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1.
J Photochem Photobiol B ; 203: 111656, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31676121

RESUMO

Strawberries are one of the most common and important fruits in the world, widely investigated for their nutritional and nutraceutical properties. However, after the emergence of several outbreaks of foodborne diseases some concerns regarding the microbiological safety of fresh strawberries have increased in recent years. In this paper new insights, based on application of ZnO nanoparticles (NPs) as alternative to chemical fungicides in the fields for preharvest preservation of strawberries are presented. Antifungal activity of ZnO NPs was tested on main strawberry plant pathogen Botrytis cinerea. Obtained data indicated that used ZnO NPs (5 × 10-3 M) in the dark just insignificantly (12%) inhibited the radial growth of B. cinerea. But photoactivated ZnO NPs (5 × 10-3 M, 405 nm, 34 J/cm2) inhibited the growth of B. cinera by 80%. Real-time field experiments revelead, that spraying of ZnO NPs in the strawberry field in sunny day reduced Botrytis incidences by 43%, enhanced the crop production by 28.5% and stoped the spoilage of harvested fruits during storage by 8 days, if compare with control. No harm to crowns and leaves of strawberry plant have been found, however this treatment increased the growth of inflorescence (37.5%) and reduced the growth of runners (32.8%). For comparison, spraying of conventionqal chemical fungicide fenhexamid (FEN) reduced Botrytis incidences in the same level as ZnO NPs, increased the harvest by 21.9% and delayed the spoilage of fruits by 8 days. The presented results look highly promising, since ZnO NPs in the presence of sunlight, activated by UV and visible light can protect strawberry fruits from Botrytis infection more effectively than conventional fungicide fenhexamid. This treatment significantly increased crop production and reduced spoilage of strawberries. It looks like ZnO NPs have great potential in the future to replace chemical fungicides.


Assuntos
Fragaria/crescimento & desenvolvimento , Nanopartículas Metálicas/química , Luz Solar , Óxido de Zinco/química , Amidas/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Botrytis/efeitos dos fármacos , Botrytis/efeitos da radiação , Catálise , Proteção de Cultivos , Nanopartículas Metálicas/toxicidade , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle
2.
Ecotoxicol Environ Saf ; 188: 109842, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31707322

RESUMO

Twelve commercial pesticide formulations containing sixteen active ingredients were applied on greenhouse strawberries at recommended and double doses. The dynamics and dietary risk analysis were investigated. A modified QuEChERS method based on the use of multi-walled carbon nanotubes (MWCNTs) as adsorbent followed by LC-MS/MS and GC-MS/MS detection was utilized for sample analysis. The half-lives of studied pesticides were 4.6-12.6 days and 3.8-15.8 days from two application doses. Dietary levels from the residue concentrations of the individual pesticides at harvest was contrasted with the acceptable daily intake (ADI) and acute reference dose (ARfD). The dietary risk assessment adopt the risk quotient (RQ) for chronic risk and risk probability (RP) for long-term dietary intake risk, respectively. The dietary risk induced by the studied pesticide residues in strawberry was acceptable for consumers except the pesticide fumigants. The pesticide residues at different pre-harvest intervals (PHIs) under greenhouse conditions were compared with the established maximum residue limits (MRLs). To reduce the residue levels and potential safety risk, a longer PHI or reduced application rates should be conducted.


Assuntos
Contaminação de Alimentos/análise , Fragaria/química , Frutas/química , Resíduos de Praguicidas/análise , Cromatografia Líquida , Fragaria/crescimento & desenvolvimento , Frutas/crescimento & desenvolvimento , Nanotubos de Carbono/química , Nível de Efeito Adverso não Observado , Resíduos de Praguicidas/toxicidade , Medição de Risco , Espectrometria de Massas em Tandem
3.
Food Chem ; 309: 125662, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31704072

RESUMO

Strawberry cultivar "San Andreas" was grown under ambient (400 ppm CO2, 25 °C) and elevated (950 ppm CO2, 30 °C) growth conditions. The strawberries were subjected to in vitro gastrointestinal digestion and colonic fermentation to examine the accessibility of polyphenols, vitamin C and folates in fresh and frozen fruits using HPLC-UV analyses. Results revealed that elevated CO2 and higher temperature enhanced the amounts of accessible bioactive compounds in strawberries. Bioaccessibility of pelargonidin-3-glucoside increased from 67% to 88% in strawberries grown under elevated growth. Fresh strawberries grown under ambient growth contained 93.09 ±â€¯6.2 µg/100 g folates and 18.55 ±â€¯0.5 mg/100 g vitamin C as bioaccessible fractions under fed state while, elevated growth enhanced soluble folates and vitamin C up to 188.63 ±â€¯7.5 µg/100 g and 30.48 ±â€¯0.3 mg/100 g, respectively. Fresh strawberries contained higher amounts of accessible micronutrients than frozen strawberries, while increased bile contents in intestinal fluid (fed state) facilitated the release of bioactive compounds to gastrointestinal fluid.


Assuntos
Dióxido de Carbono/química , Cromatografia Líquida de Alta Pressão/métodos , Fragaria/metabolismo , Micronutrientes/análise , Antocianinas/metabolismo , Ácido Ascórbico/análise , Dióxido de Carbono/metabolismo , Ácido Fólico/análise , Fragaria/crescimento & desenvolvimento , Congelamento , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Polifenóis/análise , Temperatura
4.
BMC Plant Biol ; 19(1): 586, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31881835

RESUMO

BACKGROUND: In soft fruits, the differential expression of many genes during development and ripening is responsible for changing their organoleptic properties. In strawberry fruit, although some genes involved in the metabolic regulation of the ripening process have been functionally characterized, some of the most studied genes correspond to transcription factors. High throughput transcriptomics analyses performed in strawberry red receptacle (Fragaria x ananassa) allowed us to identify a ripening-related gene that codes an atypical HLH (FaPRE1) with high sequence homology with the PACLOBUTRAZOL RESISTANCE (PRE) genes. PRE genes are atypical bHLH proteins characterized by the lack of a DNA-binding domain and whose function has been linked to the regulation of cell elongation processes. RESULTS: FaPRE1 sequence analysis indicates that this gene belongs to the subfamily of atypical bHLHs that also includes ILI-1 from rice, SlPRE2 from tomato and AtPRE1 from Arabidopsis, which are involved in transcriptional regulatory processes as repressors, through the blockage by heterodimerization of bHLH transcription factors. FaPRE1 presented a transcriptional model characteristic of a ripening-related gene with receptacle-specific expression, being repressed by auxins and activated by abscisic acid (ABA). However, its expression was not affected by gibberellic acid (GA3). On the other hand, the transitory silencing of FaPRE1 transcription by agroinfiltration in receptacle produced the down-regulation of a group of genes related to the ripening process while inducing the transcription of genes involved in receptacle growth and development. CONCLUSIONS: In summary, this work presents for the first time experimental data that support an important novel function for the atypical HLH FaPRE1 during the strawberry fruit ripening. We hypothesize that FaPRE1 modulates antagonistically the transcription of genes related to both receptacle growth and ripening. Thus, FaPRE1 would repress the expression of receptacle growth promoting genes in the ripened receptacle, while it would activate the expression of those genes related to the receptacle ripening process.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/fisiologia , Fragaria/fisiologia , Proteínas de Plantas/fisiologia , Fatores de Transcrição/fisiologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fragaria/efeitos dos fármacos , Fragaria/genética , Fragaria/crescimento & desenvolvimento , Frutas/genética , Frutas/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Inativação Gênica , Proteínas Nucleares/genética , Proteínas Nucleares/fisiologia , Desenvolvimento Vegetal/genética , Reguladores de Crescimento de Planta/fisiologia , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Triazóis/farmacologia
5.
BMC Plant Biol ; 19(1): 505, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31744478

RESUMO

BACKGROUND: Ramet propagation in strawberry (Fragaria × ananassa) is the most effective way in production. However, the lack of systematically phenotypic observations and high-throughput methods limits our ability to analyze the key factors regulating the heterogeneity in strawberry stolon buds. RESULTS: From observation, we found that the axillary bud located in the first node quickly stepped into dormancy (DSB), after several bract and leaf buds were differentiated. The stolon apical meristem (SAM) degenerated as the new ramet leaf buds (RLB), and the new active axillary stolon buds (ASB) differentiated continually after the differentiation of the first leaf. Using the tandem mass tags (TMT) labeling method, a total of 7271 strawberry proteins were identified. Between ASB and DSB, the spliceosome DEPs, such as Ser/Arg-rich (SR) and heterogeneous nuclear ribonucleoprotein particle (hnRNP), showed the highest enrichment and high PPI connectivity. This indicated that the differences in DEPs (e.g., SF-3A and PK) at the transcriptional level may be causing the differences between the physiological statuses of ASB and DSB. As expected, the photosynthetic pre-form RLB mainly differentiated from ASB and DSB judging by the DEP enrichment of photosynthesis. However, there are still other specialized features of DEPs between RLB and DSB and between ASB and DSB. The DEPs relative to DNA duplication [e.g., minichromosome maintenance protein (MCM 2, 3, 4, 7)], provide a strong hint of functional gene duplication leading the bud heterogeneity between RLB and DSB. In addition, the top fold change DEP of LSH 10-like might be involved in the degeneration of SAM into RLBs, based on its significant function in modulating the plant shoot initiation. As for RLB/ASB, the phenylpropanoid biosynthesis pathway probably regulates the ramet axillary bud specialization, and further promotes the differentiation of xylem when ASB develops into a new stolon [e.g., cinnamyl alcohol dehydrogenase 1 (CAD1) and phenylalanine ammonia-lyase 1 (PAL1)]. CONCLUSIONS: By using phenotypic observation combined with proteomic networks with different types of strawberry stolon buds, the definite dormancy phase of DSB was identified, and the biological pathways and gene networks that might be responsible for heterogeneity among different stolon buds in strawberry were also revealed.


Assuntos
Fragaria/fisiologia , Proteínas de Plantas/metabolismo , Proteômica , Cromatografia Líquida , Biologia Computacional , Fragaria/genética , Fragaria/crescimento & desenvolvimento , Meristema/genética , Meristema/crescimento & desenvolvimento , Meristema/fisiologia , Fenótipo , Dormência de Plantas , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/fisiologia , Mapas de Interação de Proteínas , Espectrometria de Massas em Tandem
6.
BMC Plant Biol ; 19(1): 386, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31488054

RESUMO

BACKGROUND: Consumers purchase fresh strawberries all year long. Extending the fruiting season for new strawberry cultivars is a common breeding goal. Understanding the inheritance of repeat fruiting is key to improving breeding efficiency. Several independent research groups using multiple genotypes and analytic approaches have all identified a single genomic region in strawberry associated with repeat fruiting. Markers mapped to this region were used to evaluate breeding parents from the United States Department of Agriculture - Agricultural Research Service (USDA-ARS) strawberry breeding program at Beltsville, Maryland. RESULTS: Markers mapped to repeat fruiting identified once-fruiting genotypes but not repeat-fruiting genotypes. Eleven of twenty-three breeding parents with repeat-fruiting marker profiles were actually once fruiting, indicating at least one additional locus acting epistatically to suppress repeat fruiting. Family segregation ratios could not be predicted reliably by the combined use of parental phenotypes and marker profiles, when using a single-gene model. Expected segregation ratios were calculated for all phenotypic and marker-profile combinations possible from the mapped locus combined with a hypothetical dominant or recessive suppressor locus. Segregation ratios specific to an epistatic suppressor acting on the mapped locus were observed in four families. The segregation ratios for two families were best explained by a dominant suppressor acting on the mapped locus, and, for the other two, by a recessive suppressor. Not all of the observed ratios could be explained by one model or the other, and when multiple families with a common parent were compared, there was no predicted genotype for the common parent that would lead to all of the observed segregation ratios. CONCLUSIONS: Considering all lines of evidence in this study and others, repeat-fruiting in commercial strawberry is controlled primarily by a dominant allele at a single locus, previously mapped by multiple groups. At least two additional genes, one dominant and one recessive, exist that act epistatically to suppress repeat fruiting. Environmental effects and/or incomplete penetrance likely affect phenotype through the suppressor loci, rather than the primary mapped locus. One of the dominant suppressors acts only in the first year, the year the plant is germinated from seed, and not after the plant has experienced a winter.


Assuntos
Epistasia Genética , Fragaria/genética , Frutas/crescimento & desenvolvimento , Melhoramento Vegetal , Fragaria/crescimento & desenvolvimento , Frutas/genética , Genótipo , Fenótipo
7.
J Sci Food Agric ; 99(15): 6973-6980, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31414485

RESUMO

BACKGROUND: Plants activate defense mechanisms to cope with adverse environmental conditions, leading to the accumulation and / or depletion of general and specialized metabolites. In this study, a multiplatform untargeted metabolomics strategy was employed to evaluate metabolic changes in strawberry fruit of cv. Camarosa grown under osmotic stress conditions. Liquid chromatography-mass spectrometry (LC-MS/MS) and gas chromatography-mass spectrometry (GC-MS) data from strawberries grown under two water-deficit conditions, irrigated at 95% crop evapotranspiration (ETc) and 85% ETc, and one excess salt condition with a 80 mmol L-1 NaCl solution, were analyzed to determine treatment effects on fruit metabolism. RESULTS: Multivariate principal component analysis, orthogonal projections to latent structures - discriminant analysis (OPLS-DA), and univariate statistical analyses were applied to the data set. While multivariate analyses showed group separation by treatment, T-tests and fold change revealed 12 metabolites differentially accumulated in strawberries from different treatments - among them phenolic compounds, glycerophospholipids, phytosterols, carbohydrates, and an aromatic amino acid. CONCLUSION: Untargeted metabolomic analysis allowed for the annotation of compounds differentially accumulated in strawberry fruit from plants grown under osmotic stress and non-stressed plants. The metabolic disturbance in plants under stress involved metabolites associated with the inhibition of reactive oxygen species and cell-wall and membrane lipid biosynthesis, which might serve as osmotic stress biomarkers. © 2019 Society of Chemical Industry.


Assuntos
Fragaria/química , Frutas/metabolismo , Cromatografia Líquida , Fragaria/crescimento & desenvolvimento , Fragaria/metabolismo , Frutas/química , Frutas/crescimento & desenvolvimento , Cromatografia Gasosa-Espectrometria de Massas , Metabolômica , Pressão Osmótica , Cloreto de Sódio/análise , Cloreto de Sódio/metabolismo , Espectrometria de Massas em Tandem , Água/análise , Água/metabolismo
8.
Food Chem ; 299: 125110, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31284244

RESUMO

This study was undertaken in order to estimate the effect of in vitro propagation on antioxidant activity in strawberry. Results of this research exhibited differences between conventionally and in vitro propagated plants in respect of all traits analyzed. In spite of the decrease in range and mean content of vitamin C and polyphenols as well as antioxidant activity, the genetic gain expressed as percent of mean was higher in microplants regarding phenolics, flavonoids and antioxidant activity in contrast to conventional plants (22.39-20.83, 21.79-15.61, 9.52-3.39; resp.). Correlation and path coefficients showed changes of antioxidants inter-relations between micropropagated and conventional plants. Phenolics and vitamin C correlated positively with antioxidant activity in all genotypes. The highest positive direct effect on antioxidant activity was observed via vitamin C in microplants (0.705), while in conventional plants via phenolics (0.834). Flavonoids affected directly and positively antioxidant activity in microplants (0.103) and negatively in conventional plants (-0.143).


Assuntos
Antioxidantes/metabolismo , Flavonoides/metabolismo , Fragaria/crescimento & desenvolvimento , Fragaria/genética , Ácido Ascórbico/genética , Ácido Ascórbico/metabolismo , Flavonoides/genética , Fragaria/metabolismo , Genótipo , Fenóis/metabolismo , Polifenóis/genética , Polifenóis/metabolismo
9.
Mycorrhiza ; 29(5): 489-501, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31264099

RESUMO

Due to the impoverishment of agricultural and horticultural soils and replant diseases, there is a need to use bioproducts and beneficial microorganisms in order to improve the quality of soils and growth substrates. For this reason, research was undertaken to assess the impact of arbuscular mycorrhizal fungi and rhizosphere bacteria on changes in soil microbiology, the degree of colonization of plant roots by mycorrhizal fungi, selected physiological parameters, and fruit quality and yield of the strawberry cultivar "Rumba." The plants were inoculated with the mycorrhizal preparation Mykoflor (Rhizophagus irregularis, Funneliformis mosseae, Claroideoglomus etunicatum), MYC 800 (Rhizophagus intraradices), and the bacterial preparation Rhizocell C (Bacillus amyloliquefaciens IT45). The applied preparations increased the total number of bacteria and fungi in the soil and mycorrhizal frequency in the roots of the strawberry plants. They increased the chlorophyll "a" and total chlorophyll concentrations in the leaves as well as the rate of transpiration and CO2 concentration in the intercellular spaces in the leaves. The plants treated with Rhizocell C and MYC 800 exhibited a higher CO2 assimilation rate than control plants. The biopreparations increased chlorophyll fluorescence parameters such as maximum fluorescence (FM) and the maximum potential photochemical reaction efficiency in PS II (FV/FM). The influence of the species of rhizosphere bacteria and mycorrhizal fungi used in the experiment on the physiological traits of strawberry plants contributed, especially in the second year of the study, to increase the yield and mean weight of strawberry fruit.


Assuntos
Fenômenos Fisiológicos Bacterianos , Fragaria/fisiologia , Micorrizas/fisiologia , Rizosfera , Microbiologia do Solo , Fragaria/crescimento & desenvolvimento , Fragaria/microbiologia , Microbiota , Raízes de Plantas/microbiologia
10.
J Plant Physiol ; 239: 52-60, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31185317

RESUMO

The contents of eight phytohormones and the expression levels of genes encoding enzymes related to abscisic acid (ABA) biosynthesis and deactivation/degradation and transcription factors (TFs) related to fruit ripening were studied in the non-climacteric strawberry fruit (Fragaria × ananassa Duch., cv. 'Seolhyang') at six developmental stages. The hormones tested were ABA, indole-3-acetic acid (IAA), gibberellic acid 4 (GA4), jasmonic acid (JA), methyljasmonate (MJ), jasmonoyl isoleucine (JA-Ile), salicylic acid (SA), and ethylene (ET). The developmental and ripening stages studied were small green (S1, 11 days post-anthesis, DPA), green (S2, 20 DPA), breaker (S3, 24 DPA), pink (S4, 27 DPA), red (S5, 31 DPA), and fully red (S6, 40 DPA). IAA and GA4 contents were highest at S1 and gradually decreased after this stage. ABA content was low at S1-S3 and then increased rapidly until peaking at S6. By contrast, MJ content showed no significant changes over time, while SA content gradually increased. JA, JA-Ile, and ET contents were either insufficient for quantification or undetectable. Expression of the ABA biosynthesis genes FaNCED1 and FaABA2 increased during fruit ripening, whereas expression of the ABA deactivation/degradation genes FaUGT75C1 and FaCYP707A1 was high early in development, when ABA content was low, and then decreased. Among four ripening-related TF genes, FaMYB1, FaMYB5, FaMYB10, and FaASR, only the expression of FaMYB10 seemed to be closely related to strawberry fruit ripening. Our study supports the idea that ABA and FaMYB10 appear to be the key hormone and TF regulating strawberry ripening.


Assuntos
Ácido Abscísico/genética , Fragaria/genética , Regulação da Expressão Gênica de Plantas , Reguladores de Crescimento de Planta/metabolismo , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Ácido Abscísico/metabolismo , Fragaria/crescimento & desenvolvimento , Frutas/genética , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo
11.
Microbiol Res ; 223-225: 120-128, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31178044

RESUMO

Plant growth-promoting bacteria have been highlighted by their potential for application in plant production, allowing the reduction of the use of fertilizers and pesticides, which is due to the ability to stimulate the growth of plants by nitrogen-fixation and production of phytohormones, such as indole-3-acetic acid (IAA). The objective of this study was to verify the potential of plant growth promotion of 25 wild isolates from the Agricultural Microbiology Culture Collection of the Federal University of Lavras (CCMA-UFLA) through the evaluation of the biological nitrogen-fixation capacity and the production of IAA. In addition, the growth of three selected strains inoculated on roots of strawberry seedlings in greenhouse conditions was evaluated. The experiment was conducted in a completely randomized design (CRD), with an 8 × 2 factorial schemes involving eight combinations of bacteria: alone, in pairs and threes, plus the control without inoculation. Two fertilizer levels were used (0% and 50% of nitrogen), totaling 16 treatments with eight replicates each. After 75 days, variables such as root length, root dry weight, aerial part length, aerial part dry weight, leaf number, total dry mass and ultrastructural analysis of the inoculated and uninoculated roots, were evaluated. The results showed that the strawberry crop responded positively to inoculation with the three bacteria combined Azospirillum brasilense (Ab-V5) + Burkholderia cepacia (CCMA 0056) + Enterobacter cloacae (CCMA 1285) compared to the uninoculated controls. More expressive responses in terms of plant growth were observed in relation to the combined inoculation of the three bacterial strains plus fertilizer application with 50% of nitrogen.


Assuntos
Fenômenos Fisiológicos Bacterianos , Fragaria/crescimento & desenvolvimento , Fragaria/microbiologia , Fixação de Nitrogênio , Desenvolvimento Vegetal , Azospirillum brasilense/fisiologia , Bactérias/classificação , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Bactérias/metabolismo , Biomassa , Burkholderia cepacia/fisiologia , Enterobacter cloacae , Ácidos Indolacéticos/metabolismo , Nitrogênio , Reguladores de Crescimento de Planta/metabolismo , Folhas de Planta/microbiologia , Raízes de Plantas/microbiologia , Plântula
12.
J Sci Food Agric ; 99(12): 5341-5349, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31058322

RESUMO

BACKGROUND: The strawberry (Fragaria × ananassa Duch.) is, among small fruits, the most cultivated and commercialized in Portugal. Recent studies have evidenced the positive effect of plant growth-promoting bacteria (PGPB) inoculation on strawberry production and, at the same time, provided an alternative strategy to reduce the use of fertilizers. In this study the effects of root inoculation with three PGPB strains (Pedobacter sp. CC1, Bacillus safensis B106 and Bacillus subtilis B167A) on the physiology, growth, fruit production and quality of strawberry cv. Camarosa are presented. RESULTS: PGPB inoculation significantly accelerated crop maturation, with inoculated plants fruiting about 2 weeks earlier than non-inoculated plants. Inoculated plants with Pedobacter sp. CC1 and Bacillus safensis B106 influenced the gas exchange parameters of strawberry plants. The contents of total phenolics and flavonoids in strawberry leaves were found to be greater with Pedobacter sp. CC1, when compared with non-inoculated plants. Furthermore, plants inoculated with the same bacterial strain showed enhancement in the dimensions of fruits, especially fruit length, and shape as well as in the total soluble solids content (°Brix). CONCLUSIONS: The results showed that the PGPB Pedobacter sp. CC1 improved performance of strawberry plants, suggesting that it could be a potential biofertilizer for strawberry plant nutrition. © 2019 Society of Chemical Industry.


Assuntos
Inoculantes Agrícolas/crescimento & desenvolvimento , Bacillus/fisiologia , Fragaria/crescimento & desenvolvimento , Fragaria/microbiologia , Frutas/química , Pedobacter/fisiologia , Fertilizantes/análise , Flavonoides/análise , Flavonoides/metabolismo , Fragaria/química , Fragaria/metabolismo , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Fenóis/análise , Fenóis/metabolismo , Portugal
13.
J Agric Food Chem ; 67(24): 6708-6715, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31140799

RESUMO

This is the first systemic assessment of the stereoselectivity of etoxazole enantiomers. Etoxazole's stereoselective bioactivity was assessed against target organisms ( Tetranychus urticae eggs and Tetranychus cinnabarinus eggs), and its acute toxicity was assessed toward nontarget aquatic organisms ( Daphnia magna and Danio rerio). Additionally, stereoselective elimination was investigated in three species of fruits (grape and strawberry grown in a greenhouse and apple grown in an open field) and in field soil. The ovicidal activity of (+)-( S)-etoxazole against Tetranychus urticae and Tetranychus cinnabarinus eggs was about 16 and 24 times higher, respectively, than that of (-)-( R)-etoxazole. Inconsistent order of etoxazole isomer toxicity was found toward different aquatic organisms: (+)-( S)-etoxazole showed nearly 8.7 times higher acute toxicity than (-)-( R)-etoxazole toward Daphnia magna, whereas (-)-( R)-etoxazole was ∼4.5 times more toxic to Danio rerio than (+)-( S)-etoxazole. Stereoselective degradation of etoxazole enantiomers showed significant variation in various fruits and field soil. The (+)-( S)-etoxazole was preferentially dissipated in grape and strawberry fruits grown under greenhouse condition, whereas (-)-( R)-etoxazole degraded faster than its antipode in apple fruits and soils under open-field condition. Overall, the stereoselectivity of etoxazole enantiomers should be fully considered in comprehensive environmental health risk in future work.


Assuntos
Acaricidas/química , Acaricidas/toxicidade , Frutas/química , Oxazóis/química , Oxazóis/toxicidade , Poluentes do Solo/química , Poluentes do Solo/toxicidade , Animais , Fragaria/química , Fragaria/crescimento & desenvolvimento , Frutas/crescimento & desenvolvimento , Malus/química , Malus/crescimento & desenvolvimento , Solo/química , Estereoisomerismo , Tetranychidae/efeitos dos fármacos , Vitis/química , Vitis/crescimento & desenvolvimento
14.
Sci Total Environ ; 675: 615-622, 2019 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-31035200

RESUMO

Chloropicrin (Pic) and biofumigation are both considered effective chemical and non-chemical alternatives to methyl bromide, respectively, for controlling crop-limiting soil-borne pests and diseases. In this study, we evaluated the effects of Pic alone and 'chloropicrin alternated with biofumigation' (CAB) on the soil's physico-chemical properties and strawberry yield, as well as their effects on soil bacterial and fungal communities. The contents of NO3--N, available phosphorus and potassium, and electrical conductivity were all significantly increased when CAB was used. In addition, CAB also significantly increased the strawberry marketable yield. High-throughput gene sequencing showed the species abundance of some soil bacteria and fungi was significantly increased such as the phyla Proteobacteria, Bacteroidetes, Actinobacteria and Ascomycota when CAB was used. However, CAB decreased the relative abundance of the phyla Firmicutes, Chloroflexi, Gemmatimonadete and Zygomycota. These results indicated that CAB could improve the physico-chemical properties of soil for strawberry production, increase the genetic diversity of microbes in the soil and enhance marketable fruit yield.


Assuntos
Agricultura/métodos , Produtos Agrícolas/crescimento & desenvolvimento , Hidrocarbonetos Clorados , Microbiologia do Solo , Ascomicetos/crescimento & desenvolvimento , Bactérias/crescimento & desenvolvimento , Firmicutes/crescimento & desenvolvimento , Fragaria/crescimento & desenvolvimento
15.
Exp Appl Acarol ; 77(3): 359-373, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30919170

RESUMO

Enhancing the performance of predatory mites is often regarded as the best biological control approach towards the spider mite Tetranychus urticae, the main pest of strawberry plantations. Optimizing the colonization of plantations by predators from adjacent areas such as field margins is seen as an important component of conservation biocontrol. We have investigated the factors contributing to enhancing the numbers of predatory mites (Acari: Phytoseidae), such as management of the field margins, vegetation composition and the effect of the presence of woody species. We also tested the penetration of the phytoseiids from the field margins into the crop. In a study carried out in 14 open-field extensively managed strawberry plantations in Poland we found phytoseiids to be abundant in field margins; 14 taxa were discovered. However, only two species Amblyseius andersoni and Euseius finlandicus dispersed a modest distance into the crop. We found that the diversity and densities of the predatory mites were enhanced somewhat by the management type of the field margins; especially the spontaneous vegetation favoured the presence of phytoseiids. However, despite the predatory mites being rather retained in the field margins also significant reduction in numbers of their prey T. urticae was recorded over the course of the year. The low penetration of predatory mites into the main part of the field, indicates that conservation biological control measures in the field margin might not be sufficient on their own to enhance the impact of predatory mites within the main part of the fields.


Assuntos
Proteção de Cultivos/métodos , Fragaria , Ácaros/fisiologia , Controle Biológico de Vetores/métodos , Comportamento Predatório , Animais , Fragaria/crescimento & desenvolvimento , Polônia , Tetranychidae/fisiologia , Controle de Ácaros e Carrapatos/métodos
16.
J Sci Food Agric ; 99(10): 4659-4669, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30906993

RESUMO

BACKGROUND: The strawberry cultivars 'Albion' and 'San Andreas' ('SA') were grown under various combinations of day temperature (25 and 30 °C) and carbon dioxide [CO2 ] (400, 650 and 950 µmol mol-1 ) conditions. The influence of different growth combinations on the polyphenol, flavonoid, anthocyanin, antioxidant, and individual phenolic compound content of fresh strawberry fruits was studied. The content of individual phenolic compounds of fresh strawberry fruits was quantified using high-performance liquid chromatography - ultraviolet (HPLC-UV). RESULTS: Elevated [CO2 ] and higher temperature caused significant increases in total polyphenol, flavonoid, anthocyanin and antioxidants in both strawberry cultivars when compared with plants grown under ambient conditions. Results of HPLC-UV analysis also revealed that individual phenolic compounds of fruits were also increased with increasing [CO2 ] and temperature. However, the responses were significantly altered by the interaction of elevated [CO2 ] and higher temperature. The individual and interaction effects of [CO2 ] and temperature were also significantly cultivar dependent. The largest amounts of flavonoid (482 ± 68 mg kg-1 FW) and antioxidant (19.0 ± 2.1 µmol g-1 FW) were detected in 'Albion' grown at 30 °C and under 950 µmol mol-1 , and total polyphenol (3350 ± 104 mg GAE kg-1 FW) and anthocyanin (332 ± 16 mg kg-1 FW) in 'San Andreas' grown at 25 °C and 950 µmol mol-1 . CONCLUSION: Strawberry fruit was rich with polyphenols and antioxidants when grown under elevated [CO2 ] and higher temperature. There were also interactions between [CO2 ] and temperature affecting the fruits' content. An increase in the polyphenol and antioxidant content in strawberry fruits would be highly beneficial to human health. © 2019 Society of Chemical Industry.


Assuntos
Dióxido de Carbono/farmacologia , Fragaria/efeitos dos fármacos , Frutas/química , Polifenóis/química , Antioxidantes/química , Dióxido de Carbono/análise , Cromatografia Líquida de Alta Pressão , Ecossistema , Fragaria/química , Fragaria/crescimento & desenvolvimento , Frutas/efeitos dos fármacos , Frutas/crescimento & desenvolvimento , Temperatura
17.
Plant Sci ; 281: 9-18, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30824065

RESUMO

Arabinogalactan proteins as cell wall structural proteins are involved in fundamental processes during plant development and growth. The aim of this study was to evaluate AGP function in the distribution of pectin, cellulose and callose along Fragaria x ananassa pollen tube and to associate the cell wall structure with local mechanical properties. We used Yariv reagent which interacts with AGPs and allows the observation of the assembly of cell walls without AGPs performing their function. Cytochemical, immunofluorescence labelling and atomic force microscope have been used to characterize the changes in cell wall structure and stiffness. It was shown that disordering of the structure of AGP present in cell walls affects the localization of cellulose, pectins and the secretion of callose. Changes in cell wall assembly are relevant to pollen tube mechanical properties. The stiffness gradient lengthwise through the axis of the pollen tube has demonstrated a significantly higher Young's modulus of the shank region than the growth zone. It has been revealed that the apex of the pollen tube cultured in the presence of Yariv reagent is stiffer (1.68 MPa) than the corresponding region of the pollen tube grown under control conditions (0.13-0.27 MPa). AGP affects the structure of the cell wall by changing the distribution of other components and the modification of their localization, and hence it plays a significant role in the mechanical properties of the cell wall.


Assuntos
Parede Celular/metabolismo , Fragaria/metabolismo , Tubo Polínico/metabolismo , Celulose/metabolismo , Fragaria/crescimento & desenvolvimento , Glucanos/metabolismo , Mucoproteínas/metabolismo , Pectinas/metabolismo , Proteínas de Plantas/metabolismo , Tubo Polínico/crescimento & desenvolvimento
18.
Sci Total Environ ; 664: 249-261, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-30743119

RESUMO

In this study, the environmental impact of strawberry production in Italy and Switzerland was evaluated using the Life Cycle Assessment (LCA) approach. The main differences between the two countries are the cultivation practices: crop cycle duration (1 year in Switzerland and 2 or 3 years in Italy), soil management and cultivation in open and protected fields. For all the environmental impact categories evaluated with LCA, strawberry production in Switzerland shows higher impacts respect to the Italian production. The impact reduction related to the Italian production in open fields without soil sterilisation ranges from 96% (for photochemical oxidant formation) to 35% (for freshwater eutrophication). For Swiss production, soil sterilisation is by far the main environmental hotspot for all the evaluated environmental effects except for toxicity-related impact categories and for resources consumption (i.e. manufacturing, maintenance and disposal of tunnel). Conversely, the main hotspot in Italy differs depending on the considered categories. Moreover, the 3-years cycle duration has a higher impact respect to the 2-years one because of the low yield in the third year that worsens the outcomes. Finally, sensitivity and uncertainty analysis were performed. The environmental results are deeply affected by yield variation and only slightly by changes in the life span of the tunnels while the uncertainty related to the selection of the data source, the model imprecision, and the variability of data does not affect significantly the results, except for the toxicity-related impact categories.


Assuntos
Agricultura/métodos , Monitoramento Ambiental , Fragaria/crescimento & desenvolvimento , Clima , Conservação dos Recursos Naturais , Eutrofização , Solo , Suíça
19.
BMC Plant Biol ; 19(1): 73, 2019 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-30764758

RESUMO

BACKGROUND: The development and ripening of fresh fruits is an important trait for agricultural production and fundamental research. Almost all plant hormones participate in this process. Strigolactones (SLs) are a new class of plant hormones that regulate plant organ development and stress tolerance, but little is known about their roles in fruit development. RESULTS: In this study, we identified SL biosynthetic and signaling genes in woodland strawberry, a typical non-climacteric fruit, and analyzed the expression patterns of these genes in different plant tissues and developing fruits. One D27, two MAX1, and one LBO gene were identified as involved in SL biosynthesis, and one D14, one D3, and two D53 genes as related to SL signaling. The proteins encoded by these genes had similar motifs as SL biosynthetic and signaling proteins in rice and Arabidopsis. The genes had different expression levels in the root, stem, leaf, and petiole of woodland strawberry. In addition, the expression of most SL biosynthetic genes was high in developing carpel, anther, and style, while that of SL signaling genes was high in carpel and style, but low in anther, suggesting active SL biosynthesis and signaling in the developing carpel and style. Notably, the expression of SL biosynthetic and signaling genes was significantly increased in the receptacle after pollination and decreased during receptacle development. Moreover, low or no expression of these genes was detected in ripening fruits. CONCLUSIONS: Our results suggest that SLs play a role in the early stages of woodland strawberry fruit development. Our findings provide insight into the function of SLs and will facilitate further study of the regulation by SLs of fresh fruit development.


Assuntos
Fragaria/genética , Regulação da Expressão Gênica de Plantas , Lactonas/metabolismo , Proteínas de Plantas/metabolismo , Transdução de Sinais , Fragaria/crescimento & desenvolvimento , Fragaria/metabolismo , Frutas/genética , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Proteínas de Plantas/genética
20.
Exp Appl Acarol ; 77(2): 133-143, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30805818

RESUMO

The contribution of generalist insect predators to the control of the two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), an herbivorous pest of many crops, is poorly understood. One of the common insect predators in strawberries is the generalist predatory bug Anthocoris nemorum L. (Hemiptera: Anthocoridae), which has the potential to contribute to the control of pest populations. The feeding of adult A. nemorum on T. urticae was assessed by sampling individuals from an organic strawberry field in Denmark, and using PCR gut content analysis to detect remains of T. urticae within their gut. In the lab, we assessed that the DNA half-life detectability was 21.5 h. Significant numbers of field-collected A. nemorum tested positive for T. urticae prey DNA, with very high numbers in June (62.8%) and August (38.8%). This study presents conclusive evidence that the generalist predator A. nemorum can contribute to the decrease of T. urticae densities in strawberry fields, although the actual contribution in the present study is probably limited because predator populations were relatively low compared to T. urticae. The abundance of T. urticae did not increase significantly during the period of sampling, suggesting that a complex of natural enemies can achieve biological control of T. urticae in protected strawberries.


Assuntos
Cadeia Alimentar , Hemípteros/fisiologia , Controle Biológico de Vetores , Comportamento Predatório , Tetranychidae , Controle de Ácaros e Carrapatos , Animais , Produtos Agrícolas/crescimento & desenvolvimento , Dinamarca , Fragaria/crescimento & desenvolvimento , Reação em Cadeia da Polimerase
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