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This study explores the development and validation of an airflow model to support climate prediction for Citrus Under Protective Screens (CUPS) in California. CUPS is a permeable screen structure designed to protect a field of citrus trees from large insects including the vector that causes the devastating citrus greening disease. Because screen structures modify the environmental conditions (e.g., temperature, relative humidity, airflow), farm management and treatment strategies (e.g., pesticide spraying events) must be modified to account for these differences. Toward this end, we develop a model for predicting wind speed and direction in a commercial-scale research CUPS, using a computational fluid dynamics (CFD) model. We describe the model and validate it in two ways. In the first, we model a small-scale replica CUPS under controlled conditions and compare modeled and measured airflow in and around the replica structure. In the second, we model the full-scale CUPS and use historical measurements to back test the models accuracy. In both settings, the modeled airflow values fall within statistical confidence intervals generated from the corresponding measurements of the conditions being modeled. These findings suggest that the model can aid decision support and smart agriculture solutions for farmers as they adapt their farm management practices for CUPS structures.

Stress by unfavorable environmental conditions, including temperature, light intensity, and photoperiod, significantly impact early-stage growth in crops, such as cucumber seedlings, often resulting in yield reduction and quality degradation. Advanced machine learning (ML) models combined with image-based analysis offer promising solutions for precise, non-invasive stress monitoring. This study aims to classify environmental stress symptom levels in cucumber seedlings using ML models by extracting critical color, texture, and morphological features from RGB images. In a controlled plant factory setup, two-week-old cucumber seedlings were subjected to varied environmental conditions across five chambers with differing temperatures (15, 20, 25, and 30 °C), light intensities (50, 250, and 450 µmol m−2 s−1), and day-night cycles (8/16, 10/14, and 16/8 h). A cost-effective RGB camera, integrated with a microcontroller, captured images from the top of the seedlings over a two-week period, from which sequential forward floating selection (SFFS) and correlation matrices were used to streamline feature extraction. Four ML classifiers: Support Vector Machine (SVM), K-Nearest Neighbor (KNN), Naïve Bayes (NB), and Random Forest (RF), were trained to detect stress symptoms based on selected features, highlighting that stress symptoms were detectable after day 4. KNN achieved the highest accuracy at 0.94 (94%), followed closely by SVM and RF, both at 93%, while NB reached 88%. Findings suggested that color and texture features were critical indicators of stress, and that the KNN model, with optimized hyperparameters, provided a reliable classification for stress symptom monitoring for seedlings under controlled environments. This study highlights the potential of ML-driven stress symptom detection models for controlled seedling production, enabling real-time decision-making to optimize crop health and productivity. [ABSTRACT FROM AUTHOR]

Beginning around 2013, an agri-food tech sector coalesced, proffering countless technologies that promise a more sustainable food future. Yet exactly what that future looks like varies dramatically within the sector. Based on an intensive study of this sector, we examine two paradigmatic areas of innovation—alternative protein and digital agriculture—showing how the environmental promises of each translate into very different ideal uses of space. The spatial imaginary underpinning much protein innovation is contained, aiming to bring as much production as possible into highly delimited spaces, whereas the spatial imaginary of digital agriculture is expansive, facilitating farm management at a scale far beyond what a farmer can directly experience. Such divergent technological trajectories, we argue, have always existed in food and agriculture, but they are now incongruously paired within the agri-food tech sector. In addition to being contradictory in their own terms, both wrongly conflate a spatial imaginary with socio-environmental improvement. [ABSTRACT FROM AUTHOR]

Supplementation with far-red light in controlled environment agriculture production can enhance yield by triggering the shade avoidance syndrome. However, the effectiveness of this yield enhancement can be further improved through intermittent far-red light supplementation. In this study, the effects are explored of varying far-red light photon intensities and intermittent exposure durations—specifically at 5, 15, 30, and 45 min intervals—on the growth and development of lettuce (Lactuca sativa) in plant factories, while maintaining a constant red light photon flux and daily light integral. The results showed that compared to constant far-red light, 30 min intermittent far-red light increased yield by 11.7% and the number of leaves and buds by 2.66. Furthermore, the various metrics demonstrated that intermittent far-red light supplementation enhanced the overall effectiveness of the far-red light treatment. This was validated by analyzing phytohormone content and the expression of genes related to hormone metabolism and transport at the tip of the lettuce stems. Transcriptome analysis revealed that the differences in gene expression between treatments were primarily concentrated in genes related to signaling, hormone metabolism, and transport. Weighted Gene Co-expression Network Analysis identified the co-expression modules associated with yield and quality. Additionally, dynamic expression analysis showed genes involved to far-red photoreception, response, and hormone metabolism and transport exhibited optimal rhythmic responses only under 30 min intermittent far-red light supplementation. This suggests that intermittent far-red light irradiation at 30 min intervals is the most effective for activating far-red light signaling influencing hormone metabolism and transport, thereby accelerating the growth of lettuce leaves and buds and ultimately increasing yield. [ABSTRACT FROM AUTHOR]

Simple Summary: A range of fruits and vegetables including tomatoes, cucumbers, peppers, and lettuce are grown in hydroponic systems. These systems do not contain soil and instead use a circulating nutrient solution to grow the plants. Removing soil from the growing systems changes the microscopic organisms that are present at the root of the plants. Fungi and oomycetes, a fungal-like organism, are both present in these systems. Some of these organisms promote plant growth, while others cause disease and crop loss. This paper reviews current literature on seven organisms that cause disease in plants, as well as four beneficial organisms. We explain the strategies beneficial fungi use to help plants grow, including direct killing of pathogens, strengthening the plant's immune system, and enabling the plant to gain more nutrients from the environment. Additionally, we explain how phytopathogens spread throughout hydroponic systems and destroy plant tissue. The aim of this review is to provide readers with management strategies to reduce harmful plant diseases in hydroponic operations, as well as beneficial options to increase crop yields. Both scientists and growers can benefit from a complete understanding of the interactions between plants, fungi, and oomycetes. Hydroponic systems are examples of controlled environment agriculture (CEA) and present a promising alternative to traditional farming methods by increasing productivity, profitability, and sustainability. In hydroponic systems, crops are grown in the absence of soil and thus lack the native soil microbial community. This review focuses on fungi and oomycetes, both beneficial and pathogenic, that can colonize crops and persist in hydroponic systems. The symptomatology and mechanisms of pathogenesis for Botrytis, Colletotrichum, Fulvia, Fusarium, Phytophthora, Pythium, and Sclerotinia are explored for phytopathogenic fungi that target floral organs, leaves, roots, and vasculature of economically important hydroponic crops. Additionally, this review thoroughly explores the use of plant growth-promoting fungi (PGPF) to combat phytopathogens and increase hydroponic crop productivity; details of PGP strategies and mechanisms are discussed. The benefits of Aspergillus, Penicillium, Taloromyces, and Trichoderma to hydroponics systems are explored in detail. The culmination of these areas of research serves to improve the current understanding of the role of beneficial and pathogenic fungi, specifically in the hydroponic microbiome. [ABSTRACT FROM AUTHOR]

Controlled environment farming (CEF) systems, including tunnel houses, glasshouses, and vertical farms, are expanding worldwide. As the industry scales, growers need a broader range of crops that are adapted to CEF systems to take full advantage of the potential to increase yields and decrease weather‐related risks. Dwarf grapevines (microvines) are ideal candidates for CEF due to their high economic value, phenotype, and phenology. This study aimed to develop propagation protocols, a critical first step for the successful integration of microvines in the CEF market, and to demonstrate the establishment, early growth, first flowering, and fruiting of table grape microvines in a fully indoor, LED‐lit, CEF system. An experiment was conducted to investigate the efficiency of clonal propagation of a newly developed microvine variety, which had been bred for the production of seedless table grapes in response to two variables: (a) shoot position of cutting, and (b) length of time of misting exposure (from 3 to 7 weeks). A subset of successfully established plantlets were then transplanted into a hydroponic, CEF system, where their establishment, early growth, flowering, and fruit formation were assessed. Three weeks after cuttings were taken, 83.7% of the cuttings had formed roots, regardless of cutting section or misting treatment, while the remaining 16.7% of cuttings died. The sprouting success was lower with 49.3% of plants forming new leaves after 7 weeks. The highest level of sprouting was observed with cuttings taken from mid‐shoot and lower shoot positions and the 5‐week misting duration. While the rooting efficiency and survival of green shoot microvine cuttings are very high, further research is needed to increase the frequency of sprouting in the required timeframes to levels that are more acceptable for commercial production. The establishment success of sprouted cuttings after transplanting to hydroponics was 100% and their production and fruit quality were similar regardless of cutting tissue source. The crop cycle from planting to first harvest was 208 days (63 days for plantlet production and 145 days from transplanting to first harvest). The vines began flowering after an average of 33.9 days and the berries went through veraison (i.e., commencement of ripening) after an average of 116 days under the conditions tested. Microvine fruit grown under these conditions contained greater than the minimum total soluble solids content required for the Australian market. We have demonstrated that table grape microvines have potential as a novel crop for CEF systems. [ABSTRACT FROM AUTHOR]

Abstract Horticulture in controlled environments has been increasingly used to tackle limitations on crop production. As a crucial environmental factor, light regulate plant growth and metabolism. In the present study, basil plants were subjected to different light durations and intensities considering constant daily light integral (DLI). The lighting environment included 200, 300, and 400 µmol m− 2 s− 1 intensities for 18, 12, and 9 h, respectively. DLI amounted to 12.96 mol m− 2 d− 1 among all light treatments (LI200 for 18 h, LI300 for 12 h, and LI400 for 9 h). Half of the plants under each light treatment were exposed to 30 µmol m− 2 s− 1 of far-red light. The results indicated the general negative impact of LI400/9 on the growth of basils. Exposure to far-red light hurt the growth of the shoot, while it enhanced stem and petiole elongation. This effect was due to higher gibberellin accumulation, which resulted in shade avoidance responses. Exposure to far-red light also reduced anthocyanin and flavonoid contents, as two important nutritional components. Soluble carbohydrates increased, while storage carbohydrates decreased by increasing lighting duration/decreasing light intensity or by far-red light inclusion. The lowest antioxidant activity was detected in LI400/9. In the LI200/18, the highest level of auxin and the lowest level of cytokinin were detected, while the LI300/12 exhibited the highest level of gibberellin hormone. Low light intensity and long photoperiod enhanced plant biomass and phytochemical production and are recommended for basil production in controlled environments.

Controlled environment agriculture is a promising solution to address climate change and resource limitations. Light, the primary energy source driving photosynthesis and regulating plant growth, is critical in optimizing produce quality. However, the impact of specific light spectra during night interruption on improving phytochemical content and produce quality remains underexplored. This study investigated the effects of red (peak wavelength at 660 nm) and far-red night interruption (peak wavelength at 730 nm) on photosynthetic efficiency, biomass distribution, and phytochemical production in Italian basil (Ocimum basilicum L.). Treatments included red light, far-red light, a combination of both, and a control without night interruption. Red light significantly increased chlorophyll a by 16.8%, chlorophyll b by 20.6%, and carotenoids by 11%, improving photosynthetic efficiency and nutritional quality. Red light also elevated anthocyanin levels by 15.5%, while far-red light promoted flavonoid production by 43.56%. Although red light enhanced biomass, the primary benefit was improved leaf quality, with more biomass directed to leaves over roots. Far-red light reduced transpiration, enhancing post-harvest water retention and shelf life. These findings demonstrate that red and far-red night interruption can optimize phytochemical content, produce quality, and post-harvest durability, offering valuable insights for controlled environment agriculture. Future research should focus on refining night interruption light strategies across a broader range of crops to enhance produce quality and shelf life in controlled environment agriculture. [ABSTRACT FROM AUTHOR]

The combination of increasing costs, climate change, and disease- and pestrelated issues present large challenges for the strawberry (Fragaria ×ananassa) industry in the United States. This is especially true for the Southeast, where rain, frost, and a range of foliar, fruit, and soil-borne diseases are prevalent, leading to significant losses every year. Simultaneously, niche winter markets open the opportunity to extend the harvest season, leading to an industry push to use protected culture strawberry production. Tabletop soilless strawberry greenhouse production has the advantage of avoiding soilborne issues while at the same time mitigating weather-related impacts on strawberry yield and quality. The use of long-day cultivars, originally bred for the Central Coast region of California, is currently the industry standard because of desired winter yields. However, short-day cultivars bred for Florida production might also have the potential to produce in winter. In this study, we evaluated the growth, yield, fruit chemistry, and fruit firmness of seven strawberry cultivars that are commonly grown in protected culture in North Carolina: Albion, Brilliance, Camino Real, Fronteras, Monterey, Florida Sensation, and Sweet Charlie. Experiments were conducted in a randomized complete block design in a commercial tabletop greenhouse in eastern North Carolina over two growing seasons (2022-23 and 2023-24). Our results showed that Florida cultivars Brilliance and Florida Sensation produced more consistently yields in winter compared with long-day cultivars Albion and Monterey and produced similar yields over the entire season. 'Brilliance' especially showed high fruit firmness across both years, and high sweetness in one of the two years. Additionally, the short-day cultivar Fronteras showed high yields in early spring and could serve as a late-season crop for direct-to-consumer producers. Our study showed that 'Brilliance' and 'Florida Sensation' could be alternatives to 'Albion', and that 'Monterey' can be used to produce a winter crop in a soilless tabletop production system in the Southeast. [ABSTRACT FROM AUTHOR]

Horticulture in controlled environments has been increasingly used to tackle limitations on crop production. As a crucial environmental factor, light regulate plant growth and metabolism. In the present study, basil plants were subjected to different light durations and intensities considering constant daily light integral (DLI). The lighting environment included 200, 300, and 400 µmol m− 2 s− 1 intensities for 18, 12, and 9 h, respectively. DLI amounted to 12.96 mol m− 2 d− 1 among all light treatments (LI200 for 18 h, LI300 for 12 h, and LI400 for 9 h). Half of the plants under each light treatment were exposed to 30 µmol m− 2 s− 1 of far-red light. The results indicated the general negative impact of LI400/9 on the growth of basils. Exposure to far-red light hurt the growth of the shoot, while it enhanced stem and petiole elongation. This effect was due to higher gibberellin accumulation, which resulted in shade avoidance responses. Exposure to far-red light also reduced anthocyanin and flavonoid contents, as two important nutritional components. Soluble carbohydrates increased, while storage carbohydrates decreased by increasing lighting duration/decreasing light intensity or by far-red light inclusion. The lowest antioxidant activity was detected in LI400/9. In the LI200/18, the highest level of auxin and the lowest level of cytokinin were detected, while the LI300/12 exhibited the highest level of gibberellin hormone. Low light intensity and long photoperiod enhanced plant biomass and phytochemical production and are recommended for basil production in controlled environments. [ABSTRACT FROM AUTHOR]

Blue (400–500 nm) and red (600–700 nm) light regions have been investigated for their effects on photosynthesis and plant growth, yet evidence for specific blue light wavelengths in plant research is lacking. Investigations into amber (595 nm) light are similarly limited. To 'shed light' on these two important wavelengths, this study investigated the combined effects of blue and amber light on plant growth and development in two model plants: tomato (Solanum lycopersicum cv. Beefsteak) and lettuce (Lactuca sativa cv. Breen). Plant growth responses were determined with four light treatments: B+BA (blue + broad amber, 455–602 nm), RB-NA (royal blue + narrow amber, 430–602 nm), RB-BA (royal blue + broad amber, 423–595 nm), and high-pressure sodium at a PPFD of 250 µmol m−2 s−1. After 21 days, the highest fresh and dry mass for both plant species was obtained under the RB-BA light treatment. Shifting the blue wavelength from 430 nm to 455 nm with broad amber lighting led to 40% less fresh mass for tomatoes, whereas only an approximate 5% reduction in fresh mass was observed for lettuce plants. Our findings demonstrate that an alternate and combined blue + amber light spectrum is effective for optimizing plant productivity. [ABSTRACT FROM AUTHOR]

Purpose: Our aim in this study was to examine lettuce production in vertical farming or in conventional greenhouse production in Northern European conditions from the perspective of climate change impact and environmental sustainability. Further, the goal was to identify practices and choices that could mitigate adverse effects and increase resource-use efficiency, allowing the development of more sustainable production systems. Methods: This article provides new information of the environmental impacts of lettuce production in greenhouses and vertical farming in Finland, compared using the life cycle assessment (LCA) methodology. The impact categories used were climate change impact, cumulative energy demand, resource use of fossil energy sources, resource use of minerals and metals, land use, and water scarcity. The system boundaries covered the production chains from cradle to farmgate, including inputs in production, as well as direct emissions caused by fertiliser use and the onsite composting of organic waste. The environmental impacts of the two production systems with different energy scenarios were assessed: (1) a greenhouse either with average or renewable energy; and (2) vertical farming either with average or renewable energy and with or without waste heat recovery. The data for vertical farming were based on one Finnish production site and supplementary data for the construction materials. The greenhouse data were based on a previous LCA investigation of average Finnish lettuce production. Results: The climate change and all other impact categories were lowest for lettuce produced in vertical farming with renewable energy and waste heat recovery. The climate change impact was largest for lettuce produced in greenhouse with average energy use. For energy use and energy resource use, the impacts of vertical farming were lower than greenhouse production, but for mineral and metal use and water scarcity, the impact of vertical farming was higher for average energy use without heat recovery. Direct land and irrigation water use on the production sites in Finnish circumstances represented only a small share of total land-use and water-use impacts on both production methods. Conclusion: Paying attention to the energy source and heat recovery, the environmental sustainability can be advanced in both vertical and greenhouse production systems. [ABSTRACT FROM AUTHOR]

Featured Application: The algorithms provided in this work can be applied in most scenarios where fluids and water-soluble substances, e.g., salts, are mixed to meet certain requirements. Examples include hydroponics and aquaponics. Controlled environment agriculture is a promising alternative to conventional production methods, as it is less affected by climate change and is often more sustainable, especially in circular and recycling frameworks such as aquaponics. A major cost factor in such facilities, however, is the need for skilled labor. Depending on available resources, there are endless possibilities on how to choose ingredients to realize a desired nutrient solution. At the same time, the composition of the desired solution is subject to fluctuations in fish water quality, fertilizer availability, weather, and plant development. In high-evaporation scenarios, e.g., summer, nutrient solutions might be mixed multiple times per day. This results in a complex, multi-variable task that is time-consuming to solve manually, yet requires frequent resolution. This work aims to help solve this challenge by providing methods to automate the nutrient mixing procedure. A simple mass-balance-based model of a nutrient mixing tank with connections to different water sources, drains, and fertilizers is provided. Using methods of static optimization, a program was developed which, in consideration of various process constraints and optimization variables, is able to calculate the necessary steps to mix the desired solution. The program code is provided in an open-source repository. The flexibility of the method is demonstrated in simulation scenarios. The program is easy to use and to adapt, and all necessary steps are explained in this paper. This work contributes to a higher automation level in CEA. [ABSTRACT FROM AUTHOR]

An understanding of how amendments influence the sink-to-source relationship in leafy crops can be used to optimize plant resource allocation for enhanced growth and quality. Variations in growth rates and carbon pools across individual leaves or groups of leaves at similar developmental stages allow us to comprehend plant strategies of carbon allocation and partitioning. We hypothesized that products enhancing the carbon source-to-sink relationship during leaf development can increase growth and dry matter accumulation. This project aimed to determine whether exogenous applications of a cytokinin-B-Mo-based product during the leaf development of lettuce plants impact the carbon source-to-sink relationship, thus influencing plant growth and quality. The experiment was a complete randomized design with two treatments: a negative control and the application of the product twice during the growing cycle. Each experimental unit consisted of a deep-water culture reservoir with three lettuce plants. Destructive sampling was conducted five times throughout the cycle. At each sampling time (n = 4 per experimental run), the phenological stage was determined, and measurements of root and shoot length, root and shoot dry matter, leaf length, leaf width, leaf area, chlorophyll contents, and nonstructural carbon contents were performed. These data were used to estimate growth indices. The results indicated that the cytokinin-B-Mo-based product increased the number of true unfolded leaves by 1 ± 0.4 and the overall size of the lettuce head by 9%. The treated lettuce reached marketable size 4 days earlier than that of the control treatment. Statistically significant differences were observed in shoot and root dry matter accumulation and foliar length and width at some sampling points. Some growth indices indicate an increase in leaf surface area investment and enhanced conversion efficiency of assimilates into biomass in plants treated with the product. Plants exhibiting these alterations had higher sucrose and total soluble sugar contents. There was a noticeable pattern of higher concentrations of nonstructural carbohydrates, proteins, and amino acids in the leaves compared with those in the roots across all plants and treatments. Overall, the cytokinin-B-Mo-based product appears to strengthen the source-to-sink relationship during lettuce development, resulting in a high-quality plant within a shorter timeframe.

The production of strawberries (Fragaria ×ananassa) in hydroponic systems has been increasing. In hydroponic systems, precise nutrient management is crucial for optimal plant growth and fruit production. Among essential elements, potassium (K) is a key nutrient that affects fruit yield and quality in fruiting crops. The objective of this study was to investigate whether increasing the K concentration in the Yamazaki strawberry nutrient solution could enhance plant growth, fruit yield, and fruit quality in hydroponic strawberries. Bare-root plants of strawberry ‘Monterey’ and ‘San Andreas’ were planted in a deep water culture hydroponic system and grown with initial K concentrations of 117, 194, 271, and 348 mg·L−1 under the same initial nitrogen concentration of 77 mg·L−1. As the K concentration increased from 117 to 348 mg·L−1, the nutrient solution electrical conductivity increased from 1.0 to 1.9 dS·m−1. The experiment was conducted inside an indoor vertical farm at a 23 °C air temperature with an extended photon flux density (400–750 nm) of 350 µmol·m−2·s−1 under an 18-hour photoperiod. Increasing the K concentration from 117 to 348 mg·L−1 had minimal effects on plant growth characteristics of both cultivars, although root dry mass of ‘Monterey’ increased linearly with increasing K. Increasing the K concentration from 117 to 348 mg·L−1 did not affect the total fruit number or total fruit fresh mass of ‘Monterey’, but for ‘San Andreas’, it reduced the total fruit number by 34% and total fruit fresh mass by 45%. Additionally, increasing the K concentration from 117 to 348 mg·L−1 reduced the individual fruit mass, fruit length, and fruit diameter and increased titratable acidity in both cultivars. These results indicate that increasing the K concentration in the Yamazaki strawberry nutrient solution did not benefit plant growth, fruit yield, or fruit quality of the hydroponically grown strawberries ‘Monterey’ or ‘San Andreas’.

ABSTRACT Controlled environment farming (CEF) systems, including tunnel houses, glasshouses, and vertical farms, are expanding worldwide. As the industry scales, growers need a broader range of crops that are adapted to CEF systems to take full advantage of the potential to increase yields and decrease weather‐related risks. Dwarf grapevines (microvines) are ideal candidates for CEF due to their high economic value, phenotype, and phenology. This study aimed to develop propagation protocols, a critical first step for the successful integration of microvines in the CEF market, and to demonstrate the establishment, early growth, first flowering, and fruiting of table grape microvines in a fully indoor, LED‐lit, CEF system. An experiment was conducted to investigate the efficiency of clonal propagation of a newly developed microvine variety, which had been bred for the production of seedless table grapes in response to two variables: (a) shoot position of cutting, and (b) length of time of misting exposure (from 3 to 7 weeks). A subset of successfully established plantlets were then transplanted into a hydroponic, CEF system, where their establishment, early growth, flowering, and fruit formation were assessed. Three weeks after cuttings were taken, 83.7% of the cuttings had formed roots, regardless of cutting section or misting treatment, while the remaining 16.7% of cuttings died. The sprouting success was lower with 49.3% of plants forming new leaves after 7 weeks. The highest level of sprouting was observed with cuttings taken from mid‐shoot and lower shoot positions and the 5‐week misting duration. While the rooting efficiency and survival of green shoot microvine cuttings are very high, further research is needed to increase the frequency of sprouting in the required timeframes to levels that are more acceptable for commercial production. The establishment success of sprouted cuttings after transplanting to hydroponics was 100% and their production and fruit quality were similar regardless of cutting tissue source. The crop cycle from planting to first harvest was 208 days (63 days for plantlet production and 145 days from transplanting to first harvest). The vines began flowering after an average of 33.9 days and the berries went through veraison (i.e., commencement of ripening) after an average of 116 days under the conditions tested. Microvine fruit grown under these conditions contained greater than the minimum total soluble solids content required for the Australian market. We have demonstrated that table grape microvines have potential as a novel crop for CEF systems.

Crop production system assessments can evaluate if controlled environment agriculture is feasible as compared with semi-controlled and/or uncontrolled conditions. This study assessed the growth of tomatoes (Solanum lycopersicum) in three different environmental conditions (a fully controlled greenhouse mimicking controlled environment agriculture, a semi-controlled nethouse, and an uncontrolled open space) and three nutrient applications including nutrients supplied with i) 100 % inorganic fertilizer, ii) 100 % compost, and a mixture of 50 % of i and ii to be termed as mixed fertilizer from here onward. A life cycle assessment of tomato production in the greenhouse, nethouse, and open space cultivation phases was carried out using experimental data. A life cycle directory, a holistic cradle-to-gate concept, OpenLCA software, and commercial databases were used to evaluate the experimental activities’ potential for acidification, eutrophication, global warming, human toxicity, ozone depletion, and photochemical ozone creation. The environmental conditions and nutrient applications had individual and interactive effects on plant growth variables, fruit yield, and water use efficiency. For example, under the individual effects, the fruit yield means of greenhouse (9.52 ± 2.88 Mg/ha), nethouse (14.4 ± 3.64 Mg/ha), and open space (10.9 ± 1.88 Mg/ha) were significantly (P ≤ 0.05) different from one another. Fruit yield for the mixed fertilizer treatment (14.7 ± 3.06 Mg/ha) was 22.3 % and 41.9 % higher than those of inorganic fertilizer (11.5 ± 1.86 Mg/ha) and compost (8.55 ± 2.15 Mg/ha) treatments alone. The life cycle analysis showed that the phases of the nursery and product transportation (in all 3 cultivation phases) and irrigation systems in the nethouse and open space phases were the hotspots for their environmental impact. Replacement of irrigation pumps run on government electricity is suggested with solar-powered ones for nethouse and open space. Despite lower tomato yield, a fully controlled greenhouse was considered environmentally safe and the most efficient controlled environment agriculture system (with a proper supplemental lighting system) as it can operate year-round to produce an optimum annual yield of horticultural crops in arid and humid environments of the Arabian Peninsula. The significance of this study includes i) the production of Qatar-specific experimental data that is scarce in the literature, ii) the findings that insufficient supplemental lights could lower tomato yield from a greenhouse compared to a nethouse, iii) the life cycle-based environmental burdens of crop production systems, and iv) discoveries that, for arid regions, the nethouse cultivation could serve as economically viable, energy-efficient and environment-friendly tomato production systems.

The spatial distribution and diversity of plant pathogens and other microbial communities in commercial operations is the first step in identifying critical control points where crops may be at risk of disease. Our objective was to characterize the spatial variation of oomycete pathogens and bacteria across the production system of a greenhouse producing lettuce in hydroponics. We utilized DNA metabarcoding to identify oomycetes and 16S rRNA gene sequencing of bacteria from different production stages and sample types (surfaces, solutions, and roots) collected from a commercial greenhouse producing lettuce in deepwater culture. Pythium was the genus with the highest relative abundance (41 to 100%) across all production stages. P. dissotocum was detected in most samples, except for sowing and seedling surfaces and municipal water, where P. myriotylum was the most abundant species. Oomycete communities showed distinct clustering by production stages and sample types, where sowing and seedling surfaces and municipal water were separated from the rest. Proteobacteria had the highest relative abundance in the surfaces at the sowing (98%) and seedling (85%) stages. Municipal water was the only sample with less than 20% relative abundance of Proteobacteria and dominated by Cyanobacteria. Negative correlations between Pythium and 13 bacteria genera point to potential antagonists in hydroponics that should be further studied. Mapping the spatial variation of oomycetes and bacterial communities in a commercial greenhouse indicates that production stage and sample type influence microbial composition and potentially the risk to disease.

In modern agriculture, Controlled environment agriculture (CEA) stands out as a contemporary production mode that leverages precise control over environmental conditions such as nutrient, temperature, light, and other factors to achieve efficient and high-quality agricultural production. Numerous studies have demonstrated the efficacy of manipulating these environmental factors in the short period before harvest to enhance crop yield and quality in CEA. This comprehensive review aims to provide insight into various pre-harvest practices employed in CEA, including nutrient deprivation, nutrient supply, manipulation of the light environment, and the application of exogenous hormones, with the objective of improving yield and quality in horticultural crops. Additionally, we propose an intelligent pre-harvest management system to cultivate high-quality horticultural crops. This system integrates sensor technology, data analysis, and intelligent control, enabling the customization of specific pre-harvest strategies based on producers' requirements. The envisioned pre-harvest intelligent system holds the potential to enhance crop quality, increase yield, reduce resource wastage, and offer innovative ideas and technical support for the sustainable development of CEA. [ABSTRACT FROM AUTHOR]

We investigated the growth dynamics of hydroponic lettuce (Lactuca sativa) driven by the influence that potassium (K+) has on crop growth. This study aimed to determine whether increased K+ concentrations under different daily light integrals (DLIs) in a hydroponic system will boost growth of greenhouse lettuce. This study was conducted within a controlled glass greenhouse environment with varying DLIs achieved by integrating an adaptive lighting control system over a 16-hour photoperiod. We used three K+ treatments of 200, 400, or 600 mg·L-1 K+ and six DLI lighting treatments of 11.1, 12.9, 14.6, 15.9, 16.9, and 17 mol·m-2·d-1. We found that increasing K+ did not increase shoot dry weight, leaf area, or specific leaf area with increasing DLIs. Although K+ and DLI had an interacting effect on the root dry weight fraction, leaf chlorophyll content, and quantum yield of photosystem II, the K+ treatments did not increase or decrease with increasing DLIs. The influencing factor was DLI, which led to increases in shoot dry weight and leaf area, whereas a decrease in specific leaf area was observed with increasing DLIs. Ultimately, adding supplemental concentrations of K+ did not enhance lettuce growth, nor did these effects show any increase with increasing DLIs. [ABSTRACT FROM AUTHOR]

Global fertilizer production and mismanagement significantly contribute to many harmful environmental impacts, revealing the need for a greater understanding of crop growth and nutrient uptake, which can be used to optimize fertilizer management. This study experimentally adapts first-principles microbial modeling techniques to the hydroponic cultivation of Bibb lettuce (Lactuca sativa) under nitrogen-limited conditions. Monod and Michaelis–Menten's approaches are applied to predict biomass productivity and nutrient uptake and to evaluate the feasibility of reclaimed wastewater as a nutrient source of nitrogen. Experimental and modeling results reveal significantly different kinetic saturation constants ( K s = 1.331 and K m = 17.887 mg L−1) and a corresponding cell yield strongly dependent on nutrient concentration, producing visually and compositionally distinct tissue between treatments receiving ≤ 26.2 and ≥ 41.7 m g N L−1. The resulting Monod model overestimates dry mass predictions during low nutrient conditions, and the collective results support the development of a dynamic Monod curve that is temporally dependent during the plants' lifecycle. Despite this shortcoming, these results support the feasibility of reclaiming nitrogen from wastewater in hydroponic agriculture, expecting to produce lesser biomass lettuce exhibiting healthy tissue. Furthermore, this study provides a mathematical foundation for agricultural simulations and nutrient management. [ABSTRACT FROM AUTHOR]

The spectral quality of light regulates plant growth through a variety of physiological, biochemical, and molecular processes. Earlier research on ginseng sprouts have largely focused on the impact of monochromatic lights, with limited attention to combinations with white light. The present study explored the influence of white light supplemented with different wavelengths on ginseng sprout growth at both low (30) and high (200) µmol m− 2 s− 1 PPFD intensities. Significant variations in growth were noted between the two light intensities. Specifically, the green light combination proved advantageous for enhancing both growth and photosynthesis across both intensity levels. The chlorophyll fluorescence characteristics, stomatal properties, total soluble sugars, total soluble proteins, and root activity were notably enhanced by W + G (200 PPFD) treatment. Enzymatic and non-enzymatic antioxidant activities were predominantly influenced by W + R treatments at both intensity levels. Low light, particularly, W + R (30 PPFD) and W + G (30 PPFD) significantly increased mineral content in both the shoot and root. Low light intensities positively influenced the accumulation of ginsenosides Rd, F2, and Rg1 in treatments W, W + R, and W + G, respectively while Rd2 accumulation was greatly promoted by high intensity white light treatment, W (200 PPFD). Gene expression involved in the ginsenoside biosynthesis pathway aligned with ginsenoside accumulation. Therefore, to meet the growing demand for ginseng sprouts, optimizing light quality, particularly by incorporating green or red light in conjunction with white light, might serve as a promising approach for enhancing both the quality and yield of ginseng sprouts within the controlled environment agriculture system.Key message: Under high light intensity, W + G LEDs enhanced growth and photosynthesis, while W + R LEDs boosted antioxidant activity. Conversely, at low light intensity, they boosted the minerals and ginsenosides of ginseng sprouts. [ABSTRACT FROM AUTHOR]

Bioregenerative Life Support Systems (BLSS) are a key facet of plans for long term habitats on other celestial bodies. With the Artemis program headed to the moon and SpaceX pushing towards Mars the roadmap is about 10–20 years. Therefore it is vital to consider how BLSS will work with the traditional physicochemical Environmental Control and Life Support Systems (ECLSS). Biological systems are complicated. Their inputs and outputs cannot be turned on and off the way physicochemical systems can. Therefore the accurate monitoring and prediction of these systems is fundamental to integrating the BLSS into the life support system as a whole. This paper will summarize the history of BLSS research, the system requirements for integrating a BLSS into the ECLSS, and the research needed to meet these requirements. As the world looks towards the future of humans living on other celestial bodies, there is a lot of work to do to support keeping them safe and healthy. Bioregenerative Life Support Systems have potential to provide massive support, if they are effectively integrated with the physicochemical systems. • Explores the systems requirements of physicochemical and bioregenerative systems. • Provides updated equivalent system mass estimates using LED lighting technologies. • Calculates return on investment time for bioregenerative food production. • Suggests future research directions for bioregenerative life support systems (BLSS). [ABSTRACT FROM AUTHOR]

In controlled environment agriculture, customized light treatments using lightemitting diodes are crucial to improving crop yield and quality. Red (R; 600-700 nm) and blue light (B; 400-500 nm) are two major parts of photosynthetically active radiation (PAR), often preferred in crop production. Far-red radiation (FR; 700-800 nm), although not part of PAR, can also affect photosynthesis and can have profound effects on a range of morphological and physiological processes. However, interactions between different red and blue light ratios (R:B) and FR on promoting yield and nutritionally relevant compounds in crops remain unknown. Here, lettuce was grown at 200 µmol m-2 s-1 PAR under three different R:B ratios: R:B87.5:12.5 (12.5% blue), R:B75:25 (25% blue), and R:B60:40 (40% blue) without FR. Each treatment was also performed with supplementary FR (50 µmol m-2 s-1; R:B87.5:12.5+FR, R:B75:25+FR, and R:B60:40+FR).White light with andwithout FR (Wand W+FR) were used as control treatments comprising of 72.5% red, 19% green, and 8.5% blue light. Decreasing the R:B ratio from R:B87.5:12.5 to R:B60:40, there was a decrease in fresh weight (20%) and carbohydrate concentration (48% reduction in both sugars and starch), whereas pigment concentrations (anthocyanins, chlorophyll, and carotenoids), phenolic compounds, and various minerals all increased. These results contrasted the effects of FR supplementation in the growth spectra; when supplementing FR to different R:B backgrounds, we found a significant increase in plant fresh weight, dry weight, total soluble sugars, and starch. Additionally, FR decreased concentrations of anthocyanins, phenolic compounds, and various minerals. Although blue light and FR effects appear to directly contrast, blue and FR light did not have interactive effects together when considering plant growth, morphology, and nutritional content. Therefore, the individual benefits of increased blue light fraction and supplementary FR radiation can be combined and used cooperatively to produce crops of desired quality: adding FR increases growth and carbohydrate concentration while increasing the blue fraction increases nutritional value. [ABSTRACT FROM AUTHOR]

Technology and innovation are important in mitigating the risks imposed by climate change in many areas, including agriculture and food production. Many novel and emerging agri-food technologies are marching their way to market; however, consumer perceptions are crucial to the adoption of new agri-food technologies which claim to be more sustainable than conventional growing systems. This study investigates how the sense of control, an important psychological factor for human behaviours, may interact with consumers' perceptions of new agri-food technologies, and consequently affect their attitudes towards new technologies for future food production and consumption in the age of climate change. In total, 23 focus groups (n = 117) were conducted across New Zealand using Controlled Environment Agriculture (CEA, a technology-based approach to food production that optimises growing conditions for plants through the regulation of environmental factors) as the exemplar technology for discussion. Findings reveal that, when climate change and the challenge of feeding the world sustainably were presented, CEA was accepted as a means to retain control over climate and environmental crises. Meanwhile, CEA was also speculated as a threat to consumers' sense of control concerning individual body and health, social order, and ecosystem order. To manage the disruptions that CEA may impose on perceived control, consumers may adopt different strategies to compensate for the perceived loss in their sense of control. [ABSTRACT FROM AUTHOR]

A large group of horticulture species are propagated vegetatively through shoottip cuttings harvested from stock plants and planted to form adventitious roots. Adventitious rooting leads to establishing a carbohydrate sink in the region of root regeneration that is highly dependent on energy and carbon skeletons. We hypothesized that the timing of exogenous applications of cytokinin (CK) and boron (B)-molybdenum (Mo)-based products during adventitious root development can affect the flow of sugars from leaves to sinks, carbon allocation to the adventitious roots, and the quality of rooted cuttings. During this project, we aimed to determine if the application time of a CK/B-Mo-based product during the adventitious root development of unrooted cuttings would impact the source-to-sink relationship and, hence, affect plug growth and quality. A sink-strengthening commercial product based on cytokinin, B, and Mo was applied at four plug development stages plus a negative control as follows: T1, plants without product (control); T2, sticking stage (starting 24 hours after the sticking); T3, callus formation stage; T4, root development stage; and T5, toning stage. The root and shoot lengths and dry matter, number of leaves, leaf chlorophyll content, root-to-shoot ratio (based on dry matter), and nonstructural carbohydrate contents were measured. The timing of the application of the product impacted the root development, quality of the cuttings, and nonstructural carbohydrate content. Product application during the adventitious root dedifferentiation and induction phases (T2) resulted in the shortest root and shoot lengths, lowest dry matter accumulation, lowest nonstructural carbohydrate contents, and some phytotoxicity. Application during the initiation phase (T3) resulted in greater root length, total dry matter, and total soluble sugar contents compared with the control. Application during the expression phase (T4) resulted in the largest root length and mass and the highest sucrose contents. Applying the product when the roots had grown and reached all the edges of the growing media (T5) did not have any benefits compared with the control. This study provides new insights into the application timing of exogenous CKs, B, and Mo to generate a well-toned rooted coleus cutting and potential explanations in relation to nonstructural carbohydrate metabolism. [ABSTRACT FROM AUTHOR]

The composition of horticultural substrates for soilless greenhouse cultivation directly affects the sustainability of the cropping system but has also an indirect effect through the end-of-life stage of the spent media. Biochar amendment in growing media for use as bulk material and source of nutrients may improve the sustainability of controlled-environment agriculture. Horticultural substrates were compared at the end of soilless strawberry and tomato cultivation in six trials at commercial scale. Conventional mineral wool and peat-based blends were compared with peat-reduced and peat-free organic blends with or without 10% v/v biochar amendment. Nutrients, C stability of the growing media and their value as soil improver were measured. The organic growing media had a high potential for reuse and for C storage. Spent mineral wool was significantly richer in total P, K, Mg and Ca and significantly lower in organic C content and C stability than the other blends, with a clearly lower value as soil improver than the organic blends. Biochar amendment in renewable organic blends increases their value as soil improver and their potential for reuse: addition of 10% v/v biochar in the blend significantly increased the C content (90 g C/kg dry matter higher) and the C:N ratio of the spent growing media, but not the C stability. The pH of the biochar in the growing media decreased from 9.1 to 6.2 during cultivation while CEC increased. This research illustrates the feasibility of using biomass and biochar in cascade: first as growing medium and finally as a C-rich soil improver. [ABSTRACT FROM AUTHOR]

When compared to traditional field production, controlled environment agriculture (CEA) such as greenhouses and indoor vertical farms (VF) have sustainability benefits such as reduced land use, less product transportation to consumers, improved resource and land-use efficiencies, food safety, and local food availability. Despite its potential as an environmentally beneficial complement to conventional farming, CEA has numerous issues that limits its adoption and viability as a sustainable option. This review summarizes the literature on key areas of sustainability in CEA, such as (1) sustainability challenges, (2) technologies identified to address sustainability in CEA, (3) quantification and reporting of sustainability in CEA, and (4) gaps and opportunities in addressing CEA sustainability. To filter the available literature from the databases including Web of Science, this scoping review employed a combination of the keywords "sustainability," "controlled environment agriculture," "urban farm," "vertical farm," and "indoor farm." According to the review, main obstacles in CEA were high electricity use, geographical location-related tradeoffs, and an unfavorable public perception of CEA in comparison to field production. These issues are now being addressed by optimized lighting and sensor technology, models, decision support tools to reduce electricity use, and marketing tactics to educate people about the benefits of CEA. This scoping review offers two critical areas to focus sustainability improvement efforts: lowering electrical demand and using circular techniques for organic waste and wastewater reuse in CEA to increase water, nutrient, and energy use efficiency and recovery. In addition, it discusses the techniques and approaches to sustainability assessment in CEA, particularly within the research and application contexts. This scoping review, thus, outlines strategies for enhancing sustainability in CEA, highlighting the importance of integrating circular economy principles and advanced technologies to optimize resource use, and advocates for ongoing research and education to shift public perceptions toward the sustainable potential of CEA. [ABSTRACT FROM AUTHOR]

In controlled environments (CE), temperature can be adjusted to increase anthocyanin concentration and thus improve foliage color of crops before harvest. Our objective was to quantify how end-of-production (EOP) cooling influences yield, growth, development, quality parameters, and foliage color of red leaf lettuce (Lactuca sativa). Seeds of red leaf lettuce ‘Barlach’, ‘Rouxai’, and ‘Thurinus’ were sown in a growth chamber with a mean daily temperature (MDT) set point of 22 °C, carbon dioxide (CO2) concentration of 500 µmol·mol−1, and a photosynthetic photon flux density (PPFD) of 180 µmol·m−2·s−1 provided by light-emitting diodes (LEDs). After 11 days, seedlings were transplanted into deep-flow hydroponic tanks in the same growth chamber with a CO2 concentration of 800 µmol·mol−1, day/night temperature set point of 28/21 °C (MDT of 26 °C) and under LEDs that provided a PPFD of 300 µmol·m−2·s−1 for 17 h·d−1. During the last 6 to 8 days of production, plants were either left in the same conditions or transferred to growth chambers with a constant MDT of 8, 14, 20, or 26 °C. In addition, spectrum was adjusted to a ratio (%) of 75:25 blue (400 to 500 nm):red (600 to 700 nm) (B:R) light and a PPFD of 150 µmol·m−2·s−1. EOP cooling negatively influenced shoot fresh mass (SFM) and dry mass of ‘Barlach’, ‘Rouxai’, and ‘Thurinus’. Compared with uncooled plants, the SFM and shoot dry mass (SDM) in the 14 °C EOP cooling treatment were 27% and 17% (‘Barlach’), 25% and 20% (‘Rouxai’), and 51% and 52% (‘Thurinus’) smaller, respectively. The chromametric a* value of each cultivar increased, indicating a change in color from green to red, under all EOP cooling treatments. By day 2, a* of ‘Rouxai’ and ‘Thurinus’ at 14 °C increased from −1.7 to 0.06 and from −0.99 to 1.08, respectively. By day 6 of EOP treatment, a* of ‘Barlach’ under the EOP 14 °C treatment increased from −4.18 to −1.66, whereas the a* of uncooled plants decreased from −5.06 to −6.97. Plants exposed to EOP cooling also had greater anthocyanin concentrations. At 14 °C ‘Barlach’, ‘Rouxai’, and ‘Thurinus’ possessed 62%, 53%, and 59% greater anthocyanin than the control. Foliar concentrations of magnesium, manganese, and zinc increased by 23%, 20%, and 21% in ‘Barlach’, and by 26%, 21%, and 13% in ‘Rouxai’ at 14 °C. We observed the highest concentration of violaxanthin, lutein, and total carotenoids in ‘Barlach’ at 14 °C and at 20 °C in ‘Thurinus’. Total water-soluble vitamin (WSV) concentration of ‘Rouxai’ and ‘Thurinus’ was reduced under EOP cooling. In addition, we observed altered concentrations among the WSV, such as reduced vitamin B1, but the highest concentration of vitamin B6 for each cultivar in plants exposed to EOP. Vitamin C was 24%, 29%, and 37% greater in ‘Barlach’; 19%, 23%, and 24% greater in ‘Rouxai’; and 34%, 29%, and 45% greater in ‘Thurinus’ control plants than plants exposed to 20, 14, or 8 °C, respectively.

Vertical farming is considered to be a key enabler for transforming agrifood systems, especially in or nearby urbanized areas. Vertical farming systems (VFS) are advanced indoor cropping systems that allow for highly intensified and standardized plant production. The close control of environmental parameters makes crop production stable and repeatable, ensuring year-round uniform product quality and quantity irrespective of location. However, due to continuous changes in plant physiology and development, as well as frequent changes in electricity prices, the optimum conditions for crop production and its associated costs can change within days or even minutes. This makes it beneficial to dynamically adjust setpoints for light (intensity, spectrum, pattern, and daylength), CO2, temperature, humidity, air flow, and water and nutrient availability. In this review, we highlight the beneficial effects that dynamic growth conditions can have on key plant processes, including improvements in photosynthetic gas exchange, transpiration, organ growth, development, light interception, flowering, and product quality. Our novel findings based on modeling and experimentation demonstrate that a dynamic daily light intensity pattern that responds to frequent changes in electricity prices can save costs without reducing biomass. Further, we argue that a smart, dynamic VFS climate management requires feedback mechanisms: several mobile and immobile sensors could work in combination to continuously monitor the crop, generating data that feeds into crop growth models, which, in turn, generate climate setpoints. In addition, we posit that breeding for the VFS environment is at a very early stage and highlight traits for breeding for this specialized environment. We envision a continuous feedback loop between dynamic crop management, crop monitoring, and trait selection for genotypes that are specialized for these conditions.

Supplementation with far-red light in controlled environment agriculture production can enhance yield by triggering the shade avoidance syndrome. However, the effectiveness of this yield enhancement can be further improved through intermittent far-red light supplementation. In this study, the effects are explored of varying far-red light photon intensities and intermittent exposure durations—specifically at 5, 15, 30, and 45 min intervals—on the growth and development of lettuce (Lactuca sativa) in plant factories, while maintaining a constant red light photon flux and daily light integral. The results showed that compared to constant far-red light, 30 min intermittent far-red light increased yield by 11.7% and the number of leaves and buds by 2.66. Furthermore, the various metrics demonstrated that intermittent far-red light supplementation enhanced the overall effectiveness of the far-red light treatment. This was validated by analyzing phytohormone content and the expression of genes related to hormone metabolism and transport at the tip of the lettuce stems. Transcriptome analysis revealed that the differences in gene expression between treatments were primarily concentrated in genes related to signaling, hormone metabolism, and transport. Weighted Gene Co-expression Network Analysis identified the co-expression modules associated with yield and quality. Additionally, dynamic expression analysis showed genes involved to far-red photoreception, response, and hormone metabolism and transport exhibited optimal rhythmic responses only under 30 min intermittent far-red light supplementation. This suggests that intermittent far-red light irradiation at 30 min intervals is the most effective for activating far-red light signaling influencing hormone metabolism and transport, thereby accelerating the growth of lettuce leaves and buds and ultimately increasing yield.

Light spectral composition regulates terpenoid biosynthesis, abundances, and chemical diversity in both aboveground and belowground organs, thus impacting the nutritional and medicinal content, aroma, flavor, and color of plants. Red and blue (B) light regulation of terpenoid biosynthesis is mutually dependent, and a light spectrum >50% of red (R) tends to be detrimental to the biosynthesis of various terpenoids. The transcription factor elongated hypocotyl 5 (HY5) plays a central role in UV, R, and B light signaling regulating terpenoid biosynthesis. Beside HY5, MYB and trichome-specific transcription factors play a role in UV light signaling affecting terpenoids. In controlled environment agriculture (CEA), light is used to impact terpenoid production and improve plant quality. In this review we discuss various aspects of light as important regulators of terpenoid production in different plant organs. Spectral quality primarily modifies terpenoid profiles, while intensity and photoperiod influence abundances. The central regulator of light signal transduction elongated hypocotyl 5 (HY5) controls transcriptional regulation of terpenoids under UV, red (R), and blue (B) light. The larger the fraction of R and green (G) light, the more beneficial the effect on monoterpenoid and sesquiterpenoid biosynthesis, and such an effect may depend on the presence of B light. A large fraction of R light is mostly detrimental to tetraterpenoid production. We conclude that light is a promising tool to steer terpenoid production and potentially tailor the quality of plants. [ABSTRACT FROM AUTHOR]

This 2022 study at the Kosovo Agricultural Institute in Peja evaluated innovative tomato cultivation techniques in open-field vegetable production. Five covering methods, including small plastic tunnels with black or transparent plastic mulching, were compared against traditional practices. Results revealed that tunnel variants with plastic mulching demonstrated earlier flowering, fruiting, and harvesting, accelerating early production by 3 to 12 days. Statistical analyses showed significant improvements in total tomato production, emphasizing the techniques’ effectiveness in enhancing productivity, resource efficiency, and weed control. Notably, small tunnels with mulching proved beneficial, with a 26.9% and 28.3% increase in production for black and transparent plastic mulch, respectively. The study suggests future research directions, including long-term sustainability assessments across different tomato varieties. In conclusion, soil mulching and small tunnels are crucial techniques in vegetable cultivation, contributing to increased total production, early production, and resource savings in controlled environment agriculture. [ABSTRACT FROM AUTHOR]

This two-year (2016–2017) study aims to fill in the gaps in our knowledge by looking at how hydroponic cultivation conditions affect stevia's growth, figuring out the best way to use nitrogen fertilizer and BAP to get the best yield and quality, and figuring out how well plants do in terms of stevioside and rebaudioside A content. The experiment was conducted based on a fully factorial layout in a completely randomized design with three replications. The treatments included five levels of ammonium nitrate (75, 150, 225, 300, and 375 mg/L) and four concentrations of 6-benzylaminopurine (BAP) (0, 75, 150, and 225 μM). The results showed that nitrogen use, which varied depending on the amount of BAP used, significantly influenced the growth, development, and economic performance of stevia. To determine the best treatment combination, it is important to consider the plant's economic performance, which is the dry weight of the leaves. The optimal treatment combination involved the use of 75 μM BAP and 75 mg/L of ammonium nitrate. This treatment combination produced the highest amounts of stevioside (2.17 g/plant) and rebaudioside A (0.67 g/plant), representing an increase of approximately 48% compared to the use of 75 mg/L of ammonium nitrate alone. Assuming a plant density of 100,000 plants per hectare, the application of 89 kg N/ha would result in the highest productivity of stevioside (217 kg/ha) and rebaudioside A (67 kg/ha). Higher nitrogen levels increased the proportion of leaf biomass in the plant but reduced the photosynthetic efficiency of the leaves. The results also revealed that a decrease in temperature and photoperiod can negatively impact the growth of stevia plants. The use of hydroponics allowed for a reduced use of nitrogen, making it an environmentally friendly option. [ABSTRACT FROM AUTHOR]