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Non-thermal plasma-activated water (PAW) is used in agriculture to decontaminate the seed/grains surface, with possible positive effects on physiological processes. In the present study, PAW was generated in ambient air at atmospheric pressure in eight variants with pH and different doses of reactive species (H2O2, NO3−). We explored the indirect effect of PAW on wheat grains while focusing on genetic material by cytogenetic monitoring. All PAW variants caused clastogenic and aneugenic events of the genetic material, with different intensities, in a dose-dependent manner of reactive species in plasma composition. PAW with the highest doses of H2O2 (13–22 mg/L) and NO3− (49–68 mg/L) at pH 3.8–4.1 decreased the mitotic index the most and induced the most frequent genetic abnormalities, out of which chromosomal bridges and micronuclei were dominant. In correlation with this damage at the nucleus level, the germination rate and root and shoot length of wheat sprouts decreased significantly only in the variants with the highest doses of reactive species. PAW with the lowest doses of H2O2 (1–5 mg/L) and NO3− (8–15 mg/L) at pH 5.5–5.1 induced a much lower cytogenotoxic potential, maintained a germination rate comparable to the control and even significantly stimulated root and shoot length growth. Thus, the effects of PAW depend highly on the dose of reactive species and on pH.

The prospect of replacing traditional chemical fertilization with organic and microorganism-based fertilization meets the current demand for more sustainable cropping systems and healthy food. In this respect, research was carried out to evaluate the effects of the factorial combination between four basil cultivars (‘Aromat de Buzau’, ‘Macedon’, ‘Cuisoare’ and ‘Serafim’) and three types of fertilization, namely chemical fertilization (with a solid chemical fertilizer), organic fertilization (with chicken manure formulate) and microorganisms’ fertilization (with microorganisms formulate), on basil yield, biochemical and physiological parameters and essential oil composition. The results showed that the biometric parameters (plant height, number of stems and leaves and leaf area) were significantly influenced by the cultivar; ‘Macedon’ obtained the highest values of plant height (64.7 cm) and number of stems (20.33) and leaves (618.3) and ‘Serafim’ the largest leaf area (4901.7 cm2 per plant), while the type of fertilization did not affect these parameters. Regarding the biomass, the influence of the cultivar was not significant on fresh biomass but was significant on dry biomass, with ‘Macedon’ showing the highest value (56.4 g·plant−1 dry biomass). The mentioned parameters were significantly influenced by the type of fertilization, with the highest values recorded with chemical fertilization. Both the cultivar and the fertilization type significantly influenced the physiological parameters (the total content of assimilatory pigments and photosynthesis). Five phenolic compounds were quantified from leaf extracts by HPLC-MS (caffeic acid, hyperoside, isoquercitrin, rutin and quercitrin). Hyperoside was identified only in ‘Macedon’, while the rest of the compounds were found in all the cultivars and varied depending on the cultivar and fertilization type. Regarding the composition of the essential oil, variation was found depending on the cultivar and fertilization type. In ‘Aromat de Buzau’, the main compounds were methyl chavicol and β-linalool; in ‘Macedon’, geranial and neral; and in ‘Cuisoare’ and ‘Serafim’, β-linalool. Moreover, the PCA showed that the ‘Serafim’ cultivar has exclusive properties compared to the other cultivars. Our results highlight that identifying the most effective interaction between genotype and fertilization type allows to optimize yield and quality targets for sweet basil.

Quinoa is an Andean grain known for its gluten-free grains, which are used as a functional food. The aim of this research was to study the possibility of introducing quinoa as a vegetable crop grown for young leaves as a source of polyphenols and phytosterols. To achieve this goal, a field experiment was performed with three quinoa cultivars (Titicaca, Puno, and Vikinga) grown in a split plot design. The experimental factors included three densities (160, 320, and 760 plants·m−2) and two harvest dates (52 and 62 days after sowing (DAS)). The content of phytosterols (ergosterol, stigmasterol, β-sitosterol and campesterol) and polyphenols (ferulic acid, isoquercitrin and rutozid) in quinoa leaves were determined by HPLC method. The phytosterol content varied within the limits: ergosterol 0–7.62 µg·100 g−1 dw, stigmasterol 79.9–175.3 µg·100 g−1 dw, β-sitosterol 425.7–623.1 µg·100 g−1 dw and campesterol 0–5.25 µg·100 g−1 dw. Ferulic acid varied greatly from 38.0 to 63.3 µg·g−1 dw, isoquercitrin ranged from 63 to 101.6 µg·g−1 dw and rutozid varied widely from 32.9 to 162.8 µg·g−1 dw. The total phytosterols and the total phenolic compounds decreased with decreasing plant number density and DAS. This research demonstrated that young quinoa leaves are a good source of phytosterols and phenolics for human consumption.

Fertigation is considered an efficient alternative to the enhanced use of chemical fertilizers. Since most of the fertigation systems rely on a theoretical electrical conductivity value of the nutrient solution, we tried to evaluate if this is the real need of the plants as well as if all the nutrients are needed at once. Therefore, we analyzed the electrical signals of the nutrients applied individually or in different mixes, correlating the electrical signals with the leaf gas exchange processes, studying the relation between the electrical signals and different plant phenological stages and the influence of the treatments on the lycopene content, nutritional composition, and antinutritional factors as well as the mineral bioavailability of tomato fruits cv. Brillante F1. The study was carried out in a greenhouse under controlled conditions. Ten different treatments consisting of MaEs (major elements) (V1—MgSO4, V2—KNO3, V3—K2SO4, V4—Ca(NO3)2, V5—KH2PO4, V6—KCl, V7—MgSO4 + KNO3 + KH2PO4, V8—K2SO4 + Ca(NO3)2 + KCl, V9—the mix of V1 to V6, commonly used in agricultural practices, V10—one nutrient each day) were applied daily when plants were 42 days old. The results showed that the values of the electrical signals varied depending on the treatment and the plant phenological stage. Five different trends of the electrical signals were identified. In addition, the shape of the signals varied during the day in accordance with the photosynthesis and the amount of CO2 registered. The results of the treatments’ influence on the nutritional composition and lycopene content of tomato fruits suggested that plants do not need all the nutrients at once; the highest values are registered for K2SO4 fertilization. However, this fertilizer also had the highest registered tannin, saponin, and trypsin inhibitors content, constituting a disadvantage considering the high nutritional values and lycopene content. Regarding the bioavailability of zinc, calcium, and iron for the human diet, regardless of the treatment applied, phytic acid did not affect the availability of zinc and calcium, but it had a negative impact on iron availability; also, the amount of oxalate could impair the bioavailability of calcium. The study suggests that tomato plants do not need all nutrients at once for quality fruits. However, further studies are needed in order to develop a fertigation scheme based on a smart nutrient use that provides an improved nutritional composition and mineral bioavailability. In addition, it is necessary to evaluate the influence of treatments on yield.

Salinity and alkalinity are two of the main causes for productivity losses in agriculture. Quinoa represents a better alternative for global food products such as rice and wheat flour due to its high nutritional value and abiotic stress tolerance. Three cultivars of quinoa seeds (Titicaca, Puno and Vikinga) originating from Denmark were used in the experiments. The seeds were germinated under the action of three different salts (NaCl, Na2SO4, Na2CO3) at 0−300 mM for five days and the germination rate was calculated. Biometric measurements (radicle and hypocotyls lengths) andbiochemical determinations (proline) were performed in order to quantify the tolerance and the effects of salt and alkali stresses on the three quinoa cultivars. The germination rates showed that all cultivars were affected by the presence of salts, especially at 300 mM. The most sensitive cultivar to salts was Titicaca cultivar which evinced the lowest germination rate, regardless of the salt and the concentration used. On the other hand, Puno and Vikinga cultivars showed the best tolerance to the saline and alkaline stresses. Among the salts used, Na2CO3 had the most detrimental effects on the germination of quinoa seeds inhibiting the germination by ~50% starting with 50 mM. More affected was the growth of hypocotyls in the presence of this salt, being completely inhibited for the seeds of the Puno and Titicaca cultivars. Vikinga cultivar was the only one able to grow hypocotyls at 50 and 100 mM Na2CO3. Also, this cultivar had a high adaptability to NaCl stress when significant differences were observed for the germination rates at 200 and 300 mM as compared to 0 mM NaCl, due to the proline production whose content was significantly greater than that of the untreated seeds. In conclusion, the tolerance of the three quinoa cultivars to saline and alkali stress varied with the salt type, salt concentration and tested cultivar, with the Vikinga and Puno cultivars showing the best potential for growing under saline conditions.

The plastic mulch has raised a disposal issue, which has been diverting the research focus on biodegradable film as an alternative. Research was carried out in southern Italy in 2016–2017 and 2017–2018 in order to assess the effects of three crop cycles (autumn-winter, winter, spring) in factorial combination with three soil mulching types (a MaterBi biodegradable black film; a brown photoselective low density polyethylene (LDPE) film; a black-standard LDPE film) and a non-mulched control, on leaves yield, quality and antioxidants of greenhouse grown Diplotaxis tenuifolia (L.) D.C. The spring cycle was the shortest and best enhanced plant growth and yield. The non-mulched control caused an 11% yield reduction compared to the mulching treatments average (12.4 t ha−1). The soil temperature was highest under photoselective and standard LDPE films. The Soil Plant Analysis Development (SPAD) index was 17.4% higher in the leaves grown in mulched soil. Winter season and biodegradable mulch led to higher leaf dry residue and organic acids. Leaf nitrate content was highest in winter and under mulching. The spring cycle, the biodegradable and photoselective LDPE film resulted in the highest antioxidant compound content and activity. The biodegradable polymer improved leaf quality, showing suitable features for sustainable production.