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1.
J Appl Microbiol ; 130(1): 179-195, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32590882

RESUMO

AIMS: Sustainable agriculture requires effective and safe biofertilizers and biofungicides with low environmental impact. Natural ecosystems that closely resemble the conditions of biosaline agriculture may present a reservoir for fungal strains that can be used as novel bioeffectors. METHODS AND RESULTS: We isolated a library of fungi from the rhizosphere of three natural halotolerant plants grown in the emerging tidal salt marshes on the south-east coast of China. DNA barcoding of 116 isolates based on the rRNA ITS1 and 2 and other markers (tef1 or rpb2) revealed 38 fungal species, including plant pathogenic (41%), saprotrophic (24%) and mycoparasitic (28%) taxa. The mycoparasitic fungi were mainly species from the hypocrealean genus Trichoderma, including at least four novel phylotypes. Two of them, representing the taxa Trichoderma arenarium sp. nov. (described here) and T. asperelloides, showed antagonistic activity against five phytopathogenic fungi, and significant growth promotion on tomato seedlings under the conditions of saline agriculture. CONCLUSIONS: Trichoderma spp. of salt marshes play the role of natural biological control in young soil ecosystems with a putatively premature microbiome. SIGNIFICANCE AND IMPACT OF THE STUDY: The saline soil microbiome is a rich source of halotolerant bioeffectors that can be used in biosaline agriculture.


Assuntos
Agricultura/métodos , Águas Salinas , Trichoderma/fisiologia , Áreas Alagadas , Antibiose , China , Fungos/classificação , Fungos/genética , Fungos/metabolismo , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/microbiologia , Rizosfera , Plântula/crescimento & desenvolvimento , Plântula/microbiologia , Microbiologia do Solo , Trichoderma/classificação , Trichoderma/genética , Trichoderma/metabolismo
2.
BMC Plant Biol ; 20(1): 562, 2020 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-33317459

RESUMO

BACKGROUND: Flower development directly affects fruit production in tomato. Despite the framework mediated by ABC genes have been established in Arabidopsis, the spatiotemporal precision of floral development in tomato has not been well examined. RESULTS: Here, we analyzed a novel tomato stamenless like flower (slf) mutant in which the development of stamens and carpels is disturbed, with carpelloid structure formed in the third whorl and ectopic formation of floral and shoot apical meristem in the fourth whorl. Using bulked segregant analysis (BSA), we assigned the causal mutation to the gene Solanum lycopersicum GT11 (SlGT11) that encodes a transcription factor belonging to Trihelix gene family. SlGT11 is expressed in the early stages of the flower and the expression becomes more specific to the primordium position corresponding to stamens and carpels in later stages of the floral development. Further RNAi silencing of SlGT11 verifies the defective phenotypes of the slf mutant. The carpelloid stamen in slf mutant indicates that SlGT11 is required for B-function activity in the third whorl. The failed termination of floral meristem and the occurrence of floral reversion in slf indicate that part of the C-function requires SlGT11 activity in the fourth whorl. Furthermore, we find that at higher temperature, the defects of slf mutant are substantially enhanced, with petals transformed into sepals, all stamens disappeared, and the frequency of ectopic shoot/floral meristem in fourth whorl increased, indicating that SlGT11 functions in the development of the three inner floral whorls. Consistent with the observed phenotypes, it was found that B, C and an E-type MADS-box genes were in part down regulated in slf mutants. CONCLUSIONS: Together with the spatiotemporal expression pattern, we suggest that SlGT11 functions in floral organ patterning and maintenance of floral determinacy in tomato.


Assuntos
Flores/crescimento & desenvolvimento , Lycopersicon esculentum/genética , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Flores/genética , Regulação da Expressão Gênica de Plantas , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/metabolismo , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo
3.
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
4.
Nat Commun ; 11(1): 5343, 2020 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-33093443

RESUMO

Plants transmit signals long distances, as evidenced in grafting experiments that create distinct rootstock-scion junctions. Noncoding small RNA is a signaling molecule that is graft transmissible, participating in RNA-directed DNA methylation; but the meiotic transmissibility of graft-mediated epigenetic changes remains unclear. Here, we exploit the MSH1 system in Arabidopsis and tomato to introduce rootstock epigenetic variation to grafting experiments. Introducing mutations dcl2, dcl3 and dcl4 to the msh1 rootstock disrupts siRNA production and reveals RdDM targets of methylation repatterning. Progeny from grafting experiments show enhanced growth vigor relative to controls. This heritable enhancement-through-grafting phenotype is RdDM-dependent, involving 1380 differentially methylated genes, many within auxin-related gene pathways. Growth vigor is associated with robust root growth of msh1 graft progeny, a phenotype associated with auxin transport based on inhibitor assays. Large-scale field experiments show msh1 grafting effects on tomato plant performance, heritable over five generations, demonstrating the agricultural potential of epigenetic variation.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Lycopersicon esculentum/genética , Proteína MutS de Ligação de DNA com Erro de Pareamento/genética , Proteínas de Plantas/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/fisiologia , Proteínas de Arabidopsis/fisiologia , Metilação de DNA , Epigênese Genética , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/fisiologia , Proteína MutS de Ligação de DNA com Erro de Pareamento/fisiologia , Mutação , Fenótipo , Melhoramento Vegetal , Proteínas de Plantas/fisiologia , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/fisiologia , Plantas Geneticamente Modificadas , RNA de Plantas/genética , RNA de Plantas/metabolismo , RNA Interferente Pequeno/genética , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
5.
Proc Natl Acad Sci U S A ; 117(38): 23970-23981, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32883877

RESUMO

Fruit set is the process whereby ovaries develop into fruits after pollination and fertilization. The process is induced by the phytohormone gibberellin (GA) in tomatoes, as determined by the constitutive GA response mutant procera However, the role of GA on the metabolic behavior in fruit-setting ovaries remains largely unknown. This study explored the biochemical mechanisms of fruit set using a network analysis of integrated transcriptome, proteome, metabolome, and enzyme activity data. Our results revealed that fruit set involves the activation of central carbon metabolism, with increased hexoses, hexose phosphates, and downstream metabolites, including intermediates and derivatives of glycolysis, the tricarboxylic acid cycle, and associated organic and amino acids. The network analysis also identified the transcriptional hub gene SlHB15A, that coordinated metabolic activation. Furthermore, a kinetic model of sucrose metabolism predicted that the sucrose cycle had high activity levels in unpollinated ovaries, whereas it was shut down when sugars rapidly accumulated in vacuoles in fruit-setting ovaries, in a time-dependent manner via tonoplastic sugar carriers. Moreover, fruit set at least partly required the activity of fructokinase, which may pull fructose out of the vacuole, and this could feed the downstream pathways. Collectively, our results indicate that GA cascades enhance sink capacities, by up-regulating central metabolic enzyme capacities at both transcriptional and posttranscriptional levels. This leads to increased sucrose uptake and carbon fluxes for the production of the constituents of biomass and energy that are essential for rapid ovary growth during the initiation of fruit set.


Assuntos
Frutas , Giberelinas/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Carbono/metabolismo , Frutas/genética , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Lycopersicon esculentum/genética , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/metabolismo , Redes e Vias Metabólicas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Sacarose/metabolismo , Transcriptoma/genética
6.
Sci Rep ; 10(1): 15642, 2020 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-32973225

RESUMO

In semiarid regions is important to use native strains best adapted to these environments to optimize plant-PGPR interaction. We aimed to isolate and characterize PGPR from roots and rhizosphere of a tomato crop, as well as studying the effect of its inoculation on tomato seedlings growth. We selected four strains considering their effectiveness of fixing nitrogen, solubilizing phosphate, producing siderophores and indole acetic acid. They belong to the genera Enterobacter, Pseudomonas, Cellulosimicrobium, and Ochrobactrum. In addition, we also analyzed the ability to solubilize Ca3(PO4)2, FePO4 and AlPO4 and the presence of one of the genes encoding the cofactor PQQ in their genome. Enterobacter 64S1 and Pseudomonas 42P4 showed the highest phosphorus solubilizing activity and presence of pqqE gene. Furthermore, in a tomato-based bioassay in speed-bed demonstrated that a sole inoculation at seedling stage with the strains increased dry weight of roots (49-88%) and shoots (39-55%), stem height (8-13%) and diameter (5-8%) and leaf area (22-31%) and were equal or even higher than fertilization treatment. Leaf nitrogen and chlorophyll levels were also increased (50-80% and 26-33%) compared to control. These results suggest that Enterobacter 64S1 and Pseudomonas 42P4 can be used as bio-inoculant in order to realize a nutrient integrated management.


Assuntos
Bactérias/isolamento & purificação , Fertilizantes , Lycopersicon esculentum/microbiologia , Raízes de Plantas/microbiologia , Rizosfera , Plântula/crescimento & desenvolvimento , Bactérias/genética , Bactérias/metabolismo , Genes Bacterianos/genética , Lycopersicon esculentum/crescimento & desenvolvimento , Fixação de Nitrogênio , Fosfatos/química , Sideróforos/biossíntese , Solubilidade
7.
Nat Genet ; 52(10): 1111-1121, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32989321

RESUMO

Wild tomato species represent a rich gene pool for numerous desirable traits lost during domestication. Here, we exploited an introgression population representing wild desert-adapted species and a domesticated cultivar to establish the genetic basis of gene expression and chemical variation accompanying the transfer of wild-species-associated fruit traits. Transcriptome and metabolome analysis of 580 lines coupled to pathogen sensitivity assays resulted in the identification of genomic loci associated with levels of hundreds of transcripts and metabolites. These associations occurred in hotspots representing coordinated perturbation of metabolic pathways and ripening-related processes. Here, we identify components of the Solanum alkaloid pathway, as well as genes and metabolites involved in pathogen defense and linking fungal resistance with changes in the fruit ripening regulatory network. Our results outline a framework for understanding metabolism and pathogen resistance during tomato fruit ripening and provide insights into key fruit quality traits.


Assuntos
Resistência à Doença/genética , Lycopersicon esculentum/genética , Metaboloma/genética , Transcriptoma/genética , Alcaloides/genética , Domesticação , Frutas/genética , Frutas/crescimento & desenvolvimento , Frutas/parasitologia , Fungos/genética , Fungos/patogenicidade , Regulação da Expressão Gênica de Plantas/genética , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/microbiologia , Redes e Vias Metabólicas/genética , Fenótipo , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Solanum/genética , Solanum/microbiologia
8.
Sci Rep ; 10(1): 15970, 2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-32994443

RESUMO

Plant roots are able to exude vast amounts of metabolites into the rhizosphere in response to phosphorus (P) deficiency. Causing noteworthy costs in terms of energy and carbon (C) for the plants. Therefore, it is suggested that exudates reacquisition by roots could represent an energy saving strategy of plants. This study aimed at investigating the effect of P deficiency on the ability of hydroponically grown tomato plants to re-acquire specific compounds generally present in root exudates by using 13C-labelled molecules. Results showed that P deficient tomato plants were able to take up citrate (+ 37%) and malate (+ 37%), particularly when compared to controls. While glycine (+ 42%) and fructose (+ 49%) uptake was enhanced in P shortage, glucose acquisition was not affected by the nutritional status. Unexpectedly, results also showed that P deficiency leads to a 13C enrichment in both tomato roots and shoots over time (shoots-+ 2.66‰, roots-+ 2.64‰, compared to control plants), probably due to stomata closure triggered by P deficiency. These findings highlight that tomato plants are able to take up a wide range of metabolites belonging to root exudates, thus maximizing C trade off. This trait is particularly evident when plants grew in P deficiency.


Assuntos
Exsudatos e Transudatos/química , Lycopersicon esculentum/crescimento & desenvolvimento , Fósforo/metabolismo , Isótopos de Carbono/química , Ácido Cítrico/química , Ácido Cítrico/metabolismo , Exsudatos e Transudatos/metabolismo , Frutose/química , Frutose/metabolismo , Glicina/química , Glicina/metabolismo , Hidroponia/métodos , Lycopersicon esculentum/química , Lycopersicon esculentum/metabolismo , Malatos/química , Malatos/metabolismo , Raízes de Plantas/química
9.
Sci Rep ; 10(1): 13729, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32792530

RESUMO

Continuous cropping of tomato is increasingly practiced in greenhouse cultivation, leading to several soil-related obstacles. In this study, a type of microbial restoration substrate (MRS) was used to amend soils from the re-cropping of tomato for 8 years under greenhouse-cultivated conditions. Two treatments were established: using 1,500 kg hm-2 of MRS to amend soil as treatment (TR), and non-MRS as control (CK). The severity of bacterial wilt (BW), soil properties and rhizobacterial community composition under two different treatments were compared. The application of MRS led to an average 83.75% reduction in the severity of BW, and significantly increased the plant height, root activity and yield. Meanwhile, soil pH, soil organic contents (SOC), total nitrogen (TN) and exchangeable calcium were significantly increased (P < 0.05) by MRS treatment. Illumina-MiSeq sequencing analysis of the 16S rRNA genes revealed that MRS increased the diversity of the tomato rhizobacterial community. The relative abundances of Proteobacteria, Actinobacteria and Bacteroidetes were enhanced, whereas those of Acidobacteria, Chloroflexi, TM7 and Firmicutes were decreased by MRS. The redundancy analysis (RDA) revealed that the severity of tomato BW was negatively correlated with the relative abundances of Actinobacteria, Bacteroidetes and Proteobacteria, but positively correlated with those of Gemmatimonadetes, Firmicutes and Acidobacteria. In addition, the effects of MRS on rhizobacterial metabolic potentials were predicted using a Kyoto Encyclopedia of Genes and Genomes (KEGG) database, implying that MRS could significantly increase nitrogen metabolisms and reduce carbon metabolism. Together, our results indicated that the use of MRS could reestablish soil microbial communities, which was beneficial to plant health compared with the control.


Assuntos
Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/microbiologia , Microbiota/fisiologia , Desenvolvimento Vegetal/efeitos dos fármacos , Acidobacteria/genética , Acidobacteria/fisiologia , Actinobacteria/genética , Actinobacteria/fisiologia , Bactérias/genética , Biodiversidade , Carbono/metabolismo , Microbiota/genética , Nitrogênio/metabolismo , Proteobactérias/genética , Proteobactérias/fisiologia , RNA Ribossômico 16S/genética , Rizosfera , Solo/química , Microbiologia do Solo
10.
Sci Rep ; 10(1): 14000, 2020 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-32814781

RESUMO

'Candidatus Liberibacter solanacearum' (Lso) is a pathogen of solanaceous crops. Two haplotypes of Lso (LsoA and LsoB) are present in North America; both are transmitted by the tomato psyllid, Bactericera cockerelli (Sulc), in a circulative and propagative manner and cause damaging plant diseases (e.g. Zebra chip in potatoes). In this study, we investigated the acquisition and transmission of LsoA or LsoB by the tomato psyllid. We quantified the titer of Lso haplotype A and B in adult psyllid guts after several acquisition access periods (AAPs). We also performed sequential inoculation of tomato plants by adult psyllids following a 7-day AAP and compared the transmission of each Lso haplotype. The results indicated that LsoB population increased faster in the psyllid gut than LsoA. Further, LsoB population plateaued after 12 days, while LsoA population increased slowly during the 16 day-period evaluated. Additionally, LsoB had a shorter latent period and higher transmission rate than LsoA following a 7 day-AAP: LsoB was first transmitted by the adult psyllids between 17 and 21 days following the beginning of the AAP, while LsoA was first transmitted between 21 and 25 days after the beginning of the AAP. Overall, our data suggest that the two Lso haplotypes have distinct acquisition and transmission rates. The information provided in this study will improve our understanding of the biology of Lso acquisition and transmission as well as its relationship with the tomato psyllid at the gut interface.


Assuntos
Haplótipos , Hemípteros/microbiologia , Insetos Vetores/microbiologia , Lycopersicon esculentum/crescimento & desenvolvimento , Animais , Hemípteros/fisiologia , Insetos Vetores/fisiologia , /fisiologia , Lycopersicon esculentum/microbiologia , Lycopersicon esculentum/parasitologia , Doenças das Plantas/microbiologia , Doenças das Plantas/parasitologia , Fatores de Tempo
11.
PLoS One ; 15(8): e0237031, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32790698

RESUMO

Tomato is the most widespread vegetable crop in the world. In Italy, tomatoes are mainly cultivated in the South and in the Campania region, precisely in the area called Agro Nocerino-Sarnese. This flatland is affected by an extreme level of environmental degradation, especially related to the Sarno River, where concentrations of Potential Toxic Elements (PTEs) have been found to be higher than the maximum permitted level. The aim of this study was to determine the PTEs uptake by roots and their translocation to the aerial parts of the plants of two cultivars of tomatoes (Pomodoro Giallo and San Marzano Cirio 3). To the purpose, samples of the two cultivars were grown both in pots with experimentally contaminated soil containing: Cr or Cd or Pb at extremely high concentrations and in pots with uncontaminated soils (control). Additionally, the antioxidant properties of the cultivars selected grown on uncontaminated/contaminated soils were assessed. The results showed that Cd was the contaminant that most significantly interfered with the growth of both cultivars of tomato plants, whereas Pb caused lower phenotypical damage. Cd translocation from root to the organs of tomato plants was observed in both cultivars. Specifically, the total amount of Cd found in stems and leaves was higher in the Pomodoro Giallo (254.4 mg/kg dry weight) than in the San Marzano Cirio 3 (165.8 mg/kg dry weight). Cd was the only PTE found in the fruits of both cultivars, with values of 6.1 and 3.9 mg/kg dry weight of Pomodoro Giallo and San Marzano Cirio 3, respectively. The fruits of tomato plants grown in PTEs-contaminated soil showed inhibition or stimulations of the radical scavenging activity compared to the fruits grown in uncontaminated soil. This study highlighted that, despite the relatively high experimental concentrations of PTEs, their translocation to the edible part was comparatively low or absent.


Assuntos
Lycopersicon esculentum/metabolismo , Metais Pesados/farmacocinética , Poluentes do Solo/farmacocinética , Bioacumulação , Transporte Biológico Ativo , Cádmio/farmacocinética , Cádmio/toxicidade , Cromo/farmacocinética , Cromo/toxicidade , Depuradores de Radicais Livres/metabolismo , Radicais Livres/metabolismo , Itália , Chumbo/farmacocinética , Chumbo/toxicidade , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/crescimento & desenvolvimento , Metais Pesados/toxicidade , Poluentes do Solo/toxicidade , Distribuição Tecidual
12.
Sci Rep ; 10(1): 13535, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32782333

RESUMO

Grafting with vigorous rootstocks could offer tomato growers in Texas sustainable and efficient option to achieve reliable yield across a range of production systems and locations. Genotypes (G) of grafted and non-grafted tomato were grown in different environments (E) in the 2017 and 2018 spring seasons. The objectives of the study were to (i) evaluate the effects of production system and grafting on tomato yield traits, (ii) determine the size of genotypic and genotype by environment interaction (G × E) variance components, and (iii) evaluate the relative stability of tested genotypes for yield and its components across production environments. In 2017, genotypes were non-grafted 'TAMU Hot Ty' (TAM) and 'Tycoon' (TY) and each grafted on commercial tomato rootstocks 'Estamino' (TAM/ES, TY/ES) and 'Multifort' (TAM/MU, TY/MU) while in 2018, TAM and 'HM1823' (HM) were grafted on 'Estamino' (TAM/ES, HM/ES) and 'Multifort' (TAM/MU, HM/MU). Testing environments were high tunnel (HT) and open-field (OF) in Uvalde in 2017 while in 2018, these were HT and OF in Lubbock (LU-HT, LU-OF), Overton (OV-HT, OV-OF), Uvalde (UV-HT, UV-OF), and Weslaco (WE-HT, WE-OF). Total and marketable yields, fruit number per plant, and average fruit weight were significantly affected by E, G, and G × E interaction. Environmental component contributed 71-86% to the total variation for all these traits, while genotype explained 1.5-10.8%, and the contribution of G × E ranged between 4.3 to 6.7%. Estimation of the univariate statistic parameters and genotype plus genotype × environment (GGE) biplot analysis indicated that HM/MU and HM/ES were the most stable graft combination with the highest total and marketable yields, while TAM/ES was very unstable for yields across test environments. TAM/MU was stable but with yield lower than the grand mean. These results suggest that high tomato yields could be consistently achieved with grafted combination (HM/MU and HM/ES) especially under high tunnel production system across the regions of Texas.


Assuntos
Frutas/crescimento & desenvolvimento , Interação Gene-Ambiente , Genótipo , Lycopersicon esculentum/crescimento & desenvolvimento , Fenótipo , Frutas/genética , Lycopersicon esculentum/genética , Estações do Ano , Texas
13.
Ecotoxicol Environ Saf ; 203: 110978, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32678757

RESUMO

In this study, hydroponic experiments were conducted to elucidate mechanism(s) that are associated with differential effects of low (5 µM) and high (25 µM) dose of cadmium (Cd) stress in tomato. Furthermore, emphasis has also been focused on any involvement of endogenous hydrogen sulfide (H2S) in differential behaviour of low and high doses of Cd stress. At low dose of Cd, root growth i.e. root fresh weight, length and fitness did not significantly alter when compared to the control seedlings. Though at low dose of Cd, cellular accumulation of Cd was slightly increased but this was accompanied by higher endogenous H2S and phytochelatins, L-cysteine desulfhydrase (DES) activity, activities of glutathione biosynthetic and AsA-GSH cycle enzymes, and maintained redox status of ascorbate and glutathione. However, addition of hypotaurine (HT, a scavenger of H2S) resulted in greater toxicity, even at low dose of Cd, and these responses resembled with higher dose of Cd stress such as greater decline in root growth, endogenous H2S and phytochelatins, activities of DES, glutathione biosynthesis and AsA-GSH cycle enzymes, disturbed redox status of ascorbate and glutathione which collectively led to higher oxidative stress in tomato roots. Moreover, addition of HT with higher dose of Cd also further enhanced its toxicity. Collectively, the results showed that differential behaviour of low and high dose of Cd stress is mediated by differential regulation of biochemical attributes in which endogenous H2S has a crucial role.


Assuntos
Cádmio/toxicidade , Sulfeto de Hidrogênio/metabolismo , Lycopersicon esculentum/efeitos dos fármacos , Fitoquelatinas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Poluentes do Solo/toxicidade , Ácido Ascórbico/metabolismo , Glutationa/metabolismo , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo
14.
Sci Rep ; 10(1): 12704, 2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-32728091

RESUMO

The role of root exudates in mediating plant-microbe interactions has been well documented. However, the function of volatile organic compounds (VOCs) emitted by plant roots has only recently begun to attract attention. This newly recognized relevance of belowground VOCs has so far mostly been tested using systems limited to a two-compartment Petri-dish design. Furthermore, many of the plant-microbe interaction studies have only investigated the effects of microbial VOCs on plant growth. Here, we go two steps further. First we investigated the volatile profile of healthy and pathogen (Fusarium oxysporum) infected tomato roots grown in soil. We then used a unique soil-based olfactometer-choice assay to compare the migration pattern of four beneficial bacteria (Bacillus spp.) towards the roots of the tomato plants. We demonstrate that the blend of root-emitted VOCs differs between healthy and diseased plants. Our results show that VOCs are involved in attracting bacteria to plant roots.


Assuntos
Bacillus/isolamento & purificação , Fusarium/patogenicidade , Lycopersicon esculentum/crescimento & desenvolvimento , Compostos Orgânicos Voláteis/análise , Bacillus/genética , Bacillus/crescimento & desenvolvimento , Cromatografia Gasosa , DNA Bacteriano/genética , Lycopersicon esculentum/química , Lycopersicon esculentum/microbiologia , Metabolômica , Extratos Vegetais/análise , Raízes de Plantas/química , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Microbiologia do Solo
15.
Plant Physiol Biochem ; 154: 409-418, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32650255

RESUMO

The WRKY transcription factors (TFs) are involved in aluminum (Al) stress and jasmonic acid (JA)-regulated resistance responses. WRKYs act as regulators of Al-activated malate transporter (ALMT) proteins (anion channels) by directly binding to their promoters and altering malate efflux, thereby regulating Al ion toxicity in plant roots. JA enhances Al-induced root growth inhibition in Arabidopsis. However, the relationship between WRKY and ALMT genes and their involvement in JA-mediated root growth inhibition during Al stress in tomato remain unknown. Here, we demonstrate a similar phenomenon that JA enhances Al-induced root growth inhibition in tomato (Solanum lycopersicum). By analyzing RNA-seq data and tissue-specific expression data from public databases, we selected 17 WRKY and 6 ALMT family genes to identify the genes participated in this process. The promoters of many of the selected genes contained MeJA responsive element, G-box (target site of MYC2, a core TF of JA signaling), and W-box (target site for WRKY). Quantitative real-time PCR was performed to evaluate the expression levels of selected WRKY and ALMT genes under AlCl3 and Methyl jasmonate (MeJA) treatment. SlMYC2-VIGS seedlings and jasmonic acid-insensitive1 (jai1) mutant were also employed to analyze the expression patterns of selected genes. We find that SlALMT3 is responsible for the crosstalk regulatory mechanism between Al and JA in root growth inhibition, and 6 SlWRKYs may act as the upstream regulators of SlALMT3 in this crosstalk response. This study is initial and informative in exploring the crosstalk regulatory mechanism between JA and Al in tomato.


Assuntos
Alumínio/farmacologia , Ciclopentanos/farmacologia , Lycopersicon esculentum/crescimento & desenvolvimento , Oxilipinas/farmacologia , Proteínas de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Fatores de Transcrição/genética , Regulação da Expressão Gênica de Plantas , Lycopersicon esculentum/genética , Raízes de Plantas/efeitos dos fármacos
16.
Appl Environ Microbiol ; 86(18)2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32680869

RESUMO

Hand hygiene interventions are critical for reducing farmworker hand contamination and preventing the spread of produce-associated illness. Hand hygiene effectiveness may be produce-commodity specific, which could influence implementation strategies. This study's goal was to determine if produce commodity influences the ability of handwashing with soap and water or two-step alcohol-based hand sanitizer (ABHS) interventions to reduce soil and bacteria on farmworker hands. Farmworkers (n = 326) harvested produce (cantaloupe, jalapeño, and tomato) for 30 to 90 minutes before engaging in handwashing, two-step ABHS (jalapeño and cantaloupe), or no hand hygiene. Hands were rinsed to measure amounts of soil (absorbance at 600 nm) and indicator bacteria (coliforms, Enterococcus sp., generic Escherichia coli, and Bacteroidales universal [AllBac] and human-specific [BFD] 16S rRNA gene markers). Without hand hygiene, bacterial concentrations (0.88 to 5.1 log10 CFU/hand) on hands significantly differed by the produce commodity harvested. Moderate significant correlations (ρ = -0.41 to 0.56) between soil load and bacterial concentrations were observed. There were significant produce-commodity-specific differences in the ability of handwashing and two-step ABHS interventions to reduce soil (P < 0.0001), coliforms (P = 0.002), and Enterococcus sp. (P = 0.003), but not the Bacteroidales markers AllBac (P = 0.4) or BFD (P = 0.3). Contamination on hands of farmworkers who harvested cantaloupe was more difficult to remove. Overall, we found that a two-step ABHS intervention was similar to handwashing with soap and water at reducing bacteria on farmworker hands. In summary, produce commodity type should be considered when developing hand hygiene interventions on farms.IMPORTANCE This study demonstrated that the type of produce commodity handled influences the ability of handwashing with soap and water or a two-step alcohol-based hand sanitizer (ABHS) intervention to reduce soil and bacterial hand contamination. Handwashing with soap and water, as recommended by the FDA's Produce Safety Rule, when tested in three agricultural environments, does not always reduce bacterial loads. Consistent with past results, we found that the two-step ABHS method performed similarly to handwashing with soap and water but also does not always reduce bacterial loads in these contexts. Given the ease of use of the two-step ABHS method, which may increase compliance, the two-step ABHS method should be further evaluated and possibly considered for implementation in the agricultural environment. Taken together, these results provide important information on hand hygiene effectiveness in three agricultural contexts.


Assuntos
Carga Bacteriana/efeitos dos fármacos , Produção Agrícola , Produtos Agrícolas/classificação , Desinfecção das Mãos/instrumentação , Higienizadores de Mão/administração & dosagem , Mãos/microbiologia , Solo , Capsicum/crescimento & desenvolvimento , Cucumis melo/crescimento & desenvolvimento , Etanol/química , Fazendeiros , Higienizadores de Mão/química , Humanos , Lycopersicon esculentum/crescimento & desenvolvimento , México
17.
Sci Rep ; 10(1): 10645, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32606421

RESUMO

Tomato is one of the most widely cultivated vegetable crops and a model for studying fruit biology. Although several genes involved in the traits of fruit quality, development and size have been identified, little is known about the regulatory genes controlling its growth. In this study, we characterized the role of the tomato SlCDF4 gene in fruit development, a cycling DOF-type transcription factor highly expressed in fruits. The targeted overexpression of SlCDF4 gene in the fruit induced an increased yield based on a higher amount of both water and dry matter accumulated in the fruits. Accordingly, transcript levels of genes involved in water transport and cell division and expansion during the fruit enlargement phase also increased. Furthermore, the larger amount of biomass partitioned to the fruit relied on the greater sink strength of the fruits induced by the increased activity of sucrose-metabolising enzymes. Additionally, our results suggest a positive role of SlCDF4 in the gibberellin-signalling pathway through the modulation of GA4 biosynthesis. Finally, the overexpression of SlCDF4 also promoted changes in the profile of carbon and nitrogen compounds related to fruit quality. Overall, our results unveil SlCDF4 as a new key factor controlling tomato size and composition.


Assuntos
Frutas/genética , Giberelinas/metabolismo , Lycopersicon esculentum/genética , Proteínas de Plantas/genética , Proteínas Repressoras/genética , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/metabolismo , Melhoramento Vegetal , Proteínas de Plantas/metabolismo , Proteínas Repressoras/metabolismo , Transdução de Sinais , Regulação para Cima
18.
Int J Food Microbiol ; 332: 108768, 2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-32623289

RESUMO

Soil-borne Salmonella is associated with a large number of food-related disease outbreaks linked to pre-harvest contamination of plants (like tomato) in agricultural fields. Controlling the spread of Salmonella at field is very important in order to prevent various food-borne illnesses. One such approach involves the utilization of antimicrobial secondary metabolite of plant origin. We screened common salad vegetables for anti-Salmonella activity. Beta vulgaris root (beetroot) had very low colonization of Salmonella under in vitro conditions. We hypothesized that beetroot can be used to reclaim the soil contaminated with Salmonella. Cultivation of B. vulgaris in Salmonella treated soil brings down its CFU significantly. Since these antimicrobial effects are non-specific, a co-cultivation system of beet and tomato (a Salmonella susceptible plant) was used to analyze the effect on soil and its microbiota. The soil physicochemical properties and bacterial diversity were unaffected when tomato and beet co-cultivation was used. However, Salmonella burden on the tomato was reduced and its yield was restored. Thus, the inclusion of these crops in the crop-rotation or as a mixed/intercrop or as a bio-control crop can be a fruitful tool to reclaim the Salmonella contaminated soil.


Assuntos
Agricultura/métodos , Beta vulgaris/crescimento & desenvolvimento , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/microbiologia , Salmonella/crescimento & desenvolvimento , Beta vulgaris/metabolismo , Beta vulgaris/microbiologia , Contagem de Colônia Microbiana , Doenças Transmitidas por Alimentos/microbiologia , Doenças Transmitidas por Alimentos/prevenção & controle , Exsudatos de Plantas/farmacologia , Salmonella/efeitos dos fármacos , Microbiologia do Solo
19.
J Environ Sci Health B ; 55(9): 844-853, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32657218

RESUMO

A greenhouse pot experiment was conducted to evaluate the effect of biochar on the growth and uptake of Pb and Zn by tomato plants (Solanum lycopersicum, L.) cultivated in two highly contaminated Kosovo soils, A and B. Plants were cultivated in the biochar amended and unamended soils. As expected, the biochar addition to the two polluted soils has contributed to significantly improve the crop yields, in terms of both fresh and dry weight. Further, results indicated that the effect of biochar on metal mobility is closely related, besides its properties, to soil's native characteristics. In fact, the addition of biochar to soil B had also beneficial effects on the uptake of both metals, halving in some cases the values of the biological accumulation and transfer coefficients, while it did not show the same efficacy on soil A.


Assuntos
Carvão Vegetal , Chumbo/farmacocinética , Lycopersicon esculentum/efeitos dos fármacos , Poluentes do Solo/farmacocinética , Zinco/farmacocinética , Kosovo , Chumbo/análise , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/metabolismo , Poluentes do Solo/análise , Zinco/análise
20.
Chemosphere ; 257: 127252, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32526470

RESUMO

The widespread use of chemical pesticides for crop protection, despite having contributed to ensure food security, have shown to exert negative impacts on the environment and on human health. In addition, the frequent emergence of resistance to pesticides and their adverse effects toward non-target organisms have generated the need to develop novel ecofriendly tools for pest control. Among these, plant essential oils (EOs) may play a central role in arthropod pest control. Recently, two formulations (Emulsion and PEG-nanoparticles) of three citrus EOs (lemon, mandarin and sweet orange) showed a promising potential against Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), a key tomato pest. Here, we evaluated the side effects of these experimental insecticides active substances toward (i) the generalist predator of several tomato pests, Nesidiocoris tenuis Reuter (Hemiptera: Miridae); (ii) the soil enzymatic activities (dehydrogenase activity, alkaline phosphomonoesterase, acid phosphomonoesterase and urease) and (iii) the tomato plant antioxidant enzymes (ascorbate peroxidase, catalase, superoxide dismutase and polyphenol oxidase). Among the tested formulations, mandarin EO-based insecticide presented a significant impact on the predator survival and reproduction. Conversely, all the tested compounds proved to be harmless for the soil enzymatic and the plant antioxidant activities. Overall, these results provide solid bases for the development of novel biopesticides for sustainable tomato crop protection.


Assuntos
Citrus , Óleos Voláteis , Controle Biológico de Vetores/métodos , Animais , Composição de Medicamentos , Heterópteros , Insetos , Inseticidas , Lepidópteros , Lycopersicon esculentum/crescimento & desenvolvimento , Solo
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