Advances in Sustainable Cultivation of Horticultural Crops

1. Introduction

Horticulture is an activity with a colossal economic and social impact worldwide due to its potential to generate employment and income—particularly due to the significant labor demand throughout its production chain—and its contribution to food security and the fight against hunger, challenges intensified by population growth and climate change [1]. In 2024, global production of fruits and vegetables reached 2.13 billion tons, directly generating around 732 billion dollars and even approximately 1.3 trillion dollars when considering the entire production chain [2,3].

This sector is so economically important largely because of research efforts in various areas of agriculture. In the last decade, the field has seen important research innovations ranging from controlled-environment cultivation and process automation to the use of nanotechnology, genetic improvement, biostimulants, biological control, and the expansion of urban horticulture, including the production of microgreens [4,5,6,7].

However, all this technical progress is only rational if it is guided by the pursuit of truly sustainable horticulture, which, according to the FAO [3], must combine increasing food production with environmental preservation, actively confronting ecosystem degradation and the effects of climate change, within a balance that encompasses social, economic, and ecological dimensions.

Accordingly, there are still considerable challenges related to the rational use of inputs such as fertilizers and pesticides; innovations in more efficient irrigation systems and mitigation of water deficits in arid and semi-arid environments; the improvement of protected cultivation techniques; the integration of new technologies into sustainable, large-scale production systems and the utilization of organic waste generated by this very activity; and the recovery of degraded areas [8,9,10,11,12]. Therefore, the scientific and technological advances required for the sustainable cultivation of horticultural crops are primarily characterized by interdisciplinarity in the field of plant production, as reflected in the 16 articles published in this Special Issue, which will be briefly discussed below.

2. Overview of Published Articles

The 16 published articles in this Special Issue cover topics such as remote sensing, seed physiology, plant physiology, irrigation, nanofertilizers, and the interaction between these topics (

Table 1. A list of the contributions in this Special Issue (categorized by agricultural science subfield) and their main findings.

Contributions	Plant	Technology or Research Topic	Main Findings
1	Raspberries (Rubus idaeus) and Blackberries (Rubus fruticosus)	Evaluation of growth and production of varieties	Varieties demonstrated consistent vegetative growth and yield, with distinct seasonal fruiting patterns.
2	Cauliflower (Brassica oleracea)	Defining planting dates	Early strategic planting, with less environmental stress, maximizes cauliflower resilience and yield, with ‘Flame Star’ being the top-performing cultivar.
3	Tomato (Solanum lycopersicum)	Introducing nanoparticles and conventional sources of iron and zinc via foliar vs. deficit irrigation	Iron nanoparticles (200 mg L−1) increased fruit iron content under both full-irrigation and water deficit conditions. A conventional zinc source, under full irrigation (4.5 g L−1), increased both fruit production and fruit zinc content.
4	Green peppers (Capsicum annuum)	Introducing zinc nanoparticles (ZnONPs) via foliar and bioinoculants via soil vs. deficit irrigation	Adding ZnONPs plus Bacillus subtilis mitigates deficit irrigation, improving vitamin C and mineral nutrient (Ca, P, Mg, and Fe) content in fruits, thereby enhancing their nutritional quality index values.
5	Pomegranate (Punica granatum)	Synthesis and seed priming of silver (Ag) nanoparticles (NPs)	Direct imaging (SEM/TEM) and elemental chemical analysis (EDX/XRF/ICP-OES) provide confirmation that the AgNPs adhered to the surface and were also taken up into the seed.
6	Potato (Solanum tuberosum)	Deficit irrigation vs. application of nitrogen fertilizer	Deficit irrigation (≤20%) and nitrogen reduction are viable without yield loss, provided cultivar-specific tolerances for drought and nitrogen efficiency are accounted for.
7	Lettuce (Lactuca sativa)	Irrigation methods and light intensity	Light intensity of 400 µmol m−2 s−1 combined with non-circulating irrigation during the final 5 days before harvest improved anthocyanin content, deepened red pigmentation, and increased antioxidant activity.
8	Bell pepper (Capsicum annuum)	Irrigation methods	The optimal irrigation method consists of supplying water at a moderate rate (with 3 drippers per plant) and adjusting the irrigation end time according to the specific variety and crop vigor stage.
9	Strawberry (Fragaria × ananassa)	Hydroponics system monitoring	Closed-loop hydroponic systems with biweekly nutrient solution correction achieved strawberry yields equivalent to conventional open systems while nearly doubling nutrient use efficiency.
10	Lemon balm (Melissa officinalis)	Organic manure (poultry, sheep, and cattle) and consecutive harvests	Sheep manure improved essential oil production and quality, with the second and third harvests offering optimal compositions for industrial applications.
11	Caraway plant (Carum carvi)	Organic manure and foliar application of vitamins and yeast	Organic manure (15 ton ha−1), along with foliar vitamin B1 (100 mg L−1), enhanced plant growth, seed yield, essential oil content, and nutrient uptake.
12	Potato (Solanum tuberosum)	Adding Trichoderma asperellum to compost and vermicompost	Vermicompost, when heat-treated and enriched with T. asperellum, improved both the quantity and weight of mini tubers per plant.
13	Artichoke (Cynara cardunculus)	Using proximal and remote monitoring for distinguishing between organic and conventional plant management	An MFA fluorometer distinguished physiological differences between organic and conventional artichoke management. Remote sensing via UAS was less effective.
14	Genus Phoenix (Arecaceae)	The difference in germination between orthodox and recalcitrant varieties	Seed storage and germination in Phoenix palms are influenced more by species identity and geographic origin than by seed age.
15	Six halophytic species	Factors that affect seed germination	While salinity consistently hinders germination, targeted scarification can counteract this for species like Medicago marina and Ammophila arenaria, emphasizing the need for customized cultivation protocols.
16	Hops (Humulus lupulus)	Biological control of Verticillium spp.	Pseudomonas sp. HX1, Streptomyces luteogriseus HR40, and Streptomyces flavofungini HR77 reduced the disease severity index by 32.56%.

), reinforcing the fact that the sustainable cultivation of horticultural crops is an interdisciplinary endeavor involving different subsections of the agricultural sciences. These themes converge towards the search for solutions for sustainable cultivation in the face of challenges posed by climate change, particularly those arising from the inefficient use of resources such as water and soil in horticultural production.

In Contribution 1 (Pruteanu et al., 2025), the authors evaluate the influence of growth and production parameters on raspberries (Rubus idaeus) and blackberries (Rubus fruticosus) cultivated in Romania during different seasons, aiming to identify the most adapted and productive cultivars for the region. The authors found that raspberries showed consistent fruit production, with a peak in June–July and a slight resurgence in September, while blackberries exhibited high production in early summer, followed by a significant drop in August. In the same vein, in Dhukhuchhu et al.’s work (2025) (Contribution 2), the authors investigate planting strategies for cauliflower under variable climatic conditions. They identify the best planting times and densities to ensure sustainable and resilient production, offering practical guidelines for farmers in regions with harsh winters and short growing seasons.

The authors of Contributions 3 (Almeida et al., 2025) and 4 (Martins et al., 2024) study the effectiveness of nanoparticles containing zinc and iron and/or bio-inoculants as a method of mitigating water deficit in tomatoes and bell peppers relative to their respective conventional sources. In Contribution 3, the authors show that foliar application of iron oxide nanoparticles (NPFe₂O₃) significantly improves the physiological performance, productivity, and iron content of tomato plants. Under deficit irrigation (50% ETc), a conventional zinc source (ZnSO₄.7H₂O) promoted better crop performance. In turn, in contribution 4, the authors reveal that the combination of zinc oxide nanoparticles (nano ZnO) with bio-inoculants (plant-growth-promoting rhizobacteria) successfully mitigated the negative effects of water deficit on the nutritional quality of green bell peppers, increasing vitamin C content, total phenols, and antioxidant activity. According to the authors, a challenge in these studies remains the lack of understanding regarding the mechanisms of penetration and incorporation of nanoparticles into cells, along with their modes of action. In this regard, the authors of Contribution 5 (Alymanani et al., 2025) synthesized silver nanoparticles (AgNPs) using pomegranate peel waste and evaluated their performance as a priming agent and absorption in pomegranate seeds. The authors observed, through EDX, XRF, transmission electron microscopy imaging, and ICP-OES analyses, that the nanoparticles effectively adhered to and penetrated the pomegranate seeds.

Contributions 6 (Barka et al., 2025), 7 (Ruangsangaram et al., 2025), and 8 (Yang et al., 2025) address the issue of irrigation, although with different focuses. In Contribution 6, the authors study the possibility of reducing nitrogen (N) doses (from 165 kg ha⁻¹ to 131 kg ha⁻¹) in potato cultivars (Solanum tuberosum) as a function of irrigation depth (70%, 80%, and 100% of ETc), observing that a 20% reduction in N dose and irrigation depth generally does not harm the yield of the varieties Mesa Russet or Russet Norkotah3, while the other varieties suffer a decline in production. For the authors, these results suggest that irrigation and nitrogen inputs can be reduced without compromising productivity, but the reductions should be determined based on each cultivar. Contribution 7 refers to a study on lettuce (Lactuca sativa) in which the authors tested two light intensities (300 and 400 µmol m⁻² s⁻¹) and two irrigation systems (recirculating vs. non-recirculating), applied one week before harvest. Recirculating irrigation resulted in higher plant fresh and dry weights, regardless of light. In this study, shoot fresh weight was approximately 22% lower under non-recirculating irrigation. In Contribution 8, irrigation methods are studied in two varieties (Maldonado and Nagano) of bell pepper (Capsicum annuum), along with different cut-off times (ending 3 h before sunset and ending 4 h before sunset) and irrigation levels (two, three, and four drippers with a flow rate of 2 L h⁻¹). Irrigation had a greater impact on the yield of the Maldonado pepper. Water productivity (WP) increased with the reduction in irrigation in the May–June and November–December periods for both varieties, but the responses to cut-off times varied. The authors concluded that the ideal method for cultivating bell pepper in the northern region of South Korea is irrigation with three 2 L h⁻¹ drippers, with the cut-off time adjusted according to the variety and plant vigor.

An interesting and innovative study on hydroponic cultivation was carried out by the authors of Contribution 9 (Lim et al., 2024). In this study, two methods of correcting a nutrient solution, in a closed or open circuit, were evaluated for the cultivation of Strawberry (Fragaria × ananassa). In the first experiment, the authors controlled the system solely based on the electrical conductivity of the drained solution in an open circuit, while in experiment 2, the authors controlled the system based on the ionic composition of the drained nutrient solution, at intervals of two or four weeks, in a closed circuit. The authors concluded that there were no differences in efficiency between the systems; however, in the closed circuit, correcting the ionic composition of the solution every two and four weeks led to 94% and 88% greater nutrient efficiency, respectively, than in the open-circuit system.

Contributions 10 (Fallah et al., 2025), 11 (Hassan et al. 2025), and 12 (Peña et al. 2025) evaluate the use of organic waste, plant stimulants (Contribution 10), and beneficial microorganisms (Contributions 11 and 12). In Contribution 10, the authors study the influence of different types of manure—poultry manure (PM) (3200 kg ha⁻¹), sheep manure (SM) (5400 kg ha⁻¹), and cattle manure (CM) (6200 kg ha⁻¹)—and a control (CO) (without manure), equivalent to 100 kg N kg ha⁻¹, and harvest periods (21 June, 14 August, and 6 October 2019) on the essential oil composition of Lemon balm (Melissa officinalis), concluding that the manures significantly improved the quality of the essential oil in terms of neral and geranial percentages relative to the control. Notably, between mid-August and early October, there was a substantial increase in the levels of these valuable compounds. The authors of Contribution 11 tested doses of organic residue (0, 5, 10, and 15 tons ha⁻¹) and foliar stimulants (vitamin B1 at doses of 50 and 100 mg L⁻¹; vitamin E at doses of 50 and 100 mg L⁻¹; and active yeast at doses of 100 and 150 mL L⁻¹) on caraway plants (Carum carvi). They concluded that organic fertilization (15 tons per hectare) with foliar vitamin B₁ (100 mg L⁻¹) improved plant growth, seed production, essential oil content, and nutrient uptake. Peña et al. (2025) (Contribution 12) evaluated the effect of inoculating Trichoderma asperellum into organic compost and vermicompost as a strategy for producing seed potatoes (Solanum tuberosum). The authors concluded that vermicompost, when heat-treated and enriched with T. asperellum, improved both the quantity and weight of mini tubers per plant.

Deidda et al. (2025) (Contribution 13) conducted a study on artichokes (Cynara cardunculus), in which they used proximal and remote sensing techniques to distinguish conventional and organic farming systems in relation to plant characteristics. Remote sensing (RS) using a UAS was leveraged to assess the overall vegetative vigor of the plants through the NDVI index, capturing the entire canopy (leaves and flower heads) broadly and quickly. In contrast, MFA (proximal fluorometer) was used to analyze specific physiological parameters, such as chlorophyll, nitrogen, flavonoids, and stress, in individual leaves, allowing the detection of subtle differences between management practices. The authors observed significant physiological differences between organic and conventional artichoke cultivation. Remote sensing via an unmanned aerial vehicle proved less effective than the proximal sensor (MFA).

Contributions 14 (Obón et al.) and 15 (Castañeda-Loaiza et al.) explore the factors affecting seed germination. In Contribution 14, the authors study potential differences in the germination capacity of seeds from the genus Phoenix (Arecaceae) and their initial growth, depending on seed origin (orthodox or recalcitrant) after 10 years of storage at 5 °C. They observed that species identity and the geographic origin of the seeds influenced germination success more than seed age. Seedling development followed a conserved seasonal pattern across all species, with leaf emergence synchronized in September and between March and July, followed by winter dormancy. In Contribution 15, the effects of salinity, substrate composition, and types of dormancy breaking on the germination of six halophyte species (Mesembryanthemum crystallinum, Salicornia ramosissima, Medicago marina, Ammophila arenaria, Portulaca oleracea, and Atriplex halimus) were evaluated. The authors concluded that P. oleracea showed the highest germination rate (95.6%) in coconut fiber under irrigation with non-saline water and the shortest mean germination time (5.2 days). A. halimus did not germinate under the tested conditions. Sulfuric acid scarification improved the germination rate of M. marina by 42.2%, while ultrasound scarification improved the germination rate of A. arenaria by 35.5%.

Finally, the authors of Contribution 16 (Ghoreshizadeh et al.) tested the biological control of Verticillium spp., which causes dieback disease in hops (Humulus lupulus). They isolated bacteria from the rhizosphere and xylem of a hop plant. Six strains (three Pseudomonas from the xylem and three Streptomyces from the roots) were selected based on their in vitro antifungal activity against the pathogens Verticillium dahliae and/or V. nonalfalfae. The biocontrol potential of these strains was evaluated through plant assays in a greenhouse. The bacteria Pseudomonas sp. HX1, Streptomyces luteogriseus HR40, and Streptomyces flavofungini HR77 were the best-performing isolates, reducing the disease severity index by 32.56%.

3. Conclusions

The studies published in this Special Issue provide us with an important direction for advances in sustainable horticulture, with thematic approaches marked by interdisciplinarity but also convergence. The integration of precision technologies, such as sensing and nanotechnology, with biological practices, such as microbial control and the use of biostimulants, reveals a promising path toward optimizing water and nutritional resources, mitigating abiotic stresses, and improving product quality. The valorization of organic waste and efficient cultivation systems, such as closed-circuit hydroponics, reinforces the principle of efficient use and conservation of natural resources. Future perspectives point to the need to personalize these solutions, considering the specific responses of each cultivar and local conditions, and to deepen our understanding of new technologies’ mechanisms of action at the physiological and molecular levels. The continued synergy between basic and applied research will be fundamental to consolidating production systems that harmonize high productivity, climate resilience, and environmental and economic sustainability, combined with new advances in the fields of automation, robotics, and artificial intelligence.