Loss of biodiversity and ecosystem degradation become major concerns worldwide, making the conservation process an important strategy for maintaining biodiversity. Capsicum chinense Jacq. is the most Brazilian species of the genus, with representatives in different biomes. Anthropic pressure, such as burns, real estate speculation, and changing cultivation habit has led to risks of genetic erosion. Conservation and characterization of conserved accessions are paramount to ensure genetic diversity, useful for the bioeconomy and for genetic improvement. We report the characterization of 55 C. chinense accessions from four different regions of Brazil and one accession from Peru. The accessions were characterized based on 37 morpho-agronomic variables, Inter Simple Sequence Repeats—ISSR and Simple Sequence Repeat—SSR. Qualitative descriptors were analyzed using a descriptive statistical, while the quantitative descriptors were analyzed via F test and significant differences in mean values were separated using Scott-Knott test. The relative contribution of each quantitative trait was determined. A correlation between morphological and molecular distances was calculated. Color of ripe fruit and fruit shape had the largest number of observed classes. Six distinct groups and the joint analysis presented an entanglement rate of 0.58, evidencing the divergence of accessions between the groups of both dendrograms. Bayesian analysis allowed the distinction of two clusters for SSR. A significant variability was observed among accession with potential to integrate several breeding programs.

The plant hormones brassinosteroids (BR) and ethylene (ET) act together to regulate plant metabolism. We used BR and 1-methylcyclopropene (1-MCP, an ET action inhibitor) to elucidate the interactions between both hormones for the regulation of mitochondrial respiratory pathways in papaya fruit. The exogenous application of the 24-epibrassinolide (epiBR) enhanced the alternative oxidase (AOX) capacity. While treatment with Brz2001 (Brz is a specific inhibitor of the BR synthesis) also enhanced AOX capacity, these effects lacked in fruit treated simultaneously with epiBR and Brz. Changing the BR level had no effect on ET emission rate in the first 24 h, but a reduction in ET emission was observed in Brz-treated fruit on the fifth day. Together with Brz, epiBR increased the ET production on the fifth day, following the day in which the treatment was carried out. When the ET sensitivity of fruit was inhibited by the application of 1-MCP, the effects of epiBR and Brz were opposite to those obtained without 1-MCP. AOX capacity was slightly inhibited by epiBR in fruit pre-treated with 1-MCP. Data suggest that BR and ET act antagonistically, therefore regulating, directly or indirectly, AOX capacity during papaya fruit ripening.

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The collection and characterization of tomato germplasm are of relevant importance for agriculture. This study aimed to collect and characterize, by way of morphological description and statistical tools for the composition of groups, tomato accesses from the Southern and Serrana regions of the State of Espírito Santo, as well as to establish the tomato germplasm bank of the Ifes - Campus de Alegre. Thirty-seven accessions were collected from different commercial locations of Espírito Santo. The experiment was conducted in the Ifes Campus de Alegre in the Agroecology sector. For the morpho-agronomic characterization, sixteen essential descriptors were used, nine quantitative and seven qualitative. In the color of the ripe fruit, there was the formation of five distinct groups with the colors yellow, green, orange, pink and red. In the format of the fruit, three groups were formed, slightly flattened, flattened and rounded. The ANOVA showed that there was a significant difference for all the quantitative characteristics evaluated. According to the Ward-MLM procedure, due to the high likelihood function in group seven (from 130.71), it was possible to group the 37 genotypes into seven groups. The greatest dissimilarity was observed in groups V and VII with a distance of 330.02, and the least dissimilar ones, groups IV and VI, with 8.21. Genetic variability was detected in tomato germplasm for the morpho-agronomic characteristics. Many of the accessions are promising sources of phenotypes of interest to the Ifes germplasm bank.

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resUmo -este trabalho teve como objetivo comparar a atividade respiratória em mitocôndrias isoladas e os atributos físicos e químicos da polpa de dois híbridos de mamão, uenF/caliman01 (uc01) e tainung01, durante o amadurecimento dos frutos. O amadurecimento dos frutos não mostrou diferenças significativas entre os genótipos na luminosidade (L), no croma (c) e no ângulo hue da casca. a perda de massa (Pm) e as firmezas do fruto (FF) e do mesocarpo (FM) diferiram entre os genótipos, sendo que a FF e a FM diminuíram com o tempo após a colheita, ao contrário da Pm, que aumentou no mesmo período. a atividade respiratória nas mitocôndrias isoladas mostrou diferenças entre os genótipos quanto à respiração total (Rt), sendo maior e decrescente no tainung01 e constante no uc01 durante o amadurecimento dos frutos. durante esse período, verificou-se que a participação da via oxidase alternativa (AOX) foi crescente, contra uma participação decrescente da via citocromo oxidase (COX) em ambos os híbridos, indicando um crescente desacoplamento das mitocôndrias, o que pode estar associado às rápidas transformações bioquímicas que acarretam a senescência do órgão. a partir desses resultados, sugere-se investigar materiais genéticos com menor atividade AOX, ou formas de minimizar a atividade respiratória nos frutos em pós-colheita. A AOX apresentou alta correlação positiva com a Pm e negativa com a FF e a Fm. o inverso foi observado para COX. A RT apresentou correlação positiva apenas com a FM. As correlações apontam a viabilidade de estimar a atividade respiratória por meio de análises mais simples, como a Pm, a FF e a Fm, facilitando a pesquisa na área. termo de indexação: amadurecimento, Carica papaya L., citocromo c oxidase, oxidase alternativa, respiração.respirAtorY ActivitY in isolAted mitochondriA From the pUlp oF UenF/cAlimAn01 And tAinUng01 pApAYA in posthArvest FrUit conservAtion ABstrAct -this study had the object of comparing the respiratory activity in isolated mitochondria and the physical and chemical attributes of the pulp of two papaya hybrids, uenF/caliman01 and tainung01, during fruit ripening. The fruit ripening did not show significant differences between the genotypes with regard to lightness (L), chroma (C), and hue angle of the skin. The loss of mass (LM) and the firmness of fruit (FF) and mesocarp (Fm) differed between the genotypes, with FF and Fm decreasing with time after harvest, while Lm rose over the same period. the respiratory activity in the isolated mitochondria revealed differences between the genotypes with respect to total respiration (tR), being higher and with negative time-correlation function in tainung01 and constant in uc01 during fruit ripening. during this period the participation of alternative oxidase (AOX) pathway was crescent, against the decreasing participation of cytochrome c oxidase (COX) pathway in both hybrids was verified, indicating an increasing uncoupling of the mitochondria, which may be associated with the rapid biochemical transformations that cause the senescence o...

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