In recent years, there has been growing interest in Tulipa tarda, a species belonging to the botanical tulip group, in the bulb plant market. This species is valuable as a bedding plant, mainly due to its multi-flowered stems and star-shaped, yellow flowers blooming in April, but also due to its ability to grow in one place for many years.

The low efficiency of traditional tulip propagation has led to the search for more effective in vitro propagation methods. The presented research focused on the formation of adventitious bulbs using methyl jasmonate (Me-JA) as a factor influencing micropropagation among ornamental geophytes.

The experiment used scales from adventitious bulbs obtained from an in vitro collection of T. tarda at the University of Agriculture, Kraków. The bulb scales (approx. 10 mm length, 4 mm width) were cultured in Petri dishes on MS solid medium containing 6% sucrose, 0-400 mg l^-1 Me-JA, and 0-0.5 mM 6-benzyl-aminopurine (BAP). After four weeks, Me-JA was removed from the medium. The cultures were maintained in the dark at 20°C.

After 12 weeks of culture, the presence of Me-JA alone in the medium reduced bulb formation. However, the combined application of 100 mg l^-1 Me-JA and 0.5 mM BAP enhanced the propagation efficiency (with 86% of explants forming bulbs) in comparison to the control (BAP treatment, with 70% of explants forming bulbs). Higher concentrations of Me-JA significantly reduced adventitious bulb regeneration, with only 38% of explants forming bulbs. An average of 1.2 adventitious bulbs per explant was obtained, which was not significantly higher than the control (1.1 bulbs per explant). All adventitious bulbs formed roots at a similar level (approx. 3 roots/bulb). The bulbs also began to develop leaves. The treatment with 100 mg l^-1 Me-JA and 0.5 µM BAP led to twice as many bulbs developing leaves (22%) compared with the control (10%).

In conclusion, the combined application of 100 mg l^-1 Me-JA and 0.5 mM BAP positively influenced adventitious bulbs regeneration and leaf development.

Future research should investigate the long-term viability of these bulbs and assess their performance under greenhouse or field conditions.

Leafy vegetables often need a high quantity of water to grow and among the most critical factors and stressors are high soil and water salinity levels and the concomitant reduction in optimum arable areas. Salinity increases by the intrusion of salts in the underground and surface water due to overfertilization and reduces the amount of available freshwater for irrigation (Kumar, 2022). In the EU, especially in the southern European Member States, most of all arable land will be affected by salinization and yields of non-irrigated crops are projected to decrease by up to 50 % by 2050 (Christopoulos and Ouzounidou, 2021). The objective of this study was to evaluate irrigation with high-salinity water (ECi= 10 dS/m) with the application of two innovative technologies for growing leafy vegetables species in four different tanks. One technology is the use of a nanobubble (NB) generator (Hephaestus Lab: https://chem.duth.gr/) and the other is an electronic water treatment system, using low-frequency radiation waves (MAXGROW: https://maxgrow.tech/). The study was conducted in the Greenhouse Laboratory of the Perrotis College/American Farm School, Thessaloniki, Greece, under a floating-disk hydroponic system, in which three leafy vegetables species (endive and two lettuce varieties, Lollo Rossa and Butterhead) were grown in four different sections/tanks, each one filled with irrigation water of different salinity: a. Control (E.C.i ~1 dS/m); b. saline water (E.C.i = 10 dS/m) enriched with NB; c. saline water (E.C.i = 10 dS/m) + MAXGROW; and d. saline water (E.C.i = 10 dS/m) + MAXGROW + NB. Various vegetable agronomic parameters (total fresh weight, height, root weight, SPAD units, etc.), plant tissue analysis (macro- and micronutrients), water parameters (dissolved oxygen, pH, EC, nutrients, temperature, size and concentration of NB, etc.), and the environmental conditions [temperature (^oC), humidity (%), PAR, and CO₂] inside the greenhouse were recorded. Additionally, quality parameters (Chlorophyll, flavanols, anthocyanins, etc.) were measured. This study will continue with evaluations in different vegetable species, growing seasons, and hydroponic systems to further assess the potential of the innovative system used in high salinity levels. The results so far showed that both water treatment devices increased yield. Finally, both innovative technologies could provide efficient energy use, low operation cost, and sustainability and mitigate high-salinity irrigation problems in crop production systems.

Crocus sativus L., known for the precious spice of saffron, is a geophyte propagated through underground corms. Corm size influences both spice yield and the production of new corms, as corms below 10 g do not produce flowers in the same year. Saffron is mainly grown in open fields, but there is an increasing interest in growing it under controlled conditions. Precision farming can increase crop productivity, sustainability, and profitability by optimising input use through precise nutrient dosing. Therefore, the aim of this study was to evaluate the possibility of reducing nitrogen and phosphorus levels in soilless saffron cultivation without affecting production and quality. The experiment was carried out in an unheated greenhouse. Corms ≥19 g were planted at the end of the summer in 4 L pots, with one corm per pot, using sterile expanded perlite as the growing medium. Fertigation was applied every two weeks until leaf senescence in spring, using two different solutions: a modified Long-Ashton solution containing 600 μM phosphorus (P) and 2 mM nitrogen (N), and another Long-Ashton solution with half the concentrations of P (300 μM) and N (1 mM). Surveys were conducted on spice yield and quality during the flowering phase, as well as on morphological and physiological parameters along with corm yield during the vegetative phase. The results showed that the reduced concentration of the two macronutrients did not affect the analysed parameters. In both treatments, the spice yield was ~29 mg per corm and its quality was in the category I (ISO 3632). Leaf length (~38 cm), number (~42), and photosynthesis (E= 3.2 mmol m-2 s-1, A= 6.7 µmol m-2 s-1, gs= 174.2 mmol m-2 s-1, Ci= 480.5 ppm) were also not affected. Lastly, corm production was ~5.5 per plant, with an average weight of ~3.2 g. These results are consistent with the fact that corm growth mainly depends on photosynthesis during the winter vegetative phase. Thus, fertiliser reduction could be a viable strategy for sustainable saffron production in soilless systems, potentially reducing environmental impacts and costs without compromising crop quality or yield.

Influence of drought-priming on the improvement of cold-hardiness in grapefruit (Citrus paradisi) through the enhancement of physiological and biochemical attributes

Shahid Iqbal (shahidiqbal@ufl.edu) * USA

Carlos Eduardo Aucique-Perez (c.auciqueperez@ufl.edu) * USA

Muhammad Adnan Shahid (mshahid@ufl.edu) * USA

Priming is a phenomenon through which plants are initially exposed to one type of stress to prepare them to better handle another. There is a lack of scientific knowledge regarding the effect of drought-priming on the freeze tolerance mechanism in cold-sensitive grapefruit (Citrus paradisi). To investigate whether pre-freezing drought stress can serve as a primer in cold-hardiness, we subjected plants to drought-priming (50%, 75%, and 100% field capacity) and post-priming freezing stress (-6 °C). Drought-priming memory was found to enhance the ability of plants to withstand freezing temperatures by regulating their antioxidant system, osmolyte production, and carbohydrate metabolism. Drought-priming triggered the activities of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), glutathione peroxidase (GPX), and ascorbate peroxidase (APX), in the range of 1.21, 0.11, 0.10, 1.42, 0.41, and 1.16 U mg^-1 protein, respectively, to reduce oxidative damage caused by an excessive formation of reactive oxygen species (ROS) like superoxide (O₂^•-) and hydrogen peroxide (H₂O₂), with a minimum concentration of 0.10 and 0.44 nmol g^-1 protein in primed plants. Drought-priming also accelerated the accumulation of osmolytes, including proline (0.91 mg g^-1 FW) and glycine betaine (0.98 mg g^-1 FW), and soluble sugars such as glucose (12.58 mg g-1 DW), fructose (6.60 mg g-1 DW), and sucrose (19.85 mg g-1 DW), which help stabilize cellular structures and maintain osmotic balance under stressed conditions. Drought-primed plants also showed modulated carbohydrate metabolism, sugar biosynthesis, and reduced starch reserves. These adaptive changes helped plants better cope with subsequent freezing stress, improving their resilience by sustaining energy production, maintaining cellular integrity, and ensuring metabolic activity. This corresponding response highlights the valuable impact of drought-priming in improving cold-hardiness in young grapefruit plants through a comprehensive physiological and biochemical stress-alleviating mechanism and highlights the practical potential of drought-priming as a cost-effective and non-invasive strategy to improve cold-hardiness in citrus and related species. By integrating drought-priming into management practices, growers can enhance the resilience of young grapefruit plants to freezing conditions, contributing to sustainable citrus production in regions prone to cold stress or unexpected freeze events in winter or late summer.

Numerous marketing studies have shown that consumer groups exhibit different preferences and purchasing behaviours, influenced by various factors. Ensuring business stability and growth requires a strong market orientation and effective strategies, emphasising the importance of monitoring consumer preferences and behaviour. This is particularly critical for perishable goods, such as ornamental plants. While research in this sector has focused primarily on cut flowers, potted plants, and nursery trees, there is a significant gap in studies addressing ornamental perennials, despite their growing popularity among individual consumers and businesses specialising in garden and landscape design.

This study assessed consumer preferences and behaviour regarding the purchase of ornamental perennials in different stationary retail outlets across the Małopolska region of Poland. A survey conducted from July to September 2022 covered twenty locations in three types of areas based on population density: Kraków (over 100,000 inhabitants), Gorlice (up to 30,000 inhabitants), and four rural villages, with research conducted at four types of retail outlets in each: garden centres, nurseries, florists, and DIY/home improvement stores. A total of 202 verified surveys, featuring 15 closed-ended questions and a demographic section, were included in the analysis.

Consumers, regardless of age or gender, most frequently purchase perennials from specialised outlets such as nurseries and garden centres, valuing these places for their perceived high-quality products, wide selection, and professional advice. In large cities, large-scale retail stores are also popular, while florists dominate in smaller towns due to greater availability. Price is not a major determinant for most consumers; however, younger and older respondents tend to prefer smaller, cheaper plants, likely due to financial constraints. Online purchases of perennials remain rare, primarily because consumers value the ability to assess plant quality and seek professional advice.

Gender-based preferences are significant. Men prioritise plants with bold, classic inflorescences, such as peony- or lily-like flowers in white or red, as well as decorative foliage. Women, in contrast, favour intensely flowering, fragrant plants with delicate structures in pink, purple, or white. Women are also more inclined to select plants that promote biodiversity and use recycled packaging, a trend also observed among the youngest and oldest consumers. The perennials most frequently mentioned as favourites include echinacea, salvias, peonies, and daylilies, with ornamental grasses and garden ferns also being highly appreciated.

For producers and distributors, understanding consumer preferences is crucial for developing targeted marketing strategies and tailoring their product assortments to maximize profitability.

Mango cultivation in Northern India is crucial for the agricultural sector but faces significant challenges due to complex tree canopy structures, which hinder efficient and uniform application of agricultural treatments. This study explores the use of drone spraying technology with Ultra-Low Volume (ULV) nozzles to overcome these challenges, aiming to enhance resource efficiency and agricultural sustainability.

This research was conducted in mango orchards during the June–August 2024 growing season (during the mango flowering and early fruit-setting phase), utilizing two different types of ULV nozzles: TeeJet® 110° XR and HYPRO® ULV. These nozzles were systematically tested to assess their spray coverage and droplet penetration capabilities across various canopy layers—upper, middle, and lower. The methodology involved detailed evaluations under varying environmental conditions to measure the effectiveness of each nozzle in delivering dye, simulating the application of agrochemicals. The specific parameters measured included spray coverage area and droplet size distribution, assessed under different environmental conditions, including wind speed and humidity. The initial results highlighted the TeeJet® nozzle's superior performance in penetrating the upper and middle canopy layers, whereas the HYPRO® nozzle showed enhanced effectiveness in reaching the lower canopy. Statistical analyses, including ANOVA, revealed significant differences in spray distribution patterns based on nozzle type and canopy layer (p<0.05). Post-hoc tests identified the optimal configurations for maximizing coverage and minimizing waste.

These findings highlight the importance of customized drone spraying strategies in modern agriculture. By selecting the appropriate nozzle types and configurations, farmers can significantly improve the precision of pesticide applications, reduce resource wastage, and mitigate environmental impacts. These insights are crucial for developing drone spraying protocols that can adapt to the specific physical and environmental contours of mango orchards. This study not only contributes to the field of precision agriculture, but also supports the development of sustainable farming practices that can be adapted to other crops and regions facing similar challenges.

For optimal nitrogen (N) fertilization management in processing tomatoes, Nitrogen Enhanced-Efficiency Fertilizers (N-EEFs) can help regulate N availability in the soil, synchronize it with plant demand, and reduce the risk of N leaching. Within the Agritech project Task 3.2.2, two N-EEFs with different modes of action were selected to determine their effect on processing tomato growth, yield, and quality, as well as on N-leaching risks. These N-EEFs were AGROCOTE 44 2-3m (44% N, controlled release) and NUTRITEC 46 (46% N, with nitrification inhibitor).

Processing tomato (cv. HEINZ 5108) was transplanted on May 25, 2024, and four treatments were compared using a complete-block design with three replicates: the two abovementioned N-EEFs together with two controls, i.e., an unfertilized control and a control fertilized with urea. All fertilizers were broadcast at transplanting at a dose of 200 kg N ha-1. Growth analyses were performed by sampling plants every 10–14 days from about 1 month after transplanting until the final harvest. N crop status was monitored at each sampling by a chlorophyll meter (SPAD-502, Minolta), sap nitrate meter (LAQUAtwin, Horiba), and a portable multispectral radiometer (Rapidscan CS-45). Plots were equipped with suction cup lysimeters to monitor the N leaching risk at 0.6 m depth.

Preliminary results suggest that N-crop status, plant growth, and yield were similar in the different fertilized treatments. On average, the aboveground biomass of fertilized treatments was approximately 8.5 t ha−1 (dry weight), while the marketable fruit yield was 58 t ha−1 (fresh weight). For fruit quality parameters, no significant differences were observed among treatments, although °Brix from EEF treatments was generally lower (on average 4.1 °Brix) than that for the urea (5.0 °Brix) and unfertilized treatments (4.8 °Brix). Concerning N-leaching, preliminary lysimeter data showed that cumulative N leaching over the crop cycle did not differ significantly among treatments. Future research will focus on replicating this experiment in spring 2025 to further investigate the effects of N-EEFs on processing tomato growth, yield, and nitrogen leaching.

Modifying the light spectrum that plants are exposed to may be an optimal strategy to balance growth, yield, and the accumulation of antioxidant compounds, particularly in lettuce plants since it is one the most economically important vegetables worldwide due to its high consumption and export. The purpose of this study was to evaluate the impact of ambient light enrichment with different LED light spectra on biomass, the relative index of chlorophyll concentration (RICC), polyphenol concentration, and the relative gene expression of enzymes associated with their formation in young green 'Levistro' lettuce leaves grown in an NFT hydroponic system under greenhouse conditions. Ambient light was enriched with blue (B), white (W), red-blue (RB), and red (R) LED lights for 14 days. Each lamp was mounted on a 120 × 35 cm thin wooden panel which shaded the experimental unit, resulting in a mean daily light integral (DLI) of 14.0 mol m⁻² d⁻¹. The control was ambient greenhouse light (DLI = 21.8 mol m⁻² d⁻¹). Fresh weight was similar across the enrichment treatments and the control, while dry matter (%) significantly decreased under B compared to the control, by 5.7%. The number of leaves increased significantly under RB compared to the control, by 24.4%. RICC rose as the plants grew, with no significant difference between the enrichment treatments and the control. Chlorogenic acid (ChlAc) concentration was significantly higher under RB compared to R, B, and W, by 136.4%, 116.7%, and 62.5%, respectively. Meanwhile, total quercetin (TQ) concentration was significantly higher under W and RB compared to the control, by 81.0% and 71.4%, respectively. Interestingly, the expression of the coumarate 3-hydroxylase (C3H) gene, associated with ChlAc formation, was higher under RB compared to the control and the other enrichment treatments, while the expression of the flavonol synthase (FLS) gene, which is linked to quercetin formation, increased under W and RB compared to the control and the other light enrichment treatments. Therefore, the modulation of the environmental light spectrum with a lower DLI than the control allowed for the maintenance of normal and adequate morphology and growth of green lettuce 'Levistro,' while RB promoted the concentration of ChlAc and TQ by increasing the expression of the C3H and FLS genes, respectively.

Keywords: LED light; greenhouse; agronomic characteristics; polyphenol; gene expression

Jujube (Ziziphus mauritiana L.) holds untapped potential for morphological and biochemical diversity, yet their adaptation and performance under medium lowland agroecosystems remain underexplored. This study aimed to evaluate the genetic diversity, morphological traits, yield-related traits, and biochemical composition of 19 jujube genotypes to identify superior genotypes suitable for medium lowland conditions, typically utilised for irrigated rice cultivation in Cumilla, Bangladesh. The research was conducted over two consecutive growing seasons (2022-2023 and 2023-2024) and focused on assessing yield and biochemical components to determine overall genotype performance and adaptability. Genetic parameters such as the genetic coefficient of variation (GCV), phenotypic coefficient of variation (PCV), heritability, genetic advance (GA), and genetic advance as a percentage of the mean (GA%) were analysed to quantify trait variability and selection potential. Notably, fruit length, fruit width, fruit weight, pulp weight, and vitamin C concentration exhibited high heritability and substantial GA, indicating their potential for genetic improvement. Correlation analyses revealed significant relationships between morphological and biochemical traits, with fruit size and weight positively correlated with total soluble solids (TSSs) and soluble sugars, whereas a negative correlation was observed with non-reducing sugar. Furthermore, fruit weight, pulp weight, juice weight, and TSSs were identified as key determinants for selecting high-yielding genotypes. Multivariate analyses, including hierarchical clustering, cluster mean evaluation, principal component analysis biplots, and heatmaps were employed to identify genotype groupings and trait-specific contributions and obtain variability for superior genotype selection. Among the evaluated genotypes, Ball Sunduri and Local Kul-4 demonstrated high performance in both yield and biochemical composition, making them suitable for cultivation in medium lowland agroecosystems. This study provides a nuanced understanding of the relationship between genetic diversity and environmental factors, contributing to the optimisation of jujube cultivation in diverse agroecological settings. By demonstrating the feasibility of medium lowlands as an alternative agroecosystem for high-value jujube production, this research paves the way for innovative land-use strategies and climate-resilient agricultural practices.

Drought is one of the most relevant abiotic stresses that currently affect horticultural species, and it is mostly due to climate change. The negative effects of water shortage are mostly significant for high-water-demanding crops, such as tomato (Solanum lycopersicum L.), and they can occur as morphological, physiological, and biochemical alterations. Nowadays, biostimulants are considered a emerging key strategy for enhancing plant productivity and resilience to abiotic stresses, including drought.

The main goal of this work is to evaluate the effects of new foliar biostimulants on the physiological and biochemical properties of tomatoes (leaves and fruits) grown under water stress conditions in an open field.

Tomato plants (cv. ‘Heinz 1301’) were arranged on three experimental rows in open field conditions, each of which was subjected to three different irrigation (I) regimes: 100% (I-100), 60% (I-60), and 30% (I-30) of IRRIFRAME recommendations. The biostimulants were distributed by spraying directly onto the leaves: non-fermented kiwi residual biomasses (T2), kiwi residual biomasses fermented with Lactiplantibacillus plantarum 4193 (T3), and kiwi residual biomasses fermented with Companilactobacillus farciminis 4841 (T4). Control plants (T1) were sprayed with water only. Plant health was assessed after fruit colour change (R1, five weeks from the start of stress) and fruit ripening (R2, eight weeks from the start of stress), measuring leaf colour and SPAD index. At both R1 and R2, leaf samples were collected and analysed for their chlorophylls, polyphenols, total antioxidant content (DPPH assay), and proline content. Fruits were harvested when fully ripe, characterized by size and analysed biochemically (polyphenol, lycopene, and soluble sugar content; titratable acidity; and antioxidant activity).

Severe water stress (I-30) caused an increase in leaf SPAD index (R1), a reduction in a* (redness) colour coordinates (R1 and R2), and a decrease in the total chlorophyll content (R1 and R2). This latter negative effect was reduced by all biostimulants. Leaves counteract drought stress by increasing their total polyphenols (R2) and proline content (R1) (only I-30), and no positive effect was detected for any treatments.

The reduction in fruit weight and size was observed under severe drought conditions. In I-60, an increase in the lycopene content was detected, along with a decrease in the percentage of titratable acidity and the fructose content. The use of the T3 biostimulant had a positive effect on the fruit size both in I-100 and I-60, also showing the highest content of polyphenols in I-30, in comparison with the other treatments.