe, in number of species and genera, of the family Myrtaceae, representing half of the family’s biodiversity. Analysis of universal cross-transferable genetic markers across genera/species is essential and may significantly contribute towards the better understanding of species systematics and evolution. In the present study, a total of 133 sequence-tagged microsatellite markers from Psidium guajava L. were evaluated for transferability to forty-four species of the tribe Myrteae, which represent nine different genera of the family Myrtaceae (Myrciaria, Plinia, Pimenta, Acca, Campomanesia, Psidium, Eugenia, Syzygium, and Eucalyptus). Cross-transferable simple sequence repeat (SSR) markers were employed to evaluate the phylogenetic relationships between them. The results indicated a high level of congruence with earlier reports regarding genetic divergence and taxa clustering. An analysis to optimize the number of SSR markers was also performed, revealing that even a small amount is capable of determining the systematic positions of different genera/species of the Myrteae tribe.

El exito en el proceso de la germinacion depende del agua que ingresa a traves de los tejidos que rodean la semilla. La presencia de sal reduce el gradiente entre el suelo y la superficie de la semilla, lo que limita la absorcion del agua por la semilla. El objetivo de la investigacion fue evaluar el efecto de la salinidad y la temperatura sobre la germinacion de semillas de zanahoria. El potencial osmotico utilizado en las soluciones fue 0,0 (control); - 0,4; -0,8; -1,2, -1,6 y 2,0 Mpa, obtenidas con el uso de NaCl, y las temperaturas utilizadas fueron 15 °C 20 °C 25 °C 35 °C 15-35 °C y 25- 35 °C. En las evaluaciones, se utilizo un lote comercial de Brasilia. En las evaluaciones de semillas de zanahoria cv se midieron porcentaje de germinacion, indice de velocidad de germinacion, peso fresco y seco de las plantulas. Las medias fueron sometidos a analisis de regresion. En el ensayo, la germinacion se redujo en 35 °C en potencial osmotico mayor que -0,8 MPa. Las temperaturas de 20 °C y 25 °C son mas favorables para la germinacion y la tasa de germinacion de las condiciones ensayadas.

Podem ocorrer diferencas nas caracteristicas fisiologicas, bioquimicas, anatomicas e de crescimento de uma planta quando esta for submetida a modificacoes nos niveis de luminosidade ao qual esta adaptada. A resposta da planta as diferentes condicoes de intensidade luminosa e importante para determinar o seu potencial de crescimento e ocorrencia e, tambem, avaliar a sua capacidade competitiva em diferentes condicoes ambientais. O objetivo deste trabalho foi avaliar as caracteristicas de plantas de rabanete submetidas a diferentes niveis de luminosidade. O experimento foi conduzido em casa de vegetacao e o delineamento experimental utilizado foi de blocos ao acaso com sete repeticoes. Os tratamentos foram compostos por quatro intensidades de radiacao solar (100%, 70%, 50% e 30% de luminosidade). A reducao de intensidade de luz para 70%, 50% e 30% foi obtida com o uso de tela sombrites de 30%, 50% e 70%, respectivamente. Foram avaliados os teores de clorofila A, B e total, numero de folhas, area foliar, massa da materia fresca e seca da parte aerea e sistema radicular. Conclui-se que os niveis de sombreamento de 30%, 50% e 70% prolongaram o ciclo de desenvolvimento da cultura e promoveram a reducao no tamanho e na massa das raizes tuberosas.

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 derivative...

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 Espirito 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, β-Bisabolene, β-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 β-Selinene, α-Selinene, Hinesol, and 14-hydroxy-epi-(E)-caryophyllene, with β-Selinene and α-Selinene as the chemical markers; C10 and C13, exhibiting high levels of Elemol, trans-Nerolidol, trans-β-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, β-Bisabolol, and α-Bisabolol, with β-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.

A jabuticaba pode ser consumida in natura ou processada e a sua casca, subproduto do processamento, pode ser reaproveitada devido aos seus constituintes. O objetivo deste trabalho foi estudar a caracterização e utilização da casca da jabuticaba visando o aproveitamento dos seus constituintes para obtenção de outros produtos. O estudo consistiu numa pesquisa realizada através de trabalhos encontrados na base de dados Scielo, além de resumos, livros, teses e dissertações. Constatou-se que a casca da jabuticaba é fonte de vitaminas e minerais, carboidratos, fibras, substâncias antioxidantes e ácidos orgânicos; e pode ser utilizada na fabricação de vários produtos e apresenta vários benefícios para a saúde humana. Conclui-se que a casca da jabuticaba apresenta vários compostos de interesse da indústria farmacêutica e alimentícia e pode ser utilizada no preparo de diferentes produtos alimentícios, em substituição, para o enriquecimento ou como corante natural.