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1.
Bioresour Technol ; 326: 124711, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33550212

RESUMO

This study presents techno-economic evaluation of a biorefinery concept using biodiesel industry by-products (sunflower meal and crude glycerol) to produce poly(3-hydroxybutyrate) (PHB), crude phenolic extracts (CPE) and protein isolate (PI). The PHB production cost at two annual production capacities ($12.5/kg for 2,500 t PHB/year and $7.8/kg for 25,000 t PHB/year) was not cost-competitive to current PHB production processes when the revenues derived from co-products were not considered. Sensitivity analysis projected the economic viability of a biorefinery concept that could achieve a minimum selling price of $1.1/kg PHB similar to polypropylene. The annual PHB production capacity and the identification of marketable end-uses with respective market prices for the co-products CPE and PI were crucial in attaining process profitability. Greenhouse gas emissions (ca. 0.64 kg CO2-eq/kg PHB) and abiotic depletion potential (61.7 MJ/kg PHB) were lower than polypropylene. Biorefining of sunflower meal and crude glycerol could lead to sustainable PHB production.


Assuntos
Biocombustíveis , Helianthus , Ácido 3-Hidroxibutírico , Hidroxibutiratos , Poliésteres
2.
Ecotoxicol Environ Saf ; 210: 111906, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33429318

RESUMO

In the present work, the effect of seed pre-soaking with gallic acid (GA; 3,4,5-triphydroxyl-benzoic acid) in conferring subsequent tolerance to Cd stress in sunflower (Helianthus annuus) seedlings was investigated. Exposing sunflower seedlings to increasing Cd concentrations (5, 10 and 20 µM) caused a gradual decrease in root and shoot biomass and increased the metal accumulation in both organs. Seed pretreatment with 75 µM GA significantly restricted Cd uptake, markedly alleviated Cd-induced plant growth inhibition, and mitigated the oxidative damages caused by this metal, as compared to plants directly exposed to Cd. GA pre-soaking prior to Cd stress also enhanced catalase, ascorbate peroxidase and glutathione reductase activities, while inhibiting that of superoxide dismutase. This was associated with increased levels of total thiols and glutathione along with a decreased level of oxidized glutathione in leaves. Moreover, GA pre-soaking led to changes in leaf fatty acid composition of seedlings challenged with Cd, as evidenced by the higher total lipid content and lipid unsaturation degree. As a whole, this study provides strong arguments highlighting the potential role of GA as a growth promoter for sunflower seedlings submitted to Cd stress, notably by boosting the antioxidant defense system and improving leaf membrane stability.


Assuntos
Antioxidantes/farmacologia , Cádmio/toxicidade , Ácido Gálico/farmacologia , Helianthus/efeitos dos fármacos , Ascorbato Peroxidases/metabolismo , Catalase/metabolismo , Tolerância a Medicamentos , Glutationa/metabolismo , Helianthus/crescimento & desenvolvimento , Helianthus/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Superóxido Dismutase/metabolismo
3.
Food Chem ; 340: 127926, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32919357

RESUMO

This paper provides a method for the quantification of sterols in different types of calf feedstuffs based on soy, sunflower, hay, calf feed and a mixture of all of them. The free fraction and the total sterolic fraction, after saponification and acidic hydrolysis of the samples, are extracted by solvent and the sterols are identified/quantified by reversed phase HPLC coupled to tandem mass spectrometry by atmospheric pressure chemical ionization. After the recovery evaluation, the method is validated in terms of linearity (coefficient of determination R2), repeatability (coefficient of variation RSD), limit of detection and quantification. In most of the cases, the most representative phytosterol is ß-sitosterol, followed by campesterol or stigmasterol and by other minor sterols such as fucosterol, and Δ-5-avenasterol. In addition, also cholesterol and ergosterol, if present, are evaluated in all the samples. As far as we know, very little information is available on the investigated feeds, which are commonly used on farms. The results of this survey were compared to other studies, if present in literature, showing good agreement. The proposed method resulted to be simple, fast and suitable for application to other sterols, feedstuffs and derived foods. The knowledge of the sterolic content and composition is getting more and more important, both in terms of comprehension of the vegetal biochemistry and as basis for sterolomic studies.


Assuntos
Ração Animal/análise , Fitosteróis/análise , Animais , Pressão Atmosférica , Bovinos , Colesterol/análogos & derivados , Cromatografia Líquida de Alta Pressão/métodos , Ergosterol/análise , Helianthus , Sitosteroides/análise , Soja/química , Estigmasterol/análogos & derivados , Estigmasterol/análise , Espectrometria de Massas em Tandem
4.
Chemosphere ; 262: 127735, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32777610

RESUMO

Despite the restriction of the use of neonicotinoids in the EU, including thiamethoxam and clothianidin, the debate over their risk on honey bees has not been fully settled. This study presents results of a three-year study working with 180 honey bee colonies in ten replicates. Colonies were sorted into three treatments (60 colonies per treatment) exposed to sunflower blooms grown from seeds treated with thiamethoxam, clothianidin and a non-treated control. Each colony was assessed at six moments: one before to exposition to sunflower, two during the exposition (short-time risk), two after exposition (medium-time risk) and one after wintering (long-time risk). The health and development of the colonies were assessed by monitoring adult bee population, brood development, status of the queen, food reserves and survival. No significant difference among treatments when raw data was considered. However, when evolution from initial status of the colony was evaluated, a significant difference was observed from the first week of exposure to sunflower blooms. In this period, the number of adult bees and the amount of brood were slightly lower in the bee hives exposed to neonicotinoids, although such differences disappeared in subsequent evaluations. The concentration of residues in samples of beebread and adult bees was at the level of ng·g-1. Magnitude of the effect of the treatment factor on the variability of colony health and development related parameters was low. The most important factor was the hive, followed by the replicate and year, and to a lesser extent the initial strength of the colonies.


Assuntos
Abelhas/efeitos dos fármacos , Guanidinas/toxicidade , Helianthus , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Sementes/efeitos dos fármacos , Tiametoxam/toxicidade , Tiazóis/toxicidade , Animais , Abelhas/fisiologia , Ecotoxicologia/métodos , Flores , Guanidinas/análise , Helianthus/efeitos dos fármacos , Inseticidas/análise , Neonicotinoides/análise , Resíduos de Praguicidas/análise , Polinização , Própole/análise , Sementes/química , Espanha , Tiametoxam/análise , Tiazóis/análise
5.
Chemosphere ; 265: 129086, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33340834

RESUMO

The use of phytoextraction plant species to accumulate soil metals into harvestable plant parts is a method used for managing soils with high cadmium (Cd). We evaluated three Cd accumulating species recently recommended for such use in cacao farms where Cd removal is needed to maintain markets: Helianthus annuus (sunflower), Brassica napus (rapeseed), and Chyrsopogon zizanioides (vetiver). Plants were grown in two greenhouse pot experiments with different Cd-spiked growth media: (sand plus perlite) and a natural soil. Plant total Cd and Cd uptake in shoot biomass of all species, across both experiments, increased linearly with increasing amounts of added Cd. Rapeseed had the highest plant total Cd and sunflower had the highest Cd uptake in shoot biomass. The highest application of Cd corresponded to the highest plant total Cd and shoot biomass Cd uptake, regardless of species. The bioconcentration factor (BCF) for each species increased in a curvilinear manner with added Cd, with maximum BCF values for plants grown in the sand and perlite matrix at 2.5 mg kg-1 added Cd and in the natural soil at 5.0 mg kg-1 added Cd. We conclude that the Cd uptake (shoot biomass only) capability of the three species examined is greatest for sunflower given its increased uptake with Cd additions, its BCF value > 1, and lack of observed visual Cd toxicity symptoms, fungus and insect damage. Although these species had BCF >1, the potential annual removal of Cd would have been too small to support a meaningful phytoextraction practice.


Assuntos
Brassica napus , Helianthus , Poluentes do Solo , Biodegradação Ambiental , Cádmio/análise , Solo , Poluentes do Solo/análise
6.
Chemosphere ; 262: 127809, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32781331

RESUMO

Plant growth regulators (PGRs) are widely used in agricultural activities and have the potential to improve plant growth and plant tolerance against metal stress. PGR-assisted phytoextraction is now an effective and inexpensive method for enhancing the plant removal of toxic metals from soil. In this study, we conducted experiments to determine the effects of PGR treatments on soil uranium (U) and cadmium (Cd) removal by sunflowers as well as their stress response to U and Cd contamination. We found that the plant growth was inhibited by combined U and Cd stress in sunflowers compared with that of the control; however, the application of exogenous PGR had reduced the combined U and Cd stress by stimulating photosynthesis, decreasing the levels of active oxygen and lipid peroxidation, and enhancing the activity of the antioxidant defence systems. Exogenous PGR also increased the uptake of U and Cd by sunflowers and therefore, improved their U and Cd remediation efficiency. Moreover, indoleacetic acid (IAA) was the most effective PGR at removing U and Cd in the soil; the U and Cd removal efficiency was 484.21% and 238.85% higher in the 500 mg L-1 IAA application compared with that of the control without PGR application, respectively. Furthermore, none of the PGR treatments significantly influenced the available U and Cd contents in soil. Our results, therefore, may provide some detailed understanding on the technologies for the sustainable remediation of U and Cd contaminated soil by the combination of PGR treatments and phytoextraction.


Assuntos
Biodegradação Ambiental , Cádmio/toxicidade , Helianthus/fisiologia , Reguladores de Crescimento de Planta/farmacologia , Poluentes do Solo/toxicidade , Urânio/toxicidade , Cádmio/metabolismo , Helianthus/crescimento & desenvolvimento , Ácidos Indolacéticos , Solo , Poluentes do Solo/análise , Urânio/metabolismo
7.
Ecotoxicol Environ Saf ; 207: 111315, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32947213

RESUMO

Growing environmental concern regarding multi elements-contaminated soils reveals the necessity of paying more attention to environmentally friendly remediation techniques such as phytoremediation. A large number of factors influences phytoremediation of potentially toxic elements (PTEs) and investigation on a variety of these factors need appropriate statistical approaches such as "Taguchi optimization" which effectively decreases time and cost of experiments. In the present study, based on the Taguchi optimization method, the effects of several biological (plant type and mycorrhizal fungi (AMF)) and chemical (chelating agents, surfactants and organic acids) factors, on the phytoremediation of soils contaminated with zinc (Zn), lead (Pb), cadmium (Cd) and nickel (Ni) were investigated. The goal was to find out the most effective factors as well as the best level for each factor. The values of dry weights in roots and aerial parts of the studied plants were in orders of maize > sorghum > sunflower and sorghum > maize > sunflower, respectively. AMF was the main factor in increasing dry weight of shoots. Inoculation of AMF caused increases in root and shoot uptake of some PTEs. RESULTS: showed that phytoremediation of PTEs is element-dependent; as Zn showed the highest translocation factor (TF) and bioconcentration factor (BCF) values, while Ni showed the lowest ones and the intermediate values belonged to Pb and Cd. These results show the diverse distribution of elements in plant parts, as Zn and Ni were mostly accumulated in shoot and root, respectively. Although different factors caused impacts on phytoremediation criteria, the role of plant type in the phytoremediation of PTEs was at the first rank. Mean TF of PTEs in sunflower was 6.3 times that of maize. Sunflower showed high TF value for the four elements and translocated most of the PTEs from root to the aerial parts demonstrating phytoextraction as the main mechanism in this plant. Maize and sorghum, however, showed low TF and accumulated most of PTEs in their roots revealing phytostabilization as the main mechanism. In general, it can be concluded that plant type was the most influential factor in the phytoremediation of PTEs followed by EDTA and AMF. Taguchi optimization revealed the appropriateness and significance of different chemical and biological treatments on phytoremediation criteria of different elements.


Assuntos
Biodegradação Ambiental , Poluentes do Solo/metabolismo , Cádmio/análise , Poluentes Ambientais , Recuperação e Remediação Ambiental , Helianthus/microbiologia , Micorrizas/química , Níquel , Solo , Poluentes do Solo/análise , Sorghum , Zea mays , Zinco/análise
8.
Chemosphere ; 263: 128195, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297160

RESUMO

Natural occurring metal-tolerant microbial population have replaced conventional expensive metal remediation approach since the last few years. The present study focuses on investigating the potential of a copper-tolerant plant growth promoting rhizobacterial strain Brevundimonas diminuta MYS6 for Cu bioremediation, plant growth promotion and Cu uptake in Helianthus annuus L. Box-Behnken Design of response surface methodology optimized the influencing parameters such as pH, temperature and Cu concentration. At optimized conditions of pH (5), temperature (32.5 °C) and Cu concentration (250 mg/L), the rhizobacteria followed a sigmoid growth curve pattern with maximum Cu removal of 94.8% in the stationary phase of growth. Cu exposed Brevundimonas diminuta MYS6 produced increased EPS (18.6%), indicating their role in internal defence against Cu stress. The FTIR analysis suggested the role of carboxylic acids, alcohols and aliphatic amine groups in Cu bioremoval. Furthermore, the results of pot experiments conducted with Helianthus annuus L. var. CO4 and Brevundimonas diminuta MYS6 showed enhanced plant growth and Cu uptake. The rhizobacteria increased root and shoot length, fresh and dry plant biomass and leaf chlorophyll by 1.5, 1.7, 9.9, 15.8 and 2.1 fold. The plant biomass mediate enhanced Cu uptake in roots and shoots was found to be 2.98 and 4.1 folds higher when compared to non-inoculated treatment. Henceforth the results of the study evidence the rhizobacterial strain Brevundimonas diminuta MYS6 as an efficient bio-inoculant for copper remediation.


Assuntos
Helianthus , Poluentes do Solo , Biodegradação Ambiental , Caulobacteraceae , Cobre/análise , Raízes de Plantas/química , Poluentes do Solo/análise
9.
Proc Natl Acad Sci U S A ; 117(52): 33351-33357, 2020 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-33318205

RESUMO

The contributions of crop wild relatives (CWR) to food security depend on their conservation and accessibility for use. The United States contains a diverse native flora of CWR, including those of important cereal, fruit, nut, oil, pulse, root and tuber, and vegetable crops, which may be threatened in their natural habitats and underrepresented in plant conservation repositories. To determine conservation priorities for these plants, we developed a national inventory, compiled occurrence information, modeled potential distributions, and conducted threat assessments and conservation gap analyses for 600 native taxa. We found that 7.1% of the taxa may be critically endangered in their natural habitats, 50% may be endangered, and 28% may be vulnerable. We categorized 58.8% of the taxa as of urgent priority for further action, 37% as high priority, and 4.2% as medium priority. Major ex situ conservation gaps were identified for 93.3% of the wild relatives (categorized as urgent or high priority), with 83 taxa absent from conservation repositories, while 93.1% of the plants were equivalently prioritized for further habitat protection. Various taxonomic richness hotspots across the US represent focal regions for further conservation action. Related needs include facilitating greater access to and characterization of these cultural-genetic-natural resources and raising public awareness of their existence, value, and plight.


Assuntos
Conservação dos Recursos Naturais , Produtos Agrícolas/fisiologia , Produtos Agrícolas/classificação , Geografia , Helianthus/fisiologia , Estados Unidos
10.
Int J Biometeorol ; 64(12): 2153-2160, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32902724

RESUMO

Leaf diseases affect crop yields. In sunflower crops, leaf spot severity can reach 100%, but the magnitude of the yield loss caused by the disease is not known. This study aimed to evaluate the effect of Alternaria and Septoria leaf spot severity on sunflower yield across different years in a humid subtropical climate. We conducted 37 experiments in Santa Maria, RS, Brazil, over 7 years. The hybrids Embrapa 122, Helio 358, Aguará 03, and Altis 99 were sowed and managed according to national crop recommendations. Severity assessments for Alternaria and Septoria spots were performed at 2- to 7-day intervals using a diagrammatic scale. We evaluated the effects of Alternaria and Septoria leaf spot severity on crop yield using upper limit graphs. The 37 experiments comprised 13 normal season crops (August to October) and 24 late season crops (November to February). The results were also classified according to the contemporaneous phases of the ENSO (El Niño Southern Oscillation): El Niño, La Niña, and Neutral. In normal season crops, severities of up to 24% do not result in yield decrease. After this, each 1% increment in disease severity produces a decrease of 66 kg ha-1 on sunflower yield. In late season crops, the reduction in productivity occurs at severities greater than 34%, with a decrease of 50 kg ha-1 for each 1% increase in combined disease severity. The highest severity values and lowest yields, both in the normal and late season crops, occurred in El Niño years.


Assuntos
Helianthus , Alternaria , Brasil , El Niño Oscilação Sul , Estações do Ano
11.
Exp Parasitol ; 218: 107984, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32871143

RESUMO

The fascioliasis is a parasitic disease of importance in veterinary medicine and public health. For this parasitosis, the treatment by synthetic fasciolicides is used and due to their intense use although they have been shown less effective because of the establishment of resistant Fasciola hepatica population to these drugs, with a global concern. The use of derived products of plants with biological activity has been shown promising in the control of parasites. In this context, we evaluated the chemical composition and action of ovicidal in vitro fixed oil of Helianthus annuus L. (FOH) and essential oil of Cuminum cyminum L. (EOC), as well as their combination (FOH + EOC) of F. hepatica. In the assay in vitro of F. hepatica were submitted to different concentrations of oils, such as FOH (2.3 mg/mL + 0,017 mg/mL); EOC (2.07 mg/mL + 0,004 mg/mL) and the combination of (1.15 mg/mL + 1.03 mg/mL to 0,0085 mg/mL + 0,008 mg/mL) as well as a positive control of thiabendazole (0.025 mg/mL) and a negative control with distilled water and tween. The identification of the majority chemical compounds was performed by gas chromatography. The -cell viability of the oils was tested in MDBK cellular line by the MTT method. The majority compounds in the FOH were the linoleic (53.6%) and oleic (35.85%) unsaturated fatty acids, and the majority phytochemicals compounds in the EOC were the Cumaldehyde (26.8%) and the 2-Caren 10-al (22.17%). The EOC and the combination presented effectiveness of 99% (±1) and of 94% (±1) in the concentration of 0.03 mg/mL and 0.035 mg/mL+0.03 mg/mL, respectively, and the FOH was insufficiently active as ovicidal. The cell viability at this concentration of EOC was 93%. From the results above we could infer that the EOC is promising as a new alternative for the fascioliasis control.


Assuntos
Cuminum/química , Fasciola hepatica/efeitos dos fármacos , Helianthus/química , Óleos Voláteis/farmacologia , Óleos Vegetais/farmacologia , Análise de Variância , Animais , Anti-Helmínticos/farmacologia , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Gasosa , Cães , Combinação de Medicamentos , Indicadores e Reagentes , Fígado/parasitologia , Células Madin Darby de Rim Canino/efeitos dos fármacos , Óleos Voláteis/química , Óvulo/efeitos dos fármacos , Óleos Vegetais/química , Sais de Tetrazólio , Tiabendazol/farmacologia
12.
Ecotoxicol Environ Saf ; 205: 111145, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32846296

RESUMO

This study characterizes sunflower response to the levels of Cd encountered in moderately Cd-polluted soils. Two sunflower cultivars differing in their ability to sequestrate Cd in roots were exposed to low concentrations of Cd (0.5 nM or 100 nM) in hydroponics and sampled after 18 days (258 degree-days) when ten leaves were fully expanded. Plant growth, Cd uptake and partitioning among organs were monitored along with the ionomic (ICP-MS) and the metabolic (1H-NMR) composition of the xylem sap. Sunflower tolerance to Cd differed between the two cultivars. The cultivar with the highest ability to sequestrate Cd in roots (Kapllan) was more tolerant to Cd than the one with the lowest ability (ES RICA). The 23% penalization of plant growth observed at 100 nM in cultivar ES RICA was associated with reduced xylem loading fluxes of soluble sugars, perhaps pointing to disruption of carbohydrate metabolism. Retention of Cd in the stem was higher at 100 nM than at 0.5 nM in the Cd-sensitive cultivar ES RICA, which can be seen as a sunflower strategy to restrict the amount of Cd delivered to the leaves under Cd stress. No direct connection was found between the speciation of Cd in the xylem sap and the Cd translocation efficiency, although significant changes in the free ionic fraction of Cd were observed between the two cultivars at 0.5 nM. The relevance of these results in promoting the use of sunflower in phytomanagement of Cd-polluted soils is discussed.


Assuntos
Cádmio/metabolismo , Helianthus/metabolismo , Hidroponia , Transporte Biológico , Desenvolvimento Vegetal , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Xilema/metabolismo
13.
Environ Res ; 188: 109886, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32846652

RESUMO

Heavy metal contamination of soils is a serious issue with various consequences in Hunan Province. Here, we aimed to determine the effect and action mechanisms of lychee biochar on the remediation of Pb, Cd, As, and Zn from soil using sunflower (Helianthus annuus). Different amounts of lychee biochar (2.5, 5, and 10%) were added to heavy metal-contaminated soil in the Shuikoushan mining area, Hunan Province. The effects of biochar on the biomass of sunflower plants, and the accumulation and distribution of Pb, Cd, As, and Zn in sunflower plants, and changes in Pb, Cd, As, and Zn concentrations in the rhizosphere soil were studied. The application of biochar stimulated the growth of the sunflower plants, with the maximum biomass recorded in the 5% biochar treatment; however, above this level, biochar inhibited plant growth. Pb, Cd, As, and Zn in sunflower plants were redistributed with biochar addition. The concentration of Pb, Cd, As, and Zn in the leaves and receptacles of sunflower plants increased with biochar application, but their concentration in the roots, stems, and seeds significantly decreased compared with the control. The total amount of accumulated Pb, Cd, and As in sunflower plants increased by 22.9-58.9%, 15.8-42.3%, and 67.9-110%, respectively, compared with that in the control. In the biochar treatments, the total amount of accumulated Zn in sunflowers decreased by 13.8-37.2%, compared with that in the control. The accumulated Pb, Cd, and As in sunflower plants have an antagonistic effect on Zn required by sunflowers. The sunflower plants significantly reduced the concentration of Pb, Cd, As, and Zn in contaminated soil (P < 0.05), which decreased by 12.4, 11.0, 4.35, and 8.17%, respectively, compared with that before planting sunflower. The addition of biochar in heavy metal-contaminated soil significantly enhanced the heavy metal-remediation effect of sunflower. Compared with the control (0% biochar), 10% biochar application decreased the Pb, Cd, As, and Zn concentrations in the rhizosphere of sunflower plants, by 40.6, 31.6, 35.4, and 30.8%, respectively. In conclusion, lychee biochar enhanced the remediation of heavy metals in contaminated soil.


Assuntos
Helianthus , Litchi , Metais Pesados , Poluentes do Solo , Biodegradação Ambiental , Carvão Vegetal , Metais Pesados/análise , Solo , Poluentes do Solo/análise
14.
PLoS One ; 15(8): e0237318, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32804952

RESUMO

The mirid bug Lygus pratensis is an important pest of cotton, and is primarily managed through insecticide application. In this study, conducted in Xinjiang (China), we assessed the relative attractiveness of sunflower (Helianthus annuus) to L. pratensis adults in local cotton plots from 2015-2016 and quantified the associated contribution of inter-planted sunflower strips to suppress field-level L. pratensis populations from 2016-2017. Field-plot trials showed that among six combinations of two sunflower varieties (XKZ6 and SH363) and three planting dates (early-, middle- and late-planted), adult abundance of L. pratensis was highest on early-planted XKZ6 and attained 3.7-5.8 times higher levels than in neighboring cotton plots. In commercial cotton fields, the combined deployment of sunflower strips at field edges and the periodic application of insecticides directed to those strips was found to (1) reduce the mean abundance of L. pratensis population on cotton by 41.9-44.0%, (2) lower the rate of cotton leaf damage by 27.3-30.6% and boll damage by 44.8-46.0%, and (3) increase the number of mature bolls by 7.5%-8.0%. Our work emphasizes how sunflower can be an effective trap crop for L. pratensis and that the establishment of sunflower strips could contribute to its effective and environmentally-sound management in cotton crops.


Assuntos
Proteção de Cultivos/métodos , Produtos Agrícolas/parasitologia , Gossypium/parasitologia , Helianthus/parasitologia , Heterópteros/fisiologia , Animais , China , Comportamento Alimentar , Folhas de Planta/parasitologia
15.
J Food Sci ; 85(9): 2866-2878, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32790192

RESUMO

The objective of this study was to evaluate the capacity of recovered sunflower waxes (RW) to be used as a structuring agent of oleogel emulsions in comparison with commercial sunflower waxes (CW). RW were recovered from filter cake with a simple hexane extraction procedure. For this purpose, oleogel-based emulsions were prepared using 2%, 3.5%, and 5% w/w wax in oleogel and characterized using several physicochemical techniques in order to evaluate the potential of these materials to develop products with functionality similar to commercial margarines. The total wax esters content of RW was similar to that of the CW and was mainly composed of wax esters with more than 44 carbon atoms (crystallizable waxes). Polarized light and scanning electron microscopy showed that RW produced emulsions with more intricate crystalline networks composed of smaller platelets than CW. The melting enthalpy was greater in CW emulsions than RW emulsions, which was in agreement with the thermal behavior found for CW and RW. The oil binding capacity of CW oleogel emulsions was higher than the RW ones, and this property improved with the increase in wax concentration. Likewise, the elastic behavior, as well as hardness and adhesiveness, increased with the wax content as a result of a greater amount of microstructural elements composing the network of these semisolid materials. The oleogel emulsions stability was monitored for 2 months at room temperature. The increase of CW concentration slowed down the coalescence process, but this behavior was not observed for RW emulsions. Obtained results demonstrated that RW oleogel emulsions have the potential to replace the functionality of soft spreadable products. PRACTICAL APPLICATION: Wax esters are organogelators that have been shown to successfully gel liquid oil at low concentrations. In this work, we are interested in evaluating the potential of sunflower waxes recovered from filter cake, a waste generated during refined oil production, to structure oil and produce oil-in-water emulsions with functionality similar to commercial margarines. With this, it is sought not only the development of healthier fats but also the use of wastes to generate more sustainable products.


Assuntos
Helianthus/química , Extratos Vegetais/química , Ceras/química , Emulsões/química , Ésteres/química , Margarina/análise , Compostos Orgânicos/química , Extratos Vegetais/isolamento & purificação , Ceras/isolamento & purificação
16.
Nature ; 584(7822): 602-607, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32641831

RESUMO

Species often include multiple ecotypes that are adapted to different environments1. However, it is unclear how ecotypes arise and how their distinctive combinations of adaptive alleles are maintained despite hybridization with non-adapted populations2-4. Here, by resequencing 1,506 wild sunflowers from 3 species (Helianthus annuus, Helianthus petiolaris and Helianthus argophyllus), we identify 37 large (1-100 Mbp in size), non-recombining haplotype blocks that are associated with numerous ecologically relevant traits, as well as soil and climate characteristics. Limited recombination in these haplotype blocks keeps adaptive alleles together, and these regions differentiate sunflower ecotypes. For example, haplotype blocks control a 77-day difference in flowering between ecotypes of the silverleaf sunflower H. argophyllus (probably through deletion of a homologue of FLOWERING LOCUS T (FT)), and are associated with seed size, flowering time and soil fertility in dune-adapted sunflowers. These haplotypes are highly divergent, frequently associated with structural variants and often appear to represent introgressions from other-possibly now-extinct-congeners. These results highlight a pervasive role of structural variation in ecotypic adaptation.


Assuntos
Ecótipo , Haplótipos , Helianthus/genética , Aclimatação/genética , Alelos , Flores/genética , Helianthus/anatomia & histologia , Helianthus/crescimento & desenvolvimento , Filogenia , Sementes/genética
18.
Environ Sci Pollut Res Int ; 27(31): 38537-38544, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32623673

RESUMO

In a context of scarcity of good quality water, reuse is a mandatory practice to increase water availability, thus allowing the exploitation of more cropland. Although several studies have evaluated the hydric potential of domestic gray water to promote the economic and environmental sustainability of agriculture, the focus of this study was to evaluate the application of this effluent on an ornamental plant, the sunflower. The experiment was conducted in a protected environment using a completely randomized block design with split plots and four replicates. Irrigation solutions containing different mixtures of treated gray water effluent (TGW) and drinking water (DW) (100% DW, 25% TGW + 75% DW, 50% TGW + 50% DW, 75% TGW + 25% DW, and 100% TGW) were arranged in the plots, while the ornamental sunflower cultivars (Bonito de Outono Sortido and Sol Vermelho) were arranged in the split plots. Irrigation with treated gray water did not affect the growth of the plants and the quality of the flowers until the dilution of 55% in drinking water. The cultivar Sol Vermelho showed better plant growth and flower quality when fertigated with dilutions of treated gray water. The principle of mixing fresh with gray water, applied to the production of ornamental sunflowers, allows obtaining flowers of good quality while saving drinking water and decreasing the deposition of effluents in the environment.


Assuntos
Helianthus , Agricultura , Produtos Agrícolas , Água
19.
Gene ; 758: 144950, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32683078

RESUMO

Sunflower (Helianthus annuus L.) is an important oil crop, the secondary metabolites of it include many compounds such as flavonoids and lignin. However, the research on the biosynthesis of phenolic compounds in sunflowers is still scarce. Cinnamate 4-hydroxylase (C4H) belongs to the cytochrome P450-dependent monooxygenase family and is involved in the synthesis of many phenolic compounds, but C4H in sunflowers has not yet been cloned and functionally characterized. In this study, we screened three C4H genes from the sunflower transcriptome and genomic databases, named HaC4H1, HaC4H2, and, HaC4H3, respectively. In heterologous expression experiments, we had improved a method from previous studies by the addition of restriction sites to make it easier to express multiple C4H functions and suitable for in vitro activity verification. HaC4Hs without the N-terminal membrane anchor region was fused with a redox partner of Arabidopsis thaliana cytochrome P450 enzyme (CYP450) by the method and functionally expressed in E. coli and the results showed that these three enzymes catalyzed the formation of p-coumaric acid. To further investigate whether our fusion protein approach is applicable to other C4Hs, we used this method to explore the functions of C4H from Peucedanum praeruptorum and Angelica decursiva, and they can also convert trans-cinnamic acid to p-coumaric acid. The gene expression profile showed that all three HaC4H genes showed the highest transcription levels in the roots and might be up-regulated by MeJA. In summary, these results reveal the function of HaC4Hs in sunflower and provide a simpler way to explore C4H and even other cytochrome P450 enzymes in prokaryotic expression systems.


Assuntos
Helianthus/enzimologia , Propionatos/metabolismo , Transcinamato 4-Mono-Oxigenase/genética , Transcinamato 4-Mono-Oxigenase/metabolismo , Sequência de Aminoácidos , Angelica/genética , Apiaceae/genética , Arabidopsis/genética , Clonagem Molecular , Proteínas Recombinantes de Fusão/genética , Alinhamento de Sequência , Transcriptoma/genética
20.
Ecotoxicol Environ Saf ; 203: 110964, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32678754

RESUMO

Soil salinization is the most common abiotic stress limiting agricultural productivity worldwide. Recent research has suggested that the application of silicon (Si) has beneficial effects against salt stress in sorghum (Sorghum bicolor L. Moench) and sunflower (Helianthus annuus L.) by regulating the antioxidant system, mineral nutrients, and other important mechanisms. However, whether these effects can be achieved through foliar application of Si, or whether Si application affects Si-accumulating (e.g., sorghum), and intermediate-Si-accumulating (e.g., sunflower) plant species differently, remains unclear. This study investigated different methods of Si application in attenuating the detrimental effects of salt stress, based on the biological responses of two distinct species of Si accumulators, under greenhouse conditions. Two pot experiments were designed as a factorial (2 × 4), randomized complete blocks design (RCBD) with control and salt-stress groups (0 and 100 mmol.L-1 NaCl), and four Si-treatment groups: control (no Si), foliar application (28.6 mmol.L-1), root application (2 mmol.L-1), and combined foliar and root applications. Our results showed that the harmful effects of salt stress were attenuated by Si treatments in both plant species, which decreased Na+ uptake and lipid peroxidation, and increased Si and K+ uptake, relative leaf water content, antioxidant enzyme activities, leaf area, and shoot dry matter. These results were more prominent when Si was applied via nutrient solution in the sorghum plants, and the combined foliar and root applications of Si in sunflower plants. In addition, foliar application of Si alone is an efficient alternative in attenuating the effects of salinity in both plant species when Si is not available in the growth medium. These results suggest that the Si application method plays an important role in Na+ detoxification by modifying the antioxidative defense mechanism, which could actively mediate some important physiological and biochemical processes and helps to increase the shoot dry matter production in sorghum and sunflower plants under salt stress.


Assuntos
Antioxidantes/metabolismo , Helianthus/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Estresse Salino , Silício/farmacologia , Sorghum/efeitos dos fármacos , Grão Comestível/efeitos dos fármacos , Grão Comestível/metabolismo , Helianthus/metabolismo , Componentes Aéreos da Planta/efeitos dos fármacos , Componentes Aéreos da Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Distribuição Aleatória , Salinidade , Solo/química , Sorghum/metabolismo
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