Sustainable Agriculture In Arid Regions Research Articles

Antibiotics Resistance and PGPR Traits of Endophytic Bacteria Isolated in Arid Region of Morocco

This study aimed to characterize endophytic bacteria isolated from legume nodules and roots in the rhizosphere soils of Acacia trees in Morocco’s arid regions. The focus was on identifying bacterial strains with plant growth-promoting rhizobacteria (PGPR) traits and antibiotic resistance, which could enhance legume productivity under various abiotic stresses. Autochthonous legumes were used to harbor the endophytic bacteria, including chickpea (Cicer arietinum), faba bean (Vicia faba), lentil (Lens culinaris), and common bean (Phaseolus vulgaris). In a previous study, seventy-two isolates were obtained, and molecular characterization grouped them into twenty-two bacterial isolates. These twenty-two bacterial isolates were then further analyzed for their antibiotic resistance and key PGPR traits, such as phosphate solubilization, indole-3-acetic acid (IAA) production, and siderophore production. The results revealed that 86.36% of the isolates were resistant to erythromycin, 45.45% to ciprofloxacin, 22.73% to ampicillin-sulbactam, and 9.09% to tetracycline, with ciprofloxacin and tetracycline being the most effective. All isolates produced IAA, with HN51 and PN105 exhibiting the highest production at 6 µg of IAA per mg of protein. The other isolates showed varying levels of IAA production, ranging from moderate to low. Siderophore production, assessed using CAS medium, indicated that the strains PN121, LR142, LNR146, and HR26 exhibited high production, while the rest demonstrated moderate to low capacities. Additionally, 18.2% of the isolates demonstrated phosphate solubilization on YED-P medium, with PR135 and LNR135 being the most efficient, achieving solubilization indices of 2.14 and 2.13 cm, respectively. LR142 and LNR146 showed a moderate solubilization efficiency. Overall, these findings indicate that these isolated endophytic bacteria possess significant potential as biofertilizers, owing to their antibiotic resistance, IAA production, siderophore production, and phosphate solubilization abilities. These characteristics position them as promising candidates for enhancing legume growth under abiotic stress and contributing to sustainable agriculture in arid regions.

An Affordable System Solution for Enhancing Tree Survival in Dry Environments

Water scarcity inhibits plant growth, especially in arid regions. Traditional irrigation methods often lack efficiency and sustainability. This study investigates AquaTrap, a biomimetic design, as a potential solution. The study highlights AquaTrap’s advantages by analyzing its design and previous research on bioinspired water harvesting. It highlights its ability to increase water efficiency and support sustainable plant growth in dry areas. Biomimicry inspires AquaTrap’s design, which mimics natural systems to capture and deliver water to plant roots. To collect condensation while repelling water, the stack uses superhydrophobic materials. Plant roots then receive this accumulated water for growth. Compared to traditional methods, AquaTrap offers many advantages. Its stand-alone design eliminates complex infrastructure and minimizes evaporation. Additionally, delivering water directly to the roots reduces waste and increases water efficiency. This technology holds promise for introducing new vegetation, restoring plant life, and promoting sustainable agriculture in arid regions. Further research is needed to explore the potential of AquaTrap in a variety of field conditions, optimize it for different plants and environments, and evaluate its economic feasibility for widespread use. AquaTrap also has significant potential for sustainable forestry, as it can significantly increase the survival and growth of trees in water-scarce environments. System solution opportunities and modular structure provide crucial support during the most critical adaptation period of afforestation. By reducing water consumption and increasing efficiency, it supports the establishment and maintenance of healthy forests, which are vital for ecosystem resilience and biodiversity.

Enhancing Irrigated Land Use Efficiency in Southern Kazakhstan's Agricultural Sectors

This study aims to improve the efficiency of irrigated land use in the agricultural sectors of southern Kazakhstan. This region is known for its significant contribution to the nation's agricultural output. Recognizing the challenges posed by suboptimal water management practices and the increasing effects of climate change, this research takes a multidisciplinary approach to propose sustainable agricultural practices. We conducted an empirical analysis over a three-year period, comparing current irrigation techniques with the implementation of innovative water-saving technologies. The study also evaluates the socio-economic impacts of improved irrigation practices on local farming communities. Preliminary results indicate that the use of precision irrigation systems can greatly reduce water wastage and increase crop yields. Additionally, the research highlights the crucial role of farmer education and cooperative management structures in achieving sustainable water use. By combining technological advancements with community-based management, this study provides a scalable model for optimizing irrigated land use that could be replicated throughout Central Asia. The findings aim to contribute to policy discussions on sustainable agriculture in arid regions, emphasizing the importance of tailored solutions that address both environmental and socio-economic factors.

Роль биомелиорантов в снижении электропроводности и засоленности почв

This study aimed to evaluate the impact of biomeliorants on soil electrical conductivity and salinity under the arid conditions of the Syrian Arab Republic. Field experiments were conducted using compost, biopreparations based on Bacillus bacteria, and their combination. Electrical conductivity was measured at four depths: 0-25 cm, 26-50 cm, 51-75 cm and 76-100 cm. The methodology included the use of graphite electrode cells and a conductometer calibrated with standard potassium chloride (KCl) solutions. Soil samples were collected from various depths, dried at 105°C, sieved through a 2 mm sieve, mixed with distilled water in a 1:2 ratio, stirred, and left for 24 hours. Three measurements of electrical conductivity were then taken for each sample. The results showed a significant reduction in soil electrical conductivity with the application of biomeliоrants particularly at the 0-25 cm depth. Two-factor ANOVA and Tukey’s test confirmed statistically significant differences between the experimental treatments. The combination of compost and biopreparations demonstrated the greatest effectiveness in reducing electrical conductivity. These findings indicate the high efficiency of biomeliorants in improving soil conditions and reducing salinity, which is crucial for sustainable agriculture in arid regions. The introduction of biomeliorants helped reduce the content of soluble salts and improve soil structure, ultimately leading to increased crop yields.

Plant growth promotion of barley with Azospirillum brasilense and Bacillus subtilis to achieve sustainable agriculture in arid regions

Plant growth promotion of barley with Azospirillum brasilense and Bacillus subtilis to achieve sustainable agriculture in arid regions

Evaluation of the Mycorrhizal Potential of Date Palm (Phoenix dactylifera L.) Rhizosphere Soils in the Figuig Oasis (Southeastern Morocco).

Date palm, an important crop in Morocco and many other arid regions around the world, faces significant challenges from wind, water shortages, and salinization, which contribute to vegetation loss and soil degradation in the harsh environmental conditions of oasis ecosystems with low soil fertility. Protecting and regenerating these degraded lands is crucial for sustainable agriculture and improving the dryland ecosystem. Arbuscular mycorrhizal fungi (AMF) comprise a vital element in this dynamic within the microflora of the soil rhizosphere. This study evaluated the potential in mycorrhizal soil and identified AMF in date palm rhizospheres in eight locations within the Figuig oasis (southeastern Morocco). This study found that Extension and Zenaga had more mycorrhizal propagules than other locations. Replanted maize (Zea mays L.) in these soils exhibited higher mycorrhization rates (91-93%) compared to that in other locations, with the Lamaiz site registering the lowest rate (39%). The phosphorus content was negatively correlated with the AMF spore frequency, intensity, and density, while a positive correlation was detected between the soil pH and the AMF spore frequency and density. The morphological identification of spores revealed Glomus as the predominant species, along with Acaulospora and Sclerocystis. This study represents an initial step toward the potential application of these fungi in environmental conservation and sustainable agriculture in arid regions.

Plant growth-promoting properties of endophytic bacteria isolated from some xerophytic plants distributed in arid regions (Uzbekistan)

Recent advancements in the development of endophytic microorganisms-based stimulants have shown promising potential in various fields. Research on the identification of these endophytic microorganisms has been well reported, however, there are limited studies of these endophytes isolated from plants in arid regions. Thus, isolation and identification of promising microbial endophytes from xerophytic plants is essential in technology development for sustainable agriculture in arid regions. This study aims to identify the endophytic bacteria isolated from Kochia prostrata (L.) Schrad. and Ceratoides eversmanniana (Stschegl. ex I.G.Borshch.) Botsch. & Ikonn. in vertical zones of arid regions of Uzbekistan, and examine their potential plant growth-promoting properties. Using Luria-Bertani (LB) medium, 70 distinct bacterial colony were isolated from the different segments of K. prostrata and C. eversmanniana. These isotypes were screened using NaCl-supplemented LB medium in which nine promising bacterial isolates showed tolerance to 15% NaCl. The nine promising halophytes were subjected to molecular identification using specific primers. The isolates from K. prostrata are identified as Bacillus amyloliquefaciens, Bacillus pumilus, Priestia aryabhattai, Pseudomonas putida, and Priestia endophytica. On the other hand, Priestia megaterium, Pseudomonas putida, Bacillus subtilis and Brevibacillus parabrevis were isolated from C. eversmanniana. The identified isolates also showed significant plant growth-promoting properties (N2-fixation, IAA production, phosphates solubilization, ACC deaminase production, siderophores production) and shows ability to inhibit pathogenic fungal growth. Based on the result, the identified bacterial endophytes can be processed as growth-stimulants and biological control of fungal pathogens in crops in arid regions.

Influence of environmental-friendly bio-organic ameliorants on abiotic stress to sustainable agriculture in arid regions: A long term greenhouse study in northwestern Egypt

The problem of soil salinity is rapidly increasing, with more than 950 million hectares affected by salinity stress (Arora et al., 2017). The amelioration of saline-sodic soils using chemical ameliorates could increase CO2 emissions and soil degradation. Therefore, amending saline-sodic soil with environmentally friendly bio-organic ameliorants such as brewer's spent grain (SG) and Azospirillum (A. brasilense) bacteria could represent a safe and cheaper approach compared to other organic (compost; CT) and mineral fertilizers. Under greenhouse conditions, maize was grown in saline-sodic soil amended with bio-organic ameliorants. Nine treatments were included; (i) SG1 (23.8 t ha−1); (ii) SG2 (47.6 t ha−1); (iii) TC1 (23.8 t ha−1); (iv) TC2 (47.6 t ha−1); (v) injection of A. brasilense with corn seeds (Az); (vi) combination of A. brasilense and SG (Az + SG1); (vii) combination of A. brasilense and compost (Az + TC1); (viii) mineral fertilizers (NPK) and (ix) the control (CK). The results revealed that soil amended with Az and SG2 significantly decreased the exchangeable sodium percentage (ESP) and higher cation exchange capacity (CEC). Compared with the control, the exchangeable sodium (Ex-Na+) concentration was decreased by 53.2 and 49.27%, for Az and Az + SG1 treatments, respectively. The fresh- and dry weight observed for Az + SG1, SG2, and Az treatments were increased compared to TC1, TC2, NPK, and CK treatments. The grain and biological yields were higher in Az + SG1 and SG2 than in TC2, NPK ameliorants, and CK. The bio-organic ameliorants alleviated the abiotic stress, enhance the growth and productivity of corn plants, decrease soil ESP and Na+ content, and enhance soil fertility. In conclusion, the application of SG2 can enhance the growth, and productivity of maize grown under salinity-sodicity stress. Therefore, SG2 and Az + SG1 are recommended for direct application in saline-sodic soil.

Salt\u2011responsive transcriptome analysis of canola roots reveals candidate genes involved in the key metabolic pathway in response to salt stress

Salinity is a major constraint on crop growth and productivity, limiting sustainable agriculture in arid regions. Understanding the molecular mechanisms of salt-stress adaptation in canola is important to improve salt tolerance and promote its cultivation in saline lands. In this study, roots of control (no salt) and 200 mM NaCl-stressed canola seedlings were collected for RNA-Seq analysis and qRT-PCR validation. A total of 5385, 4268, and 7105 DEGs at the three time points of salt treatment compared to the control were identified, respectively. Several DEGs enriched in plant signal transduction pathways were highly expressed under salt stress, and these genes play an important role in signaling and scavenging of ROS in response to salt stress. Transcript expression in canola roots differed at different stages of salt stress, with the early-stages (2 h) of salt stress mainly related to oxidative stress response and sugar metabolism, while the late-stages (72 h) of salt stress mainly related to transmembrane movement, amino acid metabolism, glycerol metabolism and structural components of the cell wall. Several families of TFs that may be associated with salt tolerance were identified, including ERF, MYB, NAC, WRKY, and bHLH. These results provide a basis for further studies on the regulatory mechanisms of salt stress adaptation in canola.

Evaluation of Subsurface Drip Irrigation Designs in a Soil Profile with a Capillary Barrier

Enhanced water use efficiency (WUE) is the key to sustainable agriculture in arid regions. The installation of capillary barriers (CB) has been suggested as one of the potential solutions. CB effects are observed between two soil layers with distinctly different soil hydraulic properties. A CB helps retain water in the upper, relatively fine-textured soil layer, suppressing water losses by deep drainage. However, retaining water in a shallow surface layer also intensifies water loss by evaporation. The use of subsurface drip irrigation (SDI) with a CB may prevent such water loss. This study evaluated the performance of SDI in a soil profile with a CB using a pot experiment and numerical analysis with the HYDRUS (2D/3D) software package. The ring-shaped emitter was selected for the SDI system for its low capital expenditures (CapEx) and maintenance. Strawberry was selected as a model plant. The results indicated that the proposed SDI system with a CB was effective in terms of WUE. The numerical analysis revealed that the CB’s depth influences the system’s water balance more than the ring-shaped emitter’s installation depth. While the CB’s shallow installation led to more root water uptake by the strawberry and less water loss by deep drainage, it induced more water loss by evaporation.

The Integration of Multivariate Statistical Approaches, Hyperspectral Reflectance, and Data-Driven Modeling for Assessing the Quality and Suitability of Groundwater for Irrigation

Sustainable agriculture in arid regions necessitates that the quality of groundwater be carefully monitored; otherwise, low-quality irrigation water may cause soil degradation and negatively impact crop productivity. This study aimed to evaluate the quality of groundwater samples collected from the wells in the quaternary aquifer, which are located in the Western Desert (WD) and the Central Nile Delta (CND), by integrating a multivariate analysis, proximal remote sensing data, and data-driven modeling (adaptive neuro-fuzzy inference system (ANFIS) and support vector machine regression (SVMR)). Data on the physiochemical parameters were subjected to multivariate analysis to ease the interpretation of groundwater quality. Then, six irrigation water quality indices (IWQIs) were calculated, and the original spectral reflectance (OSR) of groundwater samples were collected in the 302–1148 nm range, with the optimal spectral wavelength intervals corresponding to each of the six IWQIs determined through correlation coefficients (r). Finally, the performance of both the ANFIS and SVMR models for evaluating the IWQIs was investigated based on effective spectral reflectance bands. From the multivariate analysis, it was concluded that the combination of factor analysis and principal component analysis was found to be advantageous to examining and interpreting the behavior of groundwater quality in both regions, as well as predicting the variables that may impact groundwater quality by illuminating the relationship between physiochemical parameters and the factors or components of both analyses. The analysis of the six IWQIs revealed that the majority of groundwater samples from the CND were highly suitable for irrigation purposes, whereas most of the groundwater from the WD can be used with some limitations to avoid salinity and alkalinity issues in the long term. The high r values between the six IWQIs and OSR were located at wavelength intervals of 302–318, 358–900, and 1074–1148 nm, and the peak value of r for these was relatively flat. Finally, the ANFIS and SVMR both obtained satisfactory degrees of model accuracy for evaluating the IWQIs, but the ANFIS model (R2 = 0.74–1.0) was superior to the SVMR (R2 = 0.01–0.88) in both the training and testing series. Finally, the multivariate analysis was able to easily interpret groundwater quality and ground-based remote sensing on the basis of spectral reflectance bands via the ANFIS model, which could be used as a fast and low-cost onsite tool to estimate the IWQIs of groundwater.

Optimizing Cropping Systems of Cultivated Pastures in the Mountain–Basin Systems in Northwest China

Cultivated pastures are effective supporting systems of natural grassland preservation and sustainable agriculture in arid regions of northwest China. The adaptive combination of forage species enhances the yields and ecological functions of cultivated pastures. Legume–grass intercropping is a valuable sowing regime because of the niche differentiation and resource acquisition. Understanding the effects of species interactions in legume–grass intercropping systems can provide scientific and practical guidance on cultivated pasture management. In this study, we conducted a field experiment to determine the advantages and effects of alfalfa (Medicago sativa L.) annual grass intercropping on cultivated pastures. We analyzed the data on population traits, community characteristics and dry matter in the growing period to evaluate the effects of variety and sowing patterns with the following treatments: three alfalfa varieties (Algonquin, Leafy king, WL354HQ) sown in monocultures and mixed with oat (Avena sativa L.) or sudangrass (Sorghum sudanense (Piper) Stapf.) with two seeding ratios. Our results suggest that in mixtures, the plant traits of alfalfa were determined by their own characters at the earlier stage but were affected more by companion grass at the later stage. The annual forage grass companion impaired the growth of alfalfa during the growth period. In mixtures, sudangrass displayed a stronger inhibiting effect on alfalfa than oat. Alfalfa–grass intercropping was proved to be a feasible cropping practice in terms of yield, production stability and weed control, due to their complementary use of resources in comparison with alfalfa monocropping. Alfalfa–annual grass intercropping is a beneficial alternative strategy to obtain effective cultivated pastures in arid regions.

Assessment of Reclamation Treatments of Abandoned Farmland in an Arid Region of China

Reclamation of abandoned farmland is crucial to a sustainable agriculture in arid regions. This study aims to evaluate the impact of different reclamation treatments on abandoned salinized farmland. We investigated four artificial reclamation treatments, continuous cotton (CC), continuous alfalfa (CA), tree-wheat intercropping (TW) and trees (TS), which were conducted in 2011–2012 in the Manasi River Basin of Xinjiang Province, China. Soil nutrient, microorganism and enzyme activity were examined in comparison with natural succession (CK) in an integrated analysis on soil fertility improvement and soil salinization control with these reclamations. Results indicate that the four artificial reclamation treatments are more effective approaches than natural restoration to reclaim abandoned farmland. TW and CA significantly increased soil nutrient content compared to CK. CC reduced soil salinity to the lowest level among all treatments. TW significantly enhanced soil enzyme activity. All four artificial reclamations increased soil microbial populations and soil microbial biomass carbon. TW and CA had the greatest overall optimal effects among the four treatments in terms of the ecological outcomes. If both economic benefits and ecological effects are considered, TW would be the best reclamation mode. The findings from this study will assist in selecting a feasible method for reclamation of abandoned farmland for sustainable agriculture in arid regions.

Effects of irrigation on accumulation and distribution of dry matter and grain yield in winter wheat in arid regions of China

Aims Our objective was to determine the effects of irrigation schedule on grain yield, water use efficiency(WUE), and accumulation and distribution of dry matter in winter wheat(Triticum aestivum) ‘Lingkang-2’ in the arid Hexi corridor of Northwest China. Methods Based on pre-winter irrigation quota of 180 mm, we set up five irrigation treatments, i.e., irrigation quota of 165 mm at the jointing stage(W1), irrigation quota of 120 mm at the jointing stage and 105 mm at the heading stage(W2), irrigation quota of 105 mm at the jointing, heading and grain filling stages, respectively(W3), irrigation quota of 75 mm at the jointing, heading and grain filling stages, respectively(W4), and irrigation quota of 105 mm at the jointing stage, 75 mm at the heading stage, and 45 mm at the grain filling stage(W5). Important findings Available soil water content(AWC) in the 0–150 cm layer across different irrigation treatments changed with wheat growth stages. The grain yield in both W3 and W4 treatments was obviously improved by higher leaf area index(LAI) and dry matter accumulation. Higher AWC was found in the W3 and W4 treatments, but there was no significant difference in the grain yield between the two treatments. Nevertheless, the highest water use efficiency(WUE) in the W4 treatment was associated with its higher value of growth index than those in the W1, W2 and W5 treatments. In contrast, LAI in the W1, W2 and W5 treatments quickly decreased after anthesis, corresponding to lower dry matter accumulation, shorter grain filling duration and fewer numbers of spike and lower 1000-grain weight. We also observed that drought stress after anthesis promoted dry matter translocation from vegetative organs to grains, with a complementary effect on grain yield occurring as drought stress increased. In the grain filling stage, drought stress stimulated average filling rate, but shortened the durationof grain filling. The duration of grain filling, effective period of grain filling, the value of increases in grain weight during effective period of grain filling, and the timing of the maximum filling rate were positively correlated with 1000-grain weight and grain yield of winter wheat(p < 0.05). In consideration of all results, winter wheat should be irrigated at 75 mm at the jointing, heading and filling stages to achieve reasonable water use efficiency and grain yield. Our findings may help with the decision makers by providing hydrological and ecological evidence in development of sustainable agriculture in arid regions.

Permanent raised beds improved soil structure and yield of spring wheat in arid north‐western China

AbstractIn arid north‐western China, soil degradation, limited water and subsequent yield decline, largely as a result of excessive tillage and residue removal practices, are the main factors limiting further development of local agriculture. The effects of permanent raised beds (PRB), no‐till (NT) and traditional tillage (TT) on soil structure and yield were investigated in a wheat (Triticum aestivum L.) – maize (Zea mays L.) cropping system from 2004 to 2009 in the Hexi Corridor of Gansu Province, China. PRB and NT had more macro‐aggregates (&gt;0.25 mm, +2.7%), a better distribution of pore size classes and improved hydraulic conductivity, whereas TT soils were dominated by micro‐aggregates and micro‐porosity. In PRB, soil bulk density decreased significantly by 6.3 and 7.0% for the 0‐ to 10‐cm and 20‐ to 30‐cm depths relative to TT. The PRB mean crop yields increased by 4.2% and water use efficiency improved by 21.3% compared with TT because of greater soil moisture and improved soil physical and chemical status. These improvements in soil properties, yield and water use are of considerable importance for soil regeneration, food security and sustainable agriculture in arid regions, such as north‐western China.