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MAIN CONCLUSION: The hop phenological cycle was described in subtropical condition of Brazil showing that flowering can happen at any time of year and this was related to developmental molecular pathways. Hops are traditionally produced in temperate regions, as it was believed that vernalization was necessary for flowering. Nevertheless, recent studies have revealed the potential for hops to flower in tropical and subtropical climates. In this work, we observed that hops in the subtropical climate of Minas Gerais, Brazil grow and flower multiple times throughout the year, independently of the season, contrasting with what happens in temperate regions. This could be due to the photoperiod consistently being inductive, with daylight hours below the described threshold (16.5 h critical). We observed that when the plants reached 7-9 nodes, the leaves began to transition from heart-shaped to trilobed-shaped, which could be indicative of the juvenile to adult transition. This could be related to the fact that the 5th node (in plants with 10 nodes) had the highest expression of miR156, while two miR172s increased in the 20th node (in plants with 25 nodes). Hop flowers appeared later, in the 25th or 28th nodes, and the expression of HlFT3 and HlFT5 was upregulated in plants between 15 and 20 nodes, while the expression of HlTFL3 was upregulated in plants with 20 nodes. These results indicate the role of axillary meristem age in regulating this process and suggest that the florigenic signal should be maintained until the hop plants bloom. In addition, it is possible that the expression of TFL is not sufficient to inhibit flowering in these conditions and promote branching. These findings suggest that the reproductive transition in hop under inductive photoperiodic conditions could occur in plants between 15 and 20 nodes. Our study sheds light on the intricate molecular mechanisms underlying hop floral development, paving the way for potential advancements in hop production on a global scale.

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Booralana nickorum sp. nov. is described from the deep-water slope of the Exuma Sound, The Bahamas, from depths of 540 to 560 metres. It is the fourth species to be assigned to the genus and the second species described from the Western North Atlantic. The species can be distinguished from Booralana tricarinata Camp and Heard, 1988 and the other species by the sub-triangular pleotelson and the uropodal exopod of mature males being far longer than endopod, with both rami extending well beyond the posterior margin of the pleotelson. Additionally, pleopods 3 and 4 lack a prominent angle at midpoint of ramus.

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MADS-box transcription factors (TFs) are involved in multiple plant development processes and are most known during the reproductive transition and floral organ development. Very few genes have been characterized in the genome of Humulus lupulus L. (Cannabaceae), an important crop for the pharmaceutical and beverage industries. The MADS-box family has not been studied in this species yet. We identified 65 MADS-box genes in the hop genome, of which 29 encode type-II TFs (27 of subgroup MIKCC and 2 MIKC*) and 36 type-I proteins (26 α, 9 ß, and 1 γ). Type-II MADS-box genes evolved more complex architectures than type-I genes. Interestingly, we did not find FLOWERING LOCUS C (FLC) homologs, a transcription factor that acts as a floral repressor and is negatively regulated by cold. This result provides a molecular explanation for a previous work showing that vernalization is not a requirement for hop flowering, which has implications for its cultivation in the tropics. Analysis of gene ontology and expression profiling revealed genes potentially involved in the development of male and female floral structures based on the differential expression of ABC homeotic genes in each whorl of the flower. We identified a gene exclusively expressed in lupulin glands, suggesting a role in specialized metabolism in these structures. In toto, this work contributes to understanding the evolutionary history of MADS-box genes in hop, and provides perspectives on functional genetic studies, biotechnology, and crop breeding.

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Coffee (Coffea arabica L.) presents an asynchronous flowering regulated by an endogenous and environmental stimulus, and anthesis occurs once plants are rehydrated after a period of water deficit. We evaluated the evolution of Abscisic Acid (ABA), ethylene, 1-aminocyclopropane-1-carboxylate (ACC) content, ACC oxidase (ACO) activity, and expression analysis of the Lysine Histidine Transporter 1 (LHT1) transporter, in the roots, leaves, and flower buds from three coffee genotypes (C. arabica L. cv Oeiras, Acauã, and Semperflorens) cultivated under field conditions with two experiments. In a third field experiment, the effect of the exogenous supply of ACC in coffee anthesis was evaluated. We found an increased ACC level, low ACO activity, decreased level of ethylene, and a decreased level of ABA in all tissues from the three coffee genotypes in the re-watering period just before anthesis, and a high expression of the LHT1 in flower buds and leaves. The ethylene content and ACO activity decreased from rainy to dry period whereas the ABA content increased. A higher number of opened and G6 stage flower buds were observed in the treatment with exogenous ACC. The results showed that the interaction of ABA-ACO-ethylene and intercellular ACC transport among the leaves, buds, and roots in coffee favors an increased level of ACC that is most likely, involved as a modulator in coffee anthesis. This study provides evidence that ACC can play an important role independently of ethylene in the anthesis process in a perennial crop.

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Objetivos. Detectar metabolitos secundarios y caracterizar estructuras químicas de flavonoides de los extractos metanólicos de hojas de dos tipos de Ruta chalepensis L. «ruda macho¼ y «ruda hembra¼. Materiales y métodos. Se elaboraron extractos metanólicos de hojas de Ruta chalepensis L. «ruda macho¼ y «ruda hembra¼. Se llevó a cabo la prueba de solubilidad de los extractos obtenidos utilizando solventes de polaridad creciente. Posteriormente, se detectaron los metabolitos secundarios presentes en los extractos mediante la ejecución del tamizaje fitoquímico, donde se utilizaron diversos reactivos Shinoda, Dragendorff, Borntrager, entre otros. Se utilizó el método de cromatografía en capa fina, espectrofotometría UV/Vis y reactivos de desplazamiento para caracterizar las estructuras químicas de los flavonoides presentes en los extractos metanólicos de hojas de Ruta chalepensis L. «ruda macho¼ y «ruda hembra¼. Resultados. El extracto metanólico de hojas de Ruta chalepensis L. «ruda macho¼ presentó una mayor afinidad por solventes polares, mientras que en el extracto metanólico de hojas de Ruta chalepensis L. «ruda hembra¼ fue soluble en solventes medianamente polares. Se detectaron metabolitos secundarios tales como: taninos, alcaloides y flavonoides en ambos tipos. Por otro lado, se caracterizaron diez estructuras químicas tipo flavonoides a través del análisis de los espectros UV/Vis y utilizando reactivos de desplazamiento, de las cuales cinco corresponden a Ruta chalepensis L. «ruda macho¼ y las restantes a Ruta chalepensis L. «ruda hembra¼. Conclusiones. Se detectaron algunos metabolitos secundarios caracterizándose diez estructuras químicas de flavonoides en los extractos metanólicos de hojas de Ruta chalepensis L. «ruda macho¼ y «ruda hembra¼. Asimismo, la presencia de rutina en «ruda hembra¼ es la principal característica que la diferencia de «ruda macho¼.

Objective. To detect the secondary metabolites and characterize the chemical structures of the flavonoids in the methanolic extracts of leaves of the Ruta chalepensis L. "ruda macho" and "ruda hembra" types. Materials and methods. We elaborate the methanolic extracts of Ruta chalepensis L. leaves "ruda macho" and "ruda hembra". Then, the solubility test of the obtained extracts was carried out using solvents of increasing polarity. Subsequently, the secondary metabolites present in the extracts were detected by executing the phytochemical screening, various reagents were used: Shinoda, Dragendorff, Borntrager, among others. The method of thin layer chromatography, UV / Vis spectrophotometry and displacement reagents was used to characterize the chemical structures of the flavonoids in the methanolic extracts of leaves of the Ruta chalepensis L. "ruda macho" and "ruda hembra". Results. The methanolic extract of Ruta chalepensis L. "ruda macho" leaves showed a greater affinity for polar solvents, while the methanolic extract of Ruta chalepensis L. "ruda hembra" leaves was soluble in moderately polar solvents. Secondary metabolites were detected, such as: tannins, alkaloids and flavonoids in both types. On the other hand, ten flavonoidtype chemical structures were characterized through the analysis of UV / Vis spectra and using displacement reagent, of which five of them correspond to Ruta chalepensis L. "ruda macho" and the others to Ruta chalepensis L. "ruda hembra". Conclusions. Some secondary metabolites were detected and ten chemical structures of flavonoids were characterized in the methanolic extracts of Ruta chalepensis L. "ruda macho" and "ruda hembra" leaves. Likewise, the presence of rutina in "ruda hembra" is the main characteristic that differentiates it from "ruda macho".

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Objetivo. Determinar la estructura química de flavonas aisladas del extracto metanólico de hojas de Marrubium vulgare L. "Cordón", mediante comparación con lo publicado por TJ Mabry. Materiales y métodos. Se elaboró extracto metanólico de hojas de Marrubium vulgare L. "Cordón" . Se determinó su solubilidad en solventes de polaridad creciente. Se detectaron los componentes químicos utilizando tricloruro férrico, reactivo de Shinoda, gelatina, entre otros reactivos cromogénicos. Se realizó cromatografía en capa fina y por espectroscopía UV/VIS se propusieron estructuras químicas para los metabolitos tipo flavonas presentes en el extracto metanólico de hojas de Marrubium vulgare L. "Cordón" . Resultados. El extracto metanólico de hojas de Marrubium vulgare L. "Cordón" fue soluble en solventes de mediana polaridad. Los metabolitos secundarios encontrados fueron flavonoides, taninos y alcaloides. Se propusieron estructuras químicas de flavonas a través del análisis de los espectros UV/Vis, y por comparación con tablas publicadas en la literatura. Conclusiones. Se determinaron nueve estructuras químicas de metabolitos secundarios tipo flavonas del extracto metanólico de hojas de Marrubium vulgare L. "Cordón" mediante comparación con lo publicado por TJ Mabry.

Objective. Determine the chemical structure of flavones isolated from the methanolic extract of Marrubium vulgare L. "Cordón" leaves by comparison with that published by TJ Mabry. Materials and methods. Methanolic leaf extract of Marrubium vulgare L. "Cordón" was prepared. Its solubility in solvents of increasing polarity was determined. The chemical components were detected using ferric trichloride, Shinoda reagent, gelatin, among other chromogenic reagents. Thin layer chromatography was performed and by UV / VIS spectroscopy chemical structures were proposed for flavone metabolites present in the methanolic leaf extract of Marrubium vulgare L. "Cordón". Results. The methanolic extract of Marrubium vulgare L. "Cordón" leaves was soluble in medium polarity solvents. The secondary metabolites found were flavonoids, tannins and alkaloids. Chemical structures of flavones were proposed through the analysis of the UV / Vis spectra, and by comparison with tables published in the literature. Conclusion. Nine chemical structures of flavone secondary metabolites of the methanolic leaf extract of Marrubium vulgare L. "Cordón" were determined by comparison with that published by TJ Mabry.

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