Development of a low-tech bioponic method using mineralized chicken and goat droppings to produce lettuces

peer reviewedBioponics is a form of hydroponics that uses organic materials as fertilizers. This method appears to be an excellent alternative method for growing vegetables in areas with soils that are polluted, degraded or unsuitable for agriculture. It avoids the use of mineral chemical fertilizers, which are often expensive or inaccessible in more remote regions or in developing countries. Trials have been conducted since 2020 to develop a low-tech method for producing bioponic nutrient solution from chicken and goat manures. This research is done as part of the SWIM project in collaboration with Oxfam and AFAD, which aims to develop innovative and sustainable farming methods in Sahrawi refugee camps, located in Algeria (Sahara desert). Manures first underwent a microbial “digestion”, before being used as nutrient solutions to grow plants. This digestion was done in two stages: (1) first an anaerobic fermentation stage of 7 days, resulting in nutrient rich solutions, (2) followed by an aerobic mineralization stage of 21 days, via oxygenation of the solutions. Between the two, solutions were filtered and diluted based on the total mineral nitrogen concentration. The 1st trial tested a concentration of 65 mgN/L for chicken and goat manure solutions, while the 2nd trial tested two different concentrations for a chicken manure solution: 65 mgN/L and 140 mgN/L. The resulting solutions were then used on lettuce (Lactuca sativa) in bioponics, and compared to a conventional chemical solution. In term of yields, in the 1st trial, goat feces based solutions resulted in lettuces of about 50% of the fresh yields obtained with a chemical solution, while this percentage reached 70% on average for the chicken feces solution. In the 2nd trial, the two solutions of different concentrations resulted in yields similar to those with a chemical solution. In term of lettuce quality, manure based solutions overall resulted in lettuces of better nutritional quality than that of the chemical, i.e. leaves with lower nitrate concentration, and higher Ca, Mg, Fe, Mn and Zn concentrations. At the microbiological level, all lettuces were safe for consumption. These trials show that it is possible to grow quality lettuces in bioponics with a simple and low-tech method using manures. Chicken manures appear to be more suitable as fertilizers, in comparison to goat feces. However, the quantities of fertilizers used for the bioponic solution must be controlled to avoid mineral losses. Trials are carried out in refugee camps in Algeria to test and adapt the method to the local context. More generally, the principles of this technique can be developed in a more high-tech way and on a larger scale, notably as a way of recovering agricultural wastes and/or processing livestock effluents, which can be source of pollution.Systèmes d’irrigations innovants dans les camps réfugiés Sahraouis à Tindouf (Sud-Ouest de l’Algérie) (SWIM project)2. Zero hunger3. Good health and well-being11. Sustainable cities and communities5. Gender equality12. Responsible consumption and productio

Bioponics as a Promising Approach to Sustainable Agriculture: A Review of the Main Methods for Producing Organic Nutrient Solution for Hydroponics

peer reviewedHydroponics is a soilless cultivation technique in which plants are grown in a nutrient solution typically made from mineral fertilizers. This alternative to soil farming can be advantageous in terms of nutrient and water use efficiency, plant pest management, and space use. However, developing methods to produce nutrient solutions based on local organic materials is crucial to include hydroponics within a perspective of sustainability. They would also allow hydroponics to be developed in any context, even in remote areas or regions that do not have access to commercial fertilizers. This emerging organic form of hydroponics, which can be qualified as “bioponics”, typically recycles organic waste into a nutrient-rich solution that can be used for plant growth. Many methods have been developed and tested in the past three decades, leading to greatly heterogenous results in terms of plant yield and quality. This review describes the main organic materials used to produce nutrient solutions and characterizes and categorizes the different types of methods. Four main categories emerged: a “tea”-type method, an aerobic microbial degradation method, an anaerobic digestion method, and a combined anaerobic-aerobic degradation method. The advantages and drawbacks of each technique are discussed, as well as potential lines of improvement. This aims at better understanding the links between agronomic results and the main biochemical processes involved during the production, as well as discussing the most suitable method for certain plants and/or contexts

Bioponics as a Promising Approach to Sustainable Agriculture: A Review of the Main Methods for Producing Organic Nutrient Solution for Hydroponics

Hydroponics is a soilless cultivation technique in which plants are grown in a nutrient solution typically made from mineral fertilizers. This alternative to soil farming can be advantageous in terms of nutrient and water use efficiency, plant pest management, and space use. However, developing methods to produce nutrient solutions based on local organic materials is crucial to include hydroponics within a perspective of sustainability. They would also allow hydroponics to be developed in any context, even in remote areas or regions that do not have access to commercial fertilizers. This emerging organic form of hydroponics, which can be qualified as “bioponics”, typically recycles organic waste into a nutrient-rich solution that can be used for plant growth. Many methods have been developed and tested in the past three decades, leading to greatly heterogenous results in terms of plant yield and quality. This review describes the main organic materials used to produce nutrient solutions and characterizes and categorizes the different types of methods. Four main categories emerged: a “tea”-type method, an aerobic microbial degradation method, an anaerobic digestion method, and a combined anaerobic-aerobic degradation method. The advantages and drawbacks of each technique are discussed, as well as potential lines of improvement. This aims at better understanding the links between agronomic results and the main biochemical processes involved during the production, as well as discussing the most suitable method for certain plants and/or contexts

Microorganisms in aquaponics: Insights on the composition of the root microbiome of lettuces of varying age

peer reviewedAquaponics is a developing, soilless production technique combining hydroponics and recirculating aquaculture and is now spreading worldwide. Nevertheless, several aspects of aquaponics still need research. Indeed, despite being key-players in the dynamic equilibrium of aquaponic systems, microorganisms and their roles in aquaponics are still scarcely known. The aim of this study is thus to explore the microorganisms communities thriving in the root compartments of lettuce in the closed-loop aquaponic system of Gembloux Agro-Bio Tech and to focus on the differences between the microbial communities of lettuce of varying age. Therefore, root samples were collected from lettuces of five different age groups and microorganisms from the rhizoplane and from the endosphere were harvested. DNA was then extracted and sequenced on an Illumina MiSeq platform, targeting the V1-V3 region of the 16S rRNA gene. Results show that no significant difference could be noted between the different age groups despite a visible trend on the Bray-Curtis PCoA. However, significant differences in alpha- and beta-diversity could be observed between the rhizoplane and endosphere compartments. In terms of taxonomy, the composition of the root community is similar to what can be found in the literature and coherent with the previous experiments conducted in the same aquaponic system

Ecological study of aquaponics bacterial microbiota over the course of a lettuce growth cycle

peer reviewedThe study of microorganisms in aquaponics is an important topic which requires more research before exploiting the full potential of beneficial microorganisms. In this experiment, we focused on the evolution over time of the bacterial communities in four compartments of an aquaponic system i.e., the sump, the biofilter, the lettuce rhizoplane and lettuce root. We studied these communities over the course of a lettuce growth cycle via regular sampling and sequencing of the 16S rRNA gene of the collected bacteria. We also followed the physicochemical parameters of the aquaponic water throughout the experiment. Results show that a different community could be found in each compartment and that all four communities were stable throughout time and resilient to naturally occurring water parameter changes which characterize functioning aquaponic systems. Furthermore, the communities of the sump and biofilter also seem stable over the years as the pre-dominant taxa (Luteolibacter, Flavobacterium, Nitrospira) observed in our study are similar to the ones previously reported for this aquaponic system. Finally, our results provide proof for similarities between aquaponic and soil borne lettuce root communities (gammaproteobacteria, Flavobacterium, Pseudomonadaceae, Sphingomonadaceae) thus showing that aquaponics can be similar to soil production in terms of microbial life

Hemizygous variants in protein phosphatase 1 regulatory subunit 3F (<i>PPP1R3F</i>) are associated with a neurodevelopmental disorder characterized by developmental delay, intellectual disability, and autistic features

Abstract PPP1R3F (R3F) is a member of the glycogen targeting subunits (GTSs), which belong to the large group of regulatory subunits of protein phosphatase 1 (PP1), a major eukaryotic serine/threonine protein phosphatase that regulates diverse cellular processes. Here, we describe the identification of hemizygous variants in PPP1R3F associated with a novel X-linked recessive neurodevelopmental disorder in 13 unrelated individuals. This disorder is characterized by developmental delay, mild intellectual disability, neurobehavioral issues such as autism spectrum disorder, seizures, and other neurological findings including tone, gait, and cerebellar abnormalities. PPP1R3F variants segregated with disease in affected hemizygous males that inherited the variants from their heterozygous carrier mothers. We show that R3F is predominantly expressed in brain astrocytes and localizes to the endoplasmic reticulum in cells. Glycogen content in PPP1R3F knockout astrocytoma cells appears to be more sensitive to fluxes in extracellular glucose levels than in wild-type cells, suggesting that R3F functions in maintaining steady brain glycogen levels under changing glucose conditions. We performed functional studies on nine of the identified variants and observed defects in PP1 binding, protein stability, subcellular localization, and regulation of glycogen metabolism in most of them. Collectively, the genetic and molecular data indicate that deleterious variants in PPP1R3F are associated with a new X-linked disorder of glycogen metabolism, highlighting the critical role of GTSs in neurological development. This research expands our understanding of neurodevelopmental disorders and the role of PP1 in brain development and proper function.</jats:p

Situational factors shape moral judgments in the trolley dilemma in Eastern, Southern, and Western countries in a culturally diverse sample

Much research on moral judgment is centered on moral dilemmas in which deontological perspectives (i.e., emphasizing rules, individual rights and duties) are in conflict with utilitarian judgements (i.e., following the greater good defined through consequences). A central finding of this field Greene et al. showed that psychological and situational factors (e.g., the intent of the agent, or physical contact between the agent and the victim) play an important role in people’s use of deontological versus utilitarian considerations when making moral decisions. As their study was conducted with US samples, our knowledge is limited concerning the universality of this effect, in general, and the impact of culture on the situational and psychological factors of moral judgments, in particular. Here, we empirically test the universality of deontological and utilitarian judgments by replicating Greene et al.’s experiments on a large (N = X,XXX) and diverse (WEIRD and non-WEIRD) sample across the world to explore the influence of culture on moral judgment. The relevance of this exploration to a broad range of policy-making problems is discussed