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1.
J Agric Food Chem ; 67(38): 10577-10586, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31490682

RESUMO

Root and rhizosphere is important for phosphorus (P) uptake in rice plants. However, little is known about the detailed regulation of irrigation regimes, especially frequently alternate wetting and drying (FAWD), on P usage of rice plants. Here, we found that compared with normal water and P dose, FAWD with a reduced P dose maintained the grain yield in two rice varieties. Compared to rice variety Gaoshan1, rice variety WufengyouT025 displayed a higher grain yield, shoot P content, rhizosphere acid phosphatase activity, abundance of bacteria, and bacterial acid phosphatase gene of rhizosphere. Moreover, the FAWD regime may increase the abundance of bacteria with acid phosphatase activity to release available phosphorus in the rhizosphere, which is associated with rice varieties. Our results suggest that an optimized management of irrigation and phosphorous application can enhance both water and phosphorus use efficiency without sacrificing the yield, which may contribute significantly to sustainable agriculture production.


Assuntos
Irrigação Agrícola/métodos , Produção Agrícola/métodos , Oryza/crescimento & desenvolvimento , Fósforo/metabolismo , Microbiologia do Solo , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Produção Agrícola/instrumentação , Fertilizantes/análise , Microbiota , Oryza/classificação , Oryza/metabolismo , Oryza/microbiologia , Rizosfera , Água/metabolismo
2.
BMC Plant Biol ; 19(1): 345, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31390991

RESUMO

BACKGROUND: Aquaporin (AQP) proteins comprise a group of membrane intrinsic proteins (MIPs) that are responsible for transporting water and other small molecules, which is crucial for plant survival under stress conditions including salt stress. Despite the vital role of AQPs, little is known about them in cucumber (Cucumis sativus L.). RESULTS: In this study, we identified 39 aquaporin-encoding genes in cucumber that were separated by phylogenetic analysis into five sub-families (PIP, TIP, NIP, SIP, and XIP). Their substrate specificity was then assessed based on key amino acid residues such as the aromatic/Arginine (ar/R) selectivity filter, Froger's positions, and specificity-determining positions. The putative cis-regulatory motifs available in the promoter region of each AQP gene were analyzed and results revealed that their promoter regions contain many abiotic related cis-regulatory elements. Furthermore, analysis of previously released RNA-seq data revealed tissue- and treatment-specific expression patterns of cucumber AQP genes (CsAQPs). Three aquaporins (CsTIP1;1, CsPIP2;4, and CsPIP1;2) were the most transcript abundance genes, with CsTIP1;1 showing the highest expression levels among all aquaporins. Subcellular localization analysis in Nicotiana benthamiana epidermal cells revealed the diverse and broad array of sub-cellular localizations of CsAQPs. We then performed RNA-seq to identify the expression pattern of CsAQPs under salt stress and found a general decreased expression level of root CsAQPs. Moreover, qRT-PCR revealed rapid changes in the expression levels of CsAQPs in response to diverse abiotic stresses including salt, polyethylene glycol (PEG)-6000, heat, and chilling stresses. Additionally, transient expression of AQPs in N. benthamiana increased leaf water loss rate, suggesting their potential roles in the regulation of plant water status under stress conditions. CONCLUSIONS: Our results indicated that CsAQPs play important roles in response to salt stress. The genome-wide identification and primary function characterization of cucumber aquaporins provides insight to elucidate the complexity of the AQP gene family and their biological functions in cucumber.


Assuntos
Aquaporinas/fisiologia , Cucumis sativus/genética , Proteínas de Plantas/fisiologia , Aquaporinas/genética , Aquaporinas/metabolismo , Cucumis sativus/metabolismo , Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Peróxido de Hidrogênio/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética , Transcriptoma , Água/metabolismo
3.
J Agric Food Chem ; 67(35): 9697-9704, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31403787

RESUMO

In higher plants, seed size is an important parameter and agricultural trait in many aspects of evolutionary fitness. The loss of water-deficiency-induced crop yield is the largest among all natural hazards. Under water-deficient stress, the most prevalent response to terminal stress is to accelerate the early arrest of floral development and, thereby, to accelerate fruit/seed production, which consequently reduces seed size. This phenomenon is well-known, but its molecular mechanism is not well-reviewed and characterized. However, increasing evidence have indicated that water-deficient stress is always coordinated with three genetic signals (i.e., seed size regulators, initial seed size, and fruit number) that decide the final seed size. Here, our review presents new insights into the mechanism underlying cross-talk water-deficient stress signaling with three genetic signals controlling final seed size. These new insights may aid in preliminary screening, identifying novel genetic factors and future design strategies, or breeding to increase crop yield.


Assuntos
Sementes/citologia , Água/metabolismo , Secas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Estresse Fisiológico , Água/análise
4.
BMC Plant Biol ; 19(1): 297, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31286880

RESUMO

BACKGROUND: The modification effect of leaching fraction (LF) on the physiological responses of plants to irrigation water salinity (ECiw) remains unknown. Here, leaf gas exchange, photosynthetic light-response and CO2-response curves, and total carbon (C) and nitrogen (N) accumulation in hot pepper leaves were investigated under three ECiw levels (0.9, 4.7 and 7.0 dS m- 1) and two LFs treatments (0.17 and 0.29). RESULTS: Leaf stomatal conductance was more sensitive to ECiw than the net photosynthesis rate, leading to higher intrinsic water use efficiency (WUE) in higher ECiw, whereas the LF did not affect the intrinsic WUE. Carbon isotope discrimination was inhibited by ECiw, but was not affected by LF. ECiw reduced the carboxylation efficiency, photosynthetic capacity, photorespiration rate, apparent quantum yield of CO2 and irradiance-saturated rate of gross photosynthesis; however, LF did not influence any of these responses. Total C and N accumulation in plants leaves was markedly increased with either decreasing ECiw or increasing LF. CONCLUSIONS: The present study shows that higher ECiw depressed leaf gas exchange, photosynthesis capacity and total C and N accumulation in leaves, but enhanced intrinsic WUE. Somewhat surprisingly, higher LF did not affect the intrinsic WUE but enhanced the total C and N accumulation in leaves.


Assuntos
Irrigação Agrícola , Capsicum/fisiologia , Fotossíntese , Salinidade , Água/metabolismo , Carbono/metabolismo , Nitrogênio/metabolismo , Água/análise
5.
Sci Total Environ ; 690: 956-964, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31302559

RESUMO

In present study, a potential bacterial isolate Acetobacter pasteurianus SKYAA25 was found to be very effective in the bioconversion of apple pomace to acetic acid. The isolated strain was tolerant to high ethanol concentrations of upto 14% and temperature of 42 °C. Fermentation of apple pomace alone in presence of brewing yeast produced 7.3% of bio-ethanol which was further used for acetic acid production. Apple pomace in combination with cane molasses produced 14% of bio-ethanol. The fermented bio-ethanol was used as medium for acetic acid production which yielded 52.4 g of acetic acid/100 g of DM (Dry Matter) of apple pomace. Hence, an ecofriendly process has been developed that is entirely based on microbial processing of apple pomace to produce acetic acid without involving commercial enzymes. The present bio-conversion will prove to be beneficial for utilizing food and beverage industrial waste in the production of acetic acid.


Assuntos
Ácido Acético/metabolismo , Acetobacter/fisiologia , Adaptação Fisiológica/fisiologia , Etanol/metabolismo , Fermentação , Malus/microbiologia , Saccharomyces cerevisiae , Água/metabolismo
6.
J Sci Food Agric ; 99(13): 6049-6059, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31342530

RESUMO

BACKGROUND: The scarcity of irrigation water is severely affecting global crop production. In this context, biostimulants are increasingly used as alternatives means against abiotic stress conditions. In this study, phenolic compounds composition and bioactive properties of common bean (Phaseolus vulgaris L.) plants grown under water stress conditions and biostimulants application were investigated. RESULTS: Sixteen individual phenolic compounds were detected in both pods and seeds with a notable difference in their compositional profile. A significant effect on phenolic compounds content and composition was also observed for the biostimulants tested. Regarding the antibacterial activity, pods of the second harvest and seed extracts showed significant efficacy against Bacillus cereus, especially in water-stressed plants, where all biostimulant treatments were more effective than positive controls. Moreover, all biostimulant treatments for seed extracts of water-stressed plants were more effective against Staphylococcus aureus compared with ampicillin, whereas streptomycin showed the best results. Extracts from pods of the second harvest from normally irrigated plants showed the best results against the fungi tested, except for Penicillium verrucosum var. cyclopium. Finally, no significant cytotoxic effects were detected. CONCLUSION: In conclusion, the biostimulants tested increased total phenolic compounds content compared with control treatment, especially in pods of the first harvest and seeds of water-stressed plants. Moreover, bioactive properties showed a varied response in regard to irrigation and biostimulant treatment. Therefore, biostimulants can be considered as a useful means towards increasing phenolic compounds content, and they may also affect the antimicrobial properties of pods and seeds extracts. © 2019 Society of Chemical Industry.


Assuntos
Desidratação , Phaseolus/química , Phaseolus/fisiologia , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Água/metabolismo , Bacillus cereus/efeitos dos fármacos , Bacillus cereus/crescimento & desenvolvimento , Phaseolus/crescimento & desenvolvimento , Phaseolus/microbiologia , Fenóis/química , Fenóis/metabolismo , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Sementes/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Estresse Fisiológico , Água/análise
7.
J Agric Food Chem ; 67(25): 7098-7109, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31199133

RESUMO

Wine aging bouquet is defined as a positive, complex evolution of aromas during bottle aging. The aim of this study was to look for the link between some of the vine status parameters and the development, during wine aging, of volatile compounds such as DMS, tabanones, and some wine aromatic heterocycles. The potential influence of air temperature was investigated as well as vine nitrogen and water status. Wines were obtained by microvinification from plots of Vitis vinifera L. cv. Merlot, Cabernet-Sauvignon, and Cabernet franc, over vintages from 1996 to 2007, and cellar-aged until 2014. Wine aging aromas were quantified using gas chromotography-mass spectrometry. The effects of the vintage and vine water and nitrogen status were greater than the varietal effects. The nine aroma compounds measured showed very high levels in the 2003 vintage. The results revealed a positive link between vine nitrogen status and dimethyl-sulfide and N, S, O-heterocycle levels measured in the aged wines. Levels of 4-[2-butylidene]-3,5,5-trimethyl-2-cyclohexen-1-one and 4-[( 3E)-1-butylidene]-3,5,5-trimethyl-2-cyclohexen-1-one (megastigmatrienones; tabanone) isomers increased when the vines were affected by a water deficit.


Assuntos
Aromatizantes/química , Nitrogênio/análise , Vitis/química , Compostos Orgânicos Voláteis/química , Água/análise , Vinho/análise , Irrigação Agrícola , Manipulação de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Isomerismo , Nitrogênio/metabolismo , Temperatura Ambiente , Fatores de Tempo , Vitis/metabolismo , Água/metabolismo
8.
J Agric Food Chem ; 67(25): 7050-7059, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31240932

RESUMO

This work aimed to investigate the effect of selenium (Se) and irrigation on the grain yield, on the forms of Se, phenols, and carotenes, and on some antioxidant activities of maize ( Zea mays L.) grains. To reach this goal, a 2 year experiment was undertaken. Maize was fertigated with sodium selenite at the rate of 200 g of Se ha-1 and grown under two water regimes. While the irrigation did not show a clear effect on the selected parameters, Se fertigation increased the contents of inorganic and organic Se forms, xanthophyll, and salicylic acid. Furthermore, while Se fertigation decreased the hydroxycinnamic acid content, generally higher antioxidant activities were found in Se-treated grains than in the control. These findings suggest that Se fertigation increases most of the nutraceutical values of maize grains, which therefore might improve human and livestock health and could increase the maize grain shelf life and its byproducts.


Assuntos
Antioxidantes/análise , Biofortificação/métodos , Suplementos Nutricionais/análise , Selenito de Sódio/metabolismo , Água/análise , Zea mays/química , Irrigação Agrícola , Antioxidantes/metabolismo , Alimentos Fortificados/análise , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Selenito de Sódio/análise , Solo/química , Água/metabolismo , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo
9.
Food Chem ; 295: 300-310, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174762

RESUMO

While fleshy fruit softening has long been mechanistically linked to cell wall disassembly, the importance of the fruit cuticle in water relations and firmness has been suggested through studies of the long-shelf life delayed fruit deterioration (dfd) tomato genotype. We tested the hypothesis that dynamic cuticle properties and composition affect tomato fruit transpiration and firmness and are influenced by environmental water availability, using dfd and two normally softening fruit cultivars, Ailsa Craig (AC) and M82, grown under control and water stress (WS) conditions. The effect of WS was also assessed following fruit detachment. WS increased fruit firmness, cuticle load, and the expression of cuticle biosynthetic genes, while reducing cuticle permeability and fruit transpiration rate in AC and M82, but not in dfd fruit. This study supports a direct relationship between fruit cuticle properties, transpiration and firmness, and provides insights into the adaptation of tomato genotypes to environments where water can be scarce.


Assuntos
Desidratação , Frutas/fisiologia , Lycopersicon esculentum/fisiologia , Armazenamento de Alimentos , Frutas/química , Frutas/metabolismo , Genótipo , Lycopersicon esculentum/química , Lycopersicon esculentum/metabolismo , Transpiração Vegetal , Água/metabolismo
10.
J Chem Theory Comput ; 15(8): 4318-4331, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31241940

RESUMO

The relative prevalence of native protein-protein interactions (PPIs) are the cornerstone for understanding the structure, dynamics and mechanisms of function of protein complexes. In this study, we develop a scheme for scaling the protein-water interaction in the CHARMM36 force field, in order to better fit the solvation free energy of amino acids side-chain analogues. We find that the molecular dynamics simulation with the scaled force field, CHARMM36s, as well as a recently released version, CHARMM36m, effectively improve on the overly sticky association of proteins, such as ubiquitin. We investigate the formation of a heterodimer protein complex between the SAM domains of the EphA2 receptor and the SHIP2 enzyme by performing a combined total of 48 µs simulations with the different potential functions. While the native SAM heterodimer is only predicted at a low rate of 6.7% with the original CHARMM36 force field, the yield is increased to 16.7% with CHARMM36s, and to 18.3% with CHARMM36m. By analyzing the 25 native SAM complexes formed in the simulations, we find that their formation involves a preorientation guided by Coulomb interactions, consistent with an electrostatic steering mechanism. In 12 cases, the complex could directly transform to the native protein interaction surfaces with only small adjustments in domain orientation. In the other 13 cases, orientational and/or translational adjustments are needed to reach the native complex. Although the tendency for non-native complexes to dissociate has nearly doubled with the modified potential functions, a dissociation followed by a reassociation to the correct complex structure is still rare. Instead, the remaining non-native complexes undergo configurational changes/surface searching, which, however, rarely leads to native structures on a time scale of 250 ns. These observations provide a rich picture of the mechanisms of protein-protein complex formation and suggest that computational predictions of native complex PPIs could be improved further.


Assuntos
Mapas de Interação de Proteínas , Proteínas/metabolismo , Humanos , Simulação de Dinâmica Molecular , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/química , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/metabolismo , Ligação Proteica , Conformação Proteica , Multimerização Proteica , Proteínas/química , Receptor EphA2/química , Receptor EphA2/metabolismo , Eletricidade Estática , Termodinâmica , Ubiquitina/química , Ubiquitina/metabolismo , Água/metabolismo
11.
Environ Monit Assess ; 191(7): 440, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-31203473

RESUMO

Production of quality jute fibre primarily depends on the retting process of jute. However, the quality of retting water is of great concern because of the scarcity of available water bodies for retting. A study conducted on physico-chemical and microbiological changes in retting water (pre- and post-retting) from four intensively jute-growing districts namely Nadia, North 24 Parganas, Hooghly and South Dinajpur of West Bengal, India, during jute retting. The post-retting water samples recorded lower pH (6.22 to 7.08) and higher EC (electrical conductivity) (0.509 to 0.850 ds/m) compared with pre-retting water samples (pH 6.63 to 7.44; EC 0.197 to 0.330 ds/m) collected from all the four districts under study. The biological oxygen demand (BOD) and chemical oxygen demand (COD) increased several folds in the post-retting water samples indicating very high microbial growth and activities and depleted oxygen level compared with pre-retting water. The Ca + Mg (calcium + magnesium) content in pre-retting water was high (24.15 to 36.60 ppm) which raised further (61.30 to 103.67 ppm) in post-retting water, while the bicarbonate content also increased and ranged between 2.72 and 6.81 me/l in post-retting water compared with its status in pre-retting water (1.30 to 3.15 me/l). The post-retting water was found to be a rich source of nutrients like nitrogen (N), phosphorus (P), iron (Fe), manganese (Mn), zinc (Zn) and copper (Cu) which increased substantially because of jute retting as compared with their status in pre-retting water. The population of pectinolytic, xylanolytic, cellulolytic and ligninolytic bacterial cfu (colony forming unit) increased by 1.5 times in post-retting water as compared with pre-retting water, because these specific bacterial population were involved in the degradation of pectin, xylan, cellulose and lignin during retting of jute. Thus, post-retting water can be judiciously used as a potent source of primary, secondary and micronutrients for succeeding crops besides having higher BOD and COD as a result of higher microbial growth related to jute retting.


Assuntos
Bactérias/metabolismo , Corchorus/metabolismo , Lignina/metabolismo , Água/metabolismo , Bicarbonatos/análise , Cálcio/análise , Celulose , Monitoramento Ambiental , Índia , Magnésio/análise , Oxigênio/metabolismo
12.
J Plant Physiol ; 239: 1-9, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31177025

RESUMO

Elicitation is an economic and sustainable technique for increasing the content of secondary metabolites, mainly bioactive compounds, in plants grown for better human nutrition. The aim of this study was to compare the physiological responses (water relations and mineral nutrition) and the enrichment in glucosinolates (GLSs) and phenolic compounds of broccoli plants (Brassica oleracea L. var. italica) receiving different elicitation treatments. The treatments involved the priming of seeds with KCl and the exposure of plants to elicitors, including K2SO4 and NaCl solutions and foliar sprays of methyl jasmonate (MeJA), salicylic acid (SA), and methionine (Met). The physiological response of the plants in terms of root hydraulic conductance was improved by priming with KCl and elicitation with MeJA or Met. Foliar application of Met significantly increased the plant biomass and enhanced mineral nutrition. In general, all treatments increased the accumulation of indole GLSs, but K2SO4 and MeJA gave the best response and MeJA also favored the formation of a newly described compound, cinnamic-GLS, in the plants. Also, the use of Met and SA as elicitors and the supply of K2SO4 increased the abundance of phenolic compounds; K2SO4 also enhanced growth but did not alter the water relations or the accumulation of mineral nutrients. Therefore, although the response to elicitation was positive, with an increased content of bioactive compounds, regulation of the water relations and of the mineral status of the broccoli plants was critical to maintain the yield.


Assuntos
Brassica/efeitos dos fármacos , Brassica/fisiologia , Cloreto de Potássio/administração & dosagem , Cloreto de Sódio/administração & dosagem , Sulfatos/administração & dosagem , Acetatos/administração & dosagem , Ciclopentanos/administração & dosagem , Glucosinolatos/metabolismo , Metionina/administração & dosagem , Minerais/metabolismo , Nutrientes/metabolismo , Oxilipinas/administração & dosagem , Fenóis/metabolismo , Reguladores de Crescimento de Planta , Ácido Salicílico/administração & dosagem , Água/metabolismo
13.
Biochemistry (Mosc) ; 84(Suppl 1): S144-S158, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31213200

RESUMO

This short review describes recent progress in using optical clearing (OC) technique in skin studies. Optical clearing is an efficient tool for enhancing the probing depth and data quality in multiphoton microscopy and Raman spectroscopy. Here, we discuss the main mechanisms of OC, its safety, advantages, and limitations. The data on the OC effect on the skin water content are presented. It was demonstrated that 70% glycerol and 100% OmnipaqueTM 300 reduce the water content in the skin. Both OC agents (OCAs) significantly affect the strongly bound and weakly bound water. However, OmnipaqueTM 300 causes considerably less skin dehydration than glycerol. In addition, the results of examination of the OC effect on autofluorescence in two-photon excitation and background fluorescence in Raman scattering at different skin depths are presented. It is shown that OmnipaqueTM 300 is a promising OCA due to its ability to reduce background fluorescence in the upper skin layers. The possibility of multimodal imaging combining optical methods and OC technique is discussed.


Assuntos
Microscopia de Fluorescência por Excitação Multifotônica/métodos , Pele/diagnóstico por imagem , Pele/ultraestrutura , Análise Espectral Raman/métodos , Dermatologia , Glicerol/química , Humanos , Água/metabolismo
14.
Food Chem ; 295: 520-529, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174791

RESUMO

This study aimed to investigate the effect of stunning stress on textural properties and water-holding capacity (WHC) of silver carp (Hypophthalmichthys molitrix) fillets and its underlying mechanisms based on intrinsic proteases activity, myofibril microstructure, and myowater dynamic measurements. The results suggested that compared with the non-stressful percussion, ice/water and gill cut stunning resulted in accelerated muscle tenderization with intensive myofibril disintegration and sarcolemma-myofibril detachments. Myowater mobility and distribution were altered by stunning stress, in which gill cut facilitated the migration of immobilized water and free water, thus enhancing the centrifugation loss. In addition, stunning stress promoted the activation of endogenous proteases and the release of cathepsin B and L from lysosomes to myofibrils, which showed significant (P < 0.01) correlations with decreased shear force and elevated myofibril fragmentation index of fillets. Therefore, faster accumulation of cathepsins and myofibril disintegration together contributed to the weakening of texture and WHC in stunning-stressed fish fillets.


Assuntos
Alimentos Marinhos/análise , Animais , Carpas , Catepsina B/metabolismo , Catepsina L/metabolismo , Lisossomos/enzimologia , Espectroscopia de Ressonância Magnética , Miofibrilas/metabolismo , Miofibrilas/ultraestrutura , Resistência ao Cisalhamento , Estresse Fisiológico , Água/química , Água/metabolismo
15.
Nat Commun ; 10(1): 2825, 2019 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-31249299

RESUMO

The formation of stomata and leaf mesophyll airspace must be coordinated to establish an efficient and robust network that facilitates gas exchange for photosynthesis, however the mechanism by which this coordinated development occurs remains unclear. Here, we combine microCT and gas exchange analyses with measures of stomatal size and patterning in a range of wild, domesticated and transgenic lines of wheat and Arabidopsis to show that mesophyll airspace formation is linked to stomatal function in both monocots and eudicots. Our results support the hypothesis that gas flux via stomatal pores influences the degree and spatial patterning of mesophyll airspace formation, and indicate that this relationship has been selected for during the evolution of modern wheat. We propose that the coordination of stomata and mesophyll airspace pattern underpins water use efficiency in crops, providing a target for future improvement.


Assuntos
Células do Mesofilo/química , Células do Mesofilo/metabolismo , Estômatos de Plantas/química , Estômatos de Plantas/metabolismo , Arabidopsis/química , Arabidopsis/metabolismo , Gases/metabolismo , Porosidade , Triticum/química , Triticum/metabolismo , Água/metabolismo
16.
Food Chem ; 293: 472-478, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151636

RESUMO

Water activity (aw) and temperature are two pivotal environmental factors affecting Aspergillus flavus growth and aflatoxin production. Here, we found that AFB1 production on polished rice can occur over a wider range of temperature × aw levels than that on paddies. For fungal growth on polished rice, the optimum conditions were aw 0.92-0.96 and 28-37 °C. The maximum amounts of AFB1 on polished rice was observed at 33 °C and aw 0.96. Compared to 33 °C, all tested genes of A. flavus on polished rice were significantly up-regulated at 25 °C under aw 0.96. The late structural genes of pathway were significantly down-regulated at 37 °C under aw 0.96, although aflR and aflS and most of early structural genes were up-regulated. Compared to aw 0.96, most of pathway genes were significantly down-regulated at aw 0.90 and 0.99 under 33 °C, although two regulatory genes were up-regulated at aw 0.90.


Assuntos
Aflatoxinas/biossíntese , Aspergillus flavus/metabolismo , Aflatoxinas/análise , Aspergillus flavus/genética , Aspergillus flavus/crescimento & desenvolvimento , Cromatografia Líquida de Alta Pressão , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Oryza/microbiologia , Temperatura Ambiente , Água/química , Água/metabolismo
17.
Plant Physiol Biochem ; 141: 315-324, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31207492

RESUMO

Different SA concentrations (10, 100 and 1000 µM) were applied in young olive trees (Olea europaea L.) subjected to drought and rewatering. Plants treated with 10 µM exhibited a close behavior to SA-starved plants. Although both 100 and 1000 µM improved the balance between ROS production and scavenging, 100 µM was more efficient. During drought, 100 µM improved ROS detoxification and scavenging by the maintenance or overaccumulation of soluble proteins. During recovery, soluble proteins return to well-watered values and increased the investment in non-enzymatic antioxidants. 100 µM was also the most effective in plant ionome regulation, improving macro and micronutrients uptake, namely P, Fe, Mn and Zn, and changing mineral allocation patterns. Therefore, 100 µM also countered the drought-induced decline in total plant biomass accumulation. The application of suitable SA concentrations is an efficient tool to improve cellular homeostasis and growth of plants subjected to recurrent drought episodes.


Assuntos
Secas , Íons/metabolismo , Olea/metabolismo , Oxirredução , Folhas de Planta/metabolismo , Ácido Salicílico/farmacologia , Antioxidantes/química , Biomassa , Minerais/química , Nutrientes/química , Estresse Oxidativo , Fotossíntese/efeitos dos fármacos , Raízes de Plantas/metabolismo , Portugal , Espécies Reativas de Oxigênio/metabolismo , Água/metabolismo
18.
Plant Cell Rep ; 38(9): 1151-1163, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31152194

RESUMO

KEY MESSAGE: Piriformospora indica confers salt tolerance in tomato seedlings by increasing the uptake of nutrients such as N, P and Ca, improving K+/Na+ homoeostasis by regulating the expression of NHXs, SOS1 and CNGC15 genes, maintaining water status by regulating the expression of aquaporins. Piriformospora indica, an endophytic basidiomycete, has been shown to increase the growth and improve the plants tolerance to stressful conditions, especially salinity, by establishing the arbuscular mycorrhiza-like symbiotic relationship in various plant hosts. In the present research, the effect of NaCl treatment (150 mM) and P. indica inoculation on growth, accumulation of nutrients, the transcription level of genes involved in ionic homeostasis (NHXs, SOS1 and CNGC15) and regulating water status (PIP1;2, PIP2;4, TIP1;1 and TIP2;2) in roots and leaves of tomato seedlings were investigated. The P. indica improved the uptake of N, P, Ca and K, and reduced Na accumulation, and had no significant effect on Cl accumulation in roots and leaves. The endophytic fungus also increased in K+/Na+ ratio in roots and leaves of tomato by regulating the expression of NHX isoforms and upregulating SOS1 and CNGC15 expression. Salinity stress increased the transcription of PIP2;4 gene and reduced the transcription of PIP1;2, TIP1;1 and TIP2;2 genes compared to the control treatment. However, P. indica inoculation upregulated the expression of PIP1;2 and PIP2;4 genes versus non-inoculated plants but did not have a significant effect on TIP1;1 and TIP2;2 expression. These results conclude that the positive effects of P. indica on nutrients accumulation, ionic homeostasis and water status lead to the increased salinity tolerance and the improved plant growth under NaCl treatment.


Assuntos
Basidiomycota/fisiologia , Lycopersicon esculentum/microbiologia , Nutrientes/metabolismo , Potássio/metabolismo , Sódio/metabolismo , Água/metabolismo , Homeostase , Lycopersicon esculentum/genética , Lycopersicon esculentum/fisiologia , Salinidade , Tolerância ao Sal , Estresse Fisiológico , Simbiose
19.
Plant Physiol Biochem ; 139: 724-730, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31055133

RESUMO

Tree trunks not only provide physical support for canopy leaves but also supply and store water for transpiration. However, the relationships between trunk hydraulic properties and canopy leaf physiology in tropical trees are not well-understood. In this study we concurrently measured morning and midday canopy leaf photosynthesis (A), stomatal conductance (gs), and leaf water potentials (ΨL) in 40 tropical trees representing 14 species at the beginning of the rainy season in Xishuangbanna, Southwest China. We also measured trunk sapwood capacitance (C), wood density, and sap flux density to assess their association with canopy leaf physiology. Among the 14 studied species, only three and four species did not show a significant midday reduction in A and gs respectively. The diurnally maximum A and gs were significantly positively related to sapwood hydraulic capacitance, maximum sap flux density (midday), and sap flux density at 11:00. Those species with lower wood density and higher C showed a lower reduction in ΨL at midday, whereas, species with high C, and large values of maximum sap flux density also showed high carbon assimilation at midday. Our results provide new insights into the close coordination between canopy physiology and trunk sapwood hydraulic properties in tropical trees.


Assuntos
Fotossíntese/fisiologia , Folhas de Planta/metabolismo , Água/metabolismo
20.
World J Microbiol Biotechnol ; 35(6): 81, 2019 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-31134389

RESUMO

TiO2 nanoparticles (TiO2NPs) is one of the most widely used nanomaterials. Arbuscular mycorrhizal fungi (AMF) are an important and widely distributed group of soil microorganisms, which promote the absorption of nutrients by host plants and increase their tolerance to contaminants. However, the effects and mechanisms of AMF on plant TiO2NPs tolerance in wetland habitats are not clear. In this experiment, under the conditions of three soil moisture contents (drought 50%, normal 70% and flooding 100%) and four TiO2NPs concentrations (0, 100, 200 and 500 mg kg-1), the effects of Funneliformis mosseae on the growth, antioxidant enzyme activities, osmotic substances and the absorption and accumulation of Ti in the Phragmites australis (reed) seedlings were studied. The results showed that the inoculation of F. mosseae under three moisture content conditions significantly increased the plant nutrition and root activities of reeds. Compared with the non-inoculated control, inoculation with F. mosseae increased the activities of antioxidant enzymes, the contents of chlorophyll, proline, soluble protein, and free amino acids, and significantly reduced the contents of malondialdehyde (MDA) and reactive oxygen species (ROS) of leaves. The accumulating ability of inoculated reeds to Ti was significantly higher than that of non-inoculated controls (P < 0.05), and inoculation of F. mosseae changed the distribution of Ti in reeds, increased the accumulation of Ti in roots. It's confirmed that inoculation of F. mosseae under three water conditions could improve the plant growth and nutrition, the activities of antioxidant enzymes, and enhance the reeds tolerance to TiO2NPs in this study.


Assuntos
Glomeromycota/fisiologia , Nanopartículas/toxicidade , Poaceae/efeitos dos fármacos , Poaceae/microbiologia , Plântula/crescimento & desenvolvimento , Estresse Fisiológico , Titânio/toxicidade , Água/metabolismo , Aminoácidos/metabolismo , Antioxidantes/metabolismo , Clorofila/metabolismo , Secas , Tolerância a Medicamentos , Malondialdeído/metabolismo , Osmose , Desenvolvimento Vegetal , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Poaceae/crescimento & desenvolvimento , Prolina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Plântula/efeitos dos fármacos , Plântula/microbiologia , Microbiologia do Solo , Áreas Alagadas
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