Cucumber mosaic virus, Tomato spotted wilt virus, Tomato mosaic virus, Tomato chlorosis virus, Pepino mosaic virus, Torrado tomato virus and Tomato infectious chlorosis virus cause serious damage and ...significant economic losses in tomato crops worldwide. The early detection of these pathogens is essential for preventing the viruses from spreading and improving their control. In this study, a procedure based on two multiplex RT-PCRs was developed for the sensitive and reliable detection of these seven viruses. Serial dilutions of positive controls were analysed by this methodology, and the results were compared with those obtained by ELISA and singleplex versions of RT-PCR. The multiplex and singleplex RT-PCR assays were able to detect specific targets at the same dilution and were 100 times more sensitive than ELISA. The multiplex versions were able to detect composite samples containing different concentrations of specific targets at ratios from 1:1 to 1:1000. In addition, 45 symptomatic tomato samples collected in different tomato-growing areas of Sicily (Italy) were analysed by multiplex RT-PCR, singleplex RT-PCR and commercially available ELISA tests. Similar results were obtained using the RT-PCR techniques, with a higher sensitivity than ELISA, revealing a common occurrence of mixed infections and confirming the presence of these seven virus species in Italy.
Tomato producing and processing industries present undoubted potential for industrial discarded products valorization whether due to the overproduction of fresh tomatoes or to the loss during ...processing. Although tomato by-products are not yet considered a raw material, several studies have suggested innovative and profitable applications. It is often referred to as "tomato pomace" and is quite rich in a variety of bioactive compounds. Lycopene, vitamin C, β-carotene, phenolic compounds, and tocopherol are some of the bioactives herein discussed. Tomato by-products are also rich in minerals. Many of these compounds are powerful antioxidants with anti-inflammatory properties besides modulating the immune system. Several researchers have focused on the possible application of natural ingredients, especially those extracted from foods, and their physiological and pharmacological effects. Herein, the effects of processing and further applications of the bioactive compounds present in tomato by-products were carefully reviewed, especially regarding the anti-inflammatory and anti-cancer effects. The aim of this review was thus to highlight the existing opportunities to create profitable and innovative applications for tomato by-products in health context.
Plant glandular trichomes are epidermal secretory structures producing various specialized metabolites. These metabolites are involved in plant adaptation to its environment and many of them have ...remarkable properties exploited by fragrance, flavor, and pharmaceutical industries. The identification of genes controlling glandular trichome development is of high interest to understand how plants produce specialized metabolites. Our knowledge about this developmental process is still limited, but genes controlling glandular trichome initiation and morphogenesis have recently been identified. In particular, R2R3-MYB and HD-ZIP IV transcription factors appear to play essential roles in glandular trichome initiation in Artemisia annua and tomato. In this review, we focus on the results obtained in these two species and we propose genetic regulation models integrating these data.
Glandular trichomes are multicellular organs that cover the surface of more than 30% of all land plants. Glandular trichomes synthesize, store, and secrete diverse specialized metabolites.Recent studies have reported genes and protein complexes regulating glandular trichome development in Artemisia annua and tomato. We propose a genetic model to explain the glandular trichome initiation in each species.R2R3-MYB and HD-ZIP IV transcription factor families play essential roles in glandular trichome initiation.Glandular trichome density and size are important factors regulating metabolic content. Increasing glandular trichome density by genetic engineering successfully enhanced specialized metabolite content without any adverse effect on plant growth.
•Biochar application reduced soil bulk density, increased soil porosity and improved soil 3-phase composition.•The interaction between Irrigation quantity and biochar has no obvious effect on the ...soil solid phase.•The application of biochar can improve the yield and quality of tomato under full irrigation and severe water deficit.
Considering the challenges faced by current agricultural industry, such as less cultivable land, lack of soil nutrient value, limited water resources, low yield and fruit quality (Appearance and nutritional values). Biochar application was found effective way to improve soil physical properties, consequently, yield and quality of tomatoes. Biochar at three levels: B0 (0 ton/ha), B1 (25 tons/ha) and B2 (50 tons/ha) with three levels of drip irrigation quantity: full irrigation T1 (1.4 pan evaporation Ep), moderate water deficit T2 (1.2 Ep) and severe water deficit T3 (1.0 Ep) were applied in greenhouse. Thus, nine treatments, i.e. T1B0, T1B1, T1B2, T2B0, T2B1, T2B2, T3B0, T3B1 and T3B2 were set. The effects of applied different levels of irrigation quantity and biochar on soil physical properties, crop growth, yield and fruit quality were observed. Increasing level of applied irrigation quantity and biochar could improve the physical properties of soil effectively: decreased, increased and varied the soil bulk density, porosity and 3-phase composition of soil respectively. It is found that increasing levels of applied irrigation quantity at B2 had good effects on bulk density, porosity and 3-phase proportion of soil, and best composition of 3-phase (solid and pores: liquid + gas were 33.68 % and 66.32 % respectively) at T2B2 was found. The growth rate, considering growth parameters: plant height and stem diameter, was increased by applying adequate level of irrigation quantity and biochar. The yield was found maximum at T1B2, which was increased by 30.92 % as compared to T1B0. For T3 level, biochar application increased tomato yield, as compared to B0 by 83.69 % and 176.60 % at B1 and B2 respectively. It is concluded that application of biochar under full and severe deficit irrigation level increased tomato yield effectively, but tomato growth could inhibit under moderate water deficit irrigation, caused a slight yield reduction.
Tomato is one of the most often cultivated vegetable species worldwide. Due to the anti-oxidative and anti-cancer properties of lycopene, tomato consumption as well as production is still increasing. ...However, its productivity is impaired by a wide range of abiotic stresses, and the establishment of stress-tolerant crops is a key challenge for agricultural biotechnology. Until now, a few genetic approaches have been used to achieve stress tolerance in cultivated tomato plants. Such achievements are based on current knowledge concerning plant adaptation. The presence of adverse environmental factors like extreme temperatures, salinity or drought cause definite biochemical and physiological consequences. Mostly, these are the changes in the metabolic pathways, the expression of stress-inducible genes or the accumulation of low-molecular compounds that play a crucial role in maintaining the plasticity of reactions. The biotechnological methods used to modify tomato to produce “upgraded” plants are based on introgression of several genes coding enzymes known to mitigate stress or genes contributing to signalling and diverse regulatory pathways. Here, we present an overview of the most often chosen target sequences/molecules that are genetically delivered or engineered to obtain tolerance to environmental constraints. Since adverse conditions cause interrelated stress responses, it is the tolerance molecular players that are consecutively presented in this paper rather than the typically reviewed division of stress types.
•A deep learning model based on attention mechanism is proposed for tomato virus disease recognition.•The recognition accuracy is improved while maintaining the same detection speed.•It provides ...technical support for other researches related to plant disease recognition.
Traditional target detection methods cannot effectively screen key features, which leads to overfitting and produces a model with a weak generalization ability. In this paper, an improved SE-YOLOv5 network model is proposed for the recognition of tomato virus diseases. Images of tomato diseases in greenhouses were collected using a mobile phone, and the collected images were expanded. A squeeze-and-excitation (SE) module was added to a YOLOv5 model to realize the extraction of key features, using a human visual attention mechanism for reference. The trained network model was evaluated on the test set of tomato virus diseases. The accuracy was 91.07%, which was 7.12%, 17.85% and 8.91% higher than that of the Faster regions with convolutional neural network features (R-CNN) model, single-shot multiBox detector (SSD) model and YOLOv5 model, respectively. Meanwhile, the mean average precision (mAP@0.5) was 94.10%, which was 1.23%, 16.77% and 1.78% higher than that of the Faster R-CNN model, SSD model and YOLOv5 model. The proposed SE-YOLOv5 model can effectively detect regions of tomato virus disease, which provides disease identification and control theoretical research and technical support.
AbstractTomatoes are popular worldwide and represent a high water-dependent horticultural crop cultivated both in open fields and greenhouses. Several irrigation management strategies are currently ...practiced in greenhouse tomato production. Among them, deficit irrigation has been generally applied in areas where access to fresh water is difficult or expensive. The overall objective of this review is to synthesize studies related to deficit irrigation for greenhouse tomato cultivation and to explore its strengths, limitations, and potential and future outlook. The effects of deficit irrigation on water productivity, yields, and crop quality parameters when planted in different soil types using different cultivars were reviewed. We infer that deficit irrigation can result in decreased tomato yields and improved water productivity and crop quality parameters at defined levels of irrigation deficiency. The effects of deficit irrigation on tomato yield, water productivity, and crop quality were found to be cultivar specific. Furthermore, the same cultivar, when subjected to different deficit irrigation techniques, demonstrates different yield and quality responses.
Tospoviruses cause significant losses to a wide range of agronomic and horticultural crops worldwide. The type member,
(TSWV), causes systemic infection in susceptible tomato cultivars, whereas its ...infection is localized in cultivars carrying the
5 resistance gene. The response to TSWV infection in tomato cultivars with or without
-5 was determined at the virus small RNA level in the locally infected leaf. Predicted reads were aligned to TSWV reference sequences. The TSWV genome was found to be differentially processed among each of the three-viral genomic RNAs-Large (L), Medium (M) and Small (S)-in the
-5(+) compared to
-5(-) genotypes. In the
-5(+) cultivar, the L RNA had the highest number of viral small-interfering RNAs (vsiRNAs), whereas in the
-5(-) cultivar the number was higher in the S RNA. Among the three-viral genomic RNAs, the distribution of hotspots showed a higher number of reads per million reads of vsiRNAs of 21 and 22 nt class at the 5' and 3' ends of the L and the S RNAs, with less coverage in the M RNA. In the
-5(-) cultivar, the nature of the 5' nucleotide-end in the siRNAs varied significantly; reads with 5'-adenine-end were most abundant in the mock control, whereas cytosine and uracil were more abundant in the infected plants. No such differences were seen in case of the resistant genotype. Findings provided insights into the response of tomato cultivars to TSWV infection.
• Analysis of the updated reference tomato genome found 34 full-length TPS genes and 18 TPS pseudogenes.
• Biochemical analysis has now identified the catalytic activities of all enzymes encoded by ...the 34 TPS genes: one isoprene synthase, 10 exclusively or predominantly monoterpene synthases, 17 sesquiterpene synthases and six diterpene synthases. Among the monoterpene and sesquiterpene and diterpene synthases, some use trans-prenyl diphosphates, some use cis-prenyl diphosphates and some use both. The isoprene synthase is cytosolic; six monoterpene synthases are plastidic, and four are cytosolic; the sesquiterpene synthases are almost all cytosolic, with the exception of one found in the mitochondria; and three diterpene synthases are found in the plastids, one in the cytosol and two in the mitochondria.
• New trans-prenyltransferases (TPTs) were characterised; together with previously characterised TPTs and cis-prenyltransferases (CPTs), tomato plants can make all cis and trans C10, C15 and C20 prenyl diphosphates. Every type of plant tissue examined expresses some TPS genes and some TPTs and CPTs.
• Phylogenetic comparison of the TPS genes from tomato and Arabidopsis shows expansions in each clade of the TPS gene family in each lineage (and inferred losses), accompanied by changes in subcellular localisations and substrate specificities.
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