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961.

The species Piper hispidinervum, Piper aduncum, and Piper affinis hispidinervum have essential oils with high levels of safrole, dillapiole, and sarisan, respectively. Safrole is important for pharmaceutical and chemical industries, while dillapiole and sarisan are promising compounds to control insects and fungi. These species are very similar morphologically and their taxonomy is controversial. Divergent hypotheses consider P. aduncum and P. hispidinervum either as a single species or as distinct taxa, while P. affinis hispidinervum is inferred to be a natural hybrid or a chemotype of P. hispidinervum. Delimiting the taxonomic boundaries would be helpful for germplasm conservation and breeding programs. This study aimed to undertake a detailed analysis of P. aduncum, P. hispidinervum, and P. affinis hispidinervum karyotype and rDNA sites. Genomic in situ hybridization (GISH) was used to establish genomic homology among species and to test the natural hybridization hypothesis for origin of P. affinis hispidinervum. Karyotype traits were similar for all three species: 2n = 26 small chromosomes, predominantly metacentric. All three species exhibited CMA+ bands on the secondary constriction of chromosome pair 4. A size-heteromorphic 35S rDNA site was co-localized with the CMA+ band. A 5S rDNA site was located in the proximal region of chromosome pair 7. The patterns of genomic hybridization revealed that the repetitive DNA fraction of the species is highly similar in terms of proportion of genome, sequence type, and distribution. Our findings did not allow us to differentiate the three species and point to the importance of deeper genomic studies to elucidate the taxonomic controversy.

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962.

A new parasitic copepod, Tiddergasilus bipartitus n. sp. (Copepoda, Ergasilidae), is described herein based on three adult females found attached to the gills of the yellow-tail lambari Astyanax lacustris (Lütken), sampled in Pardo River, municipality of Botucatu, São Paulo State, Brazil. Tiddergasilus bipartitus n. sp. was recognized as a new member of the monotypic genus Tiddergasilus Marques & Boeger, 2018 by having: antennule 6-segmented; maxillary basis armed with 2 terminal teeth and ornamented with multiple spinules; second and third leg both with endopod 3-segmented. The new copepod can be distinguished from its congener, Tiddergasilus iheringi (Tidd, 1942), by the morphology of the antennal claw, number of somites/segments in abdomen and fourth leg, and by the ornamentation of the first leg. This report expands the geographic distribution and diversity of fish species parasitized with Tiddergasilus spp. in Brazil. Moreover, it also represents the first report of an ergasilid species in the Pardo River. A list of diagnostic features for the Brazilian species of Ergasilus von Nordmann, 1832 is provided herein, in order to aid comparisons with the species of this complex genus.

  相似文献   
963.
International Journal of Primatology - It is important to understand how sympatric congeners can co-occur within the same landscapes to better understand niche differentiation and how each species...  相似文献   
964.

The present study describes a new regeneration system based on somatic embryogenesis from mature endosperm Passiflora cincinnata Mast. cultures. Moreover, the morpho-agronomic and phenological traits, as well as enzymatic activity of regenerated triploid emblings are compared to those of diploids. Mature endosperms were cultured on Murashige and Skoog medium supplemented with various concentrations (4.5–45.2 µM) of 2,4-dichlorophenoxyacetic acid (2,4-D) and 4.5 μM 6-benzylaminopurine (BA). No plant growth regulators were included in the control group. Embryogenic calli were observed only in treatments supplemented with 13.6 and 18.1 µM 2,4-D?+?4.5 µM BA, with the highest number of somatic embryos per explant and regenerated plants (emblings) obtained with 18.1 µM 2,4-D. Most emblings (70%) were triploid (2n?=?3x?=?27), with a DNA amount (4.38 pg) similar to that of endosperm and 1.5 times greater than in diploid P. cincinnata seedlings (2n?=?2x?=?18), that contained 2.98 pg of DNA. While the number of organs and/or structures was akin to that in diploids, triploid emblings generally exhibited larger and longer vegetative and floral structures. The flower lifespan was also slightly altered by triploidy, nectar concentration was 27% higher, and the activity of plant defense enzymes β-1,3-glucanase and polyphenol oxidase was 29.8% and 22.1% higher. This study describes a new regeneration system for the production of phenotypic variants of this ornamental passion fruit species, opening new perspectives for future studies on genetic passion fruit breeding.

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965.
Journal of Plant Growth Regulation - The flowers of pagoda tree (Sophora japonica L.) are white, which limited its ornamental value and caused few researches on its flower color and anthocyanin...  相似文献   
966.
967.
acta ethologica - The Brazilian ruby, Heliodoxa rubricauda, is a forest species of hummingbird endemic to the Atlantic Forest. It belongs to an Andean clade of birds with robust and strong legs and...  相似文献   
968.
Journal of Plant Research - The syconium is the urn-shaped inflorescence shared by all species of the genus Ficus. The orifice at the apex of the syconium is called the ostiole, and it is covered...  相似文献   
969.
This study aimed to evaluate the performance of hydrogen peroxide vapour (HPV) to inactivate the chimpanzee adenovirus AZD1222 vaccine strain used in the production of recombinant COVID-19 vaccine for application in cleaning validation in pharmaceutical industries production areas. Two matrixes were tested: formulated recombinant COVID-19 vaccine (FCV) and active pharmaceutical ingredient (API). The samples were dried on stainless steel and exposed to HPV in an isolator. One biological indicator with population >106 Geobacillus stearothermophilus spores was used to validate the HPV decontamination cycle as standard. HPV exposure resulted in complete virus inactivation in FVC (≥5·03 log10) and API (≥6·40 log10), showing HPV efficacy for reducing chimpanzee adenovirus AZD1222 vaccine strain. However, the optimum concentration and contact time will vary depending on the type of application. Future decontamination studies scaling up the process to the recombinant COVID-19 vaccine manufacturing areas are necessary to evaluate if the HPV will have the same or better virucidal effectivity in each specific production area. In conclusion, HPV showed efficacy for reducing AZD1222 chimpanzee adenovirus strain and can be a good choice for pharmaceutical industries facilities disinfection during recombinant COVID-19 vaccine production.  相似文献   
970.
Environmental Biology of Fishes - The ichthyofauna of a large lake located in one of the biggest urban centers in Southern South America was studied for 15 years. Variations in...  相似文献   
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