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1.
Food Res Int ; 192: 114807, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39147471

RESUMO

Alternative protein sources have been required to meet the significant plant protein demand. Agro-industrial by-products such as leaves have considerable potential as a source of macromolecules once they are mostly discarded as waste. The current study evaluated dried cassava leaves as a protein source. First, alkaline extraction parameters (solid-liquid ratio, pH, and temperature) were optimized and the run that result in the highest protein yield were acidified at pH 2.5 or 4. The influence of carbohydrate solubilized on protein precipitation was also evaluated by removing it via alcoholic extraction prior to precipitation. The experimental design showed that high pH and temperature conditions associated with a low solid-liquid ratio led to increased protein yields. The presence of carbohydrates in the supernatant significantly influenced protein precipitation. The protein concentrate had around 17.51% protein when it was obtained from a supernatant with carbohydrates, while protein content increased to 26.88% when it was obtained from carbohydrate-free supernatant. The precipitation pH also influenced protein content, whereas protein content significantly decreased when pH increased from 2.5 to 4. The natural interaction between carbohydrates and proteins from cassava leaves positively influenced the emulsion stability index and the foaming capacity and stability. Thus, the presented results bring insights into challenges in extracting and precipitation proteins from agro-industrial by-products.


Assuntos
Precipitação Química , Manihot , Folhas de Planta , Proteínas de Plantas , Temperatura , Manihot/química , Folhas de Planta/química , Concentração de Íons de Hidrogênio , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/química , Emulsões/química
2.
Front Plant Sci ; 15: 1411952, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39104848

RESUMO

The use of exotic grasses of African origin for pastures in Brazil has been a major advancement in livestock production, but little is known about the responses of these grasses to nitrogen fertilizers associated with shading. In this study, the morphogenetic, structural, and leaf anatomical characteristics of Megathyrsus maximus cultivars' Tamani and Quênia were investigated as a function of N dose and shade. Morphogenetic and structural characteristics and leaf anatomy were studied under three shading levels (0, 30, and 50 %) and four N doses (0, 100, 200, and 300 kg N ha-1) to simulate growth in a silvopastoral system. When comparing the cultivars, Quênia was more efficient in terms of phyllochron up to fertilization with 100 kg N ha-1. The leaf senescence rate of Tamani was higher than that of Quênia at the 30 and 50 % shade levels. The total area (TA) occupied by leaf tissues decreased in Quênia as a function of the increase in N fertilization, whereas the TA of Tamani did not change. The thickness of the adaxial epidermis was greater in Quênia (0.68 µm) than in Tamani (0.50 µm) when not fertilized. The area occupied by the mesophyll was greater in both cultivars when they received fertilization equivalent to 300 kg N ha-1. Quênia grass has a smaller phyllochron than Tamani grass, due to the rapid reconstruction of its photosynthetic apparatus, especially when it receives higher levels of nitrogen fertilization. However, Tamani grass has a greater distribution of plant tissues. The mesophyll area is larger in Tamani grass due to the greater presence of chloroplasts, which facilitates digestion by animals. The Tamani modified the leaf anatomical tissues more significantly in relation to shading, whereas the Quênia modified them in relation to N fertilization, which reinforces the suggestion of a more appropriate use of Tamani in silvopastoral systems.

3.
HardwareX ; 19: e00557, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39108458

RESUMO

Spectral signatures allow the characterization of a surface from the reflected or emitted energy along the electromagnetic spectrum. This type of measurement has several potential applications in precision agriculture. However, capturing the spectral signatures of plants requires specialized instruments, either in the field or the laboratory. The cost of these instruments is high, so their incorporation in crop monitoring tasks is not massive, given the low investment in agricultural technology. This paper presents a low-cost clamp to capture spectral leaf signatures in the laboratory and the field. The clamp can be 3D printed using PLA (polylactic acid); it allows the connection of 2 optical fibers: one for a spectrometer and one for a light source. It is designed for ease of use and holds a leave firmly without causing damage, allowing data to be collected with less disturbance. The article compares signatures captured directly using a fiber and the proposed clamp; noise reduction across the spectrum is achieved with the clamp.

4.
Front Plant Sci ; 15: 1393796, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39109054

RESUMO

The use of wild species as a source of genetic variability is a valued tool in the framework of crop breeding. Hordeum chilense Roem. et Schult is a wild barley species that can be a useful genetic donor for sustainable wheat breeding which carries genes conferring resistance to some diseases or increasing grain quality, among others. Septoria tritici blotch (STB), caused by the Zymoseptoria tritici fungus, is one of the most important wheat diseases worldwide, affecting both bread and durum wheat and having a high economic impact. Resistance to STB has been previously described in H. chilense chromosome 4Hch. In this study, we have developed introgression lines for H. chilense chromosome 4Hch in durum wheat using interspecific crosses, advanced backcrosses, and consecutive selfing strategies. Alien H. chilense chromosome segments have been reduced in size by genetic crosses between H. chilense disomic substitution lines in durum wheat and durum wheat lines carrying the Ph1 deletion. Hordeum chilense genetic introgressions were identified in the wheat background through several plant generations by fluorescence in situ hybridisation (FISH) and simple sequence repeat (SSR) markers. An STB infection analysis has also been developed to assess STB resistance to a specific H. chilense chromosome region. The development of these H. chilense introgression lines with moderate to high resistance to STB represents an important advance in the framework of durum breeding and can be a valuable tool for plant breeders.

5.
Plant Biol (Stuttg) ; 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39141664

RESUMO

Andean ecosystems are characterized by high humidity, mainly from rain and fog events. Because of differences in altitude two Andean ecosystems - sub-Andean forest and Páramo -face different environmental pressures that affect leaf anatomy and cell wall composition and, consequently, species foliar water uptake (FWU) capacity. Here, FWU capacity of eight species in the Melastomataceae was evaluated and found to be related to proportions of cell wall components and aquaporins in the two ecosystems. Cellulose was labelled with Calcofluor white, and aquaporin and pectins were labelled with monoclonal antibodies. There were differences in plant FWU capacity in both ecosystems, with higher FWU capacity in sub-Andean forest species than in Páramo forest species. Cell wall components were positively related to FWU, with increased FWU related to pectin and aquaporin content of the plasma membrane. Differences in water availability in the two analysed environments led to differences in FWU capacity that are associated with leaf anatomical traits and cell wall composition. In these two environments, plants with similar traits are selected to respond to given environmental pressures. Traits that favour FWU in sub-Andean forest species may lead to further advances of these species in this environments.

6.
Naturwissenschaften ; 111(5): 44, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39136793

RESUMO

Galls are plant neoformations induced by specialized parasites. Since gall inducers rely on reactive plant sites for gall development, variations in abiotic factors that affect plant phenology are expected to impact the life cycle of gall inducers. To test the hypothesis that different light conditions affect both host plant and gall inducer life cycles, we studied the system Eugenia uniflora (Myrtaceae) - Clinodiplosis profusa (Cecidomyiidae), comparing plants occurring in sunny and shaded environments. We mapped phenological differences among individuals of E. uniflora occurring in the two environments and related them to the influence of luminosity on the life cycle of the gall inducer. Shade plants showed lower intensity of leaf sprouting throughout the year compared to sun-exposed plants, especially during the rainy season. Young and mature galls are synchronized with the peak of leaf sprouting at the beginning of the rainy season, lasting longer in sun-exposed plants - approximately two months longer compared to shade plants. The greater light intensity positively impacts the formation and growth of leaves and galls, with an extended period available for their induction and growth. Thus, light is an important factor for the development of gallers, considering that variations in luminosity influenced not only the phenology of the host plant, but also determined the life cycle of gall inducers. Furthermore, changes in plant-environment interactions are expected to affect the life cycle and richness of other host plant-gall inducer systems.


Assuntos
Eugenia , Luz Solar , Eugenia/fisiologia , Animais , Tumores de Planta/parasitologia , Luz , Folhas de Planta/parasitologia , Folhas de Planta/fisiologia , Estações do Ano , Interações Hospedeiro-Parasita/fisiologia , Estágios do Ciclo de Vida/fisiologia
7.
Anat Rec (Hoboken) ; 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39095996

RESUMO

Phyllostomidae, the most diverse family of Neotropical bats, encompass 230 species with varied dietary habits and food acquisition methods. Their feeding niche diversification has shaped skull and wing morphologies through natural selection, reflecting food processing and flight strategies. Yet, evolution of bat hindlimbs, especially in phyllostomids, remains little understood. Previous studies highlighted the femur's morphology as a key to understanding the evolution of quadrupedalism in yangochiropteran bats, including the adept walking observed in vampire bats (Desmodontinae). Here, we aimed to describe the femoral morphological variation in Phyllostomidae, correlating this with body size and assessing the effects of phylogenetic history, dietary habits, and hindlimb usage. Analyzing 15 femoral traits from 45 species across 9 subfamilies through phylogenetically informed methods, we discovered a significant phylogenetic structure in femoral morphology. Allometric analysis indicated that body mass accounts for about 85% of the variance in phyllostomid femoral size and about 11% in femoral shape. Relatively smaller femurs showed to be typical in Stenodermatinae, Lonchophyllinae, and Glossophaginae, in contrast to the larger femurs of Phyllostominae, Desmodontinae, Micronycterinae, and Lonchorrhininae. Furthermore, extensive femur shape variation was detected, with the most distinct morphologies in vampire bats, followed by frugivorous species. Adaptive evolutionary models related to diet more effectively explained variations in femoral relative size and shape than stochastic models. Contrary to the conventional belief of limited functional demand on bat femurs, our findings suggest that femoral morphology is significantly influenced by functional demands associated with diet and food capture, in addition to being partially structured by body size and shared evolutionary history.

8.
Tree Physiol ; 44(8)2024 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-39041710

RESUMO

Increases in hydrological extremes, including drought, are expected for Amazon forests. A fundamental challenge for predicting forest responses lies in identifying ecological strategies which underlie such responses. Characterization of species-specific hydraulic strategies for regulating water-use, thought to be arrayed along an 'isohydric-anisohydric' spectrum, is a widely used approach. However, recent studies have questioned the usefulness of this classification scheme, because its metrics are strongly influenced by environments, and hence can lead to divergent classifications even within the same species. Here, we propose an alternative approach positing that individual hydraulic regulation strategies emerge from the interaction of environments with traits. Specifically, we hypothesize that the vertical forest profile represents a key gradient in drought-related environments (atmospheric vapor pressure deficit, soil water availability) that drives divergent tree water-use strategies for coordinated regulation of stomatal conductance (gs) and leaf water potentials (ΨL) with tree rooting depth, a proxy for water availability. Testing this hypothesis in a seasonal eastern Amazon forest in Brazil, we found that hydraulic strategies indeed depend on height-associated environments. Upper canopy trees, experiencing high vapor pressure deficit (VPD), but stable soil water access through deep rooting, exhibited isohydric strategies, defined by little seasonal change in the diurnal pattern of gs and steady seasonal minimum ΨL. In contrast, understory trees, exposed to less variable VPD but highly variable soil water availability, exhibited anisohydric strategies, with fluctuations in diurnal gs that increased in the dry season along with increasing variation in ΨL. Our finding that canopy height structures the coordination between drought-related environmental stressors and hydraulic traits provides a basis for preserving the applicability of the isohydric-to-anisohydric spectrum, which we show here may consistently emerge from environmental context. Our work highlights the importance of understanding how environmental heterogeneity structures forest responses to climate change, providing a mechanistic basis for improving models of tropical ecosystems.


Assuntos
Florestas , Árvores , Água , Água/metabolismo , Água/fisiologia , Árvores/fisiologia , Brasil , Secas , Transpiração Vegetal/fisiologia , Solo/química , Folhas de Planta/fisiologia
9.
Fungal Biol ; 128(5): 1917-1932, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39059847

RESUMO

Here, we report on a Cordyceps species entering into a multi-trophic, multi-kingdom association. Cordyceps cateniannulata, isolated from the stem of wild Coffea arabica in Ethiopia, is shown to function as an endophyte, a mycoparasite and an entomopathogen. A detailed polyphasic taxonomic study, including a multilocus phylogenetic analysis, confirmed its identity. An emended description of C. cateniannulata is provided herein. Previously, this species was known as a pathogen of various insect hosts in both the Old and New World. The endophytic status of C. cateniannulata was confirmed by re-isolating it from inoculated coffee plants. Inoculation studies have further shown that C. cateniannulata is a mycoparasite of Hemileia vastatrix, as well as an entomopathogen of major coffee pests; infecting and killing Hypothenemus hampei and Leucoptera coffeella. This is the first record of C. cateniannulata from Africa, as well as an endophyte and a mycoparasite. The implications for its use as a biocontrol agent are discussed.


Assuntos
Coffea , Cordyceps , Endófitos , Filogenia , Endófitos/classificação , Endófitos/isolamento & purificação , Endófitos/genética , Endófitos/fisiologia , Cordyceps/genética , Cordyceps/classificação , Coffea/microbiologia , Coffea/parasitologia , Animais , Doenças das Plantas/microbiologia , Doenças das Plantas/parasitologia , Etiópia , DNA Fúngico/genética , DNA Fúngico/química , DNA Espaçador Ribossômico/genética , DNA Espaçador Ribossômico/química , Caules de Planta/microbiologia , Caules de Planta/parasitologia , Análise de Sequência de DNA , Análise por Conglomerados
10.
Life (Basel) ; 14(7)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-39063579

RESUMO

Bacterial leaf streak caused by Xanthomonas vasicola pv. vasculorum (Xvv) is an emerging disease in several corn-producing regions around the world. In Brazil, there is a lack of information on the survival of this bacterium in soil and crop residues. Thus, the objective of this study was to determine the survival of Xvv in soil and also in infected corn crop residues under the humid subtropical climate of southern Brazil. The survival of Xvv in soil was initially investigated in sandy and clayey soils maintained at 20, 25 and 30 °C under controlled conditions. The survival of the bacterium under field conditions was studied in artificially infested clayey soil. The survival of Xvv in corn crop residues was investigated in infected residues maintained on the soil surface or buried in the soil at 20 cm deep. Under controlled conditions, regardless of the type of soil, the bacterium survived longer at 20 °C than at higher temperatures. The bacterium survived for 40 days in clayey soil kept at 20 °C and four days in sandy soil maintained at 30 °C. Under field conditions, the survival of Xvv in the soil was only for 48 h and in infected corn crop residues for up to 15 days in the samples maintained on the soil surface. In samples of infected corn residues buried in the soil, the bacterium was only detected at the time the experiment was set up. In general, the results obtained in this study revealed that Xvv survives for a short period of time in soil and in infected corn crop residues under humid subtropical conditions. Therefore, soil and corn residues may not be highly important sources of primary inoculum for the development of bacterial leaf streak on corn crops under these conditions.

11.
Food Technol Biotechnol ; 62(2): 150-161, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39045307

RESUMO

Research background: While the use of chemical preservatives in meat may appear to be tremendously advantageous, they have long been purported to increase the risk of incidence of certain types of cancers. Consequently, many people have opted for minimally processed alternatives. This consumer shift has placed substantial pressure on the food industry to implement more natural alternatives to these synthetic preservatives in the meat industry. Research on plant extracts as potential agents for food additives is increasing. The bioactive components present in West Indian bay leaf and turmeric essential oils have a promising potential for use as novel, green preservatives in the meat industry. Experimental approach: Raw chicken breast samples (28 g) were each treated with different volumes (0.5, 1 and 1.5 mL) of the essential oil of West Indian bay leaf or turmeric or their mixture (1:1 to make up a final volume of 0.5, 1 and 1.5 mL). Physicochemical, microbiological and sensory evaluations were performed on the fresh and treated samples stored for 14 days at 4 °C. Results and conclusions: The West Indian bay leaf oil had a higher extraction yield and total phenolic content, while the turmeric oil had a higher total flavonoid content. The most effective treatments, compared to the control, significantly (p<0.05) minimized the pH increase by 13.9 % (1.5 mL bay leaf oil), reduced texture loss by 44.8 % (1.5 mL oil mixture) and reduced protein loss by 98.9 % (1 mL bay leaf oil). Most treated samples had reduced microbial loads, with the turmeric oil showing the highest efficacy against lactic acid bacteria, yeasts and moulds. Treated samples had significantly higher (p<0.05) sensory scores than the control on the final day of storage, with the 1.5 mL oil mixture proving to be the most effective, as the storage life of the chicken breast sample was extended by 6 days. Novelty and scientific contribution: This study has shown for the first time that the essential oil from turmeric and West Indian bay leaf can extend the shelf life of raw chicken breast and highlights the potential of the oil as natural preservative agents in lieu of synthetic alternatives.

12.
Pest Manag Sci ; 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39082239

RESUMO

BACKGROUND: Managing pest species of eusocial insects, such as leaf-cutting ants, poses significant challenges. Controlling them requires understanding of how toxic plant substrates and ant baits are recognized by foragers, transported to the nest, shared among workers and managed by gardeners cultivating the symbiont fungus garden. Despite this, little is known about how unsuitable resources might impact social interactions within ant colonies. This study aims to investigate whether the provision of a suitable substrate (copperleaf) and a toxic substrate (nasturtium leaves) affects the social network dynamics within colonies of two leaf-cutting ant species: Acromyrmex molestans and Acromyrmex subterraneus. The interactions between castes were recorded and subjected to social network analyses. RESULTS: Initial foraging duration increased for A. subterraneus provided with copperleaf, although no difference was observed for the other species and resource combinations. The social network structure was similar for both species when copperleaf leaves were provided as a substrate. However, notable alterations occurred with nasturtium leaf provision, leading to higher integration of gardeners in interactions and noticeable changes in the generalist worker network centrality, particularly in A. subterraneus. DISCUSSION: The observed changes in social interactions, particularly in A. subterraneus, suggest that increasing gardener interactions with other castes expedites the movement of the substrate within the colony. This maximizes the potential toxic effect on the colony. © 2024 Society of Chemical Industry.

13.
Neotrop Entomol ; 53(5): 1137-1148, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39026134

RESUMO

Herbivorous insects depend on the host plant to optimize their overall reproductive success, and balanced fertilization may alter the plant's quality against herbivory. Life history traits of the Liriomyza trifolii (Burgess) were determined under laboratory conditions using either unfertilized and fertilized plants of bean [Phaseolus vulgaris L. (Fabaceae)], chrysanthemum [Chrysanthemum × morifolium (Asteraceae)], potato [Solanum tuberosum (Solanaceae)], bell pepper [Capsicum annuum (Solanaceae)], and tomato [Solanum lycopersicum (Solanaceae)]. Results indicated that L. trifolii completed development on all studied unfertilized and fertilized plants. Nevertheless, a higher performance of the leaf miner was observed on bean and bell pepper plants compared to the other plants. Furthermore, there was an interaction of the host plant and fertilization with Calcium Aria or Sitam negatively affecting the fitness-related traits of the leaf miner. Application of these fertilizers resulted in delayed immature development of L. trifolii, decreased survival rate, and reduced adult longevity and fecundity. The activity of cinnamyl alcohol dehydrogenase (CAD), peroxidase (POD), polyphenol oxidase (PPO), and phenylalanine ammonia-lyase (PAL) enzymes, as well as phenolic, flavonoid, and lignin content were higher in Calcium Aria + Sitam fertilized plants, intermediate in Calcium Aria and Sitam treated plants, and the lower in unfertilized plants. The development and survival of L. trifolii on different host plants, considering fertilization options, become important for deploying cultural control practices against this important pest species.


Assuntos
Dípteros , Herbivoria , Animais , Dípteros/fisiologia , Phaseolus , Chrysanthemum , Fertilizantes , Características de História de Vida , Capsicum , Larva/crescimento & desenvolvimento , Solanum tuberosum , Feminino , Solanum lycopersicum , Longevidade , Fertilidade , Masculino
14.
Neotrop Entomol ; 53(4): 715-725, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38955944

RESUMO

Several crops depend on both managed and wild bees to produce fruits and/or seeds, and the efficiency of numerous wild bees is higher than that of some managed species. Therefore, knowing and understanding the required resources for wild bees could enabled the establishment of management practices to increase their populations. Here, we provide information about the nesting biology of Megachile (Chrysosarus) jenseni, a Faboideae-specialist bee species. Based on observations from two populations occurring in contrasting agroecosystems, this bivoltine species showed common behavioral features shared with other species of subgenus Chrysosarus, such as the use of petal pieces and mud as nesting materials and the utilization of pre-existing cavities. Both studied populations showed a bivoltine life cycle with a rapid early-summer generation and a second generation, with most individuals overwintering. Main causes of mortality were unknown diseases (or other factors), causing the death of preimaginal stages. Moreover, this species was attacked by a cleptoparasite megachilid (Coelioxys remissa), a parasitic eulophid wasp (Melittobia sp.), and a bee fly (Anthrax oedipus). Finally, we discussed the potential use of this leaf-cutter bee species for alfalfa pollination.


Assuntos
Medicago sativa , Comportamento de Nidação , Polinização , Animais , Abelhas/fisiologia , Feminino , Vespas/fisiologia , Brasil , Estações do Ano
15.
J Econ Entomol ; 117(5): 1703-1711, 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39023256

RESUMO

Social insect pests, particularly leaf-cutting ants, present a considerable challenge in terms of control. Leaf-cutting ants are significant agricultural, forestry, and pasture pests, and understanding their behavior and defense mechanisms is essential for managing their colonies effectively. While toxic ant baits are a primary control method, the limited availability of effective insecticides and concerns over their hazardous nature has spurred the search for alternative solutions, particularly natural compounds, which aligns with the goals of forest certification groups. In the light of previous evidence demonstrating the efficacy of nasturtium leaves (Tropaeolum majus L. (Brassicales: Tropaeolaceae)) in suppressing leaf-cutting ant colonies, this study investigates 2 active components of nasturtium leaf extracts: diphenyl disulfide and lyral. We tested their impact on Atta sexdens (L.) (Hymenoptera: Formicidae), the most prevalent leaf-cutter ant species in Brazil, and their symbiotic fungus, Leucoagaricus gongylophorus (Möller) Singer (Agaricales: Agaricaceae). We conducted experiments with increasing concentrations of diphenyl disulfide and lyral, assessing their effects on the symbiotic fungus and on forager workers and gardeners of A. sexdens colonies. Our findings revealed no fungicidal activity, and ant mortality was minimal in both topical and ingestion bioassays with the exception of gardeners topically exposed to diphenyl sulfide. Furthermore, the compounds did not affect leaf ingestion, but diphenyl disulfide did increase interactions among foragers. These results suggest that neither diphenyl disulfide nor lyral are the primary contributors to the suppression of leaf-cutting ant colonies by nasturtium leaves. However, they may enhance the formicidal activity of other compounds present in nasturtium leaves.


Assuntos
Formigas , Inseticidas , Folhas de Planta , Animais , Simbiose , Controle de Insetos , Extratos Vegetais/farmacologia
16.
Ann Bot ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39021206

RESUMO

BACKGROUND: In epiphytic bromeliads, the roots used to be considered poorly functional organs in the processes of absorption and metabolization of water and nutrients, while the leaves always acted as protagonists in both functions. More recent discoveries have been changing this old view of the root system. SCOPE: In this review, we will address the old thoughts of the scientific community regarding the function performed by the roots of epiphytic bromeliads (mere holdfast structures with low physiological activity) and the importance of a reduced or lack of root system for the emergence of epiphytism. We will present indirect and direct evidence that contradicts this older hypothesis. Furthermore, the importance of the root absorptive function mainly for juvenile tankless epiphytic bromeliads and the characteristics of the root absorption process of adult epiphytic tank bromeliads will be thoroughly discussed in physiological aspects. Finally, some factors (species, substrate, environmental conditions) that influence the absorptive capability of the roots of epiphytic tank bromeliads will also be considered in this review, highlighting the importance that the absorptive role of the roots have for the plasticity of bromeliads that live on trees, which is an environment characterized by the intermittent availability of water and nutrients. CONCLUSIONS: The roots of tank-forming epiphytic bromeliads play important roles in the absorption and metabolization of nutrients and water. The importance of roots stands out mainly for juvenile tankless bromeliads since the root is the main absorptive organ. In larger plants with tank, although the leaves become the protagonists in the resource acquisition process, the roots complement the absorptive function of the leaf trichomes, resulting in a better growth of the bromeliad. The physiological and biochemical properties of the processes of absorption and distribution of resources in the tissues seem to differ between absorption by trichomes and roots.

17.
Plant Dis ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39010655

RESUMO

Melon (Cucumis melo L.) is an economically important crop in Brazil, with an annual production of 699.281 tons (FAO 2024). Fungal diseases are one of the biggest problems in melon production, and melon growers in northeastern Brazil have reported over 80% of plants showing anthracnose symptoms in the fields during rainy seasons. Plants were wilted, displaying brown necrotic lesions and water-soaked spots with yellowish edges on the leaves and vines. Melon fruits displayed necrotic lesions on the outside. From June 2022 to June 2023, melon leaves (varieties Yellow, Galia, and Cantaloupe) from anthracnose-symptomatic plants were collected in four melon farms located in the municipalities of Afonso Bezerra, Mossoró, Tibau, and Upanema in the state of Rio Grande do Norte. Small fragments of symptomatic leaves were disinfected in 70% ethanol (30 sec) and 2.5 % sodium hypochlorite (1 min), rinsed in sterile distilled water, and plated on PDA Petri dishes with tetracycline (0.05g/liter). Plates were maintained in a bio-oxygen demand incubator (BOD) for 3 days at 28 ± 2 °C, under a 12 hr photoperiod. Eleven representative fungal colonies resembling Colletotrichum spp. were selected and monosporically grown on PDA for seven days for morphology, pathogenicity, and molecular analyses.ight colonies showed pinkish-dark brown with acervuli in the center and cottony mycelium, and showing black edges in some isolates, resembling C. plurivorum (Zhang et al. 2023). Conidia from those colonies were hyaline, cylindrical with obtuse ends, and 17.76 x 7.06 µm, n= 50. Three colonies developed pinkish-gray mycelia with numerous black microsclerotia, and the conidia were hyaline, falcate, and 27.38 x 4.10 µm, n= 50, resembling C. truncatum (Yu et al. 2023). The total DNA of the eleven isolates was extracted, and the internal transcribed space (ITS), glyceraldehyde 3-phosphate dehydrogenase (GAPDH), actin (ACT), ß-tubulin (TUB), and chitin synthase 1 (CHS-1) regions were partially amplified by PCR. Amplicons were sequenced and deposited to Genbank (Table eXtra1). A phylogenetic tree was built with the Maximum likelihood method with the concatenated sequences of the five partial gene sequences on Software MEGA (Version 11.0.10) (Tamura et al. 2021). The isolates CML5, CML8, CML9, CML10, CML11, CML14, CML15, and CML25 were grouped with Colletotrichum plurivorum CBS 125474 (orchidearum complex), and the isolates CML26, CML27 and CML28 with Colletotrichum truncatum CBS 15:35 (truncatum complex) with 87 % e 97 % of Bootstrap support, respectively. C. plurivorum was detected in four farms visited (we selected two representative isolates per farm), while C. truncatum isolates were all from the farm in Afonso Bezerra municipality. A pathogenicity test was performed following the method of Baishuan et al. (2023), micro-injuries were made in leaves of melon seedlings 'Goldex Yellow' and inoculated with a spore suspension of colonies with seven days of growth (106 spore/mL) of each isolate and sprayed to the point of dripping. Sterile water was used as mock. After nine days, anthracnose symptoms similar to those observed in the field were seen in all inoculated leaves, while no symptom was observed in the leaves of the mock plants. The pathogens were reisolated and their identification was confirmed by morphology and sequencing. Five seedlings were inoculated per isolate and mock, the assay was repeated, and the same results were observed. The species C. plurivorum has already been reported to cause disease in Cucumbers in Brazil (Silva et al. 2023) and C. plurivorum and C. truncatum in Citrullus lanatus in China (Guo et al. 2022). To the best of our knowledge, this is the first report of C. plurivorum and C. truncatum causing anthracnose in melon plants in Brazil.

18.
Int J Phytoremediation ; : 1-12, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39008081

RESUMO

Soil salinity is a significant abiotic stress and poses risks to environmental sustainability. Thus, the improvement of the time for recovering the salt-affect soil is crucial for the phytoextraction process using halophytes plants, especially regarding on nutritional management. We evaluated the responses of Atriplex nummularia Lindl. to nitrogen (N) and phosphorus (P) under different salinity levels. The treatments comprised doses of N (N1 = 80 kg ha-1) and P (P1 = 60 kg ha-1): (1) without N and P (N0P0) (control); (2) with N and without P (N1P0); (3) without N and with P (N0P1); and (4) with N and P (N1P1) and five levels of electrical conductivity from irrigation water: 0.08, 1.7, 4.8, 8.6, and 12.5 dS m-1. The. We evaluated dry biomass of leaves, stems, and roots 93 days after transplantation. We also assessed the leaf and osmotic water potential, the osmotic adjustment, and the nutrient contents (N, P, Na, and K). N application increased 22.3, 17.8, and 32.8% the leaf biomass, stem biomass, and osmotic adjustment, respectively; and consequently, boosts Na extraction in 27.8%. Thus, the time of the phytoextraction process can be improved with N fertilizer at a rate of 80 kg ha-1.


Very few studies have investigated the nutrient dynamics responses in Atriplex species in salt-affected soils; thus, this study represents a novelty. We tested the management of nitrogen (N) and phosphate (P) fertilizers to increase crop yield and optimize the phytoextraction process in salt-affected soils. We believe our results contribute to the improvement of the knowledge of this relevant topic, mainly in terms of the recovery of areas degraded by salinity. There is a paucity of studies associating salinity and nutritional management of soils worldwide.

19.
Molecules ; 29(13)2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38998936

RESUMO

Metabolic alterations are increasingly recognized as important aspects of colorectal cancer (CRC), offering potential avenues for identifying therapeutic targets. Previous studies have demonstrated the cytotoxic potential of bamboo leaf extract obtained from Guadua incana (BLEGI) against HCT-116 colon cancer cells. However, the altered metabolic pathways in these tumor cells remain unknown. Therefore, this study aimed to employ an untargeted metabolomic approach to reveal the metabolic alterations of the endometabolome and exometabolome of HCT-116 cells upon exposure to BLEGI treatment. First, a chemical characterization of the BLEGI was conducted through liquid chromatography coupled with mass spectrometry (LC-MS). Next, we assessed cell viability via MTT and morphological analysis using an immunofluorescence assay against colon cancer cells, and anti-inflammatory activity using an LPS-stimulated macrophage model. Subsequently, we employed LC-MS and proton nuclear magnetic resonance (1H-NMR) to investigate intra- and extracellular changes. Chemical characterization primarily revealed the presence of compounds with a flavone glycoside scaffold. Immunofluorescence analysis showed condensed chromatin and subsequent formation of apoptotic bodies, suggesting cell death by apoptosis. The results of the metabolomic analysis showed 98 differential metabolites, involved in glutathione, tricarboxylic acid cycle, and lipoic acid metabolism, among others. Additionally, BLEGI demonstrated significant nitric oxide (NO) inhibitory capacity in macrophage cells. This study enhances our understanding of BLEGI's possible mechanism of action and provides fresh insights into therapeutic targets for treating this disease.


Assuntos
Neoplasias do Colo , Extratos Vegetais , Folhas de Planta , Humanos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Folhas de Planta/química , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Células HCT116 , Metabolômica/métodos , Metaboloma/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Animais , Células RAW 264.7 , Camundongos , Cromatografia Líquida
20.
Plants (Basel) ; 13(13)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38999661

RESUMO

Plant density is increasing in modern olive orchards to improve yields and facilitate mechanical harvesting. However, greater density can reduce light quantity and modify its quality. The objective was to evaluate plant morphology, biomass, and photosynthetic pigments under different red/far-red ratios and photosynthetically active radiation (PAR) combinations in an olive cultivar common to super-high-density orchards. In a greenhouse, young olive trees (cv. Arbequina) were exposed to low (L) or high (H) PAR with or without lateral FR supplementation (L+FR, L-FR, H+FR, H-FR) using neutral-density shade cloth and FR light-emitting diode (LED) modules. Total plant and individual organ biomass were much lower in plants under low PAR than under high PAR, with no response to +FR supplementation. In contrast, several plant morphological traits, such as main stem elongation, individual leaf area, and leaf angle, did respond to both low PAR and +FR. Total chlorophyll content decreased with +FR when PAR was low, but not when PAR was high (i.e., a significant FR*PAR interaction). When evaluating numerous plant traits together, a greater response to +FR under low PAR than under high PAR appeared to occur. These findings suggest that consideration of light quality in addition to quantity facilitates a fuller understanding of olive tree responses to a light environment. The +FR responses found here could lead to changes in hedgerow architecture and light distribution within the hedgerow.

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