Ahmed Abd El-Aziz Mahmoud Awad

Background: Among abiotic stresses, salinity and socidity are the major productivity-limiting factors for cultivated crop plants. In two seasons (2022 and 2023), two field-level experimental attempts were made to study the impacts of urea–phosphate (UP) and magnesium oxide nanoparticles (MgNPs) and their combination on the nutritional status, physiological attributes, and yields of Glycine max (L) plants growing under saline-sodic conditions. At 30, 45, and 60 days, UP was applied to the soil at rates of 85.0, 107.0, 127.0, and 150.0 kg ha ^-1 , corresponding to UP ₁ , UP ₂ , UP ₃ , and UP ₄ , respectively, as well as MgONPs via foliar application at doses of 0.0, 50.0, and 100.0 mg L ^-1 , corresponding to MgONP ₀ , MgONP ₁ , and MgONP ₂ , respectively. This study was conducted in a split-plot structure according to a randomized compete block design with three replicates. Results: Our results showed that UP ₃ and UP ₄ had the strongest effects on most of the measured traits. Both application rates produced the maximum growth–physiological attribute values, except for the leaf dry matter percentage and leaf nutrient levels in both seasons and the leaf iron and zinc contents in the first season (the highest values in these characteristics were achieved in the untreated plants). In addition, the UP ₄ -fertilized plants produced the highest 100-seed weight (HSW), total seed yield (TSY), and seed manganese contents in the two growing seasons. The highest seed oil contents in both seasons, as well as the highest seed phosphorus, calcium, and copper contents in 2023, were recorded in the UP ₃ -treated plants. Regarding MgONPs, our results revealed the significant superiority of the MgONP-treated plants in terms of all the aforementioned growth–physiological parameters and leaf macro- and micronutrient contents, irrespective of the applied dose, except for the LMnCs in 2022 and 2023. The integrative application revealed the clearly superior influence of applying UP ₃ or UP ₄ with MgONP ₂ and MgONP ₃ on most studied traits. Specifically, for TSY, Model 3 in the 2022 season (adjusted R ² ₂ = 0.931) and Model 2 in LPC, LA, and LCaC as the most influential attributes in 2022, and LNC and LKC in 2023. For seed oil content (SOC), Model 3 in 2022 (adjusted R ² ₂ = 0.344) and Model 2 in 2023 (adjusted R ² ₂ = 0.278) were selected, with SPAD readings and LMnC in 2022, and LMnC and HSW in 2023 as key predictors. Conclusions: The use of high rates of a highly soluble and acidic-impact fertilizer, such as UP supplemented with magnesium oxide nanoparticles, may be recommended in saline environments.

A combination of abiotic stresses, such as salinity and calcification, can be even more destructive to crop performance than the effects of each type of stress alone. Two field experiments (in 2022 and 2023) attempted to explore the individual impact of three nitrogenous fertilizer types (NFTs, including ammonium nitrate, urea, and ammonium sulfate: N₁, N₂, and N₃, respectively) and three other phosphate fertilizer types (PFTs, including calcium super-phosphate, mono-ammonium phosphate, and urea phosphate: P₁, P₂, and P₃, respectively) and their interactive effects on nutritional status, physiological growth attributes, yield, and the quality attributes of sweet potato (Beauregard cv.) plants cultivated in saline–calcareous soil. This study was carried out using a split-plot system in a randomized complete block design with three replications. The results obtained for both seasons indicated that ammonium sulfate was the superior fertilizer in terms of its effects on leaf macronutrient contents, except for those of nitrogen and magnesium, which were the most impacted when ammonium nitrate and urea were used, respectively. In addition, plants fertilized with N₁ demonstrated the highest ion homeostasis values, plant height, and calcium and magnesium contents in tuberous roots. Likewise, applying P₃ was the most impactful on leaf macro- and micronutrient content, except for that of calcium, as well as magnesium and copper, which were the most affected when P₁ and P₂ were used, respectively. The use of P₃ also produced the best results in terms of SPAD readings, leaf area, tuberous root volume, diameter, and total root yield. Furthermore, after applying P₁, we recorded the highest ion homeostasis values, tuberous potassium, and calcium content. The coupled application of N₁ and N₃ with both P₂ and P₃ was the most effective in most of the characteristics we studied.

The main objective of this research was to determine the land productivity index based on a parametric approach using geographic information systems (GIS( and Remote sensing (RS). This study was conducted in the Nubian Nasr Area, located between 24° 27' 30"N and 24° 35' 0"N latitude, and 33° 0' 0"E and 33° 6' 0"E longitude, in Aswan Governorate, Egypt. The study area covers about 107.51Km^2 (10750.64 hectare). To achieve this objective, 27 soil profiles were chosen to cover the study area, and 81 soil samples were collected. Soil samples were analyzed for their parameters using the standard methods of soil analysis. Accordingly, land productivity was calculated for all studied soil profiles, and a result map was generated for the land productivity index utilizing GIS. According to the results, it was found that most of the land productivity for field crops, forage crops, and fruit trees was concentrated in the Average (III) class with rates of 51.85% (5574.21 hectares), 48.15% (5176.43 hectares), and 37.04% (3982.04 hectares), respectively. The second class, good (II) for agricultural use, came in second place with the following order: 25.93% (2787.64 hectares), 22.22% (2388.79 hectares), and 33.34% (3584.26 hectares) for field crops, forage, and fruit trees, respectively. The poor class (IV) represented 18.52% (1991.02 hectares) of field crops, 29.63% (3185.41 hectares) for forage crops, and 25.93% (2786.56 hectares) for fruit trees. The excellent class (I) represented about 3.71% (397.77 hectares) for both field crops and fruit trees, while it was nil for forage crops.

Purpose: Based on its crucial regulatory role in several biochemical processes, potassium (K) is considered to greatly influence fruit yield and quality. Methods: Two field experiments were carried out in two seasons (2021 and 2022) to explore the response of lemon (Baladi cv.) trees grown in K-deficient soil to four different K fertilizer sources applied individually as a foliar spray. K citrate (KC₁ = 1.3 vs. KC₂ = 2.6 g L^− 1), K nitrate (KN₁ = 1.5 vs. KN₂ = 3.0 g L^− 1), K tartrate (KT₁ = 1.5 vs. KT₂ = 3.0 g L^− 1), and K thiosulfate (KS₁ = 1.25 vs. KS₂ = 2.5 g L^− 1) were applied three times, and the treated trees were compared with untreated trees. This study was established with a randomized complete block design (RCBD) using four replicates. Results: The findings revealed that the KC treatment, regardless of dosage, showed clear superiority in terms of the values for the leaf phosphorus (%), manganese, and zinc contents (mg kg^− 1), as well as fruit firmness, fruit dry matter, and total soluble solids in both seasons. In second place was the KT treatment, which yielded the best values for fruit length and width in 2021, the best values for leaf nitrogen and iron contents and fruit weight and volume in 2022, and the best values regarding variable fluorescence by maximum fluorescence, relative chlorophyll content (SPAD readings), the photosynthetic performance index, total acidity, and vitamin C in both seasons. Furthermore, the highest total lemon yield and leaf potassium contents were achieved with the KN treatment in both seasons. The heat map illustrating that most of the studied characteristics were positively and significantly correlated with total lemon yield (TLY). Conclusions: The KN treatment, closely followed by the KC treatment, is regarded to be the best treatment for most of the studied trails.

Due to its distinctive properties, biochar (BC) achieves the most significant improvements among agricultural soil amendments. A pot experiment was performed at the Faculty of Agriculture and Natural Resources at Aswan University, Aswan province, Egypt (latitudes 24° 05ʹ 18ʺ N and longitudes 32° 54ʹ 00ʺ E) during 2022 to evaluate the effectiveness of two BCs derived from sugarcane manufacturing waste—namely, bagasse (BCBG) and filter-cake (BCFC), which were obtained at two different of pyrolysis temperatures (300 and 600 °C) at 0, 1 and 2% ~ 0.0, 50.0 and 100.0 g.pot-1 on the hydro-chemical properties of sandy soil. This study employed a split–split plot structure in a Randomized Complete Block Design with three replicates. The results indicate that applying BCFC300 had the greatest effect on organic matter content (OM) and available water content (AWC), while applying BCFC600 gave the best results for CaCO3, as well as water holding capacity (WHC) and permanent wilting point (PWP). Likewise, BCBG300 had superior effects on soil pH and cation exchange capacity (CEC) and field capacity (FC). Furthermore, all the improvements seen in all the studied hydro-chemical properties, except PWP, were associated with BC-R0 and BC-R2. In conclusion, BCBG, PYT300 and BC-R2 and their interactions were the most influential on soil chemical properties. Furthermore, the best hydrological properties (FC and AWC) in the sandy soil were obtained in the treatment without amendment. Additionally, BCFC x PYT600 x BC-R2 and BCFC x PYT600 x BC-R2 treatments were the most impactful on WHC and PWP, respectively.

Owing to its unique features, biochar (BCH) is an excellent surrogate approach to improving the chemical properties of soil with undesirable characteristics. Under multiple abiotic stresses (ECe = 10.8 vs. 10.7 dS.m−1; CaCO3 = 19.1 vs. 18.8%; soil pH = 8.15 vs. 8.13) during two growing seasons (2020/2021 and 2021/2022), an experimental pot study was conducted to investigate the potential effects of palm tree frond BCH applied at three rates (0.0, 28.0, and 56.0 g.pot−1, labeled as BCH0, BCH1, and BCH2) and generated under three pyrolysis temperatures (350, 500, and 700 °C, labeled as PYT350, PYT500, and PYT700). The experiment was set up according to a randomized complete block design. The results indicated that both the PYT700 x BCH2 and PYT700 x BCH1 treatments had the highest impact on the soil chemical properties, soil nutrient status, and leaf nutrient contents, except for the soil pH, which was positively affected by PYT350 and BCH1 in both seasons, and the available potassium content (AKC) in the first season. Regarding the germination parameters, the data reveal that PYT350 x BCH2 and PYT700 x BCH2 were the superior treatments for the germination percentage (GP) and the mean germination time (MGT), while PYT500 x BCH2 led to noteworthy elevations of seed vigor (SV) in both seasons. The heat map illustrating the studied soil chemical properties fluctuates between positive and negative. In short, the application of BCH has profoundly desirable effects on the soil chemical properties depending on the PYTs and BCH addition rates.

Water deficit is one of the major limiting factors of seed crop germination and productivity. Consequently, superabsorbent polymers (SAPs) are among several technologies that enhance water use efficiency, leading to worthy seed germination. The objective of this study was to investigate the potential effect of three rates of SAPs (0.0%, 0.5%, and 1.0% w/w) on the seedling emergence of barley and fenugreek sown in a sandy soil using three replicates in a randomized complete block design. Outdoor pot experiments were conducted in Aswan Province, Egypt. The differences in the final germination percentages (FGPs) were not significant for both seeds, while the application of SAPs enhanced the seedling germination index (GI) with significant differences for both crop seeds. The application of SAP at 0.5% gave the highest GI for barley (2.47 day⁻¹) and fenugreek (2.66 day⁻¹) seeds. The sigmoidal function effectively described the cumulative germination percentage rates for both seeds as a function of time under the SAP levels with R2 greater than 0.992. The maximum rates were 69.4 and 64.6 day⁻¹ for barley and fenugreek seeds at SAP 0.5%, respectively. The corresponding rates for 0.0% SAP were 11 and 12 day⁻¹. The water germination efficiencies (WGE) were 27.76 and 30.04 cm⁻¹ for 0.0% and 0.5% SAP for barley, while they were 23.07 and 29.9 cm⁻¹ for fenugreek. Accordingly, SAPs could represent a promising solution for increasing moisture conservation for seed germination in a sand soil. For strategic management, barley is recommended for growth over fenugreek in a semidried soil.

Background Owing to its unique features, biochar (BC) is an excellent surrogate approach to improve the chemical properties of soil with undesirable characteristics. Methods. Under multiple abiotic stresses (ECe = 10.8 vs. 10.7 dS.m⁻¹; CaCO₃ = 19.1 vs. 18.8%; soil pH = 8.15 vs. 8.13) during two growing seasons (2020/2021 and 2021/2022), an experimental pot study was conducted to investigate the potential effects of palm tree frond biochar (PTF-BC) applied at three rates (0.0, 28.0, and 56.0 g.pot⁻¹, labeled as BC₀, BC₁, and BC₂) generated under three pyrolysis temperatures (350, 500, and 700 °C, labeled as PT₃₅₀, PT₅₀₀, and PT₇₀₀). The experiment was set up according to a split-plot structure in a randomized complete block design; the pyrolysis temperatures were set as the main plot and BC addition rates were set as sub-main plots. Results. The results indicate that PT₇₀₀ and BC₂ had the most impact on soil chemical properties, except soil pH, which was positively affected by PT₃₅₀ and BC₁. Regarding the germination parameters, the data reveal that PT₃₅₀ and P₇₀₀ were the superior treatments, while BC₂ led to noteworthy elevations of all studied germination parameters, except germination rate (GR), in both seasons. The heat map illustrating the studied soil chemical properties fluctuates between positive and negative. Conclusion. In short, the application of BC has profound desirable effects on soil physio-chemical properties relying on PTs.

Soil pH is the most important factor in evaluating plant nutritional status due to its close association with nutrient availability. In the 2018 and 2019 seasons, two field experiments were conducted to evaluate the performance of olive trees (Olea europaea, Picual cv.) grown in sandy clay loam soil under multi-abiotic stresses with the application of three different acidifying agents (AAs), acetic (AC), citric (CA), and sulfuric (SA) acid, at two doses (25 and 50 cm³; AC₁ and AC₂, CA₁ and CA₂, and SA₁ and SA₂, respectively), as compared with a control treatment. This study was established according to a randomized complete block design. In general, our results showed that all the AAs applied surpassed the control treatment with respect to all the studied parameters except for the leaf iron content. Furthermore, the trees treated with CA yielded the best results in terms of the leaf nitrogen, calcium, and magnesium contents; the physiological and growth parameters (except for the performance index); the total fruit weight, flesh weight, and flesh dry matter; the fruit diameter; the oil content; and the total olive yield. Furthermore, the maximum leaf potassium, manganese, zinc, and copper contents were obtained in the trees growing in soil injected with AC. The correlation coefficient fluctuated between positive and negative among the studied characteristics.

Among soil parameters, Soil Chemical Properties (SCPs) are a crucial factor for the evaluation of chemical and fertility indices, proper decision-making regarding land reclamation, and land cultivation. In this work, 32 samples were collected from the surface (0–30 cm) and subsurface (30–60 cm) layers from 16 selected positions using GIS in the Toshka area (23°30′ and 23°60′ N latitude and 31°32′ and 31°36′ E longitude), Aswan, Egypt. Our results revealed that the soil reaction ranged from slightly (7.25) to moderately alkaline (8.19) and was characterized as a moderately saline and calcareous soil; however, the minimum ECe and CaCO₃ values exceeded 4.30 dS·m⁻¹ and 12.80%, respectively. Furthermore, there was a significant decrease in the soil organic matter (not exceeding 0.11%) and available nutrient contents. The cation exchange capacity was moderate. The correlation coefficient between the studied SCPs fluctuated between positive and negative. In brief, the area can be reclaimed through a proper reclaiming plan and the selection of the most suitable crops to treat the undesirable characteristics.