•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.
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.
Eggplant is one of the important vegetable crops grown across the world, and its production is threatened by both biotic and abiotic stresses. Diseases caused by viruses are becoming major limiting ...factors for its successful cultivation. A survey for begomovirus-like symptoms in 72 eggplant fields located in six different Indian states revealed a prevalence of disease ranging from 5.2 to 40.2%, and the symptoms recorded were mosaic, mottling, petiole bending, yellowing, and upward curling, vein thickening, and enation of the leaves, and stunting of plants. The causal agent associated with these plants was transmitted from infected leaf samples to healthy eggplant seedlings via grafting and whiteflies (Bemisia tabaci). The presence of begomovirus was confirmed in 72 infected eggplant samples collected from the surveyed fields exhibiting leaf curl and mosaic disease by PCR using begomovirus specifc primers (DNA-A componet), which resulted in an expected amplicon of 1.2 kb. The partial genome sequence obtained from amplified 1.2 kb from all samples indicated that they are closely related begomovirus species, tomato leaf Karnataka virus (ToLCKV, two samples), tomato leaf curl Palampur virus (ToLCPalV, fifty eggplant samples), and chilli leaf curl virus (ChLCuV, twenty samples). Based on the partial genome sequence analysis, fourteen representative samples were selected for full viral genome amplification by the rolling circle DNA amplification (RCA) technique. Analyses of fourteen eggplant isolates genome sequences using the Sequence Demarcation Tool (SDT) indicated that one isolate had the maximum nucleotide (nt) identity with ToLCKV and eight isolates with ToLCPalV. Whereas, four isolates four isolates (BLC1-CH, BLC2-CH, BLC3-CH, BLC4-CH) are showing nucleotide identity of less than 91% with chilli infecting viruses begomoviruses with chilli infecting begomoviruses and as per the guidelines given by the ICTV study group for the classification of begomoviruses these isolates are considered as one novel begomovirus species, for which name, Eggplant leaf curl Chhattisgarh virus (EgLCuChV) is proposed. For DNA-B component, seven eggplant isolates had the highest nt identity with ToLCPalV infecting other crops. Further, DNA satellites sequence analysis indicated that four betasatellites identified shared maximum nucleotide identity with the tomato leaf curl betasatellite and five alphasatellites shared maximum nucleotide identity with the ageratum enation alphasatellite. Recombination and GC plot analyses indicated that the bulk of begomovirus genome and associated satellites presumably originated from of previously known mono and bipartite begomoviruses and DNA satellites. To the best of our knowledge, this is India's first report of ToLCKV and a noval virus, eggplant leaf curl Chhattisgarh virus associated with eggplant leaf curl disease.
•Eggplant is one of important vegetable crop and its production is threatened by a number of biotic and abiotic stresses.•Total 72 viral infected eggplant plant samples showing mosaic and leaf curl disease were collected from six different Indian state were characterised.•Both mono and bipartite begomoviruses are associated eggplant mosaic and leaf curl disease.•Four different types betasatellites and five alphasatellites were mosaic and leaf curl disease of eggplant in India.•Recombination and GC plot analysis revealed that recombination occurred in low GC content regions of viral genomes (DNA A and DNA B components) and DNA satellites.•This is the first report of ToLCKV and a new Chhattisgarh begomovirus linked to eggplant leaf curl disease.
Tomatoes are among the most consumed vegetables worldwide and represent a source of health-beneficial substances. Our study represents the first investigating the peel-associated epiphytic bacteria ...of red and purple (anthocyanin-rich) tomatoes subjected to organic and conventional farming systems. Proteobacteria was the dominant phylum (relative abundances 79–91%) in all experimental conditions. Enterobacteriaceae represented a large fraction (39.3–47.5%) of the communities, with Buttiauxella and Atlantibacter as the most represented genera. The core microbiota was composed of 59 operational taxonomic units (OTUs), including the majority of the most abundant ones. The occurrence of the most abundant OTUs differed among the experimental conditions. OTU 1 (Buttiauxella), OTU 2 (Enterobacteriales), and OTU 6 (Bacillales) were higher in red and purple tomatoes grown under organic farming. OTU 5 (Acinetobacter) had the highest abundance in red tomatoes subjected to organic farming. OTU 3 (Atlantibacter) was among the major OTUs in red tomatoes under both farming conditions. OTU 7 (Clavibacter) and OTU 8 (Enterobacteriaceae) had abundances ≥1% only in red tomatoes grown under conventional farming. PCA and clustering analysis highlighted a high similarity between the bacterial communities of red and purple tomatoes grown under organic farming. Furthermore, the bacterial communities of purple tomatoes grown under organic farming showed the lowest diversity and evenness. This work paves the way to understand the role of nutritional superior tomato genotypes, combined with organic farming, to modulate the presence of beneficial/harmful bacteria and supply healthier foods within a sustainable agriculture.
The environmental impact of imported fresh agricultural products, such as off-season vegetables transported over long distances, is under growing scrutiny. We hypothesised that the environmental Life ...Cycle Assessment (LCA) ranking between local and imported vegetables might change depending on the impact category considered. We focused on the case study of off-season tomatoes produced in Morocco under unheated greenhouses in a water-scarce area, which covers 68% of the fresh tomatoes imported to France. First, we performed a cradle-to-market gate LCA of the Moroccan production using primary data based on a field survey. Second, we applied the same Life Cycle Impact Assessment (LCIA) method to published cradle-to-farm-gate results of the French tomato cropping system, which also provides off-season tomatoes to the French market and which is characterised by heated greenhouses with a high level of inputs. In addition to typical environmental impact categories, the freshwater use impact was included. The ranking between imported and local tomatoes was different depending on the impact category. Freshwater use had greater impacts under the Moroccan arid climate: 28.0 L H2Oeq kg−1 of Moroccan tomato and 7.5 L H2Oeq kg−1 of French tomato. Conversely, the higher level of artificialisation of the French production resulted in greater impacts on total energy consumption, global warming, and eutrophication, even including transport to France for the Moroccan tomato. This reveals a trade-off between freshwater use impacts and the usual/other impacts, mostly energy-related. At the farm gate, we found that the Moroccan tomato water consumption highly contributed to the total damages to Human Health (14%), and Ecosystems (20%) (contribution to Resources depletion was only 2%). Therefore, ignoring the impacts of freshwater use in LCA also underestimates the damages. Moreover, we showed that the assessment of freshwater use impacts and damages still has shortcomings, leading to an underestimation of the impact for the Moroccan tomato case. These results emphasised the importance of considering all of the impact categories when performing an agricultural LCA and the need for a more comprehensive method for assessing the impacts of freshwater use. In particular, the use of an operational tool for estimating water and solute fluxes at the field level is recommended to feed freshwater impact assessment methods.
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•LCA of fresh tomato production in water scarce southwest Morocco was performed.•Moroccan imported and French locally produced off-season fresh tomato are compared.•From a freshwater resource perspective, French local production performs better.•From a carbon and energy perspective, Moroccan imported production performs better.•Methodological development is needed for a comprehensive water use impact assessment.
RNA interference (RNAi), a conserved RNA‐mediated gene regulatory mechanism in eukaryotes, plays an important role in plant growth and development, and as an antiviral defence system in plants. As a ...counter‐strategy, plant viruses encode RNAi suppressors to suppress the RNAi pathways and consequently down‐regulate plant defence. In geminiviruses, the proteins AC2, AC4 and AV2 are known to act as RNAi suppressors. In this study, we have designed a gene silencing vector using the features of trans‐acting small interfering RNA (tasiRNA), which is simple and can be used to target multiple genes at a time employing a single‐step cloning procedure. This vector was used to target two RNAi suppressor proteins (AC2 and AC4) of the geminivirus, Tomato leaf curl New Delhi virus (ToLCNDV). The vector containing fragments of ToLCNDV AC2 and AC4 genes, on agro‐infiltration, produced copious quantities of AC2 and AC4 specific siRNA in both tobacco and tomato plants. On challenge inoculation of the agro‐infiltrated plants with ToLCNDV, most plants showed an absence of symptoms and low accumulation of viral DNA. Transgenic tobacco plants were raised using the AC2 and AC4 tasiRNA‐generating constructs, and T₁ plants, obtained from the primary transgenic plants, were tested for resistance separately against ToLCNDV and Tomato leaf curl Gujarat virus. Most plants showed an absence of symptoms and low accumulation of the corresponding viruses, the resistance being generally proportional to the amounts of siRNA produced against AC2 and AC4 genes. This is the first report of the use of artificial tasiRNA to generate resistance against an important plant virus.
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