Anatomical aspects of the embryo and initial development of Oenocarpus minor Mart: a palm tree from the Amazon

The anatomy of the embryo and the initial germination phase of O. minor seeds are examined here. Ripe fruits were collected from five individuals, the pulp removed, and the seeds sown in beds with sandy substrate in a greenhouse with 50% shade. Germination follow-up was made by collecting different stages of development. The anatomical study done according to usual techniques of light microscopy. The embryo is capitate and occupies a central position in the basal region of the seed. The embryogenic axis is located in the proximal region in a position that is oblique to the cotyledon axis. The cotyledon is formed by parenchymatous, procambial and protodermic tissue. The vascular bundles lie along the peripheral zone of the distal region to the embryogenicaxis. After 14 days, the primary rootemerges; after 21 days, the first cotyledon sheath and after 35 days, the second cotyledon sheath, and the seedling emerges above the substrate. Germination is of the ligule adjacent type.Neste trabalho foi feita a anatomia do embrião e a fase inicial da germinação da semente de O. minor. Frutos maduros de cinco indivíduos foram despolpados e as sementes obtidas foram semeadas em canteiros contendo substrato areia em casa de vegetação com sombreamento a 50%. O acompanhamento da germinação foi feito através de coletas das diferentes fases do desenvolvimento. O estudo anatômico foi realizado conforme técnicas usuais de microscopia de luz. O embrião é capitado. O eixo embrionário localiza-se na região proximal em posição oblíqua ao eixo cotiledonar. O cotilédone é formado por tecido parenquimático, procambial e protodérmico. Os feixes vasculares ocorrem ao longo da zona periférica da região distal até ao eixo embrionário. Aos 14 dias é emitida a raiz primária. Aos 21 dias forma-se a primeira bainha cotiledonar e aos 35 dias a segunda bainha cotiledonar ocorrendo à emergência da plântula acima do substrato. A germinação é do tipo adjacente ligular

Randomized controlled trial of molnupiravir SARS-CoV-2 viral and antibody response in at-risk adult outpatients

Viral clearance, antibody response and the mutagenic effect of molnupiravir has not 77 been elucidated in at-risk populations. Non-hospitalised participants within 5 days of 78 SARS-CoV-2 symptoms randomised to receive molnupiravir (n=253) or Usual Care 79 (n=324) were recruited to study viral and antibody dynamics and the effect of molnupiravir on viral whole genome sequence from 1437 viral genomes. Molnupiravir accelerates viral load decline, but virus is detectable by Day 5 in most cases. At Day 14 (9 days post-treatment), molnupiravir is associated with significantly higher viral persistence and significantly lower anti-SARS-CoV-2 spike antibody titres compared to Usual Care. Serial sequencing reveals increased mutagenesis with molnupiravir treatment. Persistence of detectable viral RNA at Day 14 in the molnupiravir group is associated with higher transition mutations following treatment cessation. Viral viability at Day 14 is similar in both groups with post-molnupiravir treated samples cultured up to 9 days post cessation of treatment. The current 5-day molnupiravir course is too short. Longer courses should be tested to reduce the risk of potentially transmissible molnupiravir-mutated variants being generated

Efeitos de diferentes substratos e temperaturas na germinação de sementes de Foeniculum vulgare

RESUMO O funcho (Foeniculum vulgare) é uma espécie medicinal nativa da Europa e amplamente cultivada em todo o Brasil. Possui propriedades carminativas, digestivas e diuréticas. Dada a grande importância dessa espécie no âmbito medicinal, objetivou-se com este trabalho avaliar o efeito de diferentes substratos e temperaturas na germinação de sementes de funcho. Os tratamentos foram compostos de duas temperaturas sendo uma constante de 20ºC e outra alternada de 25-30 °C e três diferentes substratos: papel mata borrão (Germitest), areia e vermiculita, em esquema fatorial 3 x 2, com 4 repetições de 25 sementes. Foi avaliado o índice de velocidade de germinação (IVG), porcentagem de germinação (PG), comprimento da radícula (CR), massa fresca (MF) e seca (MS) de plântulas. A temperatura de 20 ºC proporcionou maiores IVG, porcentagens de germinação, comprimento de radícula e massa seca. A germinação de sementes de funcho não foi influenciada pelos diferentes substratos testados. Pelos resultados, conclui-se que a condição que permitiu maior porcentagem de germinação das sementes de funcho foi a temperatura de 20 °C atingindo 91% de germinação

Influence of plant age, chilling hours and genotype on the number of new shoots in red raspberry root systems

Little is known about the factors affecting vegetative propagation of raspberry plants by root buds to maximize plant production in the nurseries. The number of buds in the roots that can produce suckers is cultural (planting date, cane density, soil type, moisture, etc.) and climatic (temperature and photoperiod) dependent. Plant age is a factor that influences root system weight as a longer time for root development and chilling is an important factor in breaking raspberry bud dormancy. Two trials were set up. In the first trial the interaction between root age (corresponding to three planting dates – March 16, April 6 and April 27) and the time in the cold room (without chilling, 15 days, 30 days and 45 days at 5°C) was evaluated. In a second trial, the importance of genotype for root bud formation was analysed. Four genotypes from three origins (seeds from three female parents open pollinated) were used. In the first trial there was no interaction between chilling and plant age, but chilling had a significant impact on the number of suckers obtained, with the 30-day treatment being the most effective. In the second trial the genotypes were observed to be independent of origin, that is, in the same origin there were genotypes with differences of about 30 shoots.info:eu-repo/semantics/publishedVersio

Expression of the sucrose binding protein from soybean: renaturation and stability of the recombinant protein

The sucrose binding protein (SBP) belongs to the cupin family of proteins and is structurally related to vicilin-like storage proteins. In this investigation, a SBP isoform (GmSBP2/S64) was expressed in E. coli and large amounts of the protein accumulated in the insoluble fraction as inclusion bodies. The renatured protein was studied by circular dichroism (CD), intrinsic fluorescence, and binding of the hydrophobic probes ANS and Bis-ANS. The estimated content of secondary structure of the renatured protein was consistent with that obtained by theoretical modeling with a large predominance of b-strand structure (42%) over the a-helix (9.9%). The fluorescence emis- sion maximum of 303 nm for SBP2 indicated that the fluorescent tryptophan was completely buried within a highly hydrophobic environment. We also measured the equilibrium dissociation constant (K d ) of sucrose binding by fluorescence titration using the refolded protein. The low sucrose binding affinity (K d = 2.79 ± 0.22 mM) of the renatured protein was similar to that of the native protein purified from soybean seeds. Collectively, these results indicate that the folded structure of the renatured protein was similar to the native SBP protein. As a member of the bicupin family of proteins, which includes highly stable seed storage proteins, SBP2 was fairly stable at high temperatures. Likewise, it remained folded to a similar extent in the presence or absence of 7.6 M urea or 6.7 M GdmHCl. The high stability of the renatured protein may be a reminiscent property of SBP from its evolutionary relatedness to the seed storage proteins