Phenotypic plasticity rather than ecotypic differentiation explains the broad realized niche of a Neotropical orchid species.

Local adaptation is common in plant species, and knowing whether a population is locally adapted has fundamental and applied relevance. However, local adaptation in tropical plants remains largely less studied, and covering this gap is not simple since reciprocal transplantation - the gold standard for detecting local adaptation - is not feasible for most species. Here, we combined genetic, climatic and phenotypic data to investigate ecotypic differentiation, an important aspect of local adaptation, in coastal and inland populations of the orchid Epidendrum fulgens Brongn., a long-lived tropical plant for which reciprocal transplantation would not be feasible. We used nine microsatellite markers to estimate genetic divergence between inland and coastal populations. Moreover, occurrence data and climate data were used to test for differences in the realized niche of those populations. Finally, we assessed saturated water content, leaf specific area, height, and stomatal density in common garden and in situ to investigate the effects of ecotypic differentiation and plasticity on the phenotype. Coastal and inland groups' niches do not overlap, the former occupying a wetter and warmer area. However, this differentiation does not seem to be driven by ecotypic differentiation since there was no positive correlation between genetic structure and climate dissimilarity. Moreover, specific leaf area and leaf saturated water content, which are important phenotypic traits related to soil fertility and drought stress, were rather plastic. We conclude that ecotypic differentiation is absent, since phenotypic plasticity is an important mechanism explaining the niche broadness of this species.

Secretory structures in Baccharis platypoda DC. inflorescences (Asteraceae) and characterization of the chemical composition of its secretion.

Rocky outcrop environments at high altitudes have nutrient-poor soil, where species are exposed to water scarcity and high solar radiation. Baccharis platypoda DC. occurs in such an environment and has a rigid and transparent secretion that covers the entire inflorescence. We analysed and compared the secretory structures and their chemical composition in female and male inflorescences of B. platypoda, a dioecious species, to explore chemodiversity within this species and assess potential differences between individuals. Our investigation also aims to understand the occurrence of these substances in the genus Baccharis L. Chemical compounds and secretory structures were similar in female and male inflorescences. There are glandular trichomes on the epidermis of the abaxial surface of bracts, and secretory ducts in the axis of the inflorescence, as well as in sepals, petals, and bracts. Histochemical tests were positive for phenolic compounds, flavonoids, proteins, pectin, and lipids, but not for mucilage. Flavonoid content varied between 6.24% and 9.81%, being higher in female inflorescences. Chromatography revealed the presence of several phenolic compounds, some terpenes, and other less frequent classes in both female and male inflorescences. We highlight that trichomes found on these surfaces produce abundant phenolic compounds. These act as natural defence agents, absorbing UV radiation and minimizing oxidative stress to plant cells. The chemical composition of the secretion covering the inflorescences may reflect adaptation and survival mechanisms of these organisms under extreme sun exposure.

Minerais séricos, características morfométricas ósseas e deposição de minerais ósseos de frangos de corte alimentados com dieta com inclusão de bentonita / Serum minerals, bone morphometric characteristics and deposition of bone minerals from broilers fed diet containing bentonite

O objetivo deste trabalho foi avaliar a concentração sérica de cálcio, cloretos, ferro, fósforo e magnésio, as características morfométricas ósseas e a deposição de cálcio e fósforo nas tíbias de frangos de corte recebendo dieta com zero, 0,25 ou 0,50% de bentonita. Um ensaio foi conduzido com 288 frangos de corte de 14 a 21 dias de idade, submetidos a três dietas experimentais: sem inclusão (0,0); com inclusão de 0,25 e com inclusão de 0,50% do adsorvente bentonita. Não foram observadas diferenças (P>0,05) no desempenho das aves, nos níveis séricos de cálcio, cloretos, ferro e magnésio, no entanto os níveis de fósforo foram reduzidos (P<0,05) nas aves que ingeriram dieta com 0,50% de bentonita. Em relação às tíbias, observou-se redução (P<0,05) na matéria mineral (g e %) e no teor de cálcio com a inclusão de 0,50% de bentonita. Houve redução (P<0,05) nos níveis de fósforo das tíbias com a inclusão de 0,25 e 0,50% de bentonita. Conclui-se que a inclusão de até 0,50% do adsorvente de micotoxinas bentonita na dieta de frangos de corte não altera o desempenho zootécnico das aves. A inclusão de 0,25% de bentonita, na dieta de frangos de corte, não altera a concentração dos minerais séricos e a deposição de minerais nas tíbias, entretanto a inclusão de 0,5% reduz os níveis séricos de fósforo, o teor de matéria mineral e a concentração de cálcio e fósforo ósseos, sem afetar as características morfométricas ósseas.(AU)

The aim of this study was to evaluate performance, serum concentration of calcium, chloride, iron, magnesium, phosphorus, and bone characteristics, ash, calcium, and phosphorus in tibias of broilers receiving diet with zero, 0.25 or 0.50% of bentonite. No differences were found on performance of poultry, on serum mineral calcium, chloride, iron, magnesium, however phosphorus levels of broilers fed on diets containing 0.5% bentonite was reduced. With respect to tibia, reduction was observed on mineral matter (g and %) and calcium levels with inclusion of 0.50% bentonite, and reduction on phosphorus levels with inclusion of 0.25 or 0.50% of bentonite on diet. We conclude that the inclusion of up to 0.50% of mycotoxin adsorbent bentonite in diet of broiler does not change broiler performance. The inclusion of 0.25% of bentonite in diet of broiler does not change serum mineral concentration and mineral deposition; however, the inclusion of 0.5% decrease serum levels of phosphorus, the content of bone mineral matter, with not effects on bone morphometric characteristics.(AU)

Capacidade de enraizamento de estacas de Maytenus muelleri Schwacke com a aplicação de ácido indol butírico relacionada aos aspectos anatômicos / Rooting capacity of Maytenus muelleri Schwacke cuttings with indolebutyric acid application related to anatomical aspects

A espinheira-santa (Maytenus muelleri - Celastraceae) é a planta medicinal nativa do Sul do Brasil, cujas folhas são tradicionalmente utilizadas pela medicina popular para o tratamento de úlceras e outros problemas gástricos. Existem poucos trabalhos publicados sobre a produção de mudas e técnicas de propagação vegetativa da espécie. A propagação de espinheira-santa por estaquia poderia ser um método eficiente para obtenção de material homogêneo, com características genéticas desejáveis, produzido a partir de plantas matrizes selecionadas. O presente trabalho teve por objetivo estudar os efeitos da aplicação de ácido indol butírico (AIB), em solução e em pó, no enraizamento de estacas de espinheira-santa coletadas nas quatro estações do ano (abril/2005 a janeiro/2006), bem como averiguar, por meio de análises anatômicas e histoquímicas das estacas, a presença de possíveis impedimentos à iniciação do enraizamento adventício. Estacas provenientes de ramos de plantas matrizes de seis anos cultivadas da Estação Experimental do Canguiri, Pinhais, PR, foram coletadas e tratadas com AIB (0, 1500, 3000 mg L-1 ou mg kg-1), em solução alcoólica (50 por cento v/v) e em talco. Aos 365 dias foram avaliadas as porcentagens de estacas enraizadas e mortas, número e comprimento médio de raízes formadas por estaca. Análises anatômicas e histoquímicas com lugol e cloreto férrico foram realizadas. A estação mais promissora para o enraizamento foi o verão/2006 com 62,50 por cento para o tratamento controle, devido à menor lignficação dos ramos no período de intenso crescimento vegetativo. O número médio de raízes formadas por estaca foi de 6,94 (solução) e o comprimento médio de raízes formadas/estaca chegou a 4,82 cm nesta mesma estação. As concentrações de AIB aplicadas não foram eficientes na indução radicial, independentemente do modo de aplicação. Foi detectada a presença de uma camada quase contínua de fibras e braquiesclereídes, a qual constitui barreira anatômica à indução radicial. Os testes histoquímicos revelaram a presença de amido e de compostos fenólicos nas estacas, em todas as estações do ano. A dificuldade ou demora no enraizamento não pode ser justificada pela falta de reservas de amido nos tecidos das estacas, mas pode ser justificada pela presença de compostos fenólicos, possivelmente do grupo dos monofenóis, que causam a degradação do AIA, interferindo negativamente na indução do enraizamento.

"Espinheira-santa" (Maytenus muelleri - Celastraceae) is a medicinal plant native to Southern Brazil, the leaves of which are traditionally used in popular medicine for the treatment of stomach ulcers and other gastric problems. There are few published studies about seedling production and vegetative propagation techniques for this species. The propagation of "espinheira-santa" by cuttings could be an efficient method to obtain homogeneous material, with desirable genetic characteristics, produced from selected mother plants. This paper aimed to study the effects of indolebutyric acid (IBA) application, in solution and in powder, on the rooting of "espinheira-santa" cuttings, collected in four seasons (April/2005 to January/2006), as well as to investigate, by means of cutting anatomical and histochemical analyses, the presence of possible impediments to adventitious rooting initiation. Cuttings from branches of six-year mother plants grown at "Estação Experimental do Canguiri", Pinhais, Paraná State, Brazil, were collected and treated with IBA (0, 1500, 3000 mg L-1 or mg kg-1) in alcoholic solution (50 percent v/v) and in powder. After 365 days, the percentages of rooted and dead cuttings, the number and mean length of roots/cutting were evaluated. Anatomical and histochemical analyses were performed with lugol and ferric chloride. The most promising season for rooting was Summer/2006, with 62.50 percent of rooting for the control treatment, due to the lesser lignification degree of branches in intense vegetative growth period. The mean number of roots/cutting was 6.94 (solution) and the mean length of roots/cutting was 4.82 cm in that same season. The applied IBA concentrations were not efficient in inducing root growth, regardless of the application method. An almost continuous layer of fibers and stone cells was detected, constituting an anatomical barrier for rooting induction. The histochemical tests revealed the presence of starch and phenolic compounds in cuttings, in all seasons. The difficulty or delay in rooting cannot be justified by the absence of starch reserve in the cutting tissues but by the presence of phenolic compounds, possibly of the group of monophenols, which cause IAA degradation, negatively affecting rooting induction.