Search Results (106)

In this study, gravlax, a niche Scandinavian delicacy, was comprehensively investigated by producing it with combinations of two different fish species (tub gurnard (Chelidonichthys lucerna Linnaeus, 1758) and garfish (Belone belone Linnaeus, 1761)) and five herbs (dill (Anethum graveolens Linnaeus, 1753), sage (Salvia officinalis Linnaeus, 1753), mint (Mentha piperita Linnaeus, 1753), sweet (Ocimum basilicum Linnaeus, 1754), and purple basil (Ocimum basilicum var. purpurascens Bentham, 1830)). The nutritional composition, amino acids, color parameters, mineral substances, and heavy metal content, as well as physical characteristics, texture profile analysis, and extensive sensory analyses, were conducted, and the results were thoroughly evaluated using multivariate statistical methods. The influence of using different herbs on nutritional composition was found to be significant in gravlax made from both fish species (p < 0.05). Sensory analyses revealed that panelists identified mint as enhancing aroma and umami sensations, while dill improved overall acceptance. Gravlax with sage exhibited softer textures, but lower general acceptance due to perceived high saltiness. Color analyses revealed that purple basil transferred distinct pigments, causing darkening, whereas sweet basil had a brightening effect. Amino acid analyses revealed higher umami and sweet-tasting amino acids in herb-free gravlax, whereas proteolytic activity appeared to slow down in herb-containing gravlax samples. Full article

It is necessary to explore possibilities to increase agricultural production in environmentally friendly ways while maintaining the quality standards of plant raw materials. The effect of amino acids on sweet basil (Ocimum basilicum L.) development may stimulate biomass accumulation and enhance the biosynthesis of secondary metabolites. Investigated varieties “Rosie”, “Red Opal”, “Bordeaux”, “Dark Opal”, “Red Rubin”, “Genovese”, “Cinamon”, “Italiano Classico”, “Marseillais”, and “Thai” were cultivated in a controlled-environment growth chamber and the impact of isoleucine, methionine, glutamine, tryptophan, phenylalanine was studied on biomass accumulation, chlorophyll and phenolic content, and antioxidant activity. Five to six true leaves plants were treated once with an aqueous solution containing 100 mg L⁻¹ of the mentioned amino acids or received no treatment. Our results show that methionine or tryptophan improved the most fresh and dry weight of shoot system of sweet basil plants. Methionine increased chlorophyl a content in 6 of 10 sweet basil varieties, while glutamine had the greatest results in chlorophyl b content. Phenylalanine increased total phenolic content in most treated plants, as well as antioxidant activity. Amino acids may be applied as useful biostimulants in modern agriculture, as they play an important role in ensuring sustainable crop productivity, fostering beneficial plant properties. Full article

Soil moisture sensor-based drip irrigation enables efficient irrigation practices by delivering the required water to plants. However, efficiency must be accompanied by uniform water management and crop growth. This study examined the effect of different irrigation amounts (IAs) per application (5.5, 55, 110, and 165 mL) on the uniformity of substrate volumetric water content (VWC) within an irrigation plot, and the corresponding effect on sweet basil growth uniformity. Sixty-four frequency domain reflectometry sensors monitored the VWC of each 440 mL pot, and drip irrigation was automatically applied at 0.3 m³·m⁻³. The 5.5 mL IA showed the highest water use efficiency; however, it also resulted in considerable non-uniform VWC (coefficient of variation, CV = 0.404). In contrast, the 110 and 165 mL IAs provided better VWC uniformity (CV = 0.073 and 0.075, respectively), suggesting that less frequent, but larger IAs improved VWC uniformity. Despite the differences in VWC uniformity among treatments, the growth and physiological responses were quite similar across the treatments. It was found that supplying 110 mL irrigation water via the soil moisture sensor-based drip irrigation system to sweet basil plants in 440 mL pots is optimal for achieving both water use efficiency and VWC uniformity. Full article

The integration of precision agriculture technologies, such as remote sensing through drones and satellites, has significantly enhanced real-time crop monitoring. This study is among the first to combine multispectral data from both a drone equipped with Altum-PT camera and PlanetScope satellite imagery to predict fresh biomass in sweet basil grown in an open field, demonstrating the added value of integrating different spatial scales. A dataset of 40 sampling points was built by combining remote sensing data with field measurements, and seven vegetation indices were calculated for each point. Feature selection was performed using three different methods (F-score, Recursive Feature Elimination, and model-based selection), and the most informative features were then processed through Principal Component Analysis. Eight regression models were trained and evaluated using leave-one-out cross-validation. The best-performing models were Random Forest (R² = 0.96 in training, R² = 0.65 in testing) and k-Nearest Neighbours (R² = 0.74 in training, R² = 0.94 in testing), with kNN demonstrating superior generalization capability on unseen data. These findings highlight the potential of combining drone and satellite imagery for modelling basil agronomic traits, offering valuable insights for optimizing crop management strategies. Full article

This study investigates the effectiveness of organic compost as a sustainable alternative to chemical fertilizers for improving soil health and enhancing crop productivity under greenhouse conditions. The experiment focused on sweet basil (Ocimum basilicum L.), an aromatic herb highly sensitive to soil fertility and structure, cultivated in sandy loam soil—a prevalent substrate in arid and semi-arid regions, often limited by poor water and nutrient retention. Using a randomized complete block design with six compost application rates, this study evaluated the physicochemical, biochemical, and agronomic responses of both soil and plants. The results demonstrated significant improvements across all parameters (p < 0.05), with the 30 t/ha compost treatment yielding the most notable enhancements in soil structure, nutrient content, and plant performance while maintaining acceptable levels of heavy metals. Soil organic matter (SOM) increased to 13.71%, while shoot length (SL), essential oil content (EOC), and the 100-seed weight improved to 42 cm, 0.83%, and 0.32 g, respectively, compared to the control. These finding underscore the benefits of high compost application rates in boosting greenhouse horticultural productivity while promoting sustainable agriculture. Moreover, this study supports the reduction in chemical fertilizer dependency and encourages the adoption of circular economy principles (CEPs) through organic waste recycling. Full article

The effect of lighting basil with LED DR/B LB (Light Emitting Diode deep red/blue low blue) lamps throughout the cultivation cycle or for only 7 days before harvest, after the period of using HPS (High Pressure Sodium) lamps, was studied in comparison with the use of HPS lamps only, at the same light intensity. Plants of two Genovese type basil cultivars, recommended for pot and hydroponic cultivation, were used for the experiment. Plant growth observations were made and herb and leaf yields, dry matter, nitrates, potassium, phosphorus, calcium, total sugars, total soluble solids, ascorbic acid, chlorophylls, and carotenoids were determined. Plants of both tested basil cultivars grown under LED lighting were characterized by a higher content of ascorbic acid, carotenoids, and sugars and a lower content of nitrates than those grown under HPS lights. In plants grown under LED lighting only, nitrate content was on average 31% lower than under HPS lamps. The use of LEDs for the last 7 days of cultivation resulted in a significant reduction in nitrate content in only one of the studied cultivars. Further research on the effect of lighting type on sweet basil yield and quality, depending on other factors, both genetic and environmental, is recommended. Full article

Honeybees are of economic importance not only for honey production, but also for crop pollination, which amounts to USD 20 billion per year in the United States. However, the number of honeybee colonies has declined more than 40% during the last few decades. Although this decline is attributed to a combination of factors (parasites, diseases, pesticides, and nutrition), unlike other factors, the effect of nutrition on honeybee health is not well documented. In this study, we assessed the differential expression of seven genes linked to honeybee health under three different diets. These included immune function genes [Cactus, immune deficiency (IMD), Spaetzle)], genes involved in nutrition, cellular defense, longevity, and behavior (Vitellogenin, Malvolio), a gene involved in energy metabolism (Maltase), and a gene associated with locomotory behavior (Single-minded). The diets included (a) commercial pollen patties and sugar syrup, (b) monofloral (anise hyssop), and (c) polyfloral (marigold, anise hyssop, sweet alyssum, and basil). Over the 2.7-month experimental periods, adult bees in controls fed pollen patties and sugar syrup showed upregulated Cactus (involved in Toll pathway) and IMD (signaling pathway controls antibacterial defense) expression, while their counterparts fed monofloral and polyfloral diets downregulated the expression of these genes. Unlike Cactus and IMD, the gene expression profile of Spaetzle (involved in Toll pathway) did not differ across treatments during the experimental period except that it was significantly downregulated on day 63 and day 84 in bees fed polyfloral diets. The Vitellogenin gene indicated that monofloral and polyfloral diets significantly upregulated this gene and enhanced lifespan, foraging behavior, and immunity in adult bees fed with monofloral diets. The expression of Malvolio (involved in sucrose responsiveness and foraging behavior) was upregulated when food reserves (pollen and nectar) were limited in adult bees fed polyfloral diets. Adult bees fed with monofloral diets significantly upregulated the expression of Maltase (involved in energy metabolisms) compared to their counterparts in control diets to the end of the experimental period. Single-Minded Homolog 2 (involved in locomotory behavior) was also upregulated in adult bees fed pollen patties and sugar syrup compared to their counterparts fed monofloral and polyfloral diets. Thus, the food source significantly affected honeybee health and triggered an up- and downregulation of these genes, which correlated with the health and activities of the honeybee colonies. Overall, we found that the companion crops (monofloral and polyfloral) provided higher nutritional benefits to enhance honeybee health than the pollen patty and sugar syrup used currently by beekeepers. Furthermore, while it has been reported that bees require pollen from diverse sources to maintain a healthy physiology and hive, our data on nuclear colonies indicated that a single-species diet (such as anise hyssop) is nutritionally adequate and better or comparable to polyfloral diets. To the best of our knowledge, this is the first report indicating better nutritional benefits from monofloral diets (anise hyssop) over polyfloral diets for honeybee colonies (nucs) in semi-large-scale experimental runs. Thus, we recommend that the landscape of any apiary include highly nutritious food sources, such as anise hyssop, throughout the season to enhance honeybee health. Full article

Ocimum basilicum is an herbaceous plant, rich in essential oils. This research represents a groundbreaking exploration of the cultivation of Ocimum basilicum in Greece, a Mediterranean nation. It emphasizes the impact of biostimulants on various basil varieties, assessing both quantitative aspects and qualitative features. This study was conducted through a field trial at the University of Thessaly’s experimental farm located in the Velestino region. This study examined different testing varieties (V1: Lemon, V2: Siam Queen, V3: Salat, V4: Bascuro, and V5: Genovese), under different biostimulant applications (B1: control, B2: seaweed extracts, amino acids, vitamins, trace elements, polyphenols, antioxidants and mannitol; B3: plant amino acids, glutamic and aspartic acid, vitamins and other nutrients, B4: B1 and B2 combination in a 1:1 ratio). The findings highlight the significant differences in both fresh and dry yields across various basil cultivars, with Lemon basil demonstrating the most substantial yields. Specifically, the Lemon variety attained the highest dry yield, surpassing the lowest-performing cultivar by more than two times. Additionally, this research evaluated the production of essential oil per hectare, emphasizing the relationship between essential oil content and the crop’s dry yield. The results revealed considerable variability among the examined varieties, with the Lemon variety yielding nearly 65 kg ha⁻¹, the highest among them. Biostimulant treatments (B2) led to the greatest total yields of essential oils, while the control treatments yielded the least. The chemical composition of essential oils derived from O. basilicum shows significant variability, often associated with the plants’ nutritional conditions. The application of biostimulants has led to considerable alterations in the volatile profile of sweet basil, supporting this study’s conclusions. Full article

The production of Ocimum basilicum (basil) crop depends upon the availability of all nutrients in the soil solution. There is a lack of information about its performance, at tropical conditions, using new fertilizer formulations, such as organo-mineral fertilizers, mainly under protected cultivation. These types of fertilizers combine benefits of the main fertilizers used in agriculture (organic and chemical). Therefore, organo-mineral fertilizers enhance soil health, provide a balanced nutrient supply, improve crop yields and quality. and promote environmental sustainability, making them a cost-effective and eco-friendly solution for sustainable crop production. This work aimed to evaluate the biomass and essential oil of basil varieties, with organo-mineral fertilization in different agricultural systems. Each experiment was conducted in a randomized block design, with three replications in a 2 × 4 factorial scheme, being two varieties of basil (“Sweet Dani” and “Cinnamon”) and four fertilizers: organo-mineral source, mineral source, organic source and the natural fertility of the soil. The evaluated characteristics were plant height, fresh biomass of plants, content, yield and the chemical composition of the essential oil. The organo-mineral sources of fertilizer provide better values for fresh biomass (average of 1175.90 and 1032.83 g per plant via greenhouse cultivation and field cultivation, respectively), essential oil yield (14.57 and 11.89 g per plant via greenhouse cultivation and field cultivation, respectively) and the dominant compounds for both cultivars of O. basilicum. Protected cultivation is the better environmental condition for obtaining the highest performance of O. basilicum cultivars about biomass and essential oil. The content of essential oil is not affected by the agricultural systems (greenhouse and field). The major compounds of essential oil under Brazilian crop conditions are Linalol and (E)-mehyl cinnamate in “Cinnamon” and neral and geranial (citral) in “Sweet Dani”. Full article

Sweet basil (Ocimum basilicum L.) is highly susceptible to chilling injury (CI), resulting in the development of CI symptoms during cold storage that reduce postharvest quality and shelf life. This study evaluated whether silicon (Si) and abscisic acid (ABA) applications can mitigate these symptoms. In Trial 1, basil plants had a Si solution (189 mg/L Si from potassium silicate) or deionised water (control) applied during cultivation via rootzone irrigation or foliar spray. Some plants were also foliar sprayed with ABA (1000 mg/L) before harvest. In Trial 2, wollastonite was added to the growing media (0, 1, 2, 3, 4, 5 mL/L) as the Si source. Applying the Si solution using either method reduced leaf necrosis, fresh weight loss, and electrolyte leakage, extending shelf life to at least 14 days. There were also no negative impacts on plant performance during cultivation (chlorophyll content, shoot height, and canopy width). The ABA solution, alone or in combination with Si solution, reduced symptoms but less effectively, extending shelf life up to 8 days. Wollastonite had no positive effects. These findings suggest that Si solution applications are a promising strategy to alleviate CI during postharvest cold storage of basil at 3.5 °C. Full article

Sweet basil (Ocimum basilicum) is valued for its culinary and medicinal properties. It thrives in full sunlight and long daylight hours under natural conditions. This study examined the effects of extended photoperiod on sweet basil grown in a hot and humid tropical greenhouse. Some plants received only natural sunlight (SL), while others had SL supplemented with LED light for 6 h (6 h) before sunrise and/or after sunset. Plants grown under only natural SL (L1) had a smaller leaf number, smaller leaf area per plant, lower shoot, and root productivity than those grown under other light conditions. The shoot fresh weight of basil grown under supplemented LED light for 3 h before sunrise and 3 h after sunset (L2), 6 h after sunset (L3), and 6 h before sunrise (L4) was 2.68, 2.33, and 1.94 times higher than L1 conditions, respectively. The maximum quantum efficiency of PSII, electron transport rate, effective quantum yield of PSII, and Chl a/b ratio were also higher in L2, L3, and L4. The total leaf soluble protein, ascorbic acid, total phenolic compounds, and dietary minerals followed the same trend. Among all treatments, L2 consistently showed significantly higher values, making it the optimal lighting strategy for extended photoperiod. Full article

Controlled-environment crop production often weakens plants’ defense mechanisms, reducing the accumulation of protective phytochemicals essential to human health. Our previous studies demonstrated that short-term supplementation of low-dose ultraviolet (UV) light to the red–green–blue (RGB) spectrum effectively boosts secondary metabolite (SM) synthesis and antioxidant capacity in lettuce. This study explored whether similar effects occur in basil cultivars by supplementing the RGB spectrum with ultraviolet B (UV-B, 311 nm) or ultraviolet C (UV-C, 254 nm) light shortly before harvest. Molecular analyses focused on UV-induced polyphenol synthesis, particularly chalcone synthase (CHS) level, and UV light perception via the UVR8 receptor. The impact of high-energy UV radiation on the photosynthetic apparatus (PA) was also monitored. The results showed that UV-B supplementation did not harm the PA, while UV-C significantly impaired photosynthesis and restricted plant growth and biomass accumulation. In green-leaf (Sweet Large, SL) basil, UV-B enhanced total antioxidant capacity (TAC), increasing polyphenolic secondary metabolites and ascorbic acid (AsA) levels. UV-C also stimulated phenolic compound accumulation in SL basil but had no positive effects in the purple-leaf (Dark Opal, DO) cultivar. Interestingly, while the UV-B treatment promoted UVR8 monomerization in both cultivars, the enhanced CHS level and concomitant SM synthesis were noted only for SL basil. In addition, UV-C also induced CHS activity and SM synthesis in SL basil but clearly in a UVR8-independeted manner. These findings underscore the potential of UV light supplementation for enhancing plant functional properties, highlighting species- and cultivar-specific effects without compromising photosynthetic performance. Full article

Climate change poses a significant threat to food security, with projections indicating a decline in crop yield due to reduced crop growth in the face of rising temperatures. This study evaluated the effects of L-Isoleucine, L-Methionine, L-Glutamine, L-Tryptophan, and L-Phenylalanine on the morphophysiological parameters, total phenolic content, and antioxidant activity of Sweet Basil (Ocimum basilicum L.) under high-temperature stress. Ten cultivar varieties of the sweet basil, “Rosie”, “Red Opal”, “Bordeaux”, “Dark Opal”, “Red Rubin”, “Genovese”, “Cinamon”, “Italiano Classico”, “Marseillais”, and “Thai”, were grown in a controlled-environment growth chamber. The seedlings with 5–6 true leaves were divided into seven groups: the first group of seedlings had no treatment and was grown under 25/22 °C (day/night) temperature, the second group of seedlings had no treatment and was grown under 35/30 °C (day/night) temperature, and the remaining five groups were sprayed with 100 mg L⁻¹ of L-Isoleucine, L-Methionine, L-Glutamine, L-Tryptophan, or L-Phenylalanine. As our results show, L-Tryptophan increased fresh and dry biomass in green sweet basil, while L-Methionine had the greatest effect on biomass in purple varieties. L-Phenylalanine increased chlorophyll a and b in heat-stressed “Bordeaux” (purple variety) and “Marseillais” (green variety). L-Isoleucine and L-Glutamine increased total phenolic compounds (TPCs) in purple cultivars (“Rosie”, “Red Opal”, “Dark Opal”, and “Red Rubin”), while L-Tryptophan (“Cinamon” and “Italiano Classico”) and L-Phenylalanine increased TPCs in “Cinamon”, “Marseillais”, and “Thai” green cultivars. Antioxidant activity (ABTS) was highest in “Dark Opal” and “Bordeaux” treated with L-Tryptophan or L-Phenylalanine under heat stress, while “Thai” benefited most from L-Isoleucine. The exogenous application of amino acids could serve as a viable solution to alleviate the negative effects of temperature stress on sweet basil and serve as an environmentally friendly agricultural strategy. Full article

Basil, renowned for its aromatic properties, exhibits commendable drought tolerance and holds significant value as an edible and medicinal plant. Recognizing the scarcity of studies addressing basil’s response to drought stress, we performed physiological experiments and omics analyses of sweet basil across four distinct levels of drought stress. During drought stress, basil showed increased activity of antioxidant enzymes and accumulated more osmoregulatory compounds. Our metabolic analysis meticulously identified a total of 830 metabolites, among which, 215 were differentially accumulated. The differentially accumulated metabolites under drought stress were predominantly esters and terpenes; however, none were identified as the primary volatile compounds of basil. Transcriptome analyses highlighted the pivotal roles of phenylpropanoid and flavonoid biosynthesis and lipid metabolism in fortifying the resistance of sweet basil against drought stress. α-linolenic acid, lignin, flavonoid, and flavonol contents significantly increased under stress; the essential genes involved in the production of these compounds were confirmed through quantitative real-time PCR (qRT-PCR), and their variations aligned with the outcomes from sequencing. This holistic approach not only enriches our understanding of the molecular intricacies underpinning basil’s drought resistance but also furnishes valuable insights for the molecular breeding of basil varieties endowed with enhanced drought tolerance. Full article

The cultivation of aromatic plants that are valuable for nutritional and medical aims under artificial conditions with narrow-band LED lighting is becoming widespread. A comparison of the effects of conventional basil field and greenhouse conditions and a city farm (CF) with LED lighting on essential oil and its components was studied in Ocimum × citriodorum Vis. “Kapriz” (OcK), O. basilicum L. “Queen Sheba” (ObQS) and O. minimum L. “Vasilisk” (OmV). Essential oil (EO) was extracted by hydrodistillation from dry leaves of the basil varieties. EO composition was studied by gas chromatography, while the number of glandular trichomes was studied by scanning electron microscopy. We found that in leaves of CF plants, ObQS and OmV increased EO yield (22.9 and 22.7 g/kg DW, respectively) compared to field conditions (10.9 and 13.7 g/kg DW, respectively). The number of glands with four-celled heads also increased. In OcK plants, the amount of EO was almost unchanged, but the number of capitate glandular trichomes was strongly increased. Biochemical analysis showed that in CF plants compared to field ones, eugenol accumulated 40% more in ObQS and three times more in OmV. In addition, 10.9% estragol was detected in the leaves of OcK plants, which was absent in field plants. Thus, LED lighting conditions increased the biosynthesis of phenylpropanoid volatile components in Ocimum. Full article