Organic Greenhouse Research Articles

Nitrogen Nutrition Optimization in Organic Greenhouse Tomato Through the Use of Legume Plants as Green Manure or Intercrops

In the present study, in addition to farmyard manure (FYM), cowpea was applied as green manure and faba bean as an intercrop in an organic greenhouse tomato crop, aiming to increase the levels of soil N. Three experiments (E1, E2, E3) were carried out, in which legumes were either noninoculated or inoculated with rhizobia alone or together with plant growth, promoting rhizobacteria. Inoculation of legumes with rhizobia considerably increased N2 fixation in E1 but had no impact on N2 fixation in E2 and E3. In E1, the application of cowpea decreased yield because it imposed a stronger nematode infection as the cowpea plants acted as a good host for Meloidogyne. However, in E2 and E3 the nematode infection was successfully controlled and the legumes significantly increased the tomato yield when inoculated in E2, irrespective of legume inoculation in E3. The total N concentration in the tomato plant tissues was significantly increased by legume application in E2 and E3, but not in E1. These results show that legumes applied as green manure can successfully complement N supply via FYM in organic greenhouse tomato, while legume inoculation with rhizobia can increase the amounts of nitrogen provided to the crop via green manure.

The environmental impacts of organic greenhouse tomato production based on the nitrogen-fixing plant (Azolla)

Abstract Tomato is one of the most widely used vegetables in the world. In Canada, it is predominantly a greenhouse grown crop during the colder seasons. Hence it is necessary to study the environmental impacts of its production to improve the sustainability of greenhouse grown tomato. In this study, the organic tomato production in Quebec, Canada was conducted using life cycle assessment (LCA) method considering the cradle-to-packing system boundaries to assess environmental impacts. The system was modeled based on the value of fresh tomato at the rate of one tonne fresh product from the greenhouse and its vitamin C content represented as mg/100 g of tomato pulp. The parameters considered in the study were varying irrigation levels, and the amounts of Azolla based organic fertilizers considered, since Azolla is valued for its plant growth promoting capabilities. The results show that the production of one tonne of tomato packed had a negative-impact to human health (1.21 × 10−3 to 3.79 × 10−3 DALY), ecosystem (1.50 × 10−4 to 8.96 × 10−4 species.yr), and resources (1.89 × 10 to 3.35 × 10 $). Based on results, reduced irrigation led to increased adverse environmental impacts of production per tonne of packed tomato. However, the changes in the fertilization rate had less effect on environmental damage. The highest level of environmental damage was related to the lowest level of irrigation and the lowest level of fertilization, which mainly resulted from electricity consumption. Also, the highest level of irrigation and the lowest level of fertilization led to best environmental performance production per tonne of packed tomato. The results of this study emphasize that, although irrigation and fertilization have an important role in the performance of tomatoes and their environmental impacts, they did not significantly alter the amount of vitamin C.

Effect of Organic Fertilizer Source and Rate on Growth and Nutrient Leachate Profile of Greenhouse-grown Cucumber

Fertility management of seedlings and transplants is considered a key challenge in organic greenhouse production. This study was conducted to determine response of greenhouse-grown cucumber (Cucumis sativus) and nutrient release profile to two organic fertilizers and their combinations applied at three different concentrations in organic substrate. The organic fertilizers used were a turkey litter–based compost (TC) and a dairy manure vermicompost (VC). In addition, two control treatments [no fertilization (CK), conventional liquid fertilizer (CF)] were included. For TC, substrate leachate pH decreased for the first 17 days after addition and then increased, whereas electrical conductivity (EC), and calcium (Ca) and nitrate-nitrogen (NO3−-N) concentrations increased and then declined. For VC, EC decreased continuously over time from days 0 to 52, whereas pH increased. The Ca and NO3−-N concentrations decreased over time to 24 days and then did not change further. For TC/VC combinations, EC was stable for the first 17 days and then declined. For all organic fertilizer applications, potassium concentration was stable for the first 17 days and then decreased, whereas most of the sodium, ammonium-nitrogen, and chloride were no longer leached by 24 days. The VC and TC/VC combinations did not affect cucumber seed germination rate, seedling survival rate, seedling height, and leaf greenness (SPAD) as compared with CF. The stem length, leaf number, dry weight (DW), root index, and SPAD readings of cucumber transplants increased with increasing TC and VC fertilizer applications. The TC/VC combinations increased the biomass of cucumber transplants compared with CK, and did not differ from CF. The results of this study indicated that the 28.32 lb/yard3 of VC (high rate) or the 9.44 lb/yard3 of VC combined with 4 lb/yard3 of TC (medium rate) can be substituted for CF for the cultivation of cucumber seedlings. Based on DW, the 12 lb/yard3 of TC (high rate) or the 4 lb/yard3 of TC combined with 9.44 lb/yard3 of VC (medium rate) fertilizers were suitable replacements for CF for the cultivation of cucumber transplants.

Changes in soil macropores: Superposition of the roles of organic nutrient amendments and the greenhouse pattern in vegetable plantations

AbstractOrganic farming can potentially mitigate soil compaction, which commonly occurs in vegetable plantations, particularly in greenhouses when compared with open‐air systems. Although several studies have addressed the effect of planting patterns on soil pore characteristics, few studies have focused on changes in pore attributes under organic fertilization. We used adjacent fields during green manure planting as a control to compare the differences in soil physicochemical and macropore parameters between 14‐year‐old greenhouse plots and open‐air plots under organic fertilization. Pearson's correlation analysis was performed to analyse the drivers of soil macropore characteristics in vegetable plantations in Jiangsu Province, China. A significant increase in connectivity, fractal dimensions and total macroporosity and a decrease in bulk density after 14 years of organic farming, particularly in the surface layer in the greenhouse, were observed. However, the difference in pores in the plough pan layer was not significant between the treatments. The volume of small pores (50–500 μm) and medium pores (500–1,000 μm) increased significantly (p < 0.05) in both the greenhouse and open‐air systems, showing significantly positive relationships with soil organic matter (SOM) and total nitrogen (TN) content. Large pores (>1,000 μm) showed a clear decrease, especially in open‐air fields, possibly due to the disappearance of the original straw residues in the surface layer. Small and medium pores in the plough layer increased in greenhouse fields, whereas the opposite occurred in open‐air fields. Overall, compared with open‐air systems, long‐term organic greenhouse patterns had a significantly positive effect on soil pore attributes.

Performance and selection of tomato cultivars for organic cultivation in greenhouse

ABSTRACT Production of tomato fruits in organic systems has difficulties such as the use of adequate cultivars. The hypothesis is that organic cultivation has strength dependency of the selection of appropriate genotypes to increase the economic viability of fruit production. The present work aimed to test and obtain, under organic greenhouse system, cultivars of tomato with good fruit productivity. Tomato cultivars, hybrids and non-hybrids, were evaluated with indetermined (tutoring and stripping) and determined growth habit (free growth). In the first cultivation, we observed symptoms of nutritional deficiency in fruiting stage of tomato plants, resulting in very low productivity of fruits, with maximum of 1.8 kg/plant for the Serato hybrid. In the second year of cultivation, the additions and increases in fertilizing management increased the fruit productivity in all cultivars - in Serato, to 3.1 kg/plant, and in Predador, to 2.8 kg/plant. The hybrid Candieiro, with determined habit growth, resulted in 2.0 kg/plant of fruits. The use of hybrids with genetic resistance to some important pests and diseases, associated with increases and adequate fertilizing management, were primordial factors to increase fruit productivity in tomato under organic systems in greenhouse.

Microbial taxonomic, nitrogen cycling and phosphorus recycling community composition during long-term organic greenhouse farming.

Understanding the interplay between the farming system and soil microbiomes could aid the design of a sustainable and efficient farming system. A comparative greenhouse experiment consisting of organic (ORG), integrated (INT) and conventional (CON) farming systems was established in northern China in 2002. The effects of 12 years of organic farming on soil microbiomes were explored by metagenomic and 16S rRNA gene amplicon sequencing analyses. Long-term ORG shifted the community composition of dominant phyla, especially Acidobacteria, increased the relative abundance of Ignavibacteria and Acidobacteria Gp6 and decreased the relative abundance of Nitrosomonas, Bacillus and Paenibacillus. Metagenomic analysis further revealed that relative abundance of ammonia oxidizing microorganisms (Bacteria and Archaea) and anaerobic ammonium oxidation bacteria decreased during ORG. Conversely, the relative abundance of bacteria-carrying periplasmic nitrate reductases (napA) was slightly higher for ORG. Long-term organic farming also caused significant alterations to the community composition of functional groups associated with ammonia oxidation, denitrification and phosphorus recycling. In summary, this study provides key insights into the composition of soil microbiomes and long-term organic farming under greenhouse conditions.

APPLICATION OF ARBUSCULAR MYCORRHIZAL INOCULUM IN GREENHOUSE SOIL WITH MANURE INDUCED SALINITY FOR ORGANIC PEPPER PRODUCTION

In this study, the effect of arbuscular mycorrhizal fungus − AMF Rhizophagus intraradices inoculum (prior or with transplanting) to different pepper type (Capsicum annuum L.) cv. Arlequin F1 (long fruits) and Raiko F1 (bell pepper), on plant growth and physiological parameters in response to elevated soil P concentrations from organic greenhouse production with enhanced soil salinity, was investigated. To explain the physiological growth of mycorrhizal inoculated (M) and non-mycorrhizal inoculated (NM) plants, the parameters of fungal root length colonization, shoot concentration of P an N during growth, plant height, width of stem, yield, number of fruit per plant and also the quality parameters of fruits such as soluble solid content (SSC), fruit color, mineral profile, total soluble phenolics (TSP) and antioxidant activity (FRAP), were determined. This study showed that application of AMF in cv. Raiko cultivated in high P saline soil generally enhanced growth, fruit yield and number of fruits per plant when inoculated at planting time in the greenhouse. AM inoculated plants, regardless of the time of application in cv. Arlequin grown under the same conditions, did not have any significant differences in comparison with NM plants. Arbuscular mycorrhizal inoculation has great potential in enhancing the pepper growth and yield even in high soil P, however, because of the complexity and interaction of involved genotypes of pepper and AMF, the method and time of inoculation, the system of pepper production and environmental conditions, as well as assays have to be performed to verify positive effects.

Yield Optimization for Organic Greenhouse Cucumber Production

Yield Optimization for Organic Greenhouse Cucumber Production

Production of organic potted herbs with LED supplementary lighting, organic biostimulants and silicon

LED technology in greenhouse horticulture offers the possibility of using a blend of monochromatic light wavelengths that can stimulate or inhibit specific morphological and physiological responses and thus act as growth regulators. This is particularly interesting for organic herbs and ornamentals as few products are available to control plant morphology. Beneficial soil microorganisms or compounds such as silicon, used as biostimulants, may also play an important role in maintaining soil and plant health of organic herbs and ornamentals. Our study hypothesis was that LED supplemental lighting (SL) and biostimulants are useful tools for organic greenhouse ornamental growers to increase plant growth and product quality. By using randomized complete block designs with three to five replicates, two light treatments (with and without LED SL) were compared for 24 species and cultivars (a total of five experiments). Trials were carried out in 2016 and 2017 at Laval University (Quebec, Canada) and Les Serres Frank Zyromski (Riviere-Rouge, Canada). The photosynthetic photon flux density (PPFD) of the LED SL at the plant level was 193 µmol m(-2) s(-1) for a 12-h photoperiod (6 am to 6 pm). In experiment 4, five biostimulant treatments were also compared for four plant species or cultivars (lavender, oregano and basil ‘Harlekin’ and ‘Ajaka’): 1) Glomus intraradices applied as granules, 2) G. intraradices applied as a drench, 3) Bacillus subtilis + Bacillus amyloliquefaciens, 4) Streptomyces griseoviridis, and 5) silicon (wollastonite, CaSiO(3)). Our results showed that the shoot dry biomass (DM) of all species increased by 1.10-1.92 times under LED SL. However, no significant effect of SL was observed for plant height and width of all species/cultivars, except for one species mix (Tagetes lucida, Artemisia abrotanum, Thymus citriodorus; 17% decrease in plant height). The visual quality of plants grown under LED SL was improved for two species (lavender and basil ‘Harlekin’). All species grown in a medium enriched with wollastonite (2 g CaSiO(3) L(-1) of peat-based soil) showed 33-45% higher concentration of leaf Si when compared with control plants, although the studied species were poor Si accumulators (0.05-0.52% of leaf Si content). Notably, application of granular G. intraradices in the organic growing media of lavender and oregano increased leaf Si content by 2.88 (0.58 vs. 0.20%) and 6.59 (1.05 vs. 0.16%) times, respectively, compared with their control plants without any biostimulant. For oregano plants, S. griseoviridis treatments increased leaf Si content compared with control plants (0.35 vs. 0.16%). No significant effect of Si (at 0.05 significance level) on shoot DM was observed for any species. G. intraradices applied as granules increased DM of lavender by 15%. In conclusion, LED SL and biostimulants influenced plant growth, and for some species increased product quality of organic-grown ornamentals and herbs.

Beneficial effects of using silicon for organic greenhouse cucumber

Beneficial effects of using silicon for organic greenhouse cucumber

Climatic versus geochemical controls on soil organic matter stabilization and greenhouse gas emissions along altitudinal transects in different mountain regions

Climatic versus geochemical controls on soil organic matter stabilization and greenhouse gas emissions along altitudinal transects in different mountain regions

Effect of long-term organic fertilization on the soil pore characteristics of greenhouse vegetable fields converted from rice-wheat rotation fields

The shift from rice-wheat rotation (RWR) to greenhouse vegetable soils has been widely practiced in China. Several studies have discussed the changes in soil properties with land-use changes, but few studies have sought to address the differences in soil pore properties, especially for fields based on long-term organic fertilization under greenhouse vegetable system from RWR fields. This study uses the X-ray computed tomography (CT) scanning and statistical analysis to compare the long-term effects of the conversion of organic greenhouse vegetable fields (over one year, nine years, and fourteen years) from RWR fields on the soil macropore structure as well as the influencing factors from samples obtained in Nanjing, Jiangsu, China, using the surface soil layer and triplicate samples. The results demonstrated that the macropore structure became more complex and stable, with a higher connectivity, fractal dimension (FD) and a lower degree of anisotropy (DA), as the greenhouse vegetable planting time increased. The total topsoil macroporosity increased considerably, but the rate of increase gradually decelerated with time. The transmission pores (round pores ranging from 50 to 500μm) increased with time, but the biopores (>2000μm) clearly decreased after nine years of use as greenhouse vegetable fields. Soil organic matter (OM) has a significant relationship with the soil pore structure characteristics, especially for the transmission pores. In addition, organic fertilization on the topsoil had a short-term effect on the pores, but the effect stabilized and had a weak influence on the pores over longer periods. These results suggested that organic fertilization was conducive for controlling soil degradation regarding it physical quality for water and oxygen availability in the short term.

Processing methods of organic liquid fertilizers affect nutrient availability and yield of greenhouse grown parsley

AbstractThe demand for organic foods is increasing globally, but a key limiting factor to the production of organic greenhouse produce is the lack of certified liquid fertilizers. In this experiment, four organic fertilizers were produced using either acidic extraction, anaerobic digestion or both of ensiled biomass of organic red clover and white mustard. The resulting fertilizers were applied to greenhouse-grown parsley either alone, or in combination with nitrogen (N)-enriched water produced by flushing acidic water with ammonia, to determine their effect on plant growth and the nutrient concentrations of parsley. Six combinations of fertilizer treatments were included in the greenhouse experiment. Three treatments received either fertilizers derived from acidic extraction, anaerobic digestion or both and three treatments received fertilizers derived from acidic extraction combined with N-enriched water. Conventional inorganic liquid fertilizer, chicken manure extract and no liquid fertilizer (only water) were added as control treatments. A higher N-min (ammonium and nitrate) to potassium (K) ratio was found in fertilizers after anaerobic digestion compared to acidic extraction. All organic fertigation treatments resulted in high pH, high K and chloride concentrations and high NH4/NO3 ratios in the root zone. In addition, high electrical conductivity (EC), P, K and Mg concentrations were found when only acidic extracted fertilizers were applied. Application of plant-based organic fertilizers without amending with N-enriched water resulted in biomass yields that were 21–26% lower than the inorganic fertigation control. However, fertigation with chicken manure extract, or a combination of fertilizer derived from acidic extraction and N-enriched water, resulted in similar plant growth as inorganic fertilizer. The lower yield from fertilizer derived from acidic extraction was due to elevated EC levels in the growing medium. Our results suggest that yield of greenhouse-grown parsley using either organic fertilizers combined with N-enriched water or chicken manure extract is similar to conventional fertilizer.

Analysis of Mediterranean organic greenhouse production economics and the impact of introducing agro-ecological practices

Organic greenhouse production can be a challenge, particularly in terms of selecting agricultural practices that can sustain crop production without creating environmental or economic burdens. This study was designed to assess the economic implications of the integration of agro-ecological practices within a two-year organic greenhouse rotation programme under Mediterranean conditions. Three organic systems were compared; one was a ‘conventionalised’ system based on input substitution (SUBST) and two systems were based on agro-ecological practices associated with cover crops and different soil fertility management regimes using animal manure (AGROMAN) and compost (AGROCOM). The two-year rotation included three crops: strawberry, tomato and green bean. The results revealed better economic performance, for some aspects, of AGROMAN and AGROCOM compared with the ‘conventionalised’ organic system (SUBST) and demonstrated the economic feasibility of introducing agro-ecological practices within a two-year organic greenhouse rotation.

Detection of Bioactive Compounds in Organically and Conventionally Grown Asparagus Spears

In the recent reports, there are contradictory conclusions about the nutritional and health properties of organic and conventionally growing vegetables. We hypothesized that organic cultivation system results in higher quality of asparagus (Asparagus officinalis L.) because of organic manure and effective organisms. Therefore, new analytical methods were applied in order to find the differences in bioactive compounds between the plants growing under various cultivation systems. Total antioxidant capacities (TAC) of the conventional and organic greenhouse and conventional open-field farming of asparagus spears were determined by 2,2-azino-bis (3-ethyl-benzothiazoline-6-sulfonic acid) diammonium salt (ABTS), 1,1-diphenyl-2-picryl-hydrazyl (DPPH), and ferric-reducing antioxidant power (FRAP) assays, and UHPLC-PDA-MS was used for identification of some phenolic acids and flavonoids. Total phenolic compounds (TPC), total flavonoids, rutin, vitamin C, chlorophylls, carotenoids, and the values of TAC, determined in organic growing asparagus spears, were higher than in conventional, but not always significant. The applied for the first time FTIR spectroscopy as an estimation of the differences between the investigated samples showed more prominent bands in the region of polyphenols in organic asparagus spears than in conventional and provides a rapid and precise alternative to other methods. The binding properties of extracted polyphenols to HSA determined by 3D-fluorescence were relatively higher in organic asparagus spears than in other samples. Correlation between the amounts of total polyphenols and flavonoids and their quenching properties showed a linear relationship. All proposed analytical methods can be applied to a variety of studied plants.

Influence of different cultivation systems on bioactivity of asparagus

Evaluation of functional and bioactive compounds of Asparagus officinalis L. growing in conventional and organic greenhouse and conventional open – field farming was the aim of this research. Polyphenols in cladodes grown conventionally were higher than organic. Flavonoids and carotenoids were the highest in cladodes in open field. Organic spears were richer in total phenolics (+6.9% and +19.1%) and flavonoids (+4.7% and 16.8%) and showed higher in vitro averages of antioxidant activities by three radical scavenging assays (+12.5% and+ 22.2%) than conventional. Partial differentiation of organically and conventionally grown samples was proved by multivariate statistics. The binding properties of polyphenols to HSA were relatively high in comparison with other plants. A strong positive correlation of binding properties and bioactivity of asparagus was estimated. All new found aspects for the first time lead to recommendation of inclusion of all investigated asparagus plants into the human diet in a wider scale.

Cover crops as a part of organic greenhouse rotation: implication on soil arthropods dynamics

Cover crops as a part of organic greenhouse rotation: implication on soil arthropods dynamics

Impact of Sugarcane Bagasse Ash as an Amendment on the Physical Properties, Nutrient Content and Seedling Growth of a Certified Organic Greenhouse Growing Media

Sugarcane bagasse is the fibrous material remaining after removing the sucrose, water, and other impurities (filter mud) from the millable sugarcane. Louisiana sugarcane mills use a portion of the sugarcane bagasse to produce steam power to run equipment within the mill and/or as a boiler fuel for the clarification, evaporation, and crystallization processes. Sugarcane bagasse ash (SBA) is a by-product of the thermal conversion of the sugarcane bagasse. The purpose of this research was to investigate the use of SBA as an amendment to soilless planting media for the production of vegetable seedlings. The SBA was combined by volume with a commercial certified organic soilless growing media into 5 combinations (0%:100%, 25%:75%, 50%:50%, 75%:25%, and 100%:0%, SBA and growing media, respectively). Bean (Phaseolus vulgaris L.) var. ‘Bowie’ and Chinese kale (Brassica alboglabra) var. ‘South Sea’ were planted in each of the 5 different planting mixtures. As the percentage of SBA increased from 0% to 100%, the bulk densities increased, 0.118 to 0.712 g/cm3, while the porosity, water saturation percentage, and water at field capacity decreased. Increasing the SBA percentage significantly impacted total exchange capacity, pH, organic matter, estimated nitrogen release, and all other nutrients measured, except for sodium. The research indicates that the addition of SBA can enhance bean and Chinese kale seedling growth depending on the percentage of the ash added to the growth media. Bean and Chinese kale harvest parameters typically peaked at 25% SBA, and then decreased with increasing SBA %. Adding 25% SBA did benefit the seedling growth by providing additional nutrients for seedling growth, while reducing the cost of production by supplementing the more expensive greenhouse media by a readily available by-product of the sugarcane industry. Increasing the SBA % to 50% or greater is not recommend. Additional research is needed to determine the percentage above 25% and below 50% SBA that would still benefit seedling plant growth.

Irrigation management in organic greenhouse: how to comply with sustainability goals

Irrigation in protected cultivation is essential due to the absence of natural precipitation. High evapotranspiration, due to higher temperature and prolonged cropping period, requires ample an adequate supply of water. The water supply in a greenhouse is solely carried out by irrigation and thus enables full control over the water management of the greenhouse soil. There are no specific prescriptions for organic greenhouse horticulture (OGH) regarding water sources or irrigation. However, according to the basic principles, growers are obliged to responsibly use natural resources such as water. Thus, efficient water use and/or water recycling are important issues for organic farming. Salinity should be avoided through proper fertilisation management and the use of water sources of adequate quality. Moreover, rainwater collection is strongly encouraged or requested for operation sites situated in climatic suitable areas. Optimal and tuned irrigation is quite challenging for OGH. Obviously, supplying the crop with sufficient water is an important precondition for optimum crop health and performance. In addition, sufficient soil moisture is required for optimal functioning of the soil biota to secure mineral delivery from the applied organic amendments. Also accumulation of undesired salts must be avoided. On the other hand, nutrient leaching should be avoided or limited to a minimum. The irrigation management should take heterogeneities due to irregular water delivery of the irrigation system as well as site variations in soil and plants into account Minimizing leaching should be one of the main drivers for optimization of irrigation in OGH. Since OGH in Europe are strictly soil bound cultures, leaching and nutrient emission to groundwater is a threat. For soils with groundwater within reach of the root zone, capillary rise may add to the water supply of crops. However, irrigation strategies aiming at deficit irrigation, in other words, relying on capillary rise, can be used for the short term only. Given the presence of a surplus of ions in groundwater not only salts like Na and Cl, but also Ca, Mg, SO4 and even K, salinity problems will occur on the long run. Irrigation management tuned to crop requirements is an important issue for sustainable organic greenhouse production. To achieve sustainable management of OGH production, irrigation should be tuned to the demand of the crop, taking into account also the variations in climatic zones, soil types, growing seasons, planting dates and cultivars. Consequently, tools are required for irrigation management with the flexibility to deal with such variation. This paper will review the important aspects of the crop water demand and tools for irrigation management in organic greenhouse vegetables.

Soil fertility management in organic greenhouse: an analysis of the European context

Soil fertility management systems in organic greenhouses are quite diversified within Europe. The challenge is to identify and implement strategies which are in agreement with the organic principles stated by (EC) Reg. 834/2007 and (EC) Reg. 889/2008 as well as environmentally, socially and economically sustainable. In this paper, written by a group of scientists of different geographical origin and with different background, the state of the art of the sector and the main characteristics of the European greenhouse cropping systems are described. The main bottlenecks and constraints are discussed with a particular reference to the regulatory framework in force. The more relevant issues that may influence the enforcement and future development of the sector have been identified as specific knowledge gaps. For each of them, the appropriate research needs were elaborated in a multidisciplinary perspective as forthcoming challenges for the whole sector. Far to be exhaustive, given the wide heterogeneity of the implemented systems, this paper is able, for the first time, to give a structured outlook, on soil fertility in protected organic condition at an European scale.