The tomato processing industry strives to maximize product yield, keep energy costs and waste effluents to a minimum while maintaining high product quality. Pulsed Electric Field (PEF) processing ...increases plant cell permeability through electroporation and could be applied in tomato processing to facilitate peeling, increase juice yields and enhance valorization of tomato waste. PEF was applied to three different steps, of industrial tomato processing. In the first step, different PEF treatments (0.5–1.5 kV/cm, 0–8000 pulses, 15 μs pulse width) applied to whole tomatoes improved peeling, reducing the work required for peel detachment up to 72.3%. In the second step, PEF (0.5–2.5 kV/cm, 0–4000, pulses, 15 μs pulse width) applied to chopped tomatoes, increased tomato juice yield up to 20.5%. PEF was also applied to the residues of the first juicing step comprising seeds, peels and a fraction of tomato flesh, to further increase juice yield with the overall yield reaching 90.2%. In the third step the effects of PEF on the extraction of high added value compounds from juicing residues were studied. Carotenoid extraction yield increased up to 56.4%. Lycopene extraction increased from 9.84 mg lycopene/100 g to 14.31 mg/100 g tomato residue for a PEF treatment at 1.0 kV/cm for 7.5 ms. The concentration of extracted total phenolic compounds doubled (56.16 mg gallic acid/kg) with a 2 kV/cm, 700 pulses treatment. The increased antioxidant capacity was correlated to carotenoid concentration. Overall, targeted PEF pretreatments incorporated to industrial tomato processing lead to decreased energy demand and increased productivity.
•PEF treatment led to decreased peel detachment work by 72.3%, without deteriorating the final firmness of the tomatoes.•The highest tomato juice yield achieved was 20.5% higher compared to untreated sample after PEF processing.•PEF at 5 kV/cm improved the carotenoid extraction (14.31 mg lycopene/100 g tomato waste) by 56.4%.•The extraction of phenolic compounds doubled (56.16 mg GA/kg) for PEF conditions 2 kV/cm and 700 pulses from tomato waste.•Cell disintegration index is a reliable measure which can be correlated with all aspects studied in the present work.
Resistances to begomoviruses, including bipartite tomato mottle virus and monopartite tomato yellow leaf curl virus (TYLCV), have been introgressed to cultivated tomato (
Solanum lycopersicum
) from ...wild tomato accessions. A major gene,
Ty
-
2
from
S. habrochaites
f.
glabratum
accession “B6013
,”
that confers resistance to TYLCV was previously mapped to a 19-cM region on the long arm of chromosome 11. In the present study, approximately 11,000 plants were screened and nearly 157 recombination events were identified between the flanking markers C2_At1g07960 (82.5 cM, physical distance 51.387 Mb) and T0302 (89 cM, 51.878 Mb). Molecular marker analysis of recombinants and TYLCV evaluation of progeny from these recombinants localized
Ty
-
2
to an approximately 300,000-bp interval between markers UP8 (51.344 Mb) and M1 (51.645 Mb). No recombinants were identified between TG36 and C2_At3g52090, a region of at least 115 kb, indicating severe recombination suppression in this region. Due to the small interval, fluorescence in situ hybridization analysis failed to clarify whether recombination suppression is caused by chromosomal rearrangements. Candidate genes predicted based on tomato genome annotation were analyzed by RT-PCR and virus-induced gene silencing. Results indicate that the NBS gene family present in the
Ty
-
2
region is likely not responsible for the
Ty
-
2
-conferred resistance and that two candidate genes might play a role in the
Ty
-
2
-conferred resistance. Several markers very tightly linked to the
Ty
-
2
locus are presented and useful for marker-assisted selection in breeding programs to introgress
Ty
-
2
for begomovirus resistance.
Tomato yellow leaf curl disease (TYLCD) is one of the most devastating viral diseases affecting tomato crops in tropical, subtropical and temperate regions of the world. Here, we focus on the ...interactions through recombination between the different begomovirus species causing TYLCD, provide an overview of the interactions with the cellular genes involved in viral replication, and highlight recent progress on the relationships between these viruses and their vector, the whitefly Bemisia tabaci. The tomato yellow leaf curl virus-like viruses (TYLCVs) are a complex of begomoviruses (family Geminiviridae, genus Begomovirus) including 10 accepted species: Tomato yellow leaf curl Axarquia virus (TYLCAxV), Tomato yellow leaf curl China virus (TYLCCNV), Tomato yellow leaf curl Guangdong virus (TYLCGuV), Tomato yellow leaf curl Indonesia virus (TYLCIDV), Tomato yellow leaf curl Kanchanaburi virus (TYLVKaV), Tomato yellow leaf curl Malaga virus (TYLCMalV), Tomato yellow leaf curl Mali virus (TYLCMLV), Tomato yellow leaf curl Sardinia virus (TYLCSV), Tomato yellow leaf curl Thailand virus (TYLCTHV), Tomato yellow leaf curl Vietnam virus (TYLCVNV) and Tomato yellow leaf curl virus(TYLCV). We follow the species demarcation criteria of the International Committee on Taxonomy of Viruses (ICTV), the most important of which is an 89% nucleotide identity threshold between full-length DNA-A component nucleotide sequences for begomovirus species. Strains of a species are defined by a 93% nucleotide identity threshold. The primary host of TYLCVs is tomato (Solanum lycopersicum), but they can also naturally infect other crops common bean (Phaseolus vulgaris), sweet pepper (Capsicum annuum), chilli pepper (C. chinense) and tobacco (Nicotiana tabacum), a number of ornamentals petunia (Petuniaxhybrida) and lisianthus (Eustoma grandiflora), as well as common weeds (Solanum nigrum and Datura stramonium). TYLCVs also infect the experimental host Nicotiana benthamiana. Infected tomato plants are stunted or dwarfed, with leaflets rolled upwards and inwards; young leaves are slightly chlorotic; in recently infected plants, fruits might not be produced or, if produced, are small and unmarketable. In common bean, some TYLCVs produce the bean leaf crumple disease, with thickening, epinasty, crumpling, blade reduction and upward curling of leaves, as well as abnormal shoot proliferation and internode reduction; the very small leaves result in a bushy appearance.
In plants, regulated intramembrane proteolysis (RIP) is crucial for proper growth, development, and stress management. Rhomboid proteases (RPs) residing in the membrane play a vital role in ...orchestrating RIP. Although RPs can be found in most sequenced genomes, tomato rhomboids (SlRPs) have not yet been studied. Using alternative and comprehensive strategies, we found ten SlRPs encoded in the tomato genome. These SlRPs possess signature motifs and transmembrane domains, showing structural similarity to other members of the RP family. Also, SlRPs are genetically related to other known RPs of the Solanaceae family. Seven of the SlRPs retain serine-histidine catalytic dyads, making them proteolytically active, while three iRhoms lack the dyad and other structural motifs. Although SlRPs could have functional redundancy, their distribution and expression pattern indicate tissue specificity and responsiveness to specific external stimuli. The presence of development and stress-response-related cis-elements in the promoters of SlRPs supports this view. Furthermore, our strategically designed substrate-reporter assay shows that SlRPs have proteolytic activity similar to that of known RPs. This study provides a detailed understanding of all SlRPs and their physico-chemical features, shedding light on their involvement in physiological processes.
•Tomato genome harbors 10 Rhomboid Intramembrane proteases (SlRPs).•Most of SlRPs possess 7 TMDs (Transmembrane Domains).•SlRPs gets differentially regulated upon exposure to various stress conditions.•SlRPs can cleave known RP substrates.
CRISPR/Cas systems confer molecular immunity against phages and conjugative plasmids in prokaryotes. Recently, CRISPR/Cas9 systems have been used to confer interference against eukaryotic viruses. ...Here, we engineered Nicotiana benthamiana and tomato (Solanum lycopersicum) plants with the CRISPR/Cas9 system to confer immunity against the Tomato yellow leaf curl virus (TYLCV). Targeting the TYLCV genome with Cas9-single guide RNA at the sequences encoding the coat protein (CP) or replicase (Rep) resulted in efficient virus interference, as evidenced by low accumulation of the TYLCV DNA genome in the transgenic plants. The CRISPR/Cas9-based immunity remained active across multiple generations in the N. benthamiana and tomato plants. Together, our results confirmed the efficiency of the CRISPR/Cas9 system for stable engineering of TYLCV resistance in N. benthamiana and tomato, and opens the possibilities of engineering virus resistance against single and multiple infectious viruses in other crops.
expanded tomato fruit volatile landscape Rambla, José L; Tikunov, Yury M; Monforte, Antonio J ...
Journal of experimental botany,
08/2014, Letnik:
65, Številka:
16
Journal Article
Recenzirano
Odprti dostop
A tomato fruit volatile review is presented which addresses updated biosynthesis pathways, control of emission by conjugation and hydrolysis, and discussion about the difficulties in and ...opportunities for breeding better tasting tomatoes.
Research has suggested that lycopene may be metabolized by eccentric cleavage, catalyzed by β-carotene oxygenase 2, resulting in the generation of apo-lycopenals. Apo-6′-lycopenal and ...apo-8′-lycopenal have been reported previously in raw tomato. We now show that several other apo-lycopenals are also present in raw and processed foods, as well as in human plasma. Apo-lycopenal standards were prepared by in vitro oxidation of lycopene, and a high-performance liquid chromatography−tandem mass spectrometry (HPLC-MS/MS) method using atmospheric pressure chemical ionization in negative mode was developed to separate and detect the apo-6′-, apo-8′-, apo-10′-, apo-12′-, apo-14′-, and apo-15′-lycopenal products formed in the reaction. Hexane/acetone extracts of raw tomato, red grapefruit, watermelon, and processed tomato products were analyzed, as well as plasma of individuals who had consumed tomato juice for 8 weeks. Apo-6′-, apo-8′-, apo-10′-, apo-12′-, and apo-14′-lycopenals were detected and quantified in all food products tested, as well as plasma. The sum of apo-lycopenals was 6.5 μg/100 g Roma tomato, 73.4 μg/100 g tomato paste, and 1.9 nmol/L plasma. We conclude that several apo-lycopenals, in addition to apo-6′- and -8′-lycopenal, are present in lycopene-containing foods. In addition, the presence of apo-lycopenals in plasma may derive from the absorption of apo-lycopenals directly from food and/or human metabolism.
Tomato brown rugose fruit virus (ToBRFV) is an emerging and rapidly spreading RNA virus that infects tomato and pepper, with tomato as the primary host. The virus causes severe crop losses and ...threatens tomato production worldwide. ToBRFV was discovered in greenhouse tomato plants grown in Jordan in spring 2015 and its first outbreak was traced back to 2014 in Israel. To date, the virus has been reported in at least 35 countries across four continents in the world. ToBRFV is transmitted mainly via contaminated seeds and mechanical contact (such as through standard horticultural practices). Given the global nature of the seed production and distribution chain, and ToBRFV's seed transmissibility, the extent of its spread is probably more severe than has been disclosed. ToBRFV can break down genetic resistance to tobamoviruses conferred by R genes Tm‐1, Tm‐2, and Tm‐22 in tomato and L1 and L2 alleles in pepper. Currently, no commercial ToBRFV‐resistant tomato cultivars are available. Integrated pest management‐based measures such as rotation, eradication of infected plants, disinfection of seeds, and chemical treatment of contaminated greenhouses have achieved very limited success. The generation and application of attenuated variants may be a fast and effective approach to protect greenhouse tomato against ToBRFV. Long‐term sustainable control will rely on the development of novel genetic resistance and resistant cultivars, which represents the most effective and environment‐friendly strategy for pathogen control.
Taxonomy
Tomato brown rugose fruit virus belongs to the genus Tobamovirus, in the family Virgaviridae. The genus also includes several economically important viruses such as Tobacco mosaic virus and Tomato mosaic virus.
Genome and virion
The ToBRFV genome is a single‐stranded, positive‐sense RNA of approximately 6.4 kb, encoding four open reading frames. The viral genomic RNA is encapsidated into virions that are rod‐shaped and about 300 nm long and 18 nm in diameter. Tobamovirus virions are considered extremely stable and can survive in plant debris or on seed surfaces for long periods of time.
Disease symptoms
Leaves, particularly young leaves, of tomato plants infected by ToBRFV exhibit mild to severe mosaic symptoms with dark green bulges, narrowness, and deformation. The peduncles and calyces often become necrotic and fail to produce fruit. Yellow blotches, brown or black spots, and rugose wrinkles appear on tomato fruits. In pepper plants, ToBRFV infection results in puckering and yellow mottling on leaves with stunted growth of young seedlings and small yellow to brown rugose dots and necrotic blotches on fruits.
This pathogen profile summarizes current knowledge about ToBRFV, highlights recent research progress, discusses future research directions, and proposes short‐run and long‐term control strategies.
SUMMARY
With the development of high‐throughput sequencing, many long non‐coding RNAs (lncRNAs) have been found to play important roles in diverse biological processes. However, the biological ...functions of most plant lncRNAs are still unknown. We have previously discovered a tomato ripening‐related lncRNA, lncRNA1459. Here, we cloned the full‐length lncRNA1459, giving two transcript isoforms. In addition, lncRNA1459 exhibited a specific location in the nucleus. Furthermore, in order to fully identify the function of lncRNA1459 in tomato ripening, loss‐of‐function mutants of lncRNA1459 were developed using clustered regularly interspaced short palindromic repeats (CRISPR)/‐associated protein 9 (Cas9)‐induced genome editing technology. Compared with wild‐type fruits, the tomato ripening process was significantly repressed in lncRNA1459 mutants. Ethylene production and lycopene accumulation were largely repressed in lncRNA1459 mutants. Additionally, genes related to ethylene and carotenoid biosynthesis were distinctly downregulated in lncRNA1459 mutants compared with wild‐type fruits. Moreover, expression of numerous ripening‐related genes was changed significantly when lncRNA1459 was knocked out. Expression of potential tomato ripening‐related lncRNAs was also specifically changed after knocking out lncRNA1459. Taken together, these results provide insight into the role of lncRNA1459 in tomato fruit ripening.
Significance Statement
In this work the full length of lncRNA1459 was cloned and the subcellular location of lncRNA1459 was verified. Furthermore, CRISPR/Cas9 was used to knock out lncRNA1459, indicating a relationship between lncRNA1459 and tomato fruit ripening.
Finding thresholds at which loss of plant functionality occurs during drought is critical for predicting future crop productivity and survival. Xylem resistance to embolism has been suggested as a ...key trait associated with water-stress tolerance. Although a substantial literature exists describing the vulnerability of woody stems to embolism, leaves and roots of herbaceous species remain under-represented. Also, little is known about vulnerability to embolism at a whole-plant scale or propagation of embolism within plants.
New techniques to view the process of embolism formation provide opportunities to resolve long-standing questions. Here, we used multiple visual techniques, including X-ray microcomputed tomography and the optical vulnerability method, to investigate the spread of embolism within intact stems, leaves and roots of Solanum lycopersicum (common tomato).
We found that roots, stems and leaves of tomato plants all exhibited similar vulnerability to embolism, suggesting that embolism rapidly propagates among tissues. Although we found scarce evidence for differentiation of xylem vulnerability among tissues at the scale of the whole plant, within a leaf the midrib embolized at higher water potentials than lower order veins.
Substantial overlap between the onset of cavitation and incipient leaf damage suggests that cavitation represents a substantial damage to plants, but the point of lethal cavitation in this herbaceous species remains uncertain.
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