Artigos - Biologia - FCAV

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Phytochrome and Hormone Signaling Crosstalk in Response to Abiotic Stresses in Plants
(2023-01-01) Gavassi, Marina Alves [UNESP]; Alves, Frederico Rocha Rodrigues; Carvalho, Rogério Falleiros [UNESP]; Universidade Estadual Paulista (UNESP); Federal University of Goias (UFG)
Linking plant light perception to molecular and biochemical responses, multiple signaling pathways are triggered, especially considering the participation of hormones downstream of phytochromes, the most extensively characterized plant photoreceptors. It has been shown that the interaction between phytochrome and hormones modulates plant development, from seed germination to flowering, in response to a plethora of abiotic stresses, the most worrisome factors for agricultural traits. In this chapter, we provide an overview of the interaction between the main molecular components shared between phytochrome and plant hormone signaling pathways during heat, low temperature, drought, and salt stresses, discussing interesting points which raise perspectives for plant tolerance bioengineering.
Silicon modulate the non-enzymatic antioxidant defence system and oxidative stress in a similar way as boron in boron-deficient cotton flowers
(2023-04-01) Souza Junior, Jonas Pereira de [UNESP]; Prado, Renato de Mello [UNESP]; Silva Campos, Cid Naudi; Sousa Junior, Gilmar da Silveira [UNESP]; Costa, Milton Garcia [UNESP]; de Pádua Teixeira, Simone; Gratão, Priscila Lupino [UNESP]; Universidade Estadual Paulista (UNESP); Universidade Federal de Mato Grosso do Sul (UFMS); Universidade de São Paulo (USP)
Silicon (Si) application, especially via foliar application, may be promising to attenuate oxidative damage, as Si can improve the non-enzymatic antioxidant system of cotton flowers. However, studies that address the relationship between boron (B) and Si in cotton flowers are still scarce. Therefore, this paper aimed to evaluate the effect of silicon alone and added to the borate solution applied via foliar spray on the oxidative stress; proline, carotenoid, and phenol contents; and biomass production of cotton flowers grown under moderate B deficiency. The experiment was arranged in a completely randomized design with ten replicates and the following five treatments: control (cotton plants under boron deficiency); water application (without B and Si); boron application; silicon application; and B + Si. The application of B, Si, and B + Si reduced the malondialdehyde content in cotton petals by 45%, 48%, and 59%, respectively, and in cotton anthers by57%, 64%, and 67%, respectively. The dry matter of cotton petals in the respective treatments increased by 20%, 16%, 35%, and 44%, while the dry matter of cotton anthers increased by 40%, 24%, 48%, and 53%, respectively, compared to the treatment with water only. There was a strong relationship between B content and dry matter; Si content and the contents of phenols and proline; and carotenoid content and the contents of MDA and H2O2. B deficiency can induce oxidative stress specifically in the petals and anthers of cotton, with carotenoids being the main defense mechanism in flowers, while Si is capable of strongly activating defense mechanisms from phenol and proline. In conclusion, the development of organs related to reproduction is impaired by B deficiency. In addition, the foliar application of Si and B attenuates the effects of oxidative stress on the sepals and anthers of cotton, mainly favoring the development of cotton anthers.
Biofortified Rocket (Eruca sativa) with Selenium by Using the Nutrient Film Technique
(2022-11-01) Nascimento, Carolina Seno [UNESP]; Nascimento, Camila Seno [UNESP]; Lopes, Guilherme; Carrasco, Gilda; Gratão, Priscila Lupino [UNESP]; Cecílio Filho, Arthur Bernardes [UNESP]; Universidade Estadual Paulista (UNESP); Federal University of Lavras; University of Talca
Selenium (Se) is an essential micronutrient for humans, but most foods are Se deficient, mainly because of its low content in the soil. A Se-deficient diet results in increased susceptibility to cardiovascular disease, cancer, and hyperthyroidism. Agronomic biofortification is a good alternative to increase Se in food. This study investigated the effect of Se on the growth, yield, and biofortification of the rocket. Plants were grown in a hydroponic system. Seven Se concentrations (0, 10, 20, 30, 40, 50, and 60 µM) were evaluated using sodium selenate. Growth, yield, lipid peroxidation, hydrogen peroxide content, and the enzymatic activity of catalase and ascorbate peroxidase were influenced by the Se concentration. Considering the evaluated parameters, 10–30 µM Se promoted the best results, and with 20 µM, the higher yield. Rocket plants treated with Se in the nutrient solution were biofortified, showing Se contents of 598.96 to 1437.56 mg kg−1 in the dry mass, higher than plants cultivated in a nutrient solution without Se, which presented 167.84 mg kg−1 of Se. Se concentrations of 10–30 µM in the nutrient solution were beneficial for rocket plants, while concentrations above 50 µM were toxic to the plants.
CRYPTOCHROME 1a-mediated blue light perception regulates tomato seed germination via changes in hormonal balance and endosperm-degrading hydrolase dynamics
(2023-04-01) de Oliveira, Reginaldo [UNESP]; Alves, Frederico Rocha Rodrigues; da Rocha Prado, Emilaine [UNESP]; Gomes, Letícia Danielle Longuini; Freschi, Luciano; Gaion, Lucas Aparecido; Carvalho, Rogério Falleiros [UNESP]; Universidade Estadual Paulista (UNESP); Federal University of Paraíba; Universidade de São Paulo (USP); University of Marília (UNIMAR)
Main conclusion: Blue light exposure delays tomato seed germination by decreasing endosperm-degrading hydrolase activities, a process regulated by CRY1a-dependent signaling and the hormonal balance between ABA and GA. Abstract: The germination of tomato seeds (Solanum lycopersicum L.) is tightly controlled by an internal hormonal balance, which is also influenced by environmental factors such as light. In this study, we investigated the blue light (BL)-mediated impacts on physiological, biochemical, and molecular processes during the germination of the blue light photoreceptor CRYPTOCHROME 1a loss-of-function mutant (cry1a) and of the hormonal tomato mutants notabilis (not, deficient in ABA) and procera (pro, displaying a GA-constitutive response). Seeds were germinated in a controlled chamber in the dark and under different intensities of continuous BL (ranging from 1 to 25 µmol m−2 s−1). In general, exposure to BL delayed tomato seed germination in a fluency rate-dependent way due to negative impacts on the activities of endosperm-degrading hydrolases, such as endo-β-mannanase, β-mannosidase, and α-galactosidase. However, not and pro mutants presented higher germination speed index (GSI) compared to WT despite the BL influence, associated with higher hydrolase activities, especially evident in pro, indicating that the ABA/GA hormonal balance is important to diminish BL inhibition over tomato germination. The cry1a germination percentage was higher than in WT in the dark but its GSI was lower under BL exposure, suggesting that functional CRY1a is required for BL-dependent germination. BL inhibits the expression of GA-biosynthetic genes, and induces GA-deactivating and ABA-biosynthetic genes. The magnitude of the BL influence over the hormone-related transcriptional profile is also dependent upon CRY1a, highlighting the complex interplay between light and hormonal pathways. These results contribute to a better understanding of BL-induced events behind the photoregulation of tomato seed germination.
Discrimination of morningglory species (Ipomoea spp.) using near-infrared spectroscopy and multivariate analysis
(2023-03-15) Braga, Andreísa Flores; Chiconi, Leandro Aparecido; Bacha, Allan Lopes [UNESP]; Teixeira, Gustavo Henrique De Almeida [UNESP]; Cunha Junior, Luis Carlos; Alves, Pedro Luis Da Costa Aguiar [UNESP]; Support Foundation for the Technological Research Institute of the São Paulo State; ICL Brasil; Universidade Estadual Paulista (UNESP); Federal University of Goias
The occurrence of weeds is one of the main factors limiting agricultural productivity. Studies on new techniques for the identification of these species can contribute to the development of proximal sensors, which in the future might be coupled to machines to optimize the performance of species-specific weed management. Thus, the objective of this study was to use near-infrared (NIR) spectroscopy and multivariate analysis to discriminate three morningglory species (Ipomoea spp.). The NIR spectra were collected from the leaves of the three weed species at the vegetative stage (up to five leaves), within the spectral band of 4,000 to 10,000 cm-1. The discrimination models were selected according to accuracy, sensitivity, specificity, and Youden's index and were analyzed with a validation data set (n = 135). The best results occurred when the selection of spectral bands associated with the use of preprocessing was performed. It was possible to obtain an accuracy of 99.3%, 98.5%, and 98.7% for ivyleaf morningglory (Ipomoea hederifolia L.), Japanese morningglory [Ipomoea nil (L.) Roth], and hairy woodrose [Merremia aegyptia (L.) Urb.], respectively. NIR spectroscopy associated with principal component analysis and linear discriminant analysis (PC-LDA) or partial least-squares regression with discriminant analysis (PLS-DA) can be used to discriminate Ipomoea spp.
Regulatory Role of Silicon on Growth, Potassium Uptake, Ionic Homeostasis, Proline Accumulation, and Antioxidant Capacity of Soybean Plants Under Salt Stress
(2023-01-01) Peña Calzada, Kolima [UNESP]; Calero Hurtado, Alexander [UNESP]; Olivera Viciedo, Dilier; Habermann, Eduardo; de Mello Prado, Renato [UNESP]; de Oliveira, Reginaldo [UNESP]; Ajila, Gabriela [UNESP]; Tenesaca, Luis Felipe Lata; Rodríguez, Juan Carlos; Gratão, Priscila Lupino [UNESP]; Universidade Estadual Paulista (UNESP); University of Sancti Spíritus “Jose Marti Perez” (UNISS); Federal University of Maranhão; Universidade de São Paulo (USP); Universidade Federal de Viçosa (UFV)
In this study, we investigated the regulatory roles of different vias of silicon (Si) applications on soybean biochemical, physiological, and growth responses and their effectiveness in salt stress remediation. The key mechanisms for improving growth and potassium (K+), ion homeostasis, proline content, and the enzymatic antioxidant capacity of salt-affected soybean plants (50 and 100 mmol NaCl L−1) were investigated when potassium silicate was supplied in different vias (non-Si application, foliar spraying at 20 mmol L−1, nutrient solution addition at 2.0 mmol L−1, and co-application of foliar spraying at 20 mmol L−1 and nutrient solution addition at 2.0 mmol L−1). Salt stress sharply decreased soybean growth by increasing Na+ uptake and lipid peroxidation (LPO) content in the roots and leaves. Alternatively, soybean growth, K+/Na+ ratio, proline content, and enzymatic antioxidant activity were reduced under moderate and high salinity conditions. However, different vias of Si application increased soybean tolerance to salinity stress by drastically decreasing Na+ uptake and LPO concentration, increasing K+ concentration, K+/Na+ ratio, and proline accumulation, upregulating enzymatic antioxidant activity, and increasing plant growth. As compared to other exogenous application methods, co-application foliar spraying with a nutrient solution of Si produced enhanced results. Furthermore, foliar spraying of Si is an efficient method for salt stress remediation. The present study indicated that Si improved soybean growth by enhancing K+ and proline content, and that antioxidant capacity could be used as a mitigation strategy against salinity stress-related damages.
Action of silicon on the activity of antioxidant enzymes and on physiological mechanisms mitigates water deficit in sugarcane and energy cane plants
(2022-12-01) Teixeira, Gelza Carliane Marques [UNESP]; de Prado, Renato Mello [UNESP]; Rocha, Antonio Márcio Souza [UNESP]; de Oliveira Filho, Antonio Santana Batista [UNESP]; da Sousa Junior, Gilmar Silveira [UNESP]; Gratão, Priscila Lupino [UNESP]; Universidade Estadual Paulista (UNESP)
Production of sugarcane and more recently of energy cane strengthen renewable bioenergy production capacity. However, droughts resulting from climate change have limited the production of these crops. One of the strategies to attenuate water deficit damage in these crops is the use of silicate, which contributes to plant physiology. This strategy is likely to increase water use efficiency, thus promoting crop sustainability. Notwithstanding, studies on this issue are still incipient. This study assesses whether Si applied via fertigation and foliar spraying in the seedling production phase and as a complement after seedling transplanting to the soil is efficient in attenuating water deficit in sugarcane and energy cane. The study further elucidates physiological and biochemical mechanisms involved in this process. For this, the authors conducted two experiments: one with sugarcane and the other with energy cane. Treatments were arranged in randomized blocks with 5 replications, in a 2 × 2 factorial scheme. Factors consisted of the absence (-Si) and presence of Si (+ Si) applied via fertigation and foliar spraying; and two water regimes: 70% (without water deficit) and 30% (severe water deficit) of the soil water retention capacity. Silicon was supplied during the formation phase of presprouted seedlings and during the transplanting of seedlings to pots filled with samples of Entisol (Quartzipsamment). In these pots, water regimes were induced from 7 to 160 days after transplanting. Severe water deficit reduced the water content and water potential of plants. This situation induced oxidative stress and impaired gas exchange and photosynthetic water use efficiency, reducing plant growth. Silicon supply via fertigation in association with foliar spraying in the seedling formation phase with complementation after transplanting was efficient in increasing Si accumulation in the plants. Silicon was effective in attenuating severe water deficit damage up to initial culm formation through mechanisms that maintain water and physiological balance by favoring the antioxidant defense system in sugarcane and energy cane plants.
Photomorphogenic tomato mutants high-pigment 1 and aurea responses to iron deficiency
(2023-01-03) Gavassi, Marina Alves [UNESP]; Alves, Frederico Rocha Rodrigues; Monteiro, Carolina Cristina [UNESP]; Gaion, Lucas Aparecido; Alves, Letícia Rodrigues [UNESP]; Prado, Renato de Mello [UNESP]; Gratão, Priscila Lupino [UNESP]; Carvalho, Rogério Falleiros [UNESP]; Universidade Estadual Paulista (UNESP); Universidade Federal de Goiás (UFG); Universidade de Marília
Iron (Fe) is a micronutrient for plant development, as constituent of several photosynthesis- and respiration-related proteins and enzymes. Consequently, Fe deficiency leads to chlorosis in leaves and plant growth impairment. It has become increasingly evident that light signals coordinate iron homeostasis in plants. To further address new insights into how light is a fundamental part of Fe deficiency responses, we employed Micro-Tom (wild type, WT) tomato (Solanum lycopersicum L.) plants and high-pigment 1 (hp1) and aurea (au) photomorphogenic mutants, which exhibit an excessive light response and low light perception, respectively. Plant growth, pigment contents, oxidative status, and nutrient profile were analyzed. The results revealed the influence of the different genotypes on Fe deficiency responses. WT and au exhibited plant growth reduction under Fe deficiency. WT, hp1 and au demonstrated that Fe availability and light perception play fundamental roles in chlorophyll and anthocyanin biosynthesis. Lipid peroxidation was not increased for any genotype under Fe deficiency, indicating that mutations in light perception and signaling differentially modulate H2O2 production and scavenging under this condition. Additionally, macronutrients and micronutrients were taken up and distributed differently among the different plant genotypes, tissues and Fe conditions analyzed. In general, the au plants accumulated lower amounts of nutrients (Ca, S, P, Mg, B and Zn) than the WT and hp1 genotypes regardless of the Fe concentrations. Our data clearly indicates that light perception and signaling influence Fe-dependent morphophysiological responses in plants, suggesting possibilities for biotechnological improvement of crops grown under Fe shortage.
CIPC and LED lights are not effective in controlling sprout growth and development in potato with advanced physiological age
(2023-04-01) Pedrosa, V. M.D. [UNESP]; da Silva, M. B. [UNESP]; de Oliveira, R. [UNESP]; Carvalho, R. F. [UNESP]; Cecıĺio Filho, A. B. [UNESP]; Teixeira, G. H.A. [UNESP]; Universidade Estadual Paulista (UNESP); Kimberly Research and Extension Center
In seed potatoes, low irradiance blue LED light (400-500 nm) has been reported to inhibit sprout growth. Recently, similar effect of low irradiance red (660 nm) and high irradiance far-red LED (735 nm) lights have been reported. However, there is no information regarding the inhibitory effect of LED lights on sprout development in table potato tubers. Therefore, the objective of this study was to evaluate the efficacy of blue, red, and far-red LED lights on sprout development and growth on potatoes with advanced physiological age. Potato tubers of ‘Asterix’ cultivar were harvested at advanced physiological age and cured at 15°C, 95% RH for 15 days. After that, the tubers were submitted to the following treatments: dark (negative control), 20 mg L-1, CIPC (positive control), blue LED light (0.1 µmol m-2 s-1), red LED light (1.0 µmol m-2 s-1), and far-red LED light (1.0 µmol m-2 s-1). The storage was carried out in a cold room at 15°C, 95% RH for up to 30 days. Neither CIPC nor LED light treatments inhibit the sprout development and the number of sprouts (≥2 mm) increased during storage. On the other hand, the LED lights controlled the growth of sprouts, with red and far-red lights being more effective. The color parameter a* was not affected by the treatments, but the b* value reduced on tubers treated with blue and far-red LED lights, probably due to greening. Concluding, CIPC as well as LED lights did not control the development of sprouts in table potatoes at advanced physiological age; however, red and far-red LED lights did control sprout growth similar to seed potatoes.
The ultrastructure of spermatozoa of two species of Aegla (A. parana and A. quilombola) (Crustacea, Decapoda) endemic to Brazil
(2023-05-01) Wolf, Milena R. [UNESP]; Tudge, Christopher C.; Bueno, Sérgio L.S.; Zara, Fernando J. [UNESP]; Castilho, Antonio L. [UNESP]; Universidade Estadual Paulista (UNESP); American University; Smithsonian Institution; Universidade de São Paulo (USP)
The previously published ultrastructure of Aegla spermatozoa contributed to the phylogenetics of this unique taxon. The present study describes the spermatozoa of two additional aeglids, Aegla parana and A. quilombola. The spermatozoa consist of two hemispheres of the approximate same size and a bilayered acrosomal vesicle; both characteristics of the genus Aegla. The similarity of spermatozoa ultrastructure observed between A. parana and A. quilombola and the endemic Australian anomuran, Lomis hirta (Lomidae) reflects a sister group relationship, even though both are from different regions of the world and different environments today. Aeglid spermatozoa share the same organization with Lomis including the two equal size hemispheres separated by a membrane also two layers in the acrosomal vesicle with the external layer being surrounded by another membrane. The number of spermatozoa microtubular arms is unclear in Aegla, however, they are present in both the nucleus and cytoplasm. This observation does not agree with the presence of spermatozoa arms only in the nucleus, as an exclusive character for Aegla, as proposed previously. The presence of lipid-droplets and peroxisomes was observed only in the spermatozoa of A. quilombola. The greatly reduced number of spermatozoa observed in all specimens analyzed raises concerns about the conservation of several threatened species. In addition, the absence of any spermatophores seems to be a characteristic of the Aeglidae to date.
How does water deficit induce changes in primary and secondary metabolism in Corymbia citriodora seedlings?
(2023-01-01) de Medeiros, Robson Luis Silva [UNESP]; Borjas-Ventura, Ricardo Roberto; de Souza, João Vitor Oliveira [UNESP]; Fernandes, João Pedro Peixoto [UNESP]; Gratão, Priscila Lupino [UNESP]; de Paula, Rinaldo Cesar [UNESP]; Universidade Estadual Paulista (UNESP); Universidad Nacional Agraria La Molina
Corymbia citriodora is a species of commercial importance planted by small - and medium-sized producers. It produces good quality wood and has been attracting the attention of the forestry market. The occurrence of abiotic stresses will be more and more frequent, caused by climate change, which can limit plant development. Water deficit is the main factor in the reduction of eucalyptus productivity. This research aimed to evaluate the effects of water stress on the development of C. citriodora plants. The seedlings were grown in pots and submitted to five irrigation regimes (20, 35, 50, 65, and 80% of the maximum soil water retention capacity) for 110 days in a greenhouse. Plant growth, gas exchange, leaf water potential, chlorophyll, carotenoid, proline, and lipid peroxidation by malondialdehyde (MDA) content were evaluated at the end of this period. The decrease in water availability may have provided a reduction in cell number, increasing the concentration of pigments, proline, and MDA, and a reduction in leaf water potential, gas exchange, and plant growth. C. citriodora seedlings showed a significant reduction in growth when grown at levels below 50% of the maximum soil water retention capacity.
Contribution to Celastraceae palynology from Cerrado forest fragments: a focus on shape, amb and exine ornamentation
(2023-01-01) Torrati-Guioti, Paloma Gaspar; Bellonzi, Talita Kely; Gasparino, Eduardo Custódio [UNESP]; Universidade de São Paulo (USP); Universidade Estadual Paulista (UNESP)
Forest fragments in the Cerrado are areas of prominent biological importance due to their great species richness and biodiversity. These areas host endemic species of Celastraceae, the knowledge of which contributes to the preservation of this biome. This study aims to characterize the pollen morphology of 10 native species of Celastraceae found in forest fragments in the state of São Paulo, Brazil, contributing to the knowledge of the taxa for future taxonomic studies, and providing data for the conservation of the species in the forest areas. The pollen grains were acetolyzed, measured, described qualitatively and illustrated using light microscopy and scanning electron microscopy. The pollen characters referring to the pollen unit, polarity, type and number of apertures are similar in all the species studied. The shape, amb and exine ornamentation of pollen grains are the diagnostic qualitative morphological data for Celastraceae in this study. Microreticulate pollen grains were observed in Celastrus, Hippocratea and Pristimera; reticulate pollen grains with a very thick exine characterize the analyzed species of Plenckia; and reticulate and microreticulate ornamentation was observed among the species of Monteverdia. The results obtained here allow us to distinguish species of the analyzed genera and confirm the pollen diversity previously reported for Celastraceae.
Leaf size and thickness are related to frost damage in ground layer species of Neotropical savannas
(2023-02-01) de Antonio, Ariadne Cristina [UNESP]; Scalon, Marina Corrêa; Rossatto, Davi Rodrigo [UNESP]; Universidade Estadual Paulista (UNESP); Universidade Federal do Paraná (UFPR)
Savannas in southeastern Brazil are frequently exposed to frost events, causing the death of leaves and branches in many woody and herbaceous species. Frost events are frequent in these regions, with one relatively stronger than usual event every 5 years. Our experimental site at São Paulo State, Southeastern Brazil, was affected by strong frost events during June–July 2021, when temperatures reached -4 °C, causing aboveground dieback in most ground layer species, although we observed some species were not affected and maintained a fully green canopy. We used this opportunistic frost event to study and report these damages and measured leaf traits that could explain our observations, as well as point directions to ecological understanding of frost on savanna vegetation. We measured morphological leaf traits such as leaf shape (width, length, width to length ratio), leaf area, specific leaf area and leaf thickness, and we also quantified canopy and leaf damage in 17 species (5 non-affected by frost and 12 that were visually affected). We found that species with larger and thicker leaves were more prone to leaf and canopy damage (70–100% of damage) than those with smaller and thinner leaves (0% damage). These results suggest that leaf morphology may provide resistance against frost and could ultimately act as a filter favoring species that can support extreme frost events, if those became more frequent and stronger under future climatic changes.
Effect of the application of vermicompost and millicompost humic acids about the soybean microbiome under water restriction conditions
(2022-11-04) da Silva, Maura Santos Reis de Andrade [UNESP]; de Carvalho, Lucas Amoroso Lopes [UNESP]; Braos, Lucas Boscov [UNESP]; de Sousa Antunes, Luiz Fernando; da Silva, Camilla Santos Reis de Andrade; da Silva, Cleudison Gabriel Nascimento; Pinheiro, Daniel Guariz [UNESP]; Correia, Maria Elizabeth Fernandes; Araújo, Ednaldo da Silva; Colnago, Luiz Alberto; Desoignies, Nicolas; Zonta, Everaldo; Rigobelo, Everlon Cid [UNESP]; Universidade Estadual Paulista (UNESP); Universidade Federal Rural do Rio de Janeiro (UFRRJ); Universidade Federal de Lavras (UFLA); Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA); Centre D’Etudes et Recherche Appliquée-Haute Ecole Provinciale du Hainaut Condorcet
Humic substances (HSs) are constituent fractions of organic matter and are highly complex and biologically active. These substances include humic acids (HA), fulvic acids (FA), and humin. HS are known to stimulate the root system and plant growth and to mitigate stress damage, including hydric stress. Humic acids have already been reported to increase microbial growth, affecting their beneficial effect on plants. However, there is scarce information on whether HA from vermicompost and millicompost, along with Bradyrhizobium, improves the tolerance of soybean to water restriction. This study aimed to evaluate the responses of soybean plants to the application of vermicompost HA (HA-V) and millicompost (HA-M) along with Bradyrhizobium sp. under water restriction. The experiment was carried out in a greenhouse, and the treatments received Bradyrhizobium sp. inoculation with or without the application of HA from vermicompost and millicompost with or without water restriction. The results showed that HA provided greater soybean growth and nodulation than the control. The application of HA-M stimulated an increase in the richness of bacterial species in roots compared to the other treatments. After the application of water stress, the difference between the treatments disappeared. Microbial taxa were differentially abundant in plants, with the fungal fraction most affected by HA application in stressed roots. HA-V appears to be more prominent in inducing taxa under stress conditions. Although the results showed slight differences between HA from vermicompost and millicompost regarding plant growth, both humic acids promoted an increase in plant development compared to the control.
Diversity and distribution of Lentibulariaceae in Bahia state, Brazil: implications for phytogeography and conservation
(2022-08-08) Guedes, Felipe Martins; Oliveira Miranda, Vitor Fernandes [UNESP]; Alves, Marccus; Universidade Federal de Pernambuco (UFPE); Universidade Estadual Paulista (UNESP)
Bahia state harbours an immense diversity of plant species with several cases of endemism, especially in the savanna wetlands, typical ecosystems where most Lentibulariaceae representatives occur. In this context, we aimed to improve the characterization of these savanna wetlands in terms of species richness of Lentibulariaceae, their phytogeographic patterns, endemism, forms of rarity, threats to their habitats, and conservation efforts. Herein we present the synopsis of the 42 species of Lentibulariaceae that occur in Bahia state, providing short diagnostic characterization, photographs of living specimens, updated geographic distribution displayed in maps, new records, and discussion concerning phytogeographic patterns, endemism, rarity, habitat characterization and current scenario of threats and conservation. Our results show a disjunct distribution and similarity in Lentibulariaceae species composition between savanna wetlands, corroborating previous hypotheses of vegetation connections during moister climatic conditions in the past. Moreover, differences in species composition among different restinga areas are consistent with biogeographical and paleomodelling studies pointing the São Francisco River as a geographic barrier influencing speciation and genetic diversity. Finally, we emphasize the situation of abandonment in some Protected Areas, lacking proper infrastructure, managers, management plans and board, and insufficient results for the effective conservation and protection of the environment and species.
Stem and pseudostem growth play a key role in biomass accumulation of guineagrass in long regrowth cycles
(2022-01-01) Brunetti, Henrique Bauab; Oliveira, Ricardo Ferraz De; Pezzopane, José Ricardo Macedo; Pedreira, Bruno Carneiro; Carvalho, Rogério Falleiros [UNESP]; Pedreira, Carlos Guilherme Silveira; Santos, Patrícia Menezes; Universidade de São Paulo (USP); Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA); Southeast Research and Extension Center; Universidade Estadual Paulista (UNESP)
Context: Tall bunch-type tropical forage grasses are known for their rapid (true) stem elongation late in the regrowth cycle, even during the vegetative phase. Aims: This study aimed to evaluate the stem and pseudostem growth pattern of 'Mombaça' guineagrass [Megathyrsus maximus (Jacq.) BK Simon & SWL Jacobs] grown in field conditions and how this relates to its high biomass accumulation during long regrowth cycles. Methods: A guineagrass field was managed from December 2017 to January 2019, in three regrowth cycles of 10, 14 and 12 weeks duration. Individual tillers were assessed weekly to measure stem, pseudostem and leaf elongation, leaf appearance; and angle of insertion of the leaves. Aboveground biomass samples were taken weekly for biomass accumulation and leaf area index assessment. Key results: At the beginning of each regrowth cycle, the pseudostem elongated while the stem length remained constant. Subsequently, the pseudostem length reached a plateau, while the stem length increased at a constant rate. Because of a positive relationship between pseudostem and leaf laminae lengths, the long pseudostem ensured the formation of long leaves in tall tillers and positive net leaf elongation in long regrowth cycles. Conclusions: The high biomass accumulation reflected the continuous positive net leaf elongation by the tillers and was underpinned by the younger leaves being more erect than the older ones, allowing for lower self-shading of the older leaves and greater leaf tissue retention. Implications: The high production of tropical forage grasses in late regrowth should be utilised with caution, as it is underpinned by stem elongation and meristem elevation.
Efficacy and safety of morphine and methadone as analgesics in a balanced anaesthetic protocol in rabbits
(2022-01-01) Nobre, Camila Vieira; Uscategui, Ricardo A.R.; Noriega, Jorge; Gasser, Beatriz [UNESP]; Pazzini, Josiane Morais; de Almeida, Vívian Tavares [UNESP]; de Nardi, Andrigo Barboza [UNESP]; de Andrade, James Newton; Universidade Federal de Viçosa (UFV); Universidad CES; Corregimiento San José del Nus; Universidade Estadual Paulista (UNESP); União das Faculdades dos Grandes Lagos
The efficacy of preventive analgesia and the cardiopulmonary effects of morphine or methadone in rabbits undergoing experimental skin surgery were evaluated and compared. Thirty-six rabbits were randomly assigned to three experimental groups: Control, Morphine, and Methadone. The rabbits received midazolam 1 mg/kg IM associated with: placebo (NaCl 0.9%) 0.05 ml/kg, methadone 0.5 mg/kg or morphine 0.5 mg/kg, depending on the experimental group. Anaesthesia was induced and maintained with isoflurane. Heart (HR) and respiratory (fR) rates, peripheral oxygen saturation (SpO2), mean arterial pressure (MAP), and body temperature were assessed every 10 minutes. Electrocardiographic examination was performed after sedation, in the trans and immediate postoperative period. After procedure, the control group received tramadol 5 mg/kg IV. Postoperative analgesia was assessed using the visual analogue scale (VAS) and Von-Frey filament stimulation responses. All variables were compared between groups by ANOVA or Friedman. Methadone and morphine caused an increase in MAP (p=0.0112) and a decrease in HR (p=0.0001). fR and SpO2 were reduced in the methadone group (p=0.0100). The response to Von-Frey filaments (p=0.6824) and VAS (p=0.7661) were similar between treatments, however, the control group presented a higher proportion of analgesic rescue (33%) compared to morphine (19%) and methadone (12%). Electrocardiographic variables were similar between treatments (p>0.05). In conclusion, preventive treatment with morphine or methadone was effective in controlling trans and postoperative pain in rabbits, and its cardiovascular effects were limited; however, methadone caused marked respiratory depression.
Metaprofiling of the Bacterial Community in Colonized Compost Extracts by Agaricus subrufescens
(2022-10-01) Iossi, Matheus Rodrigo [UNESP]; Palú, Isabela Arruda [UNESP]; Soares, Douglas Moraes; Vieira, Wagner G. [UNESP]; Alves, Lucas Silva [UNESP]; Stevani, Cassius V.; Caitano, Cinthia E. C. [UNESP]; Atum, Samir V. F.; Freire, Renato S.; Dias, Eustáquio S.; Zied, Diego Cunha [UNESP]; Universidade Estadual Paulista (UNESP); Universidade de São Paulo (USP); Universidade Federal de Lavras (UFLA)
It is well-known that bacteria and fungi play important roles in the relationships between mycelium growth and the formation of fruiting bodies. The sun mushroom, Agaricus subrufescens, was discovered in Brazil ca. 1960 and it has become known worldwide due to its medicinal and nutritional properties. This work evaluated the bacterial community present in mushroom-colonized compost extract (MCCE) prepared from cultivation of A. subrufescens, its dynamics with two different soaking times and the influence of the application of those extracts on the casing layer of a new compost block for A. subrufescens cultivation. MCCEs were prepared through initial submersion of the colonized compost for 1 h or 24 h in water followed by application on casing under semi-controlled conditions. Full-length 16S rRNA genes of 1 h and 24 h soaked MCCE were amplified and sequenced using nanopore technology. Proteobacteria, followed by Firmicutes and Planctomycetes, were found to be the most abundant phyla in both the 1 h and 24 h soaked MCCE. A total of 275 different bacterial species were classified from 1 h soaked MCCE samples and 166 species from 24 h soaked MCCE, indicating a decrease in the bacterial diversity with longer soaking time during the preparation of MCCE. The application of 24 h soaked MCCE provided increases of 25% in biological efficiency, 16% in precociousness, 53% in the number of mushrooms and 40% in mushroom weight compared to control. Further investigation is required to determine strategies to enhance the yield and quality of the agronomic traits in commercial mushroom cultivation.
Iron biofortification in quinoa: Effect of iron application methods on nutritional quality, anti-nutrient composition, and grain productivity
(2023-03-15) Lata-Tenesaca, Luis Felipe [UNESP]; de Mello Prado, Renato [UNESP]; Ajila-Celi, Gabriela Eugenia [UNESP]; da Silva, Dalila Lopes; Junior, José Sidnaldo Pinzetta [UNESP]; Mattiuz, Ben-Hur [UNESP]; Universidade Federal de Viçosa (UFV); Universidade Estadual Paulista (UNESP); Universidade de São Paulo (USP)
Biofortification of iron (Fe) in quinoa (Chenopodium quinoa) grains should have benefits for human health and food security. However, effects of this approach on productivity, as well as Fe content and grain quality remain unknown. Thus, a greenhouse experiment was conducted to determine the impacts of different methods of Fe delivery in a hydroponic system, root application (90 µmol/L), foliar spraying (9 mmol/L), combined root and foliar application, and control (no Fe). Foliar Fe application in four applications at vegetative and reproductive stages stood out from root application in promoting quinoa growth and productivity, perhaps because of greater accumulation of Fe in the plants, leading to increased photosynthetic pigments and electron transport. Foliar application of Fe also improved grain quality, as it was associated with higher Fe contents, ascorbic acid (AsA), total proteins, and manganese (Mn). In addition, there was a decrease in antinutritional compounds and phosphorus (P) in grains. Foliar Fe application can be an efficient agronomic practice to obtain Fe-biofortified quinoa grains and was associated with improved physiological responses and productivity.
Beneficial Role of Silicon on Regulating C, N, and P Stoichiometric Homeostasis and the Growth of Sugarcane Seedlings under Aluminum Toxicity
(2022-12-01) da Silveira Sousa Junior, Gilmar [UNESP]; Hurtado, Alexander Calero [UNESP]; de Souza Junior, Jonas Pereira [UNESP]; de Mello Prado, Renato [UNESP]; de Cássia Piccolo, Marisa; Dos Santos, Durvalina Maria Mathias [UNESP]; Universidade Estadual Paulista (UNESP); Universidade de São Paulo (USP); University of Sancti Spiritus “Jose Marti Perez” (UNISS)
This study investigates the protective role of silicon (Si) on growth performance, nutrient homeostasis, and C:N:P stoichiometric of sugarcane (Saccharum spp.) seedlings under aluminum (Al) stress in hydroponic conditions. Experiments were conducted as a factorial scheme (2 × 2) in a randomized complete block design (RCBD), with four replications, for each sugarcane cultivar (“CTC9002” and “CTC9003”). They were grown in pots filled with normal Clark nutrient (pH = 5.8 without Al) and acidic Clark nutrient solution (pH = 4.5 with 15 mg L−1 of Al, as aluminum sulfate [Al2 (SO4)3·18H2O]) in the absence or presence of Si (2 mM, as potassium silicate (K2SiO3). Sugarcane seedlings of both cultivars grown under Al stress alone significantly decreased root, culm, and leaf dry biomass, and this adverse effect was reversed by Si supplementation. Added Si also modified nutrient homeostasis of both sugarcane cultivars, and these effects varied depending on plant organs. Si decreased the concentration of C, N, and P and correspondingly increased C:N, C:P, and N:P stoichiometric. In addition, both sugarcane cultivars had a positive response to Si supplementation, but cultivar “CTC9003” is more recommended under added Si to ameliorate the detrimental effects caused by Al toxicity. The findings of this study indicate that Si promoted attenuation of Al-stressed sugarcane seedlings by regulating nutrient and homeostasis stoichiometric, leading to improve dry biomass production.

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