In the context of climate change and increasing aridification, Vachellia tortilis subsp. raddiana stands out for its remarkable ability to adapt to Morocco’s arid environments. It mobilizes physiological and biochemical mechanisms that strengthen its resilience to water stress. This study examines its responses to drought and highlights the potential of exploiting its bioactive compounds. Under severe water deficit, relative water content decreases from 62 ± 3% to 38 ± 2%, while proline increases from 0.8 ± 0.1 to 2.8 ± 0.3 µmol/g DM and soluble sugars rise from 12.3 ± 1.5 to 32.8 ± 2.1 mg/g DM, ensuring effective osmotic adjustment and the maintenance of cellular homeostasis. At the same time, chlorophyll a and b contents decrease by 46% and 30%, respectively, indicating an adaptive regulation of the photosynthetic apparatus. Beyond these physiological strategies, the leaves of Vachellia tortilis subsp. raddiana respond to environmental stresses through the remarkable accumulation of secondary metabolites, contributing both to defense and functional potential. They exhibit high concentrations of polyphenols (281 ± 1.2 mg GAE/g DM) and flavonoids (57.5 ± 0.9 mg QE/g DM), conferring notable antibacterial activity of leaf extracts against Escherichia coli (9 ± 1.1 to 12 ± 1.4 mm) and Staphylococcus aureus (12 ± 1.4 to 17 ± 1.3 mm). These findings highlight the dual value of the species: a model of physiological resilience and a promising resource for the sustainable development of crops adapted to arid regions under climate change.

Water stress keeps increasing considerably due to climate change. Alternative solutions, such as improving soil water retention, have become imperative in order to maintain crop productivity in arid and semi-arid areas. This study focused on the use of two types of hydrogel to improve soil properties and enhance plant tolerance to drought conditions. The first type is a synthetic, commercially available hydrogel based on sodium polyacrylate, while the second is a hydrogel produced in our laboratory from carboxymethylcellulose and sodium alginate (CMC/SA). The two hydrogels were characterized regarding their physicochemical properties, including swelling capacity and biodegradability, and their effect on lettuce plants subjected to water stress was evaluated.

The results showed that the SAP hydrogel has a high swelling capacity (228.5 g/g) compared to CMC/SA (28.1 g/g). As for biodegradability, it was low in the synthetic hydrogel (26.52%) compared to the CMC/SA hydrogel (51.01%). Furthermore, the physiological, biochemical, and morphological parameters of lettuce plants under water stress showed greater improvement following treatment with the CMC/SA hydrogel compared to SAP treatment. These improvements suggest that the bio-hydrogel not only supports better water retention but also enhances the plant’s resilience mechanisms.

These findings underscore that bio-hydrogels derived from CMC and SA offer an eco-friendly and efficient strategy to improve plant tolerance to drought stress without adverse environmental impacts. Thus, the use of natural polymer-based hydrogels could represent a sustainable alternative for agricultural practices in water-limited environments.

Legume crops, such as common bean (Phaseolus vulgaris L.), are significant in many Sub-Saharan African (SSA) countries including Eswatini, due to their numerous health benefits, high protein, fiber, vitamins, and minerals. Common beans are a staple food in many parts of the world and play a crucial role in nitrogen fixation, thereby improving soil fertility. However, climate change poses a significant threat to global food security and agricultural productivity. Eswatini's production declined due to drought, resulting in 700 metric tons in 2016 and 582.5 metric tons in 2023, falling far short of its 7,370 metric ton annual consumption, causing a supply deficit. The declines in common bean production compelled the country to rely on imports to meet local demand. The aim of this study was to assess the symbiotic performance and carbon accumulation of 27 common bean genotypes grown under field conditions. The experiment was conducted during the 2023/2024 cropping season. A Randomized Complete Block Design was used to test 27 common bean germplasms (11 red speckled sugar and 16 red mottled). The beans were planted in 13.5 m² plots (4.5 m × 3.0 m) with 50 cm inter-row and 10 cm intra-row spacings. Each plot consisted of 4 rows, with 20 plants per row. The data revealed significant differences among genotypes, with Cim-Rm-36 exceling in growth with 47.43 g.plant^-1 shoot dry matter yield and 1927.07 mg.plant^-1 carbon content, and Mwctz20a-Rm19 showing strong nitrogen fixation with 155.73 kg.ha^-1 of N-fixed. Genotype Mwctz20a-Rm-4 had the highest grain yield (1747.39 kg.ha^-1), showing high productivity potential, while Cim-Rm-14-Als61 had the highest nitrogen concentration (3.50%), indicating efficient nitrogen uptake. The δ13C values (-27.38‰ to -28.06‰) suggested similar water use efficiency among genotypes. The finding showed that common bean can make a significant contribution to N fertility, with carbon accumulation highlighting the potential for selecting genotypes with desirable traits to enhance crop productivity.

Agriculture in arid and semiarid regions encounters substantial challenges attributable to climatic variability, limited water resources, and nutrient-deficient soils. Nitrogen (N) is essential for tomato (Solanum lycopersicum) growth and affects yield, water efficiency, and fruit quality. Agri-photovoltaic (Agri-PV) systems offer a promising and sustainable solution to land-use competition by concurrently facilitating solar energy generation and horticultural production. This study examined the combined effects of nitrogen application rate and Agri-PV-induced shading on the physiological performance and yield characteristics of tomatoes. The experiments were carried out with tomato seeds planted in an Agrovoltaics experimental field at the School of Agriculture, University of Namibia, Namibia. The split–split plot experimental design featured two nitrogen levels: the recommended rate (150 kg N ha⁻¹) and an adaptive rate (120 kg N ha⁻¹), combined with three shading conditions: 60% shade (chequered boards), 40% shade (opaque boards), and full sunlight (control). Phosphorus (P) and potassium (K) were applied at the recommended rates of 90 kg P ha⁻¹ and 75 kg K ha⁻¹. Growth and yield parameters were analysed using SAS 9.4. There were no statistically significant differences in yield between the nitrogen levels; however, shading treatments significantly influenced fruit weight yield, with intermediate shading enhancing production. At harvest, the 40% chequered shade treatment showed the highest values of fresh fruit yield (kg/m²) compared to opaque and with similar values of fruit numbers. These outcomes indicate that Agri-PV systems can control microclimatic conditions, reducing excessive heat and light stress while sustaining or enhancing crop productivity. The integration of Agri-PV with optimised nitrogen management supports both renewable energy generation and sustainable agriculture, offering a viable strategy for climate-smart food production systems.

Striga hermonthica infestation and recurrent drought are major constraints to sorghum production in sub-Saharan Africa, significantly reducing both grain yield and nutritional quality. Developing sorghum varieties that combine resistance to Striga with enhanced nutritional traits is therefore a priority for food security and sustainable agriculture. This study investigated the genetic basis of Striga resistance and nutritional composition in 75 diverse sorghum genotypes, including advanced breeding lines and released varieties from Zimbabwe and South Africa. Whole-genome sequencing of genomic DNA from these genotypes was performed to identify single-nucleotide polymorphisms (SNPs) associated with secondary metabolites and macronutrient traits. SNPs linked to the biosynthesis of key phenolic acids—including hydroxybenzoic, gallic, ferulic, cinnamic, p-coumaric, caffeic, protocatechuic, and syringic acids—were distributed across multiple chromosomes, with chromosome 1 exhibiting the highest density of associated SNPs. Manhattan plot analyses highlighted significant associations for caffeic acid on chromosomes 1 and 9, protocatechuic acid on chromosomes 2, 3, 4, 5, and 10, and syringic acid on chromosomes 3, 5, 8, 9, and 10. Similarly, SNPs associated with macronutrient composition—including ash, carbohydrate, fat, fibre, and protein—were identified on chromosomes 1, 3, 4, 8, and 9. Several genomic regions were found to potentially exert pleiotropic effects, influencing both Striga resistance and nutritional traits, indicating co-localized genetic control. These findings provide a detailed map of key genomic regions underlying resilience and dietary quality in sorghum. The identified SNP markers can serve as valuable tools for marker-assisted selection, enabling the development of sorghum varieties that are both Striga-tolerant and nutritionally enhanced. By integrating resistance and nutritional profiling at the genomic level, this study contributes to the advancement of sorghum breeding strategies aimed at improving food security and nutritional outcomes in stress-prone environments of sub-Saharan Africa.

Rice sheath blight (RSB), caused by the soil-borne necrotrophic fungus Rhizoctonia solani, is a major disease that can lead to significant yield losses under favorable conditions. Resistance to RSB is a complex quantitative trait controlled by multiple genes, but no single dominant resistance gene or locus has been identified to date. This study used a Genome-Wide Association Study (GWAS) to identify genetic loci associated with RSB resistance in a panel of 200 diverse rice varieties, including traditional upland and lowland varieties originating from Malaysia. We employed a double-digest RAD sequencing (ddRAD) approach to genotype the population. Bioinformatic analysis of sequencing data from 197 samples revealed two major genetic clusters and an optimal population structure (K=3). Phenotypic screening for sheath blight resistance showed that both lesion length (PL) and relative lesion height (PJ) data were normally distributed, making them suitable for parametric statistical analysis. The GWAS successfully identified a significant locus on Chromosome 5 associated with RSB resistance. A total of four significant SNPs were annotated to the gene LOC_Os05g47770, which encodes a Serine/Threonine-Protein Kinase (STPK). This gene family is widely recognized for its role in plant defense responses. This discovery provides crucial genetic insights for developing DNA markers for marker-assisted selection (MAS) in rice breeding programs, ultimately contributing to the creation of more disease-resistant rice varieties.

Indian agriculture has long depended on chemical fertilizers to sustain food production; however, their continuous, indiscriminate and imbalanced use has caused nutrient depletion, organic carbon loss, and decline in soil microbial activity, jeopardizing long-term productivity. To counter these challenges, integrated nutrient management approaches that combine inorganic fertilizers with organic and biological inputs are gaining importance. Microbial-enriched manures and nano-emulsion biofertilizers, in particular, are promising options for enhancing nutrient availability, stimulating crop growth, and restoring soil health while reducing dependence on synthetic fertilizers. A field study was conducted during the winter (Rabi) season of 2023–24 at Coimbatore, Tamil Nadu, India, to evaluate the effects of microbial-enriched organic manures and nano-emulsion biofertilizers on soil fertility, microbial dynamics, and chickpea (Cicer arietinum L.) productivity under irrigated conditions. The experiment, laid out in a randomized block design with twelve treatments, combined varying levels of recommended fertilizer dose (RDF) with farmyard manure, vermicompost, microbial-enriched amendments, and nano-emulsion formulations. Results revealed that application of 100% RDF + microbial-enriched vermicompost (6 t ha⁻¹) significantly improved plant growth, dry matter accumulation, physiological indices, nutrient uptake, and microbial activity, producing a higher grain (1276 kg ha⁻¹) and stover yield (2569 kg ha⁻¹). Soil analysis confirmed improvements in organic carbon, available nutrients, microbial biomass, and enzymatic activities under this treatment. Economic evaluation showed that, while this combination achieved maximum gross returns (INR 95,700 ha⁻¹), the treatment with 75% RDF + nano-emulsion biofertilizer delivered superior net returns (INR 56,785 ha⁻¹) and benefit–cost ratio (2.72). The integration of microbial-enriched vermicompost with recommended dose of fertilizers (RDF) significantly improves chickpea yield and soil health, while partial replacement of RDF with nano-emulsion biofertilizers presents a viable, economical, and eco-friendly alternative.

Extracellular polymeric substances (EPSs) are biopolymers that can be recovered from waste aerobic granular sludge (AGS) generated in wastewater treatment plants (WWTPs). These biopolymers represent a valuable resource with attractive attributes, making them suitable for applications across different sectors. In agriculture, EPSs have attracted growing interest, although their beneficial effects are still underexplored. In a 7-week greenhouse experiment, the effects of EPSs recovered from waste AGS sourced from two WWTPs (Utrecht (EPS_U) and Faro (EPS_F)) and a lab-scale reactor (EPS_R) on maize growth, photosynthetic efficiency, and nutrient uptake and use efficiency were explored. EPSs were incorporated into the soil at doses of 0.5% and 1% (w/w), and their effects were evaluated against equivalent doses of vermicompost and non-amended soil (control). EPS incorporation, especially with 1% EPS_R, enhanced stem thickness and shoot fresh weight, whereas lower doses of other EPS sources and vermicompost had only marginal effects. Additionally, EPSs, regardless of their source, markedly enhanced the chlorophyll content compared to plants grown in non-amended soils, demonstrating their role in enhancing nutrient availability and maize photosynthetic efficiency. Moreover, the incorporation of EPS_R_1% and EPS_F_1% markedly increased the Mg and K uptake by 46% and 34%, respectively, compared to the control. Some EPS treatments were also able to increase the use efficiency of Ca, K, Na, and Zn, compared to plants in vermicompost-treated soils. As such, EPSs can effectively enhance the availability, uptake, and use of nutrients in maize.

The study highlights the potential of waste-derived biopolymers to enhance maize nutritional traits and physiological responses while promoting sustainable agricultural practices and resource recovery strategies.

Acknowledgments: This work was financed by the project ReCROP (PRIMA/0002/2020) funded by FCT. The authors thank the CBQF scientific collaboration under the FCT project UIDB/50016/2020. Catarina Miranda thanks the research grant from FCT (doi.org/10.54499/2020.06577.BD).

Intensive agricultural practices contribute to soil erosion, compaction, and the depletion of soil organic carbon and essential nutrients. There is a growing demand for sustainable practices that enable efficient crop production while minimizing environmental impact. Among these, multi-cropping has emerged as a promising strategy to address major agroecosystem challenges such as biodiversity loss, declining soil fertility, and increased greenhouse gas emissions. Prior studies have shown that crop interactions and interspecific competition in multi-cropping systems enhance root development and improve soil structural stability. Balandaitė et al. (2024) noted that multi-cropping is becoming a promising technique in agriculture.

A stationary field experiment was established in 2024 at the Experimental Station of Vytautas Magnus University Agriculture Academy (Lithuania; 54°53′N, 23°50′E), on Endocalcaric Amphistagnic Luvisol. The study aims to evaluate the effects of multi-cropping and nutrient relay on soil physical properties, crop development, and environmental indicators across two full crop rotation cycles.

Soil aggregate structure, stability, electrical conductivity, and greenhouse gas emissions were assessed before sowing and after harvest. Biomass samples were collected following the final cut. Preliminary results indicate that aggregate stability in multi-cropping systems is higher compared to monoculture spring barley, with a greater proportion of macroaggregates observed. These findings align with previous research showing that post-harvest residues from systems combining barley and red clover provide higher nutrient retention than monocultures. Additional results on biomass nutrient content are forthcoming.

In conclusion, multi-cropping positively influenced soil structure and stability in both the first and second crop rotations. The impact of nutrient relay will be further evaluated through subsequent assessments of the diagnostic crop. Ongoing observations across the full rotation cycles aim to provide insights supporting regenerative agriculture and alignment with the EU Green Deal objectives.

Water scarcity is one of the major constraints in agriculture, particularly affecting crop growth and development in arid and semiarid regions. As climate change intensifies the frequency and severity of drought events, there is a growing need for sustainable strategies to enhance crop resilience under limited water availability. Organic amendments such as compost have gained attention for their potential to improve soil health, water retention, and plant stress tolerance. In this line, this study evaluates, in a pot experiment under controlled conditions, the impact of garden waste compost application on tomato (Solanum lycopersicum) growth under varying levels of water deficit (100%, 60%, and 40% of field capacity, FC) in order to simulate optimal, moderate, and severe water stress conditions, respectively. The application of compost significantly enhanced plant growth and biomass accumulation across all the irrigation levels, with the most pronounced benefits observed under moderate water deficit (60% FC). These results suggest that compost amendments can improve plant performance and mitigate the adverse effects of water stress deficit, emphasizing their potential role in promoting water scarcity resilience in sustainable agriculture.

Acknowledgements: This work was supported by the INTERREG-POCTEP Spain-Portugal programme and the European Regional Development Fund through the project FRONTEIRA HUELLA ZERO_2030: POR UNA FRONTERA SUSTENTÁVEL.