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1.
Int J Mol Sci ; 22(18)2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34576026

RESUMO

Quorum sensing (QS) is a microbial cell-cell communication mechanism and plays an important role in bacterial infections. QS-mediated bacterial infections can be blocked through quorum quenching (QQ), which hampers signal accumulation, recognition, and communication. The pathogenicity of numerous bacteria, including Xanthomonas campestris pv. campestris (Xcc), is regulated by diffusible signal factor (DSF), a well-known fatty acid signaling molecule of QS. Cupriavidus pinatubonensis HN-2 could substantially attenuate the infection of XCC through QQ by degrading DSF. The QQ mechanism in strain HN-2, on the other hand, is yet to be known. To understand the molecular mechanism of QQ in strain HN-2, we used whole-genome sequencing and comparative genomics studies. We discovered that the fadT gene encodes acyl-CoA dehydrogenase as a novel QQ enzyme. The results of site-directed mutagenesis demonstrated the requirement of fadT gene for DSF degradation in strain HN-2. Purified FadT exhibited high enzymatic activity and outstanding stability over a broad pH and temperature range with maximal activity at pH 7.0 and 35 °C. No cofactors were required for FadT enzyme activity. The enzyme showed a strong ability to degrade DSF. Furthermore, the expression of fadT in Xcc results in a significant reduction in the pathogenicity in host plants, such as Chinese cabbage, radish, and pakchoi. Taken together, our results identified a novel DSF-degrading enzyme, FadT, in C. pinatubonensis HN-2, which suggests its potential use in the biological control of DSF-mediated pathogens.


Assuntos
Acil-CoA Desidrogenase/genética , Infecções Bacterianas/genética , Ácidos Graxos/genética , Doenças das Plantas/genética , Xanthomonas campestris/genética , Acil-CoA Desidrogenase/química , Acil-CoA Desidrogenase/isolamento & purificação , Infecções Bacterianas/microbiologia , Brassica/crescimento & desenvolvimento , Brassica/microbiologia , Comunicação Celular/genética , Ácidos Graxos/metabolismo , Regulação Enzimológica da Expressão Gênica , Genoma Bacteriano/genética , Genômica , Mutagênese Sítio-Dirigida , Doenças das Plantas/microbiologia , Percepção de Quorum/genética , Raphanus/genética , Raphanus/microbiologia , Transdução de Sinais/genética , Fatores de Virulência/genética , Sequenciamento Completo do Genoma , Xanthomonas campestris/enzimologia
2.
Molecules ; 26(15)2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34361799

RESUMO

Addition of selenium or application of ultraviolet A (UVA) radiation for crop production could be an effective way of producing phytochemical-rich food. This study was conducted to investigate the effects of selenium and UVA radiation, as well as their combination on growth and phytochemical contents in broccoli microgreens. There were three treatments: Se (100 µmol/L Na2SeO3), UVA (40 µmol/m2/s) and Se + UVA (with application of Se and UVA). The control (CK) was Se spraying-free and UVA radiation-free. Although treatment with Se or/and UVA inhibited plant growth of broccoli microgreens, results showed that phytochemical contents increased. Broccoli microgreens under the Se treatment had higher contents of total soluble sugars, total phenolic compounds, total flavonoids, ascorbic acid, Fe, and organic Se and had lower Zn content. The UVA treatment increased the contents of total chlorophylls, total soluble proteins, total phenolic compounds, and FRAP. However, the Se + UVA treatment displayed the most remarkable effect on the contents of total anthocyanins, glucoraphanin, total aliphatic glucosinolates, and total glucosinolates; here, significant interactions between Se and UVA were observed. This study provides valuable insights into the combinational selenium and UVA for improving the phytochemicals of microgreens grown in an artificial lighting plant factory.


Assuntos
Brassica/crescimento & desenvolvimento , Produção Agrícola , Compostos Fitoquímicos/biossíntese , Selênio/farmacologia , Ácido Ascórbico/metabolismo , Brassica/efeitos dos fármacos , Brassica/efeitos da radiação , Flavonoides/metabolismo , Flavonoides/efeitos da radiação , Ferro/metabolismo , Fenol/metabolismo , Fenol/efeitos da radiação , Compostos Fitoquímicos/efeitos da radiação , Açúcares/metabolismo , Açúcares/efeitos da radiação , Raios Ultravioleta
3.
Science ; 373(6551): 192-197, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244409

RESUMO

Throughout development, plant meristems regularly produce organs in defined spiral, opposite, or whorl patterns. Cauliflowers present an unusual organ arrangement with a multitude of spirals nested over a wide range of scales. How such a fractal, self-similar organization emerges from developmental mechanisms has remained elusive. Combining experimental analyses in an Arabidopsis thaliana cauliflower-like mutant with modeling, we found that curd self-similarity arises because the meristems fail to form flowers but keep the "memory" of their transient passage in a floral state. Additional mutations affecting meristem growth can induce the production of conical structures reminiscent of the conspicuous fractal Romanesco shape. This study reveals how fractal-like forms may emerge from the combination of key, defined perturbations of floral developmental programs and growth dynamics.


Assuntos
Arabidopsis/anatomia & histologia , Arabidopsis/genética , Brassica/anatomia & histologia , Brassica/genética , Redes Reguladoras de Genes , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Brassica/crescimento & desenvolvimento , Flores/anatomia & histologia , Flores/genética , Flores/crescimento & desenvolvimento , Fractais , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Inflorescência/anatomia & histologia , Inflorescência/genética , Inflorescência/crescimento & desenvolvimento , Meristema/crescimento & desenvolvimento , Modelos Biológicos , Mutação , Fenótipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transcriptoma
4.
Methods Mol Biol ; 2288: 201-216, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34270013

RESUMO

Broccoli (Brassica olearecea var. italica) is a cole crop grown for its floral heads and stalks. It is rich in bioactive chemicals good for human health. Broccoli has been consumed as a vegetable since Roman times, but its production and consumption have increased significantly over the past few decades. Breeders try to develop new broccoli varieties with high yield, improved quality, and resistance to biotic and abiotic stresses. Almost all new broccoli varieties are F1 hybrids. Development of inbred broccoli lines that can be used as parents in hybrid production is a time-consuming and difficult process. Haploidization techniques can be utilized as a valuable support in broccoli breeding programs to speed up the production of genetically pure genotypes. Haploid plants of broccoli can be produced from immature male gametophytes via anther and microspore cultures with similar success rates. The most important parameters affecting the success of haploidization in broccoli are the genetic background (genotype) and the developmental stage of the microspores. Broccoli genotypes differ in their responses to androgenesis induction. The highest androgenesis response could be induced from microspores in late uninucleate and early binucleate stages. Recovery of diploid broccoli plants from haploids is possible via spontaneous and induced doubling. Doubled haploid (DH) broccoli lines are considered to be fully homozygous. Therefore, the production of DH lines is an alternative way to obtain pure inbred lines that can be utilized as parents in the development of new F1 hybrid varieties showing high levels of heterosis, high-quality heads, and uniform harvestable crop. We are using an anther culture-based haploid plant production system to develop DH broccoli lines in our broccoli breeding program. DH broccoli lines are produced from different genetic backgrounds within a year and handed to broccoli breeders.


Assuntos
Brassica/crescimento & desenvolvimento , Brassica/genética , Melhoramento Vegetal/métodos , Aclimatação/genética , Brassica/fisiologia , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Meios de Cultura/química , Diploide , Citometria de Fluxo , Flores/genética , Flores/crescimento & desenvolvimento , Haploidia , Homozigoto , Vigor Híbrido/genética , Biologia Molecular/métodos , Ploidias , Pólen/genética , Pólen/crescimento & desenvolvimento , Regeneração/genética , Técnicas de Cultura de Tecidos
5.
Theor Appl Genet ; 134(9): 2711-2726, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34089067

RESUMO

The production of a new allohexaploid Brassica crop (2n = AABBCC) is increasingly attracting international interest: a new allohexaploid crop could benefit from several major advantages over the existing Brassica diploid and allotetraploid species, combining genetic diversity and traits from all six crop species with additional allelic heterosis from the extra genome. Although early attempts to produce allohexaploids showed mixed results, recent technological and conceptual advances have provided promising leads to follow. However, there are still major challenges which exist before this new crop type can be realized: (1) incorporation of sufficient genetic diversity to form a basis for breeding and improvement of this potential crop species; (2) restoration of regular meiosis, as most allohexaploids are genetically unstable after formation; and (3) improvement of agronomic traits to the level of "elite" breeding material in the diploid and allotetraploid crop species. In this review, we outline these major prospects and challenges and propose possible plans to produce a stable, diverse and agronomically viable allohexaploid Brassica crop.


Assuntos
Brassica/genética , Cromossomos de Plantas/genética , Melhoramento Vegetal , Poliploidia , Brassica/crescimento & desenvolvimento , Fenótipo
6.
Food Microbiol ; 99: 103805, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34119098

RESUMO

This study was done to develop a method to inactivate Escherichia coli O157:H7 on radish and cabbage seeds using simultaneous treatments with gaseous chlorine dioxide (ClO2) and heat at high relative humidity (RH) without decreasing seeds' viability. Gaseous ClO2 was spontaneously vaporized from a solution containing hydrochloric acid (HCl, 1 N) and sodium chlorite (NaClO2, 100,000 ppm). Using a sealed container (1.8 L), an equation (y = 5687×, R2 = 0.9948) based on the amount of gaseous ClO2 generated from HCl-NaClO2 solution at 60 °C and 85% RH was developed. When radish or cabbage seeds were exposed to gaseous ClO2 at concentrations up to 3,000 ppm for 120 min, germination rates did not significantly decrease (P > 0.05). When seeds inoculated with E. coli O157:H7 were treated with 2,000 or 3,000 ppm of gaseous ClO2 in an atmosphere with 85% RH at 60 °C, populations (6.8-6.9 log CFU/g) on both types of seeds were decreased to below the detection limit for enrichment (-0.5 log CFU/g) within 90 min. This study provides useful information for developing a decontamination method to control E. coli O157:H7 and perhaps other foodborne pathogens on plant seeds by simultaneous treatment with gaseous ClO2 and heat at high RH.


Assuntos
Brassica/crescimento & desenvolvimento , Compostos Clorados/farmacologia , Descontaminação/métodos , Desinfetantes/farmacologia , Escherichia coli O157/efeitos dos fármacos , Óxidos/farmacologia , Raphanus/crescimento & desenvolvimento , Sementes/microbiologia , Brassica/microbiologia , Cloro/farmacologia , Escherichia coli O157/crescimento & desenvolvimento , Germinação/efeitos dos fármacos , Temperatura Alta , Umidade , Viabilidade Microbiana/efeitos dos fármacos , Raphanus/microbiologia , Sementes/química , Sementes/crescimento & desenvolvimento
7.
Molecules ; 26(7)2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33915910

RESUMO

Nutraceuticals and functional foods are gaining more attention amongst consumers interested in nutritious food. The consumption of foodstuffs with a high content of phytochemicals has been proven to provide various health benefits. The application of biostimulants is a potential strategy to fortify cultivated plants with beneficial bioactive compounds. Nevertheless, it has not yet been established whether the proposed higher plants (St. John's wort, giant goldenrod, common dandelion, red clover, nettle, and valerian) are appropriate for the production of potential bio-products enhancing the nutritional value of white cabbage. Therefore, this research examines the impact of botanical extracts on the growth and nutritional quality of cabbage grown under field conditions. Two extraction methods were used for the production of water-based bio-products, namely: ultrasound-assisted extraction and mechanical homogenisation. Bio-products were applied as foliar sprays to evaluate their impact on total yield, dry weight, photosynthetic pigments, polyphenols, antioxidant activity, vitamin C, nitrates, micro- and macroelements, volatile compounds, fatty acids, sterols, and sugars. Botanical extracts showed different effects on the examined parameters. The best results in terms of physiological and biochemical properties of cabbage were obtained for extracts from common dandelion, valerian, nettle, and giant goldenrod. When enriched with nutrients, vegetables can constitute a valuable component of functional food.


Assuntos
Brassica/química , Brassica/efeitos dos fármacos , Brassica/crescimento & desenvolvimento , Nutrientes/química , Valor Nutritivo/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Cromatografia Líquida , Suplementos Nutricionais/análise , Qualidade dos Alimentos , Alimento Funcional , Cromatografia Gasosa-Espectrometria de Massas , Fotossíntese , Compostos Fitoquímicos/química , Extratos Vegetais/química , Plantas Comestíveis , Característica Quantitativa Herdável
8.
J Sci Food Agric ; 101(13): 5583-5590, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33709452

RESUMO

BACKGROUND: Most countries set regulatory values for the total trace element (TE) concentrations in soil, although there is growing interest in using a risk-based approach to evaluate the bioavailable TE using dilute salt extractants or other soil parameters, including pH and organic carbon. The present study compares the current regulatory system (based on total TEs and pH) and a risk-based approach using 0.01 mol L-1 CaCl2 to estimate the bioavailable fraction. RESULTS: In total, 150 paired samples of Chinese flowering cabbages (Brassica parachinensis) and their growth soils were collected, and the total and extractable concentrations of chromium (Cr), cadmium (Cd), lead (Pb), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As) and mercury (Hg), as well as soil pH and organic matter content, were measured. No more than 3.33% of the edible parts exceeded Chinese food safety standards, even when growing in soils exceeding the current regulatory thresholds by over 50%. The total soil Cd (1.5 mg kg-1 ), as well as the extractable concentrations of Cd (0.1 mg kg-1 ), Ni (0.03 mg kg-1 ) and Zn (0.1 mg kg-1 ), are the key factors affecting the TE concentrations in B. parachinensis. CONCLUSION: Our findings suggest that the current soil regulatory guidelines for safe production of B. parachinensis are overly strict and conservative. A risk-based approach based on the extractable TE concentrations would provide a better indication for plant uptake of soil TEs and avoid the waste of farmlands that can still produce safe vegetables. Future research should focus on providing crop-specific available TE concentration guidelines to promote effective utilization of farmlands. © 2021 Society of Chemical Industry.


Assuntos
Brassica/química , Oligoelementos/análise , Arsênio/análise , Brassica/classificação , Brassica/crescimento & desenvolvimento , Cádmio/análise , China , Cromo/análise , Cobre/análise , Inocuidade dos Alimentos , Mercúrio/análise , Metais Pesados/análise , Níquel/análise , Solo/química , Poluentes do Solo/análise , Verduras/química , Verduras/classificação , Verduras/crescimento & desenvolvimento , Zinco/análise
9.
Sci Rep ; 11(1): 6494, 2021 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-33753792

RESUMO

Cross-talk between phytohormones and sugars is intensely involved in plant metabolism, growth and regeneration. We documented alterations in cytokinin (CK) homeostasis in four developmental stages during de novo shoot organogenesis (DNSO) of kohlrabi (Brassica oleracea var. gongylodes cv. Vienna Purple) seedlings induced by exogenous CKs, trans-zeatin (transZ) and thidiazuron (TDZ), added together with elevated sucrose concentration (6% and 9%). Significant impact of CK and sucrose treatment and their interaction was recorded in all investigated stages, including plantlet development before calli formation (T1 and T2), calli formation (T3) and shoot regeneration (T4). Results showed remarkable increase in total CK levels for transZ treatment, particularly with 9% sucrose. This trend was observed for all physiological and structural groups of CKs. Application of TDZ contributed to little or no increase in CK levels regardless of sucrose concentration. Analysis of expression profiles of organogenesis-related genes involved in auxin transport, CK response, shoot apical meristem formation and cell division revealed that higher sugar concentration significantly downregulated the analysed genes, particularly in T3. This continued on TDZ, but transZ induced an opposite effect with 9% sucrose in T4, increasing gene activity. Our results demonstrated that phytohormone metabolism might be triggered by sucrose signalling in kohlrabi DNSO.


Assuntos
Brassica/metabolismo , Genes de Plantas , Compostos de Fenilureia/farmacologia , Reguladores de Crescimento de Plantas/farmacologia , Sacarose/metabolismo , Tiadiazóis/farmacologia , Zeatina/farmacologia , Brassica/genética , Brassica/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Homeostase , Meristema/efeitos dos fármacos , Meristema/genética , Meristema/crescimento & desenvolvimento
10.
Neotrop Entomol ; 50(2): 298-302, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33683558

RESUMO

The diamondback moth (DBM), Plutella xylostella (L.) (Lep.: Plutellidae), is an important pest of broccoli (Brassica oleracea L. var. italica Plenck). Few studies have focused on the real DBM impact on broccoli yield. We performed greenhouse studies to assess the effect of DBM densities and infestation timing (at pre-heading, heading, or during the entire cycle) on broccoli head weight. Polynomial trend analysis revealed a downward linear response of head weight to DBM densities, indicating that broccoli is susceptible to DBM attack. As for the infestation timing, infestations during the pre-heading stage significantly impacted head weight, whereas the same did not occur for infestations during the heading stage. DBM density did not affect plant height or total leaves but was upward-related to plant defoliation, and head weight correlated negatively with plant defoliation. These findings indicate that pre-heading is the determining stage for head weight loss of plants under DBM attack. In order to prevent quantitative losses, efforts for DBM management should be focused on this particular stage.


Assuntos
Brassica , Herbivoria , Mariposas , Animais , Brassica/crescimento & desenvolvimento , Larva , Folhas de Planta
11.
Arch Microbiol ; 203(5): 2411-2418, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33661315

RESUMO

Endophytic fungi (EPF) colonize plant roots and enhance their growth. The relationship between host plant and EPF can be affected by several factors, such as growth media, host species, and fungal species. The objective of this study was to clarify the effect of nutrient concentration in growth media on the relationship between host plant and root EPF. Brassica campestris was grown in 1/100 Murashige and Skoog (MS), 1/10 MS, 1/100 MS and 1/10 nitrogen (high N), and 1/100 MS and 1/10 phosphorus (high P) media. B. campestris was inoculated with four root EPFs isolated from forest soils in Indonesia and harvested 28 days after transplant. Shoot dry weight (SDW) and colonization in roots were measured. All the isolates colonized roots of B. campestris. Two isolates increased the SDW of B. campestris grown on 1/100 MS media. The shoot growth response of B. campestris to EPF colonization on 1/100 MS was higher than that on 1/100 high N and 1/100 high P MS media. These results suggest that concentration of nitrogen and phosphorus in growth media determine the relationship between B. campestris and root EPF.


Assuntos
Brassica/crescimento & desenvolvimento , Endófitos/fisiologia , Fungos/fisiologia , Nitrogênio/metabolismo , Fósforo/metabolismo , Interações entre Hospedeiro e Microrganismos , Raízes de Plantas/microbiologia , Solo , Microbiologia do Solo
12.
Sci Rep ; 11(1): 1770, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33469090

RESUMO

Calcium (Ca) deficiency in cabbage plants induces oxidative damage, hampering growth and decreasing quality, however, it is hypothesized that silicon (Si) added to the nutrient solution may alleviate crop losses. Therefore, this study aims at evaluating whether silicon supplied in the nutrient solution reduces, in fact, the calcium deficiency effects on cabbage plants. In a greenhouse, cabbage plants were grown using nutrient solutions with Ca sufficiency and Ca deficiency (5 mM) without and with added silicon (2.5 mM), arranged as a 2 × 2 factorial in randomized blocks, with five replications. At 91 days after transplanting, the plants were harvested for biological evaluations. In the treatment without added Si, Ca deficiency promoted oxidative stress, low antioxidant content, decreased dry matter, and lower quality leaf. On the other hand, added Si attenuated Ca deficiency in cabbage by decreasing cell extravasation while increasing both ascorbic acid content and fresh and dry matter, providing firmer leaves due to diminished leaf water loss after harvesting. We highlighted the agronomic importance of Si added to the nutrient solution, especially in crops at risk of Ca deficiency.


Assuntos
Ácido Ascórbico/metabolismo , Brassica/crescimento & desenvolvimento , Brassica/metabolismo , Cálcio/deficiência , Silício/metabolismo , Ácido Ascórbico/análise , Estresse Oxidativo/fisiologia , Desenvolvimento Vegetal/fisiologia , Folhas de Planta/crescimento & desenvolvimento , Fenômenos Fisiológicos Vegetais/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
13.
Sensors (Basel) ; 21(2)2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33445510

RESUMO

The correct fertilization of vegetable crops is commonly determined on the basis of soil and plant costly destructive analyses, demanding more sustainable non-invasive optical detection. Here, we tested the ability of the combined transmittance/fluorescence leaf clip Dualex device for determining the nitrogen (N) status of cabbage plants. Fully developed leaves from plants grown under different N rates of 0; 100; 200; 300 kg N ha-1 in 2018 and 2019 were measured in the field by the Dualex sensor twice a year in July and October. The chlorophyll (Chl) and nitrogen (nitrogen balance index, NBI) indices and the flavonols (Flav) index of the sensor were positively and negatively correlated to leaf nitrogen, respectively. Merging the two-years data, the NBI versus leaf N correlation was less point dispersed in October than July (R2 = 0.76 and 0.64, respectively). NBI was also correlated to cabbage yield, better in July than October. Our results showed that the multiparametric Dualex device can be used as precision agriculture tool for the early prediction of plant N and cabbage yield with economic advantage for the growers and reduced environmental contamination due to nitrate leaching.


Assuntos
Brassica/química , Brassica/crescimento & desenvolvimento , Nitrogênio/análise , Folhas de Planta/química , Clorofila/análise , Desenho de Equipamento , Fertilizantes , Fluorescência , Polônia
14.
Bioelectrochemistry ; 138: 107727, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33429155

RESUMO

Several studies have demonstrated that electric treatment has a positive effect, respectively, on germination, root growth and post-harvest quality. Nevertheless, there is still a lack of research on the effect of electric treatment on growth characteristics and quality of whole plants. Here, we explored the effect of electric fields on two cultivars of kale (Brassica oleracea var. acephala). Three levels of electric current (10, 50, and 100 mA) were applied to the nutrient solution of hydroponically grown plants for three weeks. Kale plants subjected to the electric fields, particularly 50 mA, had higher fresh and dry weights than the control. The absence of an electric field in a Faraday cage caused a significant decrease in shoot and root growth compared with the natural electric field (control). Electrostimulation enhanced nutrient uptake by activating root hair formation and active ion transport. Plants grown under 50 mA contained 72% more calcium, 57% more total phenolic compounds, and had a 70% greater antioxidant capacity than the control. This work provides foundational information regarding the effects of electrical stimulus on plants, which could enable the development of innovative culture technologies to improve crop yields and quality.


Assuntos
Antioxidantes/metabolismo , Brassica/crescimento & desenvolvimento , Brassica/metabolismo , Minerais/metabolismo , Transporte Biológico , Estimulação Elétrica
15.
Molecules ; 26(2)2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33477705

RESUMO

Recently, there have been efforts to use ultraviolet-B radiation (UV-B) as a biotechnological tool in greenhouses. Leafy Brassica species are mainly considered for their ability to synthesize glucosinolates and are valued as baby salads. They also have a remarkable concentration of chemically diverse flavonoid glycosides. In this study, the effect of short-term UV-B radiation at the end of the production cycle was investigated without affecting plant growth. The aim was to verify which exposure and adaptation time was suitable and needs to be further investigated to use UV as a biotechnological tool in greenhouse production of Brassica species. It is possible to modify the flavonoid glycoside profile of leafy Brassica species by increasing compounds that appear to have potentially high antioxidant activity. Exemplarily, the present experiment shows that kaempferol glycosides may be preferred over quercetin glycosides in response to UV-B in Brassica rapa ssp. chinensis, for example, whereas other species appear to prefer quercetin glycosides over kaempferol glycosides, such as Brassica oleracea var. sabellica or Brassica carinata. However, the response to short-term UV-B treatment is species-specific and conclusions on exposure and adaptation time cannot be unified but must be drawn separately for each species.


Assuntos
Adaptação Fisiológica , Brassica/metabolismo , Flavonoides/metabolismo , Glicosídeos/metabolismo , Folhas de Planta/metabolismo , Raios Ultravioleta/efeitos adversos , Brassica/classificação , Brassica/crescimento & desenvolvimento , Brassica/efeitos da radiação , Flavonoides/análise , Flavonoides/efeitos da radiação , Glicosídeos/análise , Glicosídeos/efeitos da radiação , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/efeitos da radiação , Especificidade da Espécie , Fatores de Tempo
16.
J Sci Food Agric ; 101(4): 1629-1635, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32893880

RESUMO

BACKGROUND: Chlorophyll is the most abundant pigment on Earth, essential for the capture of light energy during photosynthesis. During senescence, chlorophyll degradation is highly regulated in order to diminish toxicity of the free chlorophyll molecule due to its photoactivity. The first step in the chlorophyll degradation pathway is the conversion of chlorophyll b to chlorophyll a by means of two consecutive reactions catalyzed by enzymes coded by NYC1 (NON-YELLOW COLORING 1), NOL (NYC1-LIKE) and HCAR. RESULTS: In this work, we studied the expression of NOL and HCAR genes during postharvest senescence of broccoli. We found that the expression of BoNOL increase during the first days of storage and then decrease. In the case of BoHCAR, its expression is maintained during the first days and then it also diminishes. Additionally, the effect of different postharvest treatments on the expression of these genes was also analyzed. It was observed that the expression of BoNOL is lower in the treatments performed with 1-methylcyclopropene (1-MCP), 6-benzylaminopurine (6-BAP) and modified atmospheres, while BoHCAR expression showed an increase in these same treatments, and a decrease in the treatment with ethylene. There were no variations in the expression of both genes in heat treatment, UV-C treatment and visible light treatment. CONCLUSIONS: These results suggest that both BoHCAR and BoNOL show a lower regulation of their expression than other genes involved in chlorophyll degradation during senescence. © 2020 Society of Chemical Industry.


Assuntos
Brassica/enzimologia , Brassica/genética , Proteínas de Plantas/genética , Brassica/crescimento & desenvolvimento , Brassica/metabolismo , Clorofila/metabolismo , Clorofila A/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo
17.
J Chem Ecol ; 47(1): 112-122, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33180275

RESUMO

Plants evolved in close contact with a myriad of microorganisms, some of which formed associations with their roots, benefitting from carbohydrates and other plant resources. In exchange, they evolved to influence important plant functions, e.g. defense against insect herbivores and other antagonists. Here, we test whether a fungus, Metarhizium brunneum, which is mostly known as an insect pathogen, can also associate with plant roots and contribute to above-ground plant defense. Cauliflower (Brassica oleracea var. botrytis) seeds were sown together with M. brunneum-inoculated rice grains, and the resulting plants subjected to leaf herbivory by the specialist Plutella xylostella. Activity of myrosinases, the enzymes activating glucosinolates, was measured before and after herbivory; larval consumption and plant weight at the end of experiments. Metarhizium brunneum clearly established in the plant roots, and after herbivory myrosinase activity was substantially higher in M. brunneum-treated plants than in controls; before herbivory, M. brunneum-treated and control plants did not differ. Leaf consumption was slightly lower in the M. brunneum-treated plants whereas total biomass and allocation to above- or below-ground parts was not affected by the Metarhizium treatment. Thus, M. brunneum associates with roots and primes the plant for a stronger or faster increase in myrosinase activity upon herbivory. Consistent with this, myrosinase function has been suggested to be rate-limiting for induction of the glucosinolate-myrosinase defense system. Our results show that M. brunneum, in addition to being an insect pathogen, can associate with plant roots and prime plant defense.


Assuntos
Brassica/enzimologia , Glicosídeo Hidrolases/metabolismo , Metarhizium/fisiologia , Mariposas/fisiologia , Defesa das Plantas contra Herbivoria , Raízes de Plantas/enzimologia , Animais , Brassica/crescimento & desenvolvimento , Brassica/microbiologia , Herbivoria , Larva/fisiologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia
18.
J Sci Food Agric ; 101(1): 44-53, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32949155

RESUMO

BACKGROUND: The main objective of this study was to evaluate physiological and quality changes of minimally processed broccoli sprouts illuminated during postharvest storage under blue, red and far-red LED lighting as compared to darkness or illumination with fluorescent light, as control treatments. RESULTS: Morphological and microbiological changes were determined during 15 days at 5 °C. In addition, total antioxidant activity and bioactive compound changes throughout the shelf life were also monitored. Results showed that far-red LED lighting increased hypocotyl and sprout length, decreased microbial growth and improved the total antioxidant and scavenging activities, compared to darkness and fluorescent lighting treatments. However, it did not stimulate the biosynthesis of phenolic acids. In contrast, blue LED light reduced by 50% the total antioxidant capacity of broccoli sprouts compared to far-red treatment, as well as morphological development. In addition, total scavenging activity was increased under far-red LED light compared with the other treatments by 12-10% (darkness and fluorescence) and 33-31% (blue and red LEDs). CONCLUSIONS: Our results suggest that minimally processed sprouts may benefit from LED lighting during shelf life in terms of quality, although further experiments should be conducted to optimize a proper exposure cycle and intensity aiming for use in the distribution chain. The results also open the way for further development towards the integration of this technology in the food distribution chain.


Assuntos
Brassica/química , Brassica/efeitos da radiação , Antioxidantes/química , Antioxidantes/metabolismo , Brassica/crescimento & desenvolvimento , Brassica/metabolismo , Cor , Luz , Fenóis/química , Fenóis/metabolismo , Extratos Vegetais/química , Extratos Vegetais/metabolismo
19.
Food Chem ; 334: 127520, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32693332

RESUMO

CaCl2, Ca2+ chelator (EGTA) and Ca2+ channel blocker (verapamil) were used to investigate mechanism of glucoraphanin metabolism in broccoli sprouts under ZnSO4 stress. CaCl2 treatment promoted sprout growth, reduced MDA (malonaldehyde) content and electrolyte leakage in sprouts under ZnSO4 stress. The highest MDA content and electrolyte leakage were obtained in ZnSO4 plus verapamil-treated sprouts. In addition, ZnSO4 plus CaCl2 treatment significantly enhanced glucoraphanin content and sulforaphane formation, while an opposite result was observed after ZnSO4 plus EGTA treatment; which were further supported by expression of glucoraphanin biosynthetic and hydrolytic genes as well as myrosinase (MYR) and epithiospecifier protein (ESP) activities. These results indicated that exogenous and endogenous calcium promoted glucoraphanin biosynthesis and the conversion rate of glucoraphanin into sulforaphane. Verapamil treatment also stimulated glucoraphanin biosynthesis, but exerted an adverse influence on sulforaphane formation from the hydrolysis of glucoraphanin because of much higher ESP expression and ESP activity than ZnSO4 treatment.


Assuntos
Brassica/efeitos dos fármacos , Cloreto de Cálcio/farmacologia , Glucosinolatos/metabolismo , Imidoésteres/metabolismo , Sulfato de Zinco/farmacologia , Brassica/crescimento & desenvolvimento , Brassica/metabolismo , Ácido Egtázico/farmacologia , Glicosídeo Hidrolases/metabolismo , Hidrólise , Isotiocianatos/metabolismo , Malondialdeído/metabolismo , Proteínas de Plantas/metabolismo , Plântula/efeitos dos fármacos , Plântula/metabolismo , Estresse Fisiológico
20.
Molecules ; 25(20)2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33086545

RESUMO

Selenium (Se) supplement was combined with different LED light qualities to investigate mutual effects on the growth, nutritional quality, contents of glucosinolates and mineral elements in broccoli sprouts. There were five treatments: CK:1R1B1G, 1R1B1G+Se (100 µmol L-1 Na2SeO3), 1R1B+Se, 1R2B+Se, 2R1B+Se, 60 µmol m-2 s-1 PPFD, 12 h/12 h (light/dark). Sprouts under a combination of selenium and LED light quality treatment exhibited no remarkable change fresh weight, but had a shorter hypocotyl length, lower moisture content and heavier dry weight, especially with 1R2B+Se treatment. The contents of carotenoid, soluble protein, soluble sugar, vitamin C, total flavonoids, total polyphenol and contents of total glucosinolates and organic Se were dramatically improved through the combination of Se and LED light quality. Moreover, heat map and principal component analysis showed that broccoli sprouts under 1R2B+Se treatment had higher nutritional quality and health-promoting compound contents than other treatments. This suggests that the Se supplement under suitable LED lights might be beneficial to selenium-biofortified broccoli sprout production.


Assuntos
Brassica/crescimento & desenvolvimento , Proteínas/metabolismo , Plântula/crescimento & desenvolvimento , Selênio/farmacologia , Ácido Ascórbico/biossíntese , Brassica/efeitos dos fármacos , Brassica/metabolismo , Brassica/efeitos da radiação , Carotenoides/metabolismo , Flavonoides/biossíntese , Glucosinolatos/biossíntese , Humanos , Luz , Polifenóis/biossíntese , Plântula/efeitos dos fármacos , Plântula/efeitos da radiação , Selênio/metabolismo , Açúcares/metabolismo
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