Horticultural Production Systems Research Articles

Agronomic drivers of pesticide use in small-scale horticultural systems in central Mexico: cropping and farming system factors.

Abstract Horticultural Production Systems (HPS) in Mexico face challenges due to small-scale operations, limited resources, and high dependence on family labor. This study explores the use of agrochemicals in HPS and its impact on productivity and potential exposure to pesticides. Through on-farm surveys in the Morelia-Queréndaro valley, Central Mexico, factors influencing agrochemical use and toxicity were investigated. Results show that HPS configuration plays a pivotal role in predicting agrochemical use. HPS dominated by a single crop tend to use more herbicides and fertilizers, while diversified systems use fewer herbicides. Crop-specific management practices, such as row spacing and intercropping, significantly influence herbicide usage. Surprisingly, higher volumes of insecticides and fungicides do not consistently correlate with increased yields. Additionally, relationships between pesticide use and crop yields vary across onion cropping systems, emphasizing the need for tailored management strategies. We highlight the significant toxicity of insecticides and the importance of understanding factors determining their application volumes. Overall, this research underscores the complexity of agrochemical use in HPS and emphasizes the potential of diversified farming systems to reduce reliance on agrochemical inputs while maintaining productivity. These findings contribute to a deeper understanding of sustainable agriculture practices and provide valuable insights for policy makers and farm managers.

Urban food waste for soil amendment? Analysis and characterisation of waste-based compost for soil fertility management in agroecological horticultural production systems in the city of Rosario, Argentina

Urban and peri-urban lands can be an important source of food production for localised and sustainable food systems, however, their soils can be of poor quality, degraded or damaged by anthropic activities, and little is known about their suitability or safety. This paper aims to contribute to this knowledge gap by assessing the soil remediation capacity and qualities of different types of compost made from urban and peri-urban organic wastes for agroecological food production. Prepared over the course of 2021, and used in 2022 for food growing, five different composts were observed and analysed, in two different farms in the city of Rosario, Argentina. Four raw materials generated largely by local industries were used to make the composts: chicken manure, rumen (cow’s stomachs), brewer’s bagasse (byproducts of the beer industry) and urban leaves collected from the municipality waste collection. These were mixed in different proportions (all reaching the 20–30 C/N ratio, typical of quality compost) to produce viable growing substrates where radishes and lettuces were grown. The aim of the study was to assess the possibility, quality and limitations to use locally available organic inputs for soil fertility management in agroecological farming, in the context of urbanisation and to assess pathways to develop closed-cycle agroecological agriculture at metropolitan level. Natural manure substrates (raw and composted) were analysed, as well as crops grown and fertilised with each of the substrates. The attributes and limiting factors of each substrate and their response to local soil conditions were compared and physicochemical, biochemical, and microbiological analyses were performed, including among others, the study of microbial biomass, biological activity, biophytotoxicity, pH, aerobic heterotrophs, nitrogen fixation, and the presence of antibiotics, agrochemicals and heavy metals. The results of the analyses show that all the composted materials improved the physical, chemical and biological properties. However, in some cases, pollutants were present even after composting. Analysis carried out on the vegetables generally indicate undetectable levels or levels below the admissible limits, demonstrating the filtering capacity of the different composts and the soil.

An Insightful Exploration of Protected Cultivation in Horticultural Crops: A Comprehensive Review

The survey starts by examining various sorts of protected cultivation, encompassing a variety of techniques such as greenhouses, polytunnels, modern nurseries, high passages, and shade houses, as well as their benefits and constraint has emerged as a pivotal component in horticultural practices. It then, at that point, features the significance of protected cultivation in tending to worldwide food security challenges by guaranteeing all year crop creation and decreasing dependence on occasional varieties. This comprehensive review delves into the multifaceted aspects of protected cultivation in horticultural crops, aiming to provide a nuanced understanding of its impact on crop yield, quality, and resource efficiency. The audit further investigates the effect of protected cultivation strategies on the development and advancement of plant crops, including further developed crop morphogenesis, precipitation the board, and the streamlining of natural factors like temperature, moistness, and carbon dioxide levels. Besides, the usage of cutting-edge innovations like aquaculture, aeroponics, and vertical cultivating inside protected cultivation frameworks is inspected, with an accentuation on their true capacity for amplifying crop efficiency while limiting asset utilization. The article synthesizes recent advancements, challenges, and future prospects in this field, shedding light on the dynamic interplay between environmental factors, crop physiology, and technological interventions. By critically evaluating the existing literature, we present a synthesis of knowledge that can inform both researchers and farmers in optimizing protected cultivation for sustainable and resilient horticultural production systems.

The Roles of Plant-Growth-Promoting Rhizobacteria (PGPR)-Based Biostimulants for Agricultural Production Systems.

The application of biostimulants has been proven to be an advantageous tool and an appropriate form of management towards the effective use of natural resources, food security, and the beneficial effects on plant growth and yield. Plant-growth-promoting rhizobacteria (PGPR) are microbes connected with plant roots that can increase plant growth by different methods such as producing plant hormones and molecules to improve plant growth or providing increased mineral nutrition. They can colonize all ecological niches of roots to all stages of crop development, and they can affect plant growth and development directly by modulating plant hormone levels and enhancing nutrient acquisition such as of potassium, phosphorus, nitrogen, and essential minerals, or indirectly via reducing the inhibitory impacts of different pathogens in the forms of biocontrol parameters. Many plant-associated species such as Pseudomonas, Acinetobacter, Streptomyces, Serratia, Arthrobacter, and Rhodococcus can increase plant growth by improving plant disease resistance, synthesizing growth-stimulating plant hormones, and suppressing pathogenic microorganisms. The application of biostimulants is both an environmentally friendly practice and a promising method that can enhance the sustainability of horticultural and agricultural production systems as well as promote the quantity and quality of foods. They can also reduce the global dependence on hazardous agricultural chemicals. Science Direct, Google Scholar, Springer Link, CAB Direct, Scopus, Springer Link, Taylor and Francis, Web of Science, and Wiley Online Library were checked, and the search was conducted on all manuscript sections in accordance with the terms Acinetobacter, Arthrobacter, Enterobacter, Ochrobactrum, Pseudomonas, Rhodococcus, Serratia, Streptomyces, Biostimulants, Plant growth promoting rhizobactera, and Stenotrophomonas. The aim of this manuscript is to survey the effects of plant-growth-promoting rhizobacteria by presenting case studies and successful paradigms in various agricultural and horticultural crops.

Novel Energy-Saving Strategies in Apple Storage: A Review

Storing apples for up to a year is a well-established practice aimed at providing a continuous, locally produced fruit supply to consumers and adapting to market trends for optimized profits. Temperature control is the cornerstone of postharvest conservation, and apples are typically kept at temperatures ranging from 0 to 3 °C. However, the energy-intensive process of the initial cool-down and subsequent temperature maintenance poses significant financial challenges with adverse effects on the carbon footprint. Higher storage temperatures could reduce cooling-related energy usage but also pose the risk of enhanced ripening and quality loss. This work explores different storage technologies aiming to reduce energy consumption, such as 1-methylcyclopropene, ultra-low oxygen, and a dynamically controlled atmosphere with raised temperatures. The integration of advanced monitoring and control systems, coupled with data analytics and energy management, in apple storage is also discussed. These strategies can be implemented without cost-intensive construction measures in standard storage facilities. Furthermore, beneficial side effects of higher storage temperatures in terms of a reduced occurrence of storage disorder symptoms and higher maintenance of quality attributes are also discussed for this special issue on sustainable horticultural production systems and supply chains.

Application of the Lume Method to an Agroecological Horticultural System in Córdoba, Argentina

The Cordoba Green Belt, in Argentina, is a local food supply region that is reducing its surface area. Agroecology is established as a paradigm for the transformation of these agroecosystems, encompassing ecological, productive, social, cultural, and economic aspects. The Method of Economic-Ecological Analysis of Agroecosystems constitutes a proposal to evaluate the multiple aspects that intervene in decision-making in diversified family systems. In Córdoba, there are few studies that include the systematization of local information on horticultural production systems, which reflect diversity, productivity, and socio-economic impact in the agroecological transition process. The objective of the work was to evaluate the agroecological production unit of the Movement of Urban Farmers of Córdoba, from the Lume method. From the analysis of information, results were obtained that allowed sizing the production destined for self-consumption and the own production of inputs, and the great contribution of reciprocal relations. This allows valuing the non-monetary elements that give autonomy, identifying the limitations due to the high systemic costs of renting land and other services, and visualizing the gradual and sustained application of the principles of agroecology in a transition process.

The use of stinging nettle tea (Urtica sp.) to control Aulacorthum solani and Macrosiphum euphorbiae on Ranunculus asiaticus

ABSTRACT Natural and environmental-friendly approaches to control pests and diseases in horticultural production systems are showing an increasing trend. Biological alternatives, such as botanical extracts and basic substances, show promise in the reduction of the necessity for conventional plant protectants. In ornamentals, less is known about the usage, behaviour and potential of botanicals and basic substances for plant protection. In two trials, we investigated the effect of a weekly foliar spray of an aqueous extract of nettle (Urtica sp.; dried material 15 g · L–1) on two aphids, Macrosiphum euphorbiae and Aulacorthum solani. Experiments were conducted in the greenhouse with Ranunculus asiaticus as hostplant. The Urtica tea and azadirachtin (NeemAzal-T/S) as a standard used in common horticultural production were compared with the water control. Both previously infested and noninfested plants were built up to examine the effect on aphid population growth and migration. As a result, we showed that both treatments, Urtica tea and azadirachtin, reduce the aphid density significantly in comparison with the water control, although the effect of the Urtica tea was not as substantial as that of azadirachtin. Contrarily, treatments could not prevent aphid migration on previously noninfested plants. The study demonstrates that the basic substance Urtica tea can be suitable for the reduction of aphid pests in ornamental plant production, and thus, reduce the amount of synthetic plant protectants in horticulture.

Influence of Biochar Addition to Nursery Container Media: Trace Gas Efflux, Growth, and Leachate N

Abstract Biochar is a pyrolytic product generated by heating biomass in the absence of oxygen such as during bioenergy production. Biochar can be made from various feedstocks and research into its potential use in agricultural systems has examined its effects on plant growth, trace gas emissions, and N loss. However, since a paucity of work has examined biochar use in horticultural container production systems, we investigated how biochar additions to growth media impacted trace gas efflux (CO2, CH4, and N2O), plant growth, and N loss via leachate in two separate experiments: a peat-based greenhouse study using viola (Viola cornuta L. ‘Sorbet® XP Deep Orange’) and a pinebark-based outdoor study using daylily (Hemerocallis x ‘EveryDaylily Cream PBR’ L.). Biochar had little effect on viola growth, but growth inhibition was noted for daylily. Both studies clearly showed that N in leachate was reduced by biochar additions, with higher biochar rates having greater effects on reducing N loss. Reductions in N loss with biochar suggest improved N use efficiencies in agricultural systems. Biochar use also decreased N2O and CO2 fluxes in daylily, which suggests that biochar could help mitigate global climate change. Our results suggest that future studies should focus on testing lower rates of biochar in terms of growth and environmental impacts. The complexities of N management highlight the importance of developing biochar practices that increase N retention for the benefit of both agriculture and the environment. Species used in this study: viola (Viola cornuta L. ‘Sorbet® XP Deep Orange’); daylily (Hemerocallis x ‘EveryDaylily Cream PBR’ L.).

Harnessing the potential of endophytes: Sustainable solutions for enhancing forage crop resilience and soil fertility

Environmental changes pose significant challenges to sustainable agriculture, adversely affecting crop production and soil fertility. Factors such as drought, salinity, pathogens, and soil type exert their influence on the behavior of fodder crops by altering their morphological, biochemical, and molecular mechanisms, ultimately leading to reduced yields and productivity. Consequently, there is a pressing need to develop mitigation strategies aimed at enhancing the tolerance of forage crops to both biotic and abiotic stresses, addressing a critical challenge in sustaining their growth.
 In recent times, the use of biofertilizers has emerged as an environmentally friendly alternative to chemical fertilizers, holding promise for sustainable horticultural, agricultural, and forestry production systems. Notably, endophytic microorganisms play a pivotal role in promoting plant growth through direct or indirect mechanisms. Additionally, endophytic bacteria actively regulate gene expression responsible for the production of antioxidant enzymes, various phytohormones, siderophores, and ROS scavenging enzymes, all of which contribute to supporting the growth of host plants even in extreme environments. Consequently, there is a growing focus on understanding and validating the mechanisms through which beneficial plant endophytes interact to combat both biotic and abiotic stresses.
 This review emphasizes the potential of endophytes as biofertilizers, biocontrol agents, and contributors to the mitigation of abiotic and biotic stresses, all of which play crucial roles in maintaining the development of forage crops and soil fertility.

Organic Farming Practices For Horticultural Sustainability

Organic farming practices have gained attention for their potential to promote horticultural sustainability. These practices focus on ecological, economic, and social dimensions, utilizing natural processes and resources, minimizing synthetic inputs, and promoting soil fertility, biodiversity, and ecosystem health. They also reduce soil erosion, improve water retention, and mitigate environmental pollution, ensuring the long-term viability of horticultural production systems. Economically, organic farming offers both challenges and opportunities, with premium prices, reduced input costs, and improved profitability. Socially, organic farming promotes the well-being of farmers and communities, reducing exposure to harmful chemicals, and fostering collaboration and knowledge-sharing. Successful implementation requires ongoing research, extension services, and policy support to optimize the benefits of organic farming for horticultural production and global food security.

Paradigm Shift in Agricultural/ Horticultural Production System through GAP to Fill the Gap between Potential Yield and Yield Obtained

India is an agriculture-based country which is a very important and ancient enterprise of the whole world. It supplies food, fruit, vegetables, flowers to worship and decorate around the world. Apart from India there are any countries that are dependent on agriculture. It is the backbone of new industries like Sugar, Cotton etc. Krishi Vigyan Kendra, Sabour, Bhagalpur works in wide array of situations. It deals with sixteen blocks. Few blocks face flood in rainy seasons like Kharik, Naugachhia, Biharpur, Nathnagar, Sultanganj, Goradih and Gopalpur. Few of them have flood daught situations like Pirpainti, Kahalgaon, Sanhawla. Jagdishpur is the only block that always favoured that is hub of Katarni rice production. Katarni rice has GI Lag. Jardalu mango is very juicy tasty mango from Bhagapurl district also having GI tag. Due to poor management practices or there is big gaps/distances between yield and potential yield. Difference in potential yield and yield obtained is the ultimate loss of farmers. This is applied for all crops particularly for Horticultural crops. Because, horticultural crops fullfil the cash crunch of farmers. FAO has published training manual for good agricultural practices for fruit and vegetables crops. This type of manuals should be developed by different area for location specific crops. Bhagalpur has major area of mango, litchi, banana, pointed gourd, tomato. So, the manuals of good practices for these crops will be very productive to the farmers. To attain the potentiality of any crop farmers should follow the GAP (Good Agriculture of Practices) of that crop Naved Sabit et.al (2010) also and vacated for good practices of plant protection in different crops.

Building bushfire resilience in horticultural production systems: important insights from Australia

Extreme bushfire is having considerable negative effects on the sustainability of agricultural landscapes in various parts of the world. Fire-induced damages to tree crops have led to significant effects on perennial horticultural production systems with associated lower returns and decline in economic sustainability. Australia is one of the most fire-prone countries in the world and contributes to global horticultural production with production forecast level estimated at $18.2 billion in 2023–24, according to the Australian Department of Agriculture, Fisheries and Forestry. Bushfire-related damages to horticultural production may however threaten this promising potential. This review provides a commentary on the history, scale and impacts of extreme bushfires in Australia. The effects of bushfire on horticulture, including soil nutrient availability, fruit tree physiology and carbohydrate sink-source dynamics are discussed. Given the increasing frequency and severity of bushfires as a result of climate change, the negative effects of heat and fire damage on fruit tree production are expected to increase. Based on the Australian experience with bushfires in horticultural landscapes, this review outlines proactive responses for minimising bushfire impacts on horticultural production in temperate regions, with particular reference to the Rosaceae family. Adaptation strategies must be planned and set up before orchard establishment and should include defensible space or safety zones around the orchard, as well as internal and external fuel reduction strategies for the orchard lifespan.

A comparison of consistent UV treatment versus inconsistent UV treatment in horticultural production of lettuce

UV radiation is an underrated radiation currently missing in many horticultural production systems of vegetables in protected cultivation. It can be added e.g., in LED light sources. Using lettuce as a model plant, this study determined whether the use of UVB LEDs is suitable (1) for use in consistent systems (indoor farming) or (2) inconsistent systems (greenhouse). Blue and red LEDs were selected as additional artificial lighting to UVB LEDs. Both approaches led to a reproducible increase of desired flavonol glycosides, such as quercetin-3-O-(6′′-O-malonyl)-glucoside or quercetin-3-O-glucuronide and the anthocyanin cyanidin-3-O-(6′′-O-malonyl)-glucoside in lettuce. The impact of the consistent UVB treatment is higher with up to tenfold changes than that of the inconsistent UVB treatment in the greenhouse. Varying natural light and temperature conditions in greenhouses might affect the efficiency of the artificial UVB treatment. Here, UVB LEDs have been tested and can be recommended for further development of lighting systems in indoor farming and greenhouse approaches.

Studies on the potential of the basic substance chitosan in managing Podosphaera pannosa on cutting roses and Erysiphe polygoni on French hydrangea

Horticultural production systems have to move forwards to an environment-friendly and sustainable plant production. Basic substances can be added to reduce the use of synthetic plant protectant in conventional plant protection strategies. Regarding the protection of ornamental plants, less is known about the usage and behaviour of these alternative strategies and components. In our study, an infection of Podosphaera pannosa and Erysiphe polygoni in two different cultivars of cutting roses and one cultivar of French hydrangea was investigated. We studied the effect of a weekly foliar treatment of the basic substance chitosan (0.05 g/m2) compared to a water control and potassium hydrogen carbonate (VitiSan, Biofa GmbH, Münsing, Germany) in both production systems. As a result, in cutting roses as well as in French hydrangea, we found a significantly decreased infected leaf area following the use of chitosan and VitiSan compared to the water control. In both treatments, we found a stronger effect in French hydrangea, compared to roses. Results also indicate that the basic substance chitosan has to be used at a low pathogen level. We present a promising approach to reduce conventional plant protectants in ornamental plant production.

A Systematic Review and Quantitative Synthesis of the Efficacy of Quaternary Ammonium Disinfestants Against Fungal Plant Pathogens.

Quaternary ammonium compounds (QACs) have been used as disinfestants in plant production systems since the late 20th century. In studies on the control of fungal pathogens in agricultural and horticultural crop production systems, the efficacy of QAC disinfestants is variable, ranging from very high to ineffective. A systematic review and meta-analysis were performed to establish and understand how pathogen- and application-related factors influenced product efficacy. The meta-analysis was based on 124 studies involving 14 fungal plant pathogen genera, eight target materials, and four generations of QAC products that contained different mixtures of active ingredients. A significant (P < 0.0001) reduction in either disease intensity or propagule viability resulted following disinfestation using QAC products. Hedges' g standardized mean difference (g̅+) across the studies was 2.16, indicating that QACs, on average, were highly effective against fungal pathogens. Heterogeneity was significant (P < 0.0001), indicating that effect sizes (g) were not representative of a common mean effect size and supported selection of a random effects model. In all, 78.5% of the observed variance consisted of variance in true effects with a high estimate of between-study variability (τ2 = 2.15). For fungal genus, subgroup g̅+ for genera Pseudonectria and Calonectria was significantly (P < 0.0038) higher than for all other genus subgroups, except Fusarium. For target materials, subgroup g̅+ for solution, cloth, plant, and metal were significantly (P > 0.0071) higher than for inorganic material or wood. For product generation, subgroup g̅+ for fifth-generation products was significantly (P > 0.0071) higher than for fourth-, third-, and second-generation products. Dose and time accounted for only 8 and 4%, respectively, of the true variance in effect sizes in the regression model dose, time, and dose-time (P = 0.0004). Genus accounted for 40 and 51% of the true variance in effect sizes in the regression models dose and genus (P = 0.0008) and time and genus (P = 0.0007), respectively. Target material accounted for 18 and 19% of the true variance in effect sizes in the regression models dose and target (P = 0.0001) and time and target (P = 0.0001), respectively. QAC product generation accounted for 24 and 21% of the true variance in effect sizes in the regression models dose and QAC generation (P = 0.0034) and time and QAC generation (P = 0.0189), respectively. These results show that the current recommended rates for dose and contact time are generally expected to result in effective disinfestation for commercial QAC products. However, the efficacy against fungal plant pathogens is likely to be influenced by the fungal genus and target being treated and the generation of the QAC product that is used for disinfestation.

Synergism and phytotoxicity: The effects of tank‐mix additives on the biological efficacy of Cu2+ against Venturia inaequalis and Podosphaera leucotricha

AbstractThe wetting behaviour of the spray and the biological efficacy of Cu2+ active ingredients in agrochemical formulations may be enhanced by tank‐mix additives. We investigated how three BREAK‐THRU® additives (BT301: biodegradable, BT133 and BT420: bio‐based and biodegradable) tank‐mixed with commercial copper preparations influenced the spray distribution, leaf uptake and biological efficacy of copper additive mixtures against apple scab and apple powdery mildew under controlled conditions. We quantified the synergetic effects of these additives in foliar applications. In addition, we determined the phytotoxic potential and evaluated their impacts on photosynthetic activity, non‐photochemical quenching and ROS activity. The additives BT301 and BT420 strongly reduced surface tension and contact angle of copper treatments. The fluorescence observations revealed that BT301 achieved better spreading of copper formulation with more complete coverage of the leaf surface than BT420 and BT133, whereas ‘coffee‐ring’ spreading was observed with BT133. The additive BT301 showed an increase in relative fluorescence area, indicating higher ROS production as a signal of intra‐cellular tissue activity. The photochemical efficiency of photosystem II (Fv/Fm) was not negatively influenced by copper or additive treatment. Thus, we observed no phytotoxic effects of copper‐additive mixtures on apple leaves at treatment doses of 4 g Cu2+ L−1. All copper treatments reduced apple scab infections significantly, by 53%–76%. Interestingly, addition of BT301 to copper preparations showed the strongest biological efficacy (83% reduction) against Venturia inaequalis, whereas addition of BT420 showed the strongest effect against Podosphaera leucotricha (89% infection reduction). The synergetic effects of additives on the biological efficacy without phytotoxic effects on plants may have potential for reducing copper loads in horticultural production systems.

Influence of Flue Gas Desulfurization Gypsum on Phosphorus Loss in Pine Bark Substrates

Flue-gas desulfurization (FGD) gypsum, a byproduct of coal-fired electrical utility plants, has been shown to effectively reduce phosphorus (P) leaching in many agricultural systems. However, its applications in horticultural production systems have been insufficiently researched resulting in limited industry adoption. To evaluate the efficacy of FGD gypsum to reduce P leaching in horticultural media, pine bark substrates were amended with FGD gypsum at 2.5, 5, and 10% (v/v). In accordance with industry practice, controlled release fertilizer (19N-3P-10K) was amply incorporated into all potting media treatments to support primary nutrient sufficiency of transplanted stock. The greatest P leaching occurred in the control substrates containing only pine bark and fertilizer. The standard pine bark substrate treatment, containing lime and micronutrients, reduced total P leaching by 35% and should be considered a best management practice. The addition of FGD gypsum at 2.5, 5, and 10% (v/v) reduced the total P collected in leachate by 47, 59, and 70%, respectively. Gypsum amendments increased potassium leachate concentrations but elevated potassium levels normalized after ~20 days. With little to no effect on substrate physical properties or pH, pine bark substrates can be amended with FGD gypsum to effectively reduce P leaching in short-term crops.

Agroecology and system approach for sustainable and resilient horticultural production

ISHS XXXI International Horticultural Congress (IHC2022): International Symposium on Agroecology and System Approach for Sustainable and Resilient Horticultural Production Agroecology and system approach for sustainable and resilient horticultural production

Efficacy of peroxygen disinfestants against fungal plant pathogens. A systemic review and meta-analysis

The peroxygen compounds, i.e. hydrogen peroxide, peracetic acid and potassium peroxymonosulfate, have been used as disinfestants in agricultural and horticultural operations for about 30 years. This systematic review was conducted to establish the overall efficacy of peroxygen compounds against fungal plant pathogens under production settings. A meta-analysis was performed to evaluate the biocidal activity of peroxygen intervention treatments compared to non-treated controls against 20 fungal genera of plant pathogens in 95 studies. The overall summary effect was a high Hedges' g value of 3.48 with 95% confidence limits of 3.02–3.93 (P < 0.0001) for the random effects model. This observation indicated that use of peroxygen compounds, in most cases, resulted in a high reduction in viable propagules or disease progression. However, heterogeneity was also high with 88.9% of the total variance accounted for by true variance and a high between-study variance of 3.71. To understand what influences heterogeneity, subgroup analyses were performed on the categorical moderators, i.e. fungal genera, target materials and peroxygen active ingredients (a.i.). In addition, two-variable meta-regression analyses were performed with the continuous moderators of peroxygen dose and/or contact time and the three categorical moderators. Subgroup analyses showed differences between target materials (P = 0.0151) and peroxygen a.i. (P = 0.0101) but not between fungal genera (P = 0.1753). Meta-regression results concurred with subgroup analysis results wherein models with target materials and dose (P = 0.0119) or time (P = 0.0122) accounted for 8 and 9% of the true variance, respectively. Models with peroxygen a.i. and dose (P = 0.0067) or time (P = 0.0093) accounted for 5 and 4% of the true variance, respectively. Thus, heterogeneity was only partly explained by the moderators evaluated and a larger portion of the true variance attributed to factors not available through the systematic review. Additional factors were evident also, such as diversity of research protocol, assessment measurements, sample size and small-study bias. The results support that the current doses and contact times recommended for peroxygen compounds will generally be effective at controlling fungal plant pathogens in agricultural and horticultural production systems. Results also indicate that efficacy of peroxygen compounds against fungi can be affected by the target material being treated and the peroxygen a.i. applied and potentially by fungal genus. This analysis serves as a base reference for considering efficacy performance of peroxygen compounds in these production settings.

Insights into Circular Horticulture: Knowledge Diffusion, Resource Circulation, One Health Approach, and Greenhouse Technologies.

The integration of the circular economy in agriculture has promoted sustainable innovation in food production systems such as horticulture. The present paper illustrates how horticulture is transitioning to the circular economy. This research field’s performance approaches and trends were assessed through a bibliometric and text-mining analysis of the literature. Our findings revealed that circular horticulture is a recent research field that is constantly growing. Its approach has been neither systemic nor integrative but fragmented. Bioeconomy, urban agriculture, recycled nutrients, biochar, fertigation, and desalination have been positioned as research hotspots. Vegetables and fruits are the most studied crops. Resource circulation has focused primarily on biowaste recovery to provide benefits such as biofertilizers and linear-substrate substitutes, and on water reuse for the establishment of hydroponic systems. The One Health approach is scarcely explored and, therefore, weakly articulated, wherein the absence of assessment methodologies encompassing the health of ecosystems, animals, and people is a notable limitation. Science-policy interfaces between One Health and food systems need to be improved. Lastly, greenhouse technologies are aligned with bioenergy, sustainable materials, and sensing technologies. Challenges and directions for future research have been raised to promote the redesign of horticultural production systems, integrating long-term circularity.