Browsing by Author "Isaias, Rosy Mary dos Santos"

Now showing 1 - 7 of 7
  • No Thumbnail Available
    Item
    Apoplast-symplast compartmentalization and functional traits of iron and aluminum in promeristematic tissues of nematode induced galls on Miconia spp.
    (2020) Arriola, Igor Abba; Figueiredo, Maurílio Assis; Souza, Daniela Boanares de; França, Marcel Giovanni Costa; Isaias, Rosy Mary dos Santos
    The nutritive tissues of galls induced by Ditylenchus gallaeformans (Nematoda) have promeristematic capacity, which may turn these galls into sinks of Al on their Melastomataceae Al-accumulating hosts. Such a sink of Al may affect gall growth and mineral nutrient intake. Based on the fact that galls are good models for plant developmental studies, we aimed to understand how Al-accumulating host plants in the Cerrado environment deal with Al toxicity in subcellular levels. Here, we used the ICP-OES method to check the variations on mineral nutrients, and the morin, hematoxylin, and Prussian blue stainings for Al and Fe histolocalization in galls induced on four Miconia species of the Brazilian Cerrado. We confirmed the new Al-accumulating feature for two Miconia species of the Cerrado environment. Furthermore, we found that Al accumulates in lesser concentrations in gall tissues than in non-galled tissues of the Miconia hosts. Staining methods indicated that the polyphenols avoid Albinding to the apoplast and the nucleolus of the promeristematic cells, and mediated its binding to parenchyma cell walls. As well, we inferred that Fe3þ is transported by xylem and stored in gall parenchyma, where it is reduced to Fe2þ, being available in gall nutritive cells. Our results demonstrated an Al compartmentalization between the apoplast and symplast of the inner cell layers in galls, as well as indicated the phenolics action against Al-toxicity and toward Fe availability for the diet of Ditylenchus gallaeformans.
  • No Thumbnail Available
    Item
    Atributos funcionais morfológicos e anatômicos foliares de plantas de campo rupestre ferruginoso respondem abundancia?
    (2017) Eduardo, Denny Fernandes; Sousa, Hildeberto Caldas de; Kozovits, Alessandra Rodrigues; Sousa, Hildeberto Caldas de; França, Marcel Giovanni Costa; Isaias, Rosy Mary dos Santos
    Atributos funcionais foliares são utilizados para um melhor esclarecimento sobre as adaptações que cada espécie tem em cada ambiente específico, e podem indicar quais características são mais importantes em espécies mais e menos abundantes em um determinado espaço e tempo. Diferentes histórias de vida das plantas podem ter sucesso em um mesmo espaço e tempo, podendo selecionar adaptações distintas com relação à economia de água, e sua aquisição e manutenção pelas folhas. Os campos rupestres ferruginosos são ambientes montanos que ocorrem acima de 900m e impõem severidade ambiental nas plantas por estresse hídrico devido à marcada estação seca, alta radiação, exposição a ventos e a ocorrência de solos rasos. É comum a ocorrência de neblina durante o ano todo, e as plantas podem absorver água pelas folhas quando ocorrem este evento o qual pode influenciar nos níveis de esclerofilia das folhas. Para analisar as adaptações que as plantas possuem neste tipo de ambiente, foram selecionadas cinco espécies mais abundantes, Tibouchina heteromalla, Baccharis reticularia, Diplusodon buxifolius, Periandra mediterranea e Erytroxylum mirophyllum, e cinco menos abundantes Myrsine squarrosa, Miconia coralina, Eremanthus incanus, Ouratea semiserrata e Trembleya laniflora, a partir do trabalho de (Arias 2016). E foram analisados a área foliar, área foliar específica, massa foliar específica, espessura do limbo foliar, espessura da cutícula, espessura da epiderme adaxial, espessura do parênquima paliçádico, espessura do parênquima lacunoso, espessura da epiderme abaxial, espessura da cutícula abaxial, densidade e área estomática. As espécies mais abundantes apresentaram áreas foliares reduzidas, maiores valores de área foliar específica, menores valores de massa foliar específica, menor espessura do limbo foliar, menor espessura da cutícula adaxial, maiores células epidérmicas na face adaxial, menor espessura do parênquima lacunoso, maior espessura da epiderme abaxial e menor espessura da cutícula abaxial, maior densidade estomática e também maiores valores de área estomática. Além disso, T. heteromalla, B. reticularia e D. buxifolius são anfiestomáticas tais características podem melhorar o desempenho fotossintético, refletindo na maior produtividade e crescimento das plantas mais abundantes. Em outro contexto, as espécies apresentaram convergência evolutiva em atributos que favorecem a absorção de água e manutenção nas folhas quando ocorrem eventos de neblina, como pubescência pesada e células mucilaginosas, além de atributos que podem estar relacionados à diminuição da temperatura da folha, como drusas de oxalato de cálcio. Indicando que a neblina é um fator muito importante na seleção das espécies que ocorrem nos campos rupestres ferruginosos. Palavras chave: Atributos funcionais foliares, área foliar específica, massa foliar especifica, anatomia foliar, atributos que podem estar relacionados com a absorção de água nas folhas.
  • No Thumbnail Available
    Item
    Cuticular wax composition contributes to different strategies of foliar water uptake in six plant species from foggy rupestrian grassland in tropical mountains.
    (2021) Souza, Daniela Boanares de; Bueno, Amauri Pires; Souza, Aline Xavier de; Kozovits, Alessandra Rodrigues; Sousa, Hildeberto Caldas de; Pimenta, Lúcia Pinheiro Santos; Isaias, Rosy Mary dos Santos; França, Marcel Giovanni Costa
    The cuticle is the outermost region of the epidermal cell wall of plant aerial organs. The cuticle acts as a two-way lipid barrier for water diffusion; therefore, it plays a vital role in foliar water uptake (FWU). We hypothesised that the chemical composition of the cuticular waxes influences the FWU strategy that plants adopt in a foggy tropical ecosystem. We analysed the leaf cuticular waxes of six plant species known by their different FWU strategies, in both qualitative and quantitative approaches, to test this hypothesis. We also investigated the fine structure of the plant cuticle by scanning electron microscopy. Neither the total wax loads nor the amounts of single wax compound classes correlated to the FWU. In contrast, the qualitative chemical composition of the cuticular waxes was related to the water absorption speed but not to the maximum water absorbed. The presence of wax crystals might interfere with the FWU. Our findings suggest that a complex three-dimensional network of the cuticular compounds contributes to different strategies of FWU in six plant species from foggy tropical mountaintops.
  • No Thumbnail Available
    Item
    Foliar water‐uptake strategies are related to leaf water status and gas exchange in plants from a ferruginous rupestrian field.
    (2019) Souza, Daniela Boanares de; Kozovits, Alessandra Rodrigues; Lemos Filho, José Pires de; Isaias, Rosy Mary dos Santos; Solar, Ricardo Ribeiro de Castro; Duarte, Alexandre A.; Silva, Tiago Vilas Boas da; França, Marcel Giovanni Costa
    Premise Fog is a frequent event in Brazilian rupestrian field and plays an important role in the physiology of several plant species. Foliar water uptake (FWU) of fog may be fast or slow depending on the species. However, fog water may negatively affect CO2 assimilation. Thus, the interference in the water and carbon balance as a result of different strategies of FWU was evaluated to verify whether fog may mitigate possible water deficit in leaves. Methods Four plant species with different FWU strategies were studied in a ferruginous rupestrian field with frequent fog. Gas exchange and water potential were measured before dawn and at midday during the dry and rainy seasons, separating foggy from non‐foggy days during the dry season. Results The FWU speed negatively influences CO2 assimilation in the dry season, possibly because of its negative relationship with stomatal conductance, since reduced stomatal aperture impairs carbon entrance. Fog presence increased leaf water potential both in early morning and midday during the dry season. However, during the rainy season, the values of leaf water potential were lower at midday, than during the dry season with fog at midday, which favors leaf gas exchanges. Conclusions FWU interferes negatively, but briefly with CO2 assimilation. Nevertheless, FWU prevents water loss through transpiration and increases the water status of plants in the dry season. That is, FWU results in a compensation between CO2 assimilation and foliar hydration, which, in fact, is beneficial to the plants of this ecosystem.
  • No Thumbnail Available
    Item
    Pectin and cellulose cell wall composition enables different strategies to leaf water uptake in plants from tropical fog mountain.
    (2018) Souza, Daniela Boanares de; Ferreira, Bruno Garcia; Kozovits, Alessandra Rodrigues; Sousa, Hildeberto Caldas de; Isaias, Rosy Mary dos Santos; França, Marcel Giovanni Costa
    Leaf water uptake (LWU) has been observed in plants of different ecosystems and this process is distinct among different species. Four plant species from the Brazilian fog mountain fields were evaluated in order to detect if leaf water uptake capacity is related to the cell wall composition of leaf epidermis. LWU measurements and their relation to anatomical and biochemical traits were analyzed. Cell wall composition was verified through immunocytochemistry using monoclonal antibodies recognizing pectin compounds, and histochemistry with calcofluor white to track cellulose. Differences in LWU among the four species were clearly revealed. Two species presented higher maximum leaf water content and the lowest values of water absorption speed. The other two species presented opposite behavior, namely, low leaf water uptake and the highest values of water absorption speed. The anatomical traits associated with the cell wall composition corroborated the data on the different LWU strategies. The species with abundant detection of cellulose in their epidermal cell walls absorbed more water, but more slowly, while those with abundant detection of pectins absorbed water at a higher speed. These results indicate that cell wall composition regarding pectin and cellulose are significant for water uptake by the leaf epidermis. Pectin provides greater porosity and absorption speed, while cellulose provides greater hydrophilicity and greater water uptake capacity. Current data indicate that the composition of epidermal cell walls is a relevant trait for leaf water uptake.
  • No Thumbnail Available
    Item
    Revisão sobre as relações de regulação entre os diferentes tipos de micorrizas e orquídeas.
    (2021) Lovestain, Hikari Shin; Sousa, Hildeberto Caldas de; Borges, Cristina Machado; Sousa, Hildeberto Caldas de; Isaias, Rosy Mary dos Santos; Oliveira, Denis Coelho de
    As orquídeas apresentam uma relação de total dependência com os fungos durante sua fase de germinação. Essa relação tão íntima entre fungo e planta exige uma regulação muito fina, que impacta na fisiologia e anatomia de ambos. As orquídeas possuem associações micorrízicas com fungos que possuem ação patogênica em outras plantas e isso exige delas uma série de adaptações para lidarem com essa patogenicidade e desfrutarem dos benefícios da associação. O presente trabalho visa sistematizar a visão mais recente sobre as relações de regulação entre orquídea e fungo e as implicações dos diferentes estilos de vida.
  • No Thumbnail Available
    Item
    Strategies of leaf water uptake based on anatomical traits.
    (2018) Souza, Daniela Boanares de; Isaias, Rosy Mary dos Santos; Kozovits, Alessandra Rodrigues
    The ability of leaves to absorb fog water can positively contribute to the water and carbon balance of plants in montane ecosystems, especially in periods of soil water deficit. However, the ecophysiological traits and mechanisms responsible for variations in the speed and total water absorption capacity of leaves are still poorly known. • This study investigated leaf anatomical attributes of seven species occurring in seasonal tropical high-altitude ecosystems (rocky outcrop and forest), which could explain differences in leaf water uptake (LWU) capacities. We tested the hypothesis that different sets of anatomical leaf attributes will be more marked in plant individuals living under these contrasting environmental conditions. Anatomical variations will affect the initial rate of water absorption and the total storage capacity, resulting in different strategies for using the water supplied by fog events. • Water absorption by leaves was inferred indirectly, based on leaf anatomical structure and visual observation of the main access routes (using an apoplastic marker), the diffusion of water through the cuticle, and non-glandular or glandular trichomes in all species. • The results suggest that three LWU strategies coexist in the species studied. The different anatomical patterns influenced the speed and maximum LWU capacity. The three LWU strategies can provide different adaptive advantages to adjust to temporal and spatial variations of water availability in these tropical high-altitude environments.