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1.
Int J Food Microbiol ; 338: 109018, 2021 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-33310340

RESUMO

It is necessary to apply some preservatives for tomato paste since in the harvest season, a high load of tomatoes need to be processed as they are among highly perishable products. Application of antimicrobial extracts or essential oils, as natural preservatives, in their raw forms might reduce their efficiency when they are exposed to environmental conditions. However, microencapsulation is a well-known method to solve this problem. Our main goal was to restrict fungal growth rate in stored tomato paste and increase its storage stability by incorporating encapsulated olive leaf phenolic-rich extract. Total Soluble Solids (TSS), consistency, pH, color indices and diametrical growth rate of Aspergillus flavus were measured for different samples. The treatments designed in terms of considering two levels of non-encapsulated olive phenolics extract with 500 and 1000 ppm (NE500 and NE1000), the same levels with encapsulated extract; i.e., 500 and 1000 ppm (ME500 and ME1000), and similar levels of the common preservative of sodium benzoate with 500 and 1000 ppm (B500 and B1000). Antifungal properties of NE samples were higher than ME ones during storage although ME samples could maintain diametrical growth rate of the fungus more stable than NE ones. NE samples justified lower maximum growth rate than ME samples while ME samples could extend lag phase of microbial growth compared with NE one and delay their internal deteriorative reactions. Among Baranyi, modified Baranyi, Modified Gompertz, and Logistic models, Modified Gompertz model represented the best model and could fit the growth factors of A. flavus on tomato paste with higher R2 index as well as lower RMSE and SSE indices. Based on the results obtained, it could be concluded that usage of encapsulated olive leaf extract in tomato paste is an effective, natural and sustainable approach to improve the shelf life of tomato paste since this natural compound could perform as favourable as preservatives; also it could maintain physicochemical as well as microbial properties of tomato paste for a long term. Thus, it is strongly recommended that application of encapsulated olive leaf extract to be considered seriously by the tomato paste industry as it can effectively reduce the mold and fungal contaminations which are very common and prevalent in the plants. The future work in this regard should focus on sensory evaluations when incorporating encapsulated olive leaf extract into tomato paste.


Assuntos
Aspergillus flavus/efeitos dos fármacos , Microbiologia de Alimentos/métodos , Armazenamento de Alimentos/métodos , Lycopersicon esculentum/microbiologia , Olea/química , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Antifúngicos/farmacologia , Óleos Voláteis/farmacologia , Folhas de Planta/química
2.
Environ Pollut ; 269: 116218, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33316490

RESUMO

The current study for the first time demonstrates the interference of a free-living, N2-fixing, and nanoparticle (NP) tolerant Azotobacter salinestris strain ASM recovered from metal-polluted soil with tomato plant-metal oxide NPs (ZnO, CuO, Al2O3, and TiO2) interactions in a sandy clay loam soil system with bulk materials as control. Tomato plants were grown till full maturity in soils amended with 20-2000 mg kg-1 of each metal-oxide NP with and without seed biopriming and root-inoculation of A. salinestris. A. salinestris was found metabolically active, producing considerably high amounts of bioactive indole-3-acetic-acid, morphologically unaffected, and with low alteration of cell membrane permeability under 125-1500 µgml-1 of NPs. However, ZnO-NPs slightly alter bacterial membrane permeability. Besides, A. salinestris secreted significantly higher amounts of extracellular polymeric substance (EPS) even under NP exposure, which could entrap the NPs and form metal-EPS complex as revealed and quantified by SEM-EDX. NPs were also found adsorbed on bacterial biomass. EPS stabilized the NPs and provided negative zeta potential to NPs. Following soil application, A. salinestris improved the plant performance and augmented the yield of tomato fruits and lycopene content even in NPs stressed soils. Interestingly, A. salinestris inoculation enhanced photosynthetic pigment formation, flower attributes, plant and fruit biomass, and reduced proline level. Bacterial inoculation also reduced the NP's uptake and accumulation significantly in vegetative organs and fruits. The organ wise order of NP's internalization was roots > shoots > fruits. Conclusively, A. salinestris inoculation could be an alternative to increase the production of tomato in metal-oxide NPs contaminated soils.


Assuntos
Lycopersicon esculentum , Nanopartículas Metálicas , Nanopartículas , Poluentes do Solo , Óxido de Zinco , Azotobacter , Matriz Extracelular de Substâncias Poliméricas/química , Óxidos , Raízes de Plantas/química , Poluentes do Solo/análise
3.
Chemosphere ; 263: 128169, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297138

RESUMO

A hydroponic study was conducted to determine the effects of single and/or combined application of different doses (0, 5 and 10 µM L-1) of abscisic acid (ABA) and 6-benzylaminopurine (BAP) on cobalt (Co) accumulation, morpho-physiological and antioxidative defense attributes of tomato (Solanum lycopersicum L.) exposed to severe Co stress (400 µM L-1). The single Co treatment (T1), prominently decreased tomato growth, relative water contents, photosynthetic pigments (chlorophyll a and chlorophyll b), whereas enhanced oxidative stress and Co accumulation in shoot and root tissues. Nonetheless, the supplementation of ABA and 6-BAP via nutrient media significantly (P < 0.05) enhanced plant biomass, root morphology and chlorophyll contents of tomato, compared to only Co treatment (T1). Moreover, the oxidative stress indicators such as malondialdehyde, proline and H2O2 contents were ameliorated through activation of enzymatic antioxidant activities i.e. ascorbate peroxidase, superoxide dismutase, catalase, and peroxidase, in growth modulator treatments in comparison to T1. The Co uptake, translocation (TF) and bioaccumulation factor (BAF) by shoot and root tissues of tomato were significantly reduced under all the treatments than that of T1. The supply of 6-BAP alone or in combination with ABA at 10 µM L-1 application (T7) rate was found the most effective to reduce Co accumulation in the roots and shoots by 48.4% and 70.2% respectively than T1 treatment. It can be concluded that two plant growth modulators could improve the stress tolerance by inhibition of Co uptake in tomato plants.


Assuntos
Antioxidantes , Lycopersicon esculentum , Ácido Abscísico , Compostos de Benzil , Clorofila , Clorofila A , Cobalto/toxicidade , Peróxido de Hidrogênio , Folhas de Planta , Purinas
5.
Int J Food Microbiol ; 337: 108936, 2021 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-33161345

RESUMO

Development of novel and effective decontamination technologies to ensure the microbiological safety of fresh produce has gained considerable attention, mainly driven by numerous outbreaks. This work presented the first approach regarding to the application of the previously reported hurdle technologies on the sanitization of artificially contaminated cherry tomatoes. Thyme (Thymus daenensis) essential oil nanoemulsion (TEON, 8.28 nm in diameter with a narrow size distribution) was formulated via ultrasonic nanoemulsification, showing remarkably improved antimicrobial activity against Escherichia coli (E. coli) O157:H7, compared to the coarse emulsion. The antimicrobial effect of ultrasound (US), thyme essential oil nanoemulsion (TEON) and the combination of both treatments was assessed against E. coli O157:H7. The remarkable synergistic effects of the combined treatments were achieved, which decontaminated the E. coli populations by 4.49-6.72 log CFU/g on the surface of cherry tomatoes, and led to a reduction of 4.48-6.94 log CFU/sample of the total inactivation. TEON combined with US were effective in reducing the presence of bacteria in wastewater, which averted the potential detrimental effect of cross-contamination resulted from washing wastewater in fresh produce industry. Moreover, the treatments did not noticeably alter the surface color and firmness of cherry tomatoes. Therefore, ultrasound combined with TEON is a promising and feasible alternative for the reduction of microbiological contaminants, as well as retaining the quality characteristics of cherry tomatoes.


Assuntos
Descontaminação/métodos , Escherichia coli O157/efeitos dos fármacos , Escherichia coli O157/efeitos da radiação , Microbiologia de Alimentos/métodos , Óleos Voláteis/farmacologia , Ondas Ultrassônicas , Contagem de Colônia Microbiana , Lycopersicon esculentum/microbiologia
6.
J Biosci Bioeng ; 131(1): 53-60, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33082081

RESUMO

Phenolic compounds inhibit phytopathogenic fungal infections effectively. In this study, the antifungal effects of rice straw-derived phenolic acids (PAs) against Fusarium oxysporum were investigated. PAs can inhibit hyphal growth and spore germination, and p-coumaric acid (CA) is the main antifungal substance in PAs. PAs could induce the formation of hydrogen peroxide and increase the relative conductivity and extracellular K+ concentration. Observations using Scanning Electron Microscopy, Laser Scanning Confocal Microscopy and Transmission Electron Microscopy revealed that PAs could damage membrane permeability, which caused cytoplasm leakage. This phenomenon was verified by conductivity and the release of extracellular K+. The chlorophyll fluorescence maps of tomato leaves suggested that F. oxysporum damaged the tomato' photosynthetic system and that PAs reduced the area infected, thereby alleviating the damage. Moreover, PAs could decrease the disease incidence of tomato fruit. The results confirmed the feasibility of using PAs as a biofungicide and provide a way to increase the value of rice straw.


Assuntos
Agricultura/métodos , Fungicidas Industriais/farmacologia , Hidroxibenzoatos/farmacologia , Frutas/microbiologia , Fusarium/efeitos dos fármacos , Química Verde , Lycopersicon esculentum/microbiologia , Oryza/microbiologia , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia
7.
Plant Mol Biol ; 105(1-2): 65-82, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32909182

RESUMO

KEY MESSAGE: NbWRKY22 and NbWRKY25 are required for full activation of bacteria-associated pattern- and effector-triggered immunity as well as for the response to other non-bacterial defense elicitors. Plants defend themselves against pathogens using a two-layered immune system. Pattern-triggered immunity (PTI) can be activated upon recognition of epitopes from flagellin including flg22. Pseudomonas syringae pv. tomato (Pst) delivers effector proteins into the plant cell to promote host susceptibility. However, some plants express resistance (R) proteins that recognize specific effectors leading to the activation of effector-triggered immunity (ETI). Resistant tomato lines such as Rio Grande-PtoR (RG-PtoR) recognize two Pst effectors, AvrPto and AvrPtoB, and activate ETI through the Pto/Prf protein complex. Using RNA-seq, we identified two tomato WRKY transcription factor genes, SlWRKY22 and SlWRKY25, whose expression is increased during Pst-induced ETI. Silencing of the WRKY25/22 orthologous genes in Nicotiana benthamiana led to a delay in programmed cell death normally associated with AvrPto recognition or several non-bacterial effector/R protein pairs. An increase in disease symptoms was observed in silenced plants infiltrated with Pseudomonas syringae pv. tabaci expressing AvrPto or HopQ1-1. Expression of both tomato WRKY genes is also induced upon treatment with flg22 and callose deposition and cell death suppression assays in WRKY25/22-silenced N. benthamiana plants supported their involvement in PTI. Our results reveal an important role for two WRKYs as positive regulators of plant immunity against bacterial and potentially non-bacterial pathogens.


Assuntos
Imunidade Vegetal/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Tabaco/genética , Tabaco/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Apoptose , Arabidopsis/genética , Proteínas de Arabidopsis , Morte Celular , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Inativação Gênica , Genes de Plantas/genética , Lycopersicon esculentum/genética , Filogenia , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Imunidade Vegetal/genética , Proteínas de Plantas/classificação , Pseudomonas syringae/patogenicidade , Fatores de Transcrição/classificação
8.
Sci Total Environ ; 755(Pt 1): 142531, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33035975

RESUMO

The olive oil industry is an important economic sector in Mediterranean countries. However, oil production is unfortunately accompanied by the generation of huge amounts of olive mill solid wastes (OMSW) and olive mill wastewater (OMWW). In the present study, a strategy is proposed for converting these olive mill wastes into biochar through pyrolysis, for their later use as an organic amendment in agriculture. Specifically, two biochars were prepared from the pyrolysis of OMSW at 500 °C, either alone or impregnated with OMWW (OMSW-B and I-OMSW-B). The characterization of the OMSW and I-OMSW samples and their derived biochars showed that the fixed carbon and ash contents in the feedstocks increased by 38% and 11% respectively for OMSW-B, and by 37% and 12% respectively for I-OMSW-B. Interestingly, the impregnation process significantly increased Na, P, K, Ca and Fe contents in the produced biochars. The effect of OMSW-B and I-OMSW-B amendments at different application dose (1%, 2.5% and 5% wt/wt) on the enzymatic activity of an agricultural soil was performed at laboratory scale with a pot test. The experimental results showed that phosphatase and urease activity increased with biochar application rate; amendment with I-OMSW-B at 1%, 2.5% and 5% enhanced the phosphatase activity by 63%, 142% and 285% and urease activity by 50%, 116% and 149%, respectively. On the other hand, dehydrogenase and protease activities were higher for the application rate of 2.5% biochar. Biochar amendment promoted tomatoes seedling growth after 10 weeks, which was highest in the application rates of 2.5% and 5% for both OMSW-B and I-OSMW-B. Thus, the produced biochars had great potential to be used as biofertilizers in agriculture.


Assuntos
Lycopersicon esculentum , Solo , Agricultura , Carvão Vegetal
9.
Food Chem ; 338: 128126, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33091993

RESUMO

Tomato fruits contain much organic acids and γ-aminobutyric acid (GABA) during ripening which are beneficial to human health. The effects of 4 kJ/m2 UV-C treatment on the contents of organic acids and GABA, and the expression of related genes in tomato fruits during storage at 13 °C were investigated. The results showed that UV-C treatment significantly increased the organic acids and total soluble protein contents, whereas decreased the free amino acids and glutamate contents. Besides, UV-C treatment enhanced GAD activity while reduced GABA-T activity, which resulted in accumulation of GABA. Moreover, the genes involved in the biosynthesis of organic acids and GABA were up-regulated, including CS, PEPC1, PEPC2, mMDH, cMDH, GAD1, GAD2, and GAD3, while GABA-T1 and GABA-T3 which involved in GABA degradation were obviously decreased by UV-C treatment. These results indicated that UV-C treatment might be an effective approach to accumulate organic acids and GABA during tomato fruits ripening.


Assuntos
Armazenamento de Alimentos , Frutas/metabolismo , Frutas/efeitos da radiação , Lycopersicon esculentum/metabolismo , Lycopersicon esculentum/efeitos da radiação , Raios Ultravioleta , Ácido gama-Aminobutírico/metabolismo , Aminoácidos/metabolismo , Glutamato Descarboxilase/metabolismo , Ácido Glutâmico/metabolismo
10.
Food Chem ; 340: 127925, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32889213

RESUMO

The addition of strawberry pulp to ketchup sauces may be an alternative to attend the consumers' demand for innovative products with functional appeal. Sauces were made using different tomato/strawberry pulp ratios (100:0; 75:25; 50:50; 25:75; 0:100) and characterized for the physicochemical characteristics, bioactive compounds, antioxidant activity, and consumers' acceptance. The strawberry-enriched ketchup sauces presented higher phenolics, total flavonoids, antioxidant activity, and increased fluidity, and lower browning index, hue angle, chroma, pH, and Bostwick consistency. The antioxidant activities (ABTS and DPPH) were positively correlated with phenolics (r = 0.96 and 0.91) and flavonoids (r = 0.92 and 0.89) contents, respectively. The replacement of up to 50% tomato pulp by strawberry pulp did not change the acidity, flavor, and overall acceptance of the samples. The strawberry pulp has proven to be an effective alternative to increase the concentrations of bioactive compounds while reducing the amount of sugar used in traditional ketchup formulations.


Assuntos
Antioxidantes/química , Alimentos , Fragaria/química , Lycopersicon esculentum/química , Adolescente , Adulto , Feminino , Flavonoides/análise , Humanos , Masculino , Pessoa de Meia-Idade , Fenóis/análise , Paladar , Adulto Jovem
11.
Environ Pollut ; 268(Pt B): 115779, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33075680

RESUMO

Microplastics (MPs) are becoming an environmental growing concern, being the sewage sludge applied to agriculture fields one of the most important inputs to the environment. To date, there is no standardized protocol for their extraction and changes in vegetative growth and fruit maturation on cultivated plants induced by sludge containing MPs have not been studied yet. Sewage sludge from three different wastewater treatment plants located in Murcia, Spain, were studied. First, the microplastic concentration was estimated and, then, the effects of the sewage sludge in the development of tomato plants and fruit production was analyzed. The measured parameters in tomato plants were both, biomass and length, for shoot and root part, as well as, stem diameter and tomato production. The present work has developed and validated a protocol for the extraction and quantification of MPs comprising several shapes, materials and sizes from samples of sewage sludges, which offers a good compromise for the extraction of different types of microplastic. The protocol used for MPs extraction had a recovery efficiency of 80 ± 3% (mean ± SE) and used bicarbonate, to maximize MPs extraction. The mean abundance of MPs in the studied sewage sludge samples was 30,940 ± 8589 particles kg-1 dry weight. Soils with sludge containing MPs fostered the growth of tomato plants, while delaying and diminished fruit production. However, other factors or their interactions with MPs could have influenced the outcomes. Further studies are necessary to corroborate these findings and explain the mechanisms of possible effects of MPs on plants.


Assuntos
Lycopersicon esculentum , Esgotos , Frutas , Microplásticos , Plásticos , Espanha
12.
Phytochemistry ; 181: 112588, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33232863

RESUMO

Plant polyphenol oxidases (PPOs) are ubiquitous copper metalloenzymes with a biochemistry that has been known for more than a century. By the 1990s, biologists began to recognize the importance of PPOs in plant response to the infestation of herbivores and pathogens; ideas concerning a defensive role for PPOs arose to address observed evidence, and several testable hypotheses were suggested. Two pivotal discoveries in tomato (Lycopersicon esculentum Miller) plants, an inverse correlation between PPO levels and insect growth and PPO induction by defence signals, have driven many studies of PPO defence functions in the context of abiotic and biotic stresses. During the past three decades, extensive molecular research in transgenic and non-transgenic systems has partly revealed the sophisticated mechanisms underlying PPO defence against herbivores and pathogens. These understandings, rather than theoretical predictions, have driven the development of new hypotheses and advanced PPO-related studies. Here, we review progress in PPO family features, expression regulation and the defensive role of PPOs in plants. We propose assumptions of an extended range of co- and post-transcriptional processes to the regulation of unexplored PPO expression. In addition, the identification of endogenous PPO substrates and downstream targets of PPO action will be useful for elucidating PPO defensive roles. The potential effects of PPO-mediated oxidative defences on herbivore performance ultimately needs to be further investigated. Therefore, expanding multidisciplinary approaches to unexplored dimensions of PPO defence function should be a future priority.


Assuntos
Catecol Oxidase , Lycopersicon esculentum , Animais , Insetos , Lycopersicon esculentum/genética
13.
Ecotoxicol Environ Saf ; 207: 111550, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33254408

RESUMO

Cadmium (Cd) is harmful to plant growth and can be easily transferred from soil to plants. Plant cell wall plays important role in preventing Cd from entering cells. Salicylic acid (SA) mediated defense response increases plant resistance to heavy metals. In this study, all tomato seedlings were pre-treated with 100 µM SA for 3 d, then seedlings were used to analyze the role of SA in regulating plant cell wall resistance to Cd stress. The results showed that exogenous SA significantly reduced Cd accumulation in tomato plants and changed Cd distribution. By analyzing the cell wall composition, it was found cellulose, hemicellulose, pectin, and lignin were induced by SA. Interestingly, the content of Cd in pectin decreased by SA pretreatment, however it was increased in cellulose. Gene expression analysis showed SA up-regulated the expression level of lignin and cellulose synthase genes, but down-regulated the expression of pectin methylesterase related genes. In addition, SA down-regulated the activity of pectin methylesterase. These results indicated that SA pretreatment up-regulated cell wall polysaccharide synthesis and related gene expression to thicken the cell wall and block Cd from passing through. Furthermore, SA decreased pectin methylesterase activity and content to reduce cell wall Cd accumulation and change the Cd partition ratio.


Assuntos
Cádmio/metabolismo , Lycopersicon esculentum/metabolismo , Substâncias Protetoras/farmacologia , Ácido Salicílico/farmacologia , Metabolismo dos Carboidratos , Parede Celular/metabolismo , Metilação , Pectinas/metabolismo , Raízes de Plantas/metabolismo , Polissacarídeos/metabolismo , Plântula/metabolismo
14.
Pest Manag Sci ; 77(1): 33-42, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32776672

RESUMO

In recent years, the use of predatory mirid bugs (Hemiptera: Miridae) in horticultural crops has increased considerably. Mirid bugs are zoophytophagous predators, that is, they display omnivorous behavior and feed on both plants and arthropods. Mirid bugs feed effectively on a wide range of prey, such as whiteflies, lepidopteran eggs and mites. In addition, the phytophagous behavior of mirid bugs can activate defenses in the plants on which they feed. Despite the positive biological attributes, their use still presents some constraints. Their establishment and retention on the crop is not always easy and economic plant damage can be caused by some mirid species. In this review, the current strategies for using zoophytophagous mirid bugs in horticultural crops, mainly Nesidiocoris tenuis, Macrolophus pygmaeus and Dicyphus hesperus, are reviewed. We discuss six different approaches which, in our opinion, can optimize the efficacy of mirids as biocontrol agents and help expand their use into more areas worldwide. In this review we (i) highlight the large number of species and biotypes which are yet to be described and explore their applicability, (ii) present how it is possible to take advantage of the mirid-induced plant defenses to improve pest management, (iii) argue that genetic selection of improved mirid strains is feasible, (iv) explore the use of companion plants and the use of alternative foods to improve the mirid bug management, and finally (vi) discuss strategies for the expansion of mirid bugs as biological control agents to horticultural crops other than just tomatoes. © 2020 Society of Chemical Industry.


Assuntos
Heterópteros , Lycopersicon esculentum , Ácaros , Animais , Controle Biológico de Vetores , Comportamento Predatório
15.
Pest Manag Sci ; 77(1): 184-193, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32652749

RESUMO

BACKGROUND: For many insects, including invasive species, overwintering survival is achieved behaviourally (e.g. through migration) or physiologically by entering diapause, a state of arrested physiological development that may be accompanied with depressed supercooling points (SCPs). Diapause allows in situ adaptation to adverse environmental conditions, providing sufficient parent propagules for insect pest proliferation when optimal conditions resurface. This phenomenon has however not been observed in the invasive South American tomato pinworm Tuta absoluta in its Mediterranean invaded areas. Moreover, no studies have looked at its overwintering survival in sub-Saharan Africa. Here, we thus investigated the cold hardiness of Tuta absoluta larvae and adults to better explain its local overwintering adaptation strategy. RESULTS: Larval lower lethal temperatures ranged from -1 to -17 °C for 0.5 to 4 h durations. Adults showed lower temperature activity limits than larvae albeit freeze strategy experiments showed neither survived internal freezing. Fasting and dehydration pre-treatment generally depressed SCPs, although asymmetrically, conferring more negative SCPs for larvae. Ramping rates, synonymic to diurnal temperature changes also significantly affected SCPs while, inoculative freezing significantly compromised freezing temperatures in both larvae and adults. CONCLUSION: Our results suggest that (i) Tuta absoluta larvae and adults are chill-susceptible and may successfully overwinter, (ii) larvae appear more cold hardy than adults and (iii) ecological factors e.g. inoculative freezing, cooling rates, feeding- and hydration-status may affect cold hardiness. These results are important in determining species range limits, population phenology, modelling pest risk status and allows temporal life-stage specific targeting of management strategies.


Assuntos
Lepidópteros , Lycopersicon esculentum , Mariposas , África ao Sul do Saara , Animais , Temperatura Baixa , Enterobius , Larva
16.
Ying Yong Sheng Tai Xue Bao ; 31(9): 3075-3084, 2020 Sep 15.
Artigo em Chinês | MEDLINE | ID: mdl-33345509

RESUMO

To explore the mechanism of Solanum lycopersicum rootstock function in enhancing salt tolerance of grafted seedlings, we examined the growth, Na+ accumulation, amino acid contents and active oxygen metabolism (ROS) in three grafted seedlings treated with and without 175 mmol·L-1 NaCl conditions. RS grafted seedlings were formed by split grafting using salt-sensitive variety 'Zhongza 9'(S) as scion and salt-tolerant variety 'OZ-006'(R) as rootstock, while the other two experiment materials were the scion self-grafted (SS) and rootstock self-grafted (RR) seedlings. The results showed that NaCl stress significantly increased the salt damage index and Na+ content, concomitantly with substantial decrease in growth rate and chlorophyll content of seedlings. More-over, there were significant differences among the grafting combinations, with an order of SS>RS>RR. NaCl stress significantly increased total amino acid content in the leaves and roots of the grafted seedlings. The amino acid contents were significantly higher than those in the control. There were 9 kinds of amino acid in RR and RS leaves, and 8 kinds in RR and RS roots, with the most significant change in proline. Only 2 and 4 kinds of amino acids in leaves and roots of SS were significantly higher than those in control, respectively. Amino acid contents among three grafted seedlings showed RR>RS>SS under NaCl stress. The contents of amino acid in RR and RS leaves increased by 32.8% and 16.6% compared with SS, and those in RR and RS roots increased by 53.1% and 32.5%, respectively. The changes of ROS were caused by NaCl stress, which enhanced the activities of antioxidant enzymes, the production rate of O2-· and MDA content in both leaves and roots. Among different grafted seedlings, RR had the most prominent increase of antioxidant enzymes activities in leaves and roots, followed by RS, and SS showed the smallest. The active oxygen levels among the three grafted seedlings were show as SS>RS>RR. In summary, rootstock alleviated salt damage of grafted seedlings by inhibiting Na+ transport upward, enhancing amino acid content and antioxidant enzyme activities. The salt tolerance ability showed remarkable difference among three different combinations of rootstock and scion, with a order of RR>RS>SS. Our results suggested that salt tolerance of S. lycopersicum grafted seedlings was mainly affected by the ability of rootstock salt tolerance, followed by scion, and also closely related to the regulation of both amino acid and active oxygen metabolism in seedlings.


Assuntos
Lycopersicon esculentum , Plântula , Biomassa , Folhas de Planta , Raízes de Plantas , Espécies Reativas de Oxigênio , Estresse Fisiológico
17.
PLoS One ; 15(11): e0241317, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33232332

RESUMO

Plant grafting is a sequential wound healing process. However, whether wounding induces a different jasmonic acid (JA) response within half a day (12 h) after grafting or non-grafting remains unclear. Using the tomato hypocotyl grafting method, we show that grafting alleviates the asymmetrical accumulation of JA and jasmonic acid isoleucine conjugate (JA-Ile) in scion and rootstock caused by wounding, and from 2 h after tomato micrografting, grafting obviously restored the level of JA-Ile in the scion and rootstock. Meanwhile, five JA-related genes, SlLOX11, SlAOS, SlCOI1, SlLAPA and SlJA2L, are detected and show significant changes in transcriptional expression patterns within 12 h of grafting, from asymmetrical to symmetrical, when the expression of 30 JA- and defense-related genes were analyzed. The results indicated that grafting alleviates the asymmetrical JA and defense response between scion and rootstock of the tomato hypocotyl within 12 h as induced by wounding. Moreover, we demonstrate that in the very early hours after grafting, JA-related genes may be involved in a molecular mechanism that changes asymmetrical expression as induced by wounding between scion and rootstock, thereby promoting wound healing and grafting success.


Assuntos
Ciclopentanos/farmacologia , Hipocótilo/fisiologia , Lycopersicon esculentum/fisiologia , Oxilipinas/farmacologia , Técnicas de Cultura de Tecidos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Hipocótilo/efeitos dos fármacos , Hipocótilo/genética , Isoleucina/análogos & derivados , Isoleucina/farmacologia , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/genética , Transdução de Sinais/genética
18.
Sensors (Basel) ; 20(22)2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33187119

RESUMO

Greenhouses and indoor farming systems play an important role in providing fresh and nutritious food for the growing global population. Farms are becoming larger and greenhouse growers need to make complex decisions to maximize production and minimize resource use while meeting market requirements. However, highly skilled labor is increasingly lacking in the greenhouse sector. Moreover, extreme events such as the COVID-19 pandemic, can make farms temporarily less accessible. This highlights the need for more autonomous and remote-control strategies for greenhouse production. This paper describes and analyzes the results of the second "Autonomous Greenhouse Challenge". In this challenge, an experiment was conducted in six high-tech greenhouse compartments during a period of six months of cherry tomato growing. The primary goal of the greenhouse operation was to maximize net profit, by controlling the greenhouse climate and crop with AI techniques. Five international teams with backgrounds in AI and horticulture were challenged in a competition to operate their own compartment remotely. They developed intelligent algorithms and use sensor data to determine climate setpoints and crop management strategy. All AI supported teams outperformed a human-operated greenhouse that served as reference. From the results obtained by the teams and from the analysis of the different climate-crop strategies, it was possible to detect challenges and opportunities for the future implementation of remote-control systems in greenhouse production.


Assuntos
Inteligência Artificial , Infecções por Coronavirus/epidemiologia , Lycopersicon esculentum/crescimento & desenvolvimento , Pandemias , Pneumonia Viral/epidemiologia , Agricultura/tendências , Betacoronavirus/patogenicidade , Clima , Humanos
19.
An Acad Bras Cienc ; 92(3): e20190254, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33206797

RESUMO

Plant responses to nitrogen supply are dependent on auxin signaling, but much still remains to be elucidated regarding N deficiency in tomato. Thus, the objective of this work was to evaluate how low auxin sensitivity regulates the responses of tomato plants to N deficiency. For this purpose, we used the tomato diageotropica mutant, with low auxin sensitivity, and a near isogenic line cv. Micro-Tom grown in nutrient solutions under absence and presence of nitrogen. Plant height, stem diameter, root and shoot dry mass, area and root density, number of lateral roots, leaf area, chlorophylls and carotenoids content, nitrogen accumulation and nitrogen use efficiency were evaluated. We observed a clear interaction between the tomato genotype and nitrogen. When the plants were grown with nitrogen, 'Micro-Tom' showed higher growth than the diageotropica mutant. Under nitrogen deficiency condition, the mutant showed improved growth, nitrogen use efficiency and higher contents of pigments. In general, the low sensitivity to auxin in diageotropica caused reduced growth in both shoot and root. However, the diageotropica tomato showed a positive regulation of the nitrogen use efficiency under nitrogen deficiency. In general, our data revealed that the reduced sensitivity to auxin increased the adaptive capacity to the nitrogen deficiency.


Assuntos
Ácidos Indolacéticos , Lycopersicon esculentum , Ácidos Indolacéticos/farmacologia , Lycopersicon esculentum/genética , Nitrogênio , Folhas de Planta , Raízes de Plantas
20.
PLoS One ; 15(11): e0242723, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33237964

RESUMO

Physical interaction between two proteins is strong evidence that the proteins are involved in the same biological process, making Protein-Protein Interaction (PPI) networks a valuable data resource for predicting the cellular functions of proteins. However, PPI networks are largely incomplete for non-model species. Here, we tested to what extent these incomplete networks are still useful for genome-wide function prediction. We used two network-based classifiers to predict Biological Process Gene Ontology terms from protein interaction data in four species: Saccharomyces cerevisiae, Escherichia coli, Arabidopsis thaliana and Solanum lycopersicum (tomato). The classifiers had reasonable performance in the well-studied yeast, but performed poorly in the other species. We showed that this poor performance can be considerably improved by adding edges predicted from various data sources, such as text mining, and that associations from the STRING database are more useful than interactions predicted by a neural network from sequence-based features.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Escherichia coli , Escherichia coli , Lycopersicon esculentum , Anotação de Sequência Molecular , Mapas de Interação de Proteínas/fisiologia , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Lycopersicon esculentum/genética , Lycopersicon esculentum/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
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