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Antibiotic-resistant bacteria represent a serious public health threat. For that reason, the development of new and effective antibiotics to control pathogens has become necessary. The current study aims to search for new microorganisms expressing antibiotic production capacity. Fifteen sites covering a wide range of harsh environmental conditions in Egypt were investigated. Two hundred and eighty bacterial isolates were obtained and then tested against pathogenic bacteria using the agar disk diffusion technique. Fifty-two (18.6% of the total) of the isolates exhibited antagonistic properties, which affected one or more of the tested pathogens. The isolate 113 was identified as Bacillus licheniformis and isolate 10 was identified as Brevibacillus borstelensis using the 16S rRNA technique. The B. licheniformis strain was stronger in antibiotic production against S. typhi, M. luteus, and P. ariginosa, whereas the strain Br. borstelensis was more efficient against B. cereus, E. coli, and Klebs. sp. The sensitivity of the strains to commercial antibiotics showed that B. licheniformis was highly sensitive to seven commercial antibiotics, whereas Br. borstelensis was sensitive to nine antibiotics. The two strains were subjected to ethyl methanesulfonate (EMS) mutagenesis to obtain mutants with a higher antibiotic production. The total bacterial count was measured after treatment with EMS mutagen and showed a significant gradual increase in the antimicrobial activity, which was achieved via shaking in the presence of EMS for 60 min. High antimicrobial activities were noted with 17 and 14 mutants from the B. licheniformis and Br. borstelensis strains, respectively. The mutant B. licheniformis (M15/Amo) was more active than the parent strain against S. aureus (212.5%), while the mutant Br. borstelensis (B7/Neo) was more effective against S. typhi (83.3%). The present study demonstrates the possibility of obtaining potent antibiotic-producing bacteria in hot spring waters and further improving the indigenous bacterial capacity to produce antibiotics by using EMS mutagenesis. [ABSTRACT FROM AUTHOR]

Drought is an environmental abiotic stress that diminishes wheat production worldwide. In the present study, we evaluated fifty bread wheat genotypes (arranged in alpha lattice design) under two main water regimes, water-deficit (two surface irrigations) and well-watered (four irrigations), at different sites in two consecutive cropping seasons, 2019/20 and 2020/21. To identify the drought-tolerant genotypes, utilized several selection/phenotyping criteria, including agronomic traits, e.g., grain yield (GY) and yield components (SM); physiological parameters such as canopy temperature (CT), leaf transpiration rate (TRN), intercellular CO2 concentration (INCO); spectral reflectance indices, e.g., Leaf Chlorophyll Index (LCI), curvature index (CI), and normalized difference vegetation index (NDVI); and stress tolerance indices (STI) were determined concurrently with the grain yield. The results revealed significant differences (p ≤ 0.01) among the environments, genotypes, and their interaction for grain yield (GY), days to heading (DH), days to maturity (DM), grain filling period (GFP), grain filling rate (GFR), Normalized difference vegetation index (NDVI), plant height (PH), and spikes per square meter (SM). The genotype plus genotype by environment (GGE) and genotype by yield*trait (GYT) biplot techniques indicated that Genotype 37 (Sakha 95) and Genotype 45 performed best under well-watered and water-deficit environments. Furthermore, the same genotypes were the best from the genotype by stress tolerance indices (GSTI) approach view. Genotype 37 (Sakha 95) was superior to the GYT selection method, with physiological parameters and spectral reflectance indices. Likewise, we can identify this genotype as low-water-tolerant based on GSTI, GYT, and SRI results and recommend involving it in the drought breeding program. [ABSTRACT FROM AUTHOR]

Developing countries all over the world face numerous difficulties with regard to food security. The purpose of this research is to develop a new approach for evaluating wheat's suitability for cultivation. To this end, geographical information systems (GIS) and fuzzy inference systems (FIS) are used as the most appropriate artificial intelligence (AI) tools. Outcomes of investigations carried out in the western Nile Delta, Egypt. The fuzzy inference system used was Mamdani type. The membership functions used in this work are sigmoidal, Gaussian, and zmf membership. The inputs in this research are chemical, physical, and fertility soil indices. To predict the final soil suitability using FIS, it is required to implement 81 IF-THEN rules that were written by some experts. The obtained results show the effectiveness of FIS in predicting the wheat crop's suitability compared to conventional methods. The research region is split into four classes: around 241.3 km2 is highly suitable for wheat growth, and 224 km2 is defined as having moderate suitability. The third soil suitability class (low), which comprises 252.73 km2, is larger than the unsuitable class, which comprises 40 km2. The method given here can be easily applied again in an arid region. Decision-makers may benefit from the research's quantitative findings. [ABSTRACT FROM AUTHOR]

This work is a novel trial to integrate geostatistics with fuzzy logic under the geographic information system (GIS) environment to model soil pollution. Soil samples from seventy-one soil profiles in the northern Nile Delta, Egypt, and were analyzed for total concentrations of Cd, Co, Cu, Pb, Ni, and Zn. Metal distribution maps were generated using ordinary kriging methods. They were normalized by linear and non-linear fuzzy membership functions (FMFs) and overlain by fuzzy operators (And, OR, Sum, Product, and Gamma). The final maps were validated using the area under the curve (AUC) of the receiver operating characteristic (ROC). The best-fitted semivariogram models were Gaussian for Cd, Pb, and Ni, circular for Co and Zn, and exponential for Cu. The ROC and AUC analysis revealed that the non-linear FMFs were more effective than the linear functions for modeling soil pollution. Overall, the highest AUC value (0.866; very good accuracy) resulted from applying the fuzzy Sum overly to the non-linearly normalized layers, implying the superiority of this model for decision-making in the studied area. Accordingly, 92% of the investigated soils were severely polluted. Our study would increase insight into soil metal pollution on a regional scale, especially in arid regions. [ABSTRACT FROM AUTHOR]

One of the most significant challenges that global decision-makers are concerned about is soil contamination. It is also related to food security and soil fertility. The quality of the soil and crops in Egypt are being severely impacted by the increased heavy metal content of the soils in the middle Nile Delta. In Egypt's middle Nile Delta, fifty random soil samples were chosen. Inverse distance weighting (IDW) was used to create the spatial pattern maps for four heavy metals: Cd, Mn, Pb, and Zn. The soil contamination levels in the research area were assessed using principal component analysis (PCA), contamination factors (CF), the geoaccumulation index (I-Geo), and the improved Nemerow pollution index (In). The findings demonstrated that using PCA, the soil heavy metal concentrations were divided into two clusters. Moreover, the majority of the study region (44.47%) was assessed to be heavily to extremely polluted by heavy metals. In conclusion, integrating the contamination indices CF, I-Geo, and In with the GIS technique and multivariate model, analysis establishes a practical and helpful strategy for assessing the hazard of heavy metal contamination. The findings could serve as a basis for decision-makers to create effective heavy metal mitigation efforts. [ABSTRACT FROM AUTHOR]