Agriculture has a significant environmental impact and is simultaneously called to major challenges, such as responding to the need to develop more sustainable cropping systems with higher productivity. In this context, the present study aimed to obtain lignin nanoparticles (LNs) from pomace, a waste product of the olive oil chain, to be used as a nanobiostimulant in tomato plants. The biostimulant effect of this biopolymer is known, but its reduction to nanometer size can emphasize this property. Tomato plants were subjected to different LN dosages (25, 50, and 100 mg L-1) by foliar application, and inductive effects on photosynthetic machinery, aerial and root biomass production, and root morphology were observed. The treated plants showed increased efficiency in catching and using light, while they reduced the fraction dissipated as heat or potentially toxic to cells for the possibility of creating reactive oxygen species (ROS). Finally, this benefit was matched by increased pigment content and a stimulatory action on the content of nitrogen (NBI) and antioxidant substances such as flavonoids. In conclusion, the present study broadens the horizon of substances with biostimulant action by demonstrating the validity and efficacy of nanobiostimulants obtained from biological residues from the olive oil production chain.

This study aimed to determine the chemical composition of essential oils from A. gratíssima, O. basilicum, S. microphylla, T. riparia, and T. vulgaris and their antioxidant and antifungal activities against Alternaria alternata strains. Gas chromatography-mass spectrometry revealed that the major components of the essential oils were terpenes. The essential oils of S. microphylla and T. riparia showed higher antioxidant activities than the others. The essential oils of S. microphylla and T. riparia inhibited the growth of the fungus at 3.10 and 6.05 µL/mL, respectively. The essential oil of T. riparia inhibited 93.9% of the growth of the fungus and showed the highest in vivo efficiency in severity reduction (76.2%). We conclude that the essential oil of T. riparia shows promising antifungal activity and is an environmentally safe alternative for controlling fungal diseases in vegetables.

UNASSIGNED: Plant growth-promoting bacteria (PGPB) may reduce the negative effects of salinity stress. The aim of this study was to optimize Bacillus megaterium RTS1 and characterize the effect of the PGPB on the physiological characteristics of tomato (Lycopersicon esculentum).
UNASSIGNED: The Central composite design (CCD) of response surface methodology (RSM) was used to optimize Bacillus megaterium RTS1 to produce maximum cell biomass and spores. Then the effect of the PGPB on the physiological characteristics of tomato (Lycopersicon esculentum), including membrane stability, leaf relative water content percentage, anthocyanin and carotenoids content, chlorophyll photosynthetic parameters, sugar and starch level, superoxide anion and antioxidant activity under salt stress conditions. The NFB medium was inoculated with 5% bacterial culture and the fermentation was carried out in a 10-lit fermenter.
UNASSIGNED: After optimization, the amount of cell biomass by the model was 9.45 log10 CFUs/mL, which showed a 1.2-fold increase compared to the non-optimized medium. Usage of bacteria under the optimal conditions of the culture medium may increase the stability of the membrane and improve the relative water content. Bacteria were able to prevent the excessive increase of anthocyanins. Oxidative stress led to an increase in the content of chlorophyll a, while causing the degradation of chlorophyll b. Bacterial inoculation led to an increase in the level of sugar and starch compared to the control. PGPB showed an increasing effect on the amount of superoxide anion production and caused a significant increase in the antioxidant activity under salinity stress conditions.
UNASSIGNED: The PGPB can be a promising way to boost physiological characteristics of tomato plant under salinity stress. Also, sporulation capacity of Bacillus megaterium with high bacterial cell density in fermenter produce a sustainable product for tomato plants.

Tomato pomace, a waste product consisting of peels, seeds, rich on fibrous matter, represents an underutilized source of bioactive compounds, such as polyphenols and carotenoids. Here we present a three-pronged review of the circular utilization of tomato waste in line with the United Nations Sustainable Development Goals. First, we explain why tomato waste is important, highlighting the processing techniques that generate it. The bioactive compounds in these by-products are then comprehensively reviewed, focusing especially on phenolic compounds and carotenoids and the methods used for their extraction. Finally, we examine the potential of these bioactive ingredients for application in food systems and pharmaceutical products.

Bacillus thuringiensis (Bt) is commonly used as a biological control agent (BCA) to control insect pests in edible plant production and can as such be introduced into the food chain of fresh produce. Using standard food diagnostics Bt will be detected and reported as presumptive B. cereus. Tomato plants are often sprayed with Bt biopesticides for insect control, thus these Bt BCAs can also reach the tomato fruits and persist until consumption. In this study, vine tomatoes from the retail in Belgium (Flanders) were investigated for the occurrence and residual numbers of presumptive B. cereus and Bt. Of 109 tomato samples, 61 (56%) were tested positive for presumptive B. cereus. Of the presumptive B. cereus isolates (n = 213) recovered from these samples, 98% were identified as Bt by the production of parasporal crystals. Further quantitative real-time PCR assays on a subselection of Bt isolates (n = 61) showed that 95% of Bt isolates were indistinguishable from Bt biopesticide strains that are approved to be used on crops in the EU. Furthermore, the attachment strength of tested Bt biopesticide strains showed easier wash-off properties if using the commercial Bt granule formulation than the unformulated lab-cultured Bt or B. cereus spore suspensions.

Although sewage water (SW) is a source of nutrients, it also causes heavy metal accumulation in soil; especially, lead (Pb+) contamination of soil is a serious concern in agriculture. Soil contaminants limit the bioavailability of nutrients to plants. So, they affect plant growth and produce quality. Therefore, a pot experiment was conducted to investigate the effect of zeolite soil amendment on the accumulation of Pb+ in tomato crop grown with SW irrigation. The pot media of SW-irrigated plants was amended with different concentrations of zeolite, viz., 0.75%, 1.50%, and 2.25%. The results showed that the application of 0.75% zeolite increased leaf area, plant height, fruit number, and plant fresh and dry biomasses by 37%, 17%, 14%, 24%, and 7% compared to freshwater irrigation. Moreover, the lowest zeolite dose also led to higher chlorophyll content (68.02 SPAD) compared to SW-irrigated plants (55.13 SPAD). Similarly physiological traits, such as A, gs, and E, were higher (17.68 µmol m-2 s-1, gs 0.28 mmol m-2 s-1, and 7.88 mmol m-2 s-1, respectively) in 0.75% zeolite-treated plants than in SW-irrigated plants (12.99 µmol m-2 s -1, 0.19 mmol m-2 s-1, and 7.00 mmol m-2 s -1, respectively). On the contrary, a reduced level of hydrogen peroxide and malondialdehyde and decreased activity of antioxidant enzymes were observed in low-dose zeolite applied plants. Zeolite reduced Pb+ accumulation in tomato plants as compared to SW-irrigated plants, whereby Pb accumulation in the fruits of SW-irrigated plants was 80% more than those of zeolite + SW-treated plants. Conclusively, this study has revealed the improvement in morphological and physiological growth attributes of the SW-irrigated tomato plant in response to zeolite application.

The effect of silicon nanoparticles (1 µg/mL) on the activity of lipid peroxidation, peroxidase, superoxide dismutase, and catalase in tomato roots invaded by root-knot nematode Meloidogyne incognita was studied. It was shown that, at the early stages of parasitization in the plants treated with Si-NPs, a low activity of PO and SOD, as well as an increased level of lipid peroxidation, are observed, which indicates the formation of free radicals (reactive oxygen species, ROS) that can inhibit nematodes and limit the formation of giant cells. During the sedentary stage, at the stages of nutrition, development, and egg production, the roots of the treated plants showed an increased activity of PO, CAT, and SOD, as well as a low activity of LPO as compared to the infested untreated plants. This makes it possible to maintain a balance between the formation and neutralization of ROS and is important not only in the protection of plant tissues from oxidative processes but also in the preservation of giant cells that feed the parasite. The presented data for the first time show the mechanism of action of Si-NPs in the development of resistance and adaptation of plants to biogenic stress, associated with the effect on various components of the antioxidant system and their functional interaction.

HVA22 family proteins with a conserved TB2/DP1/HVA22 domain are ubiquitous in eukaryotes. HVA22 family genes have been identified in a variety of plant species. However, there has been no comprehensive genome-wide analysis of HVA22 family genes in tomato (Solanum lycopersicum L.). Here, we identified 15 non-redundant SlHVA22 genes with three segmentally duplicated gene pairs on 8 of the 12 tomato chromosomes. The predicted three-dimensional (3D) models and gene ontology (GO) annotations of SlHVA22 proteins pointed to their putative transporter activity and ability to bind to diverse ligands. The co-expression of SlHVA22 genes with various genes implicated in multiple metabolic pathways and the localization of SlHVA22-GFP fused proteins to the endoplasmic reticulum suggested that they might have a variety of biological functions, including vesicular transport in stressed cells. Comprehensive expression analysis revealed that SlHVA22 genes were differentially expressed in various organs and in response to abiotic stress conditions. The predominant expression of SlHVA22i at the ripening stage and that of SlHVA22g, SlHVA22k, and SlHVA22l in fruits at most developmental stages suggested their probable involvement in tomato fruit development and ripening. Moreover, the transcript expression of most tomato HVA22 genes, particularly SlHVA22b, SlHVA22i, SlHVA22k, SlHVA22l, SlHVA22m, and SlHVA22n, was affected by abscisic acid (ABA) and diverse abiotic stress treatments, indicating the likely involvement of these genes in tomato abiotic stress responses in an ABA-dependent manner. Overall, our findings provide a foundation to better understand the structures and functional roles of SlHVA22 genes, many of which might be useful to improve the abiotic stress tolerance and fruit quality of tomato through marker-assisted backcrossing or transgenic approaches.

The frequency of waterlogging episodes has increased due to unpredictable and intense rainfalls. However, less is known about waterlogging memory and its interaction with other climate change events, such as elevated CO2 concentration (e[CO2]). This study investigated the combined effects of e[CO2] and two rounds of waterlogging stress on the growth of cultivated tomato (Solanum lycopersicum) and wild tomato (S. pimpinellifolium). The aim is to elucidate the interaction between genotypes and environmental factors and thereby to improve crop resilience to climate change. We found that two rounds of treatments appeared to induce different acclimation strategies of the two tomato genotypes. S. pimpinellifolium responded more negatively to the first-time waterlogging than S. lycopersicum, as indicated by decreased photosynthesis and biomass loss. Nevertheless, the two genotypes respond similarly when waterlogging stress recurred, showing that they could maintain a higher leaf photosynthesis compared to single stress, especially for the wild genotype. This showed that waterlogging priming played a positive role in stress memory in both tomato genotypes. Multivariate analysis showed that waterlogging played a dominant role when combined with [CO2] for both the cultivated and wild tomato genotypes. This work will benefit agricultural production strategies by pinpointing the positive effects of e[CO2] and waterlogging memory.

Hyperkalemia is a major concern in chronic kidney disease and in end-stage renal disease, representing a predictor of hospitalization and mortality. To prevent and treat hyperkalemia, dietary management is of great clinical interest. Currently, the growing use of plant-based diets causes an increasing concern about potassium load in renal patients. The aim of this study was to assess the bioaccessibility of potassium in vegetables, concerning all aspects of the plants (fruit, flower, root, tuber, leaf and seed) and to what extent different boiling techniques affect potassium content and bioaccessibility of plant-based foods. Bioaccessibility was evaluated by an in vitro digestion methodology, resembling human gastro-intestinal tract. Potassium content was higher in seeds and leaves, despite it not being possible to define a common \"rule\" according to the type of organ, namely seed, leaf or fruit. Boiling reduced potassium content in all vegetables excluding carrot, zucchini, and cauliflower; boiling starting from cold water contributed to a greater reduction of the potassium content in potato, peas, and beans. Bioaccessibility after in vitro digestion ranged from 12 (peas) to 93% (tomato) regardless of species and organs. Higher bioaccessibility was found in spinach, chicory, zucchini, tomato, kiwi, and cauliflower, and lower bioaccessibility in peas. Potassium from leaf resulted in the highest bioaccessibility after digestion; as a whole potassium bioaccessibility in the fruits and vegetables studied was 67% on average, with differences in relation to the different organs and species. Further, considering the method of boiling to reduce potassium content, these data indicate that the effective potassium load from plant-based foods may be lower than originally expected. This supports the clinical advices to maintain a wide use of plant-based food in the management of renal patients.