Appropriate soil conditions are important for the success of culturing tomatoes. In fact, there are mineral elements that are essential for the good and healthy development of tomatoes, namely, ...nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, iron, and zinc. Additionally, organic matter and pH play important parts in the process. In this context, this study aimed to characterize a soil destined to produce an industrial tomato variety in South Portugal. As such, mineral elements content, pH, electrical conductivity, humidity, organic matter, and color (without humidity and without humidity and organic matter) were analyzed in 16 soil samples before any type of soil preparation was carried out. Through principal components analysis (PCA), it was possible to observe that electrical conductivity and humidity are more correlated with each other than pH and organic matter. However, the pH of soil varied between 6.9 (minimum) and 7.3 (maximum): in accordance with the ideal range values for tomato production. Additionally, regarding quantification of mineral elements, Fe showed a higher content, followed by K, Ca, P, Mg, S, Zn, and As. However, regarding the color of the soil without humidity and without humidity and organic matter, there were significant differences between CieLab parameters (L, Chroma, and Hue). Nevertheless, soil conditions of the field presented good requirements for tomato production, despite the higher levels of Fe in the soil and the presence of As.
Meloidogyne incognita root-knot nematode is one of the main causes of tomato root damage and consequently crop production losses. Thus, in in vitro conditions, the number of nematodes hatched eggs ...(%) at 4 and 6 days and nematode mortality (J2 stage) at 8, 18, and 24 h, were evaluated in Petri dishes containing the candidate rhizobacteria Enterobacter asburiae (BA4-19 and PM3-14), Acinetobacter calcoaceticus (BM2-12), Klebsiella variicola (BO3-4) and Serratia marcescens (PM3-8). The well-known Pseudomonas protegens (CHA0) and P. veronii (R4) were used as controls. In greenhouse conditions, plant height, root weight, and symptoms, as well as gall and nematode numbers, were determined in tomato plants infected by M. incognita and treated with the seven rhizobacteria. In addition, all variables were correlated using Pearson's analysis. In general, a significant correlation was observed among the variables of both experiments, showing the antagonistic capacity of the strains against nematode. It seems, that PM3-8 and PM3-14 strains reduce hatching, and cause mortality of nematodes J2 if compared with CHA0 and R4 strains. Likewise, tomato treated with BM2-12 strain shows a higher height and root weight, as well as a smaller number of galls and nematodes in their roots. This study provides evidence that PM3-8 and PM3-14 strains reduce the M. incognita egg hatching, and that the BM2-12 strain can be a plant growth-promoter potential of tomato plants.
Tembotrione is a herbicide belonging to the triketone group, which is commonly used for postemergence weed control in maize fields. However, its application can have unintended effects on plants ...growing on neighboring land, due to factors such as spray drift, carryover, and residue in soils. These off-target effects can potentially cause harm to non-target plants and ecosystems. Off-target application of tembotrione to tomato plants can result in negative effects such as various patterns of chlorosis and reduction in growth, yield, and quality. These effects can adversely impact tomato plants and their ability to produce healthy fruit. Field trials were conducted to explain the negative effects of tembotrione on tomato plants at a rate of 20% of the recommended dose specified on the label. Several growth parameters were measured during the trial to assess the impact of tembotrione on tomato plants: fresh and dry biomass of plants (g), leaf area (cm
2
), yield (kg plot
−1
), fruit length (cm), fruit diameter (cm), titrable acidity (%), soluble solid content (%), and pH. According to the results obtained, tembotrione negatively affected tomato plants. The applied dose of tembotrione mostly had a negative effect on the quality of both the tomato foliage and fruits. However, despite this negative effect, there was no statistically significant impact on the yield. In fact, the yield slightly increased as a result of tembotrione treatment. On the other hand, use of tembotrione caused a decrease in the marketable yield of tomatoes due to a reduction in the visual quality of the fruits. Additionally, the tembotrione drift simulation treatment resulted in an increase of approximately 17.5% in titrable acidity (TA).
Eight different Serbian genotypes were analysed for their polyphenol, carotenoid, vitamin C content and evaluated for their antioxidant properties. The highest content of biologically important ...carotenoids such as lutein (4.58 mg/10 g), lycopene (160.64 mg/10 g) and β-carotene (189.64 mg/10 g) were detected in the genotype S606. Rutin was the most abundant phenolic compound in all tastes samples, but its content is highest in the genotype S615 (1424.30 µg/100 g dw). All tomato samples were the great source of vitamin C, where the sample S615 stood out (68.54 mg AA g
−1
of dw). Their content of antioxidant compounds suggested that genotypes S606 and S615 showed the best antioxidant potential. Principal component analysis (PCA) and Partial least squares (PLS) were applied to analyse results. The results obtained in the present study could be of considerable interest for breeding programmes wishing to select tomato genotypes with high biological and nutritional properties.
Fruit yield and quality of greenhouse tomatoes are strongly influenced by light conditions and nitrogen (N) availability, however, the interaction between these factors is still unclear. We evaluated ...the effects on cherry tomatoes of two tunnel plastic covers with different optical properties and three N doses, also in combination with a biostimulant treatment. We compared a diffuse light film (Film1) and a conventional clear film (Film2), and three N levels, corresponding to 50% (N50), 75% (N75) and 100% (N100) of the optimal dose, with and without a microbial plus a protein hydrolysed biostimulant, compared to a non-treated control. The three experimental treatments significantly interacted on several yield and quality parameters. In control plants (untreated with biostimulants), the early yield was higher at reduced N doses compared to N100, with greater increments under the diffusive Film1 compared to the clear Film2 (+57.7% and +37.0% vs. +31.7% and +16.0%, in N50 and N75 respectively). Film1 boosted the total fruit production at all the N rates and with or without biostimulants, compared to Film2, with stronger effects under sub-optimal N (+29.4% in N50, +21.2% in N75, and +7.8% in N100, in plants untreated with biostimulant). Total yield decreased with decreasing N levels, while it always increased with the application of biostimulants, which counterbalanced the detrimental effects of N shortage. Quality traits were mainly affected by the cover film and the biostimulant treatment. The diffusive film increased the content of carotenoids, lycopene and total phenols compared to the clear one, and the biostimulants increased texture, soluble solids, phenols and ascorbic acid compared to the untreated control. It is worth noting that in plants fertilized at 75% of the reference N dose, the biostimulants determined higher yield than the N100 untreated control, under both the covers (+48% in Film1 and +20% in Film2). In conclusion, the diffusive film improved the fruit yield and quality of greenhouse tomatoes in the spring-summer period, presumably avoiding plant stress due to high-intensity direct light. Reduced N rates limited the plant productivity, however, the biostimulant application was effective in compensating for the detrimental effects of sub-optimal supply of N synthetic fertilizers.
As the productivity and quality of tomato fruits are responsive to Mg applications, without surpassing the threshold of toxicity, the assessment of potential levels of Mg accumulation in tissues, as ...well as the interactions with Ca and physicochemical properties, prompt this study. An agronomic workflow for Mg enrichment, consisting of six foliar applications of MgSO4 with four concentrations (0%, 0.25%, 1% and 4%), equivalent to 0, 43.9, 175.5 and 702 g ha−1, was applied on two tomato (Lycopersicum esculentum L.) genotypes (Heinz1534 and Heinz9205). During fruit development, leaf gas exchange was screened, with only minor physiological deviations being found. At harvest, Mg contents among tissues and the interactions with Ca were analyzed, and it was found that in both varieties a higher Mg/Ca ratio prevailed in the most external part of the fruit sprayed with 4% MgSO4. However, Mg distribution prevailed relatively near the epidermis in H1534, while in H9205 the higher contents of this nutrient occurred in the core of the fruit, which indicated a decrease of the relative proportion of Ca. The morphologic (height and diameter), physical (dry weight and density) and colorimetric parameters, and the total soluble solids of fruits, did not reveal significant changes in both tomato varieties. It was further concluded that foliar application until 4% MgSO4 does not have physiological impacts in the fruit’s quality of both varieties, but in spite of the different patterns of Mg accumulation in tissues, if the mean value in the whole fruit is considered, this nutrient prevails in H1534. This study thus suggests that variety H1534 can be used to attain tomato fruits with added value, providing an option of further processing to achieve food products with functional properties, ultimately proving a beneficial option to producers, the food processing industry and consumers. Moreover, the study reinforces the importance of variety choice when designing enrichment workflows.
Oxidative stress was investigated in Lycopersicum esculentum L. by applying various pesticides and boron compounds for two years, near Ortaca-Muğla. The field sections were treated separately by ...commercial pesticides and boron compounds i.e. tarimbor (TB), boric acid (BA), laser (LA), zoom (ZO) and admiral (AD). During first year, boric acid (BA-1) caused highest increase in total chlorophyll (TCh) content (158.41 μg g-1) while the second dose (BA-2) decreased it (103.11 μg g-1). During second year, higher doses of tarimbor (236.49 μg g-1) caused increase in total chlorophyll (TCh) while ZO treatment decreased it (142.55 μg g-1) (control: 149.55 μg g-1). TB-1 caused the highest increase in proline content (33.52 nmol g-1) while highest reduction was observed in boric acid (BA-2) (22.51 nmol g-1) as compared to control group (26.77 nmol g-1). During the first year, an increase of boric acid and tarimbor concentrations decreased malonaldehyde (MDA) while during the second year, both increases and decreases were observed in the MDA amount. Highest superoxide dismutase (SOD) amount was found in the first year ZO treated plants i.e. 70.35 unit SOD/mg protein while TB-1 treatment caused the highest decrease in the SOD amount i.e. 35.21 unit SOD/mg protein (control: 45.23 unit SOD/mg protein).
Oxidative stress was investigated in Lycopersicum esculentum L. by applying various pesticides and boron compounds for two years, near Ortaca-Muğla. The field sections were treated separately by commercial pesticides and boron compounds i.e. tarimbor (TB), boric acid (BA), laser (LA), zoom (ZO) and admiral (AD). During first year, boric acid (BA-1) caused highest increase in total chlorophyll (TCh) content (158.41 μg g-1) while the second dose (BA-2) decreased it (103.11 μg g-1). During second year, higher doses of tarimbor (236.49 μg g-1) caused increase in total chlorophyll (TCh) while ZO treatment decreased it (142.55 μg g-1) (control: 149.55 μg g-1). TB-1 caused the highest increase in proline content (33.52 nmol g-1) while highest reduction was observed in boric acid (BA-2) (22.51 nmol g-1) as compared to control group (26.77 nmol g-1). During the first year, an increase of boric acid and tarimbor concentrations decreased malonaldehyde (MDA) while during the second year, both increases and decreases were observed in the MDA amount. Highest superoxide dismutase (SOD) amount was found in the first year ZO treated plants i.e. 70.35 unit SOD/mg protein while TB-1 treatment caused the highest decrease in the SOD amount i.e. 35.21 unit SOD/mg protein (control: 45.23 unit SOD/mg protein).
We studied the comparable effect of gibberelic acid and tebuconazole on morphogenesis, mesostructure formation and redistribution of flows in sweet peppers and tomatoes. It has been found that the ...use of gibberelic acid and tebuconazole retardant during budding leads to increased plant productivity due to optimization of the structure and operation of the plants’ leaf apparatus. It was established that both gibberelic and antigibberelic tebuconazole drug stimulated the formation and functioning of the photosynthetic apparatus of peppers and tomatoes, but the mechanisms of this regulation were different. Increased photosynthetic activity of plants under the influence of gibberellin was determined primarily by the formation of more leaves and total leaf surface. When using tebuconazole retardant there was a significant restructuring of the organization of leaf mezostructure: the leaves were thickened by chlorenchyma proliferation, there was an increase in the volume of columnar parenchyma cells and linear dimensions of spongy parenchyma leaf cells. The surface density of leaves significantly increased, the chlorophyll content and nitrogen content (especially protein) also increased, compared with control variants and variants using gibberelin. Such a profound restructuring of the photosynthetic apparatus in plants under the actions of tebuconazole led to a significant increase in donor leaves function of peppers and tomatoes, which is an indicator of the growth of net productivity of photosynthesis – the highest among all the variants of the experiment. The results also show that increasing the chlorophyll phytocenotic index was more significant than the increase of leaf index: the tomatoes under the action of tebuconazole had a lower leaf index than in control options, but due to a higher chlorophyll index the crop productivity increased.Since during the fruiting period the costs of assimilates to the growth of vegetative organs are greatly reduced, optimization of photosynthetic apparatus in pepper and tomato plants led to the laying of more fruit per plant and increasing crop yield. The analysis of the mass ratio of the researched vegetative and fruit plants shows that the mass fraction of fruit (an acceptor sphere of plants during fruiting) under the action of both drugs increased. Thus in both variants of the experiment both the mass fraction and donor assimilates of leaves were higher. Apart from the main source of assimilates – the processes of photosynthesis, which intensified due to the formation of a larger area of leaf surface (variant with gibberelin) or optimization of mesostructure (variant with tebuconazole) it is probable that the formation and growth of the embryo occurred in part due to reutilization of carbohydrates from the vegetative plant organs in carpogenesis processes.
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