Decreasing freshwater supply has led to the consideration of treated wastewater as an alternative source for agricultural irrigation. However, the higher content of heavy metals restricts their use in agricultural purposes. In the current study, a set of 181 SSR markers were used to perform association mapping in a structured sorghum population consisting of 107 accessions evaluated under tap-water and heavy-metals-containing water irrigation conditions. Significant differences between optimal and stressed growing conditions were shown in all evaluated phenotypic traits. Association mapping revealed 14 significant associations between 12 SSR markers and heavy metals stress indices of phenotypic traits (R2 = 11.54–30.85%). BLASTP annotation of QTLs genomic sequences identified 102 gene homologs, of which 19 are known to be implicated in phytoremediation and heavy metals tolerance. All nineteen genes exhibit differential expression patterns in heavy metals tolerant and susceptible sorghum accessions, and their transcriptional levels were highly elevated under heavy metals stress, indicating a possible functional association among these genes and provides strong evidence for their role in phytoremediation and heavy metal stress tolerance. Clustering and expression patterns of pentatricopeptide repeat and zinc finger protein genes suggest crucial roles of those genes in phytoremediation and heavy metals tolerance.

Local waste recycling has many benefits to environmental, economic, social, and health aspects. Arid regions, especially calcareous sandy soil, where high rates of organic matter decomposition led carbon emission to increase, are poor in their content of organic matter and some nutrients as well as high phosphorus fixation in this soil. The objectives of this study were investigating effects of bagasse pith-vinasse biochar and incubation periods on: carbon (C) sequestration, carbon mineralization, and nutrients availability of calcareous sandy soil. The incubation experiment included four treatments: (1) unamended soil (control), (2) soil amended with 3% (w/w) bagasse pith-vinasse (BPV), (3) soil amended with 3% (w/w) biochar of bagasse pithvinasse (BPVB), and (4) soil amended with 3% (w/w) BPV + BPVB (1:1) and incubated at 3, 7, 21 and 46 days. The results of this study revealed a decline in carbon emission with adding BPVB compared to BPV and BPV + BPVB this in turn leads to enhancing carbon sequestration. Available phosphorus improved significantly with adding bagasse pith-vinasse biochar compared with unamended soil. Phosphorus availability increases with increasing incubating durations for bagasse pith-vinasse biochar. At the end of the incubation, the phosphorus availability increased from 20.08 mg kg−1 soil for control to 20.36, 35.25, and 20.63 mg kg−1 soil for BPV, BPVB and BPV + BPVB, respectively. Moreover, potassium availability showed a significant improvement with BPVB application compared with unamended soil. We recommend adding biochar to low fertility soil because it plays an important role in the environmental management via improving soil fertility, local waste management, and climate change mitigation.

The high cost and environmental problems related to the production of phosphate fertilizers as well as their excessive and continuous applications represent great challenges in modern agriculture. Therefore, we conducted an incubation experiment using sandy soil to evaluate the effects of elemental sulfur, disodium ethylene diamine tetra-acetic acid (Na2-EDTA) and their mixture with cow bone char as well as incubation periods on changes of phosphorus (P) availability, water soluble P, soil pH, electrical conductivity (EC), soluble calcium (Ca) and soluble sulfate (SO4). Applying sulfur (S), Na2EDTA and their mixture with cow bone char improved significantly phosphorus availability in soil, Olsen-P value increased from 7.65 mg kg−1 (control) to 12.20 mg kg−1 (cow bone char + sulfur), 12.80 mg kg−1 (cow bone char + Na2-EDTA) and 13.07 mg kg−1 (cow bone char + sulfur + Na2-EDTA) at the end of incubation periods While, cow bone char + sulfur + Na2- EDTA treatment lead Olsen-P to decline significantly with increasing incubation periods. Amending soil by sulfur with cow bone char treatment caused significant increase in the Olsen-P with increasing incubation periods. Cow bone char + sulfur and cow bone char + Na2-EDTA showed non-significant differences in Olsen-P. Because of the increase in phosphate fertilizer prices, the results of this study demonstrated the great potential of cow bone char usage which is a promising way to improve phosphorus availability in P-poor soil as well as being a clean alternative and renewable source of phosphate fertilizer. Consequently, we recommend utilizing cow bone char with sulfur as slow release fertilizer with time due to their low cost and it is a safe source of phosphorus in sustainable agriculture, rather than using Na2-EDTA due to its high price.

This incubation study assessed the effects of unpyrolyzed Calotropis procera and its biochar produced at different pyrolysis temperatures as well as incubation periods on carbon (C) emission, ammonia (NH3) volatilization, soil quality indicators and nutrient availability of alkaline sandy soil. Five treatments were studied in this experiment: unamended soil (CK), unpyrolyzed calotropis (UPC), calotropis biochar at 250 °C (CB250), calotropis biochar at 400 °C (CB400), and calotropis biochar at 650 °C (CB650). These amendments were applied to the soil at level of 4% (w/w). The results of this study showed that applying unpyrolyzed calotropis residues increased cumulative CO2 emission from the soil by 117.3, 239.4 and 232.0% over CB250, CB400, and CB650, respectively, by the end of incubation. Compared to the unamended soil, applying CB250 reduced cumulative NH3 volatilization in soil by 71.5%, which attributed to ammonia adsorption because of increased cation exchange capacity and decreased soil pH, but CB650 increased cumulative NH3 volatilization by 73.3% after the 3-day incubation as a result of high soil pH. The available phosphorus in soil improved significantly (p ≤ 0.01) with adding unpyrolyzed calotropis residues and its biochar produced at different pyrolysis temperatures compared to the unamended soil. The values of available phosphorus in the soil under study influenced significantly by pyrolysis temperatures of produced biochar; this is due to the pyrolysis of feedstocks increases labile phosphorus. Thenceforth, using biochar is an important strategy for enhancing carbon sequestration, decreasing ammonia volatilization and improving soil quality parameters in arid regions.

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Recent reports demonstrate that octopamine receptor (OR) agonists such as formamidine pesticides cause reproductive and developmental toxicity through endocrine disrupting effects in both humans and animals. Herein, we studied the effects of different sublethal concentrations of OR agonists, Amitraz and Chlordimeform, on growth, development, and reproduction of D. melanogaster from a genotype perspective view. As a result, the sublethal concentrations for both OR agonists delayed the developmental time including pupation and eclosion. It significantly reduced the lifespan, eclosion rate, and production of eggs. The mRNA expression of genes relevant for development and metabolism was significantly changed after exposure to sublethal concentrations of both OR agonists. Octopamine receptor in mushroom bodies (Oamb), trehalase enzyme (Treh), hemocyte proliferation (RyR), and immune response (IM4) genes were upregulated whereas, trehalose sugar (Tret1-1), mixed function oxidase enzyme (Cyp9f2), lifespan (Atg7), male mating behavior (Ple), female fertility (Ddc), and lipid metabolism (Sxe2) genes were downregulated. These results support the conclusion that OR agonists activate the octopamine receptor in D. melanogaster leading to an increase of trehalase enzyme activity and degradation of trehalose sugar into free glucose which results in rapid energy exhaustion, hyperexcitation, and disturbing of the octopaminergic system in D. melanogaster.

Abstract This study was conducted to evaluate the ability of some endophytic fungi, as biocontrol agents against sesame wilt caused by Fusarium oxysporum f. sp. sesame. Eleven fungal species belong to genus Fusarium was isolated from different localities in Sohag and Assiut governorates. All isolated species proved to be pathogenic on Giza-32 sesame cultivar. Twelve endophytic fungi isolates were isolated from some parts of various plants. The endophytic fungi isolates were tested for antagonistic activity by the dual culture and culture filtrate techniques. All endophytic fungal isolates were showed antagonistic activity againstthe causal pathogen in vitro. The endophytic Aspergillus niger was more antagonistic than other tested isolates toward the causal pathogenfollowed by A. clavatus, Penicillium chrysogenum and P. crustosum. All the tested fungal culture filtrates (FCF) were significantly affected the growth of the causal pathogen. FCF of Aspergillus terreusisolate at 20 % concentration displayed the greatest inhibitory action to the pathogen mycelia growth. Single application with endophytic fungi or combined with Trichoderma sp. were significantly deceased the disease severity (%) and increased the plant growth parameters such as shoot length, shoot weight, root weight and number of pods.

THE CURRENT study was conducted to evaluate the rooting behavior of air-layers of Buttonwood (Conocarpus erectus L.) under IBA stimulation and/or inoculation with Bacillus subtilis. Experiment contained two branch lengths (275 and 150 cm) and six treatments of IBA (100, or 200 ppm) and B. subtilis suspension (5 or 10 ml/air-layer from suspension 108 CFU/ml) added individually or in combinations. The best results were obtained by 200 ppm IBA and/or 10 ml B. subtilis resulting in the maximum rooting percentage (100%), the highest number of roots (58.66/layer), the longest root (26.50 cm), large root volume (86.46 cm3/layer), the heaviest fresh and dry roots (82.68 and 13.50 g/layer, respectively) and maximum percentage of layers showing secondary roots (100%). These results were correlated with highest total carbohydrates content (28.40%) and total phenolic compounds (52.41 mg Gallic acid equivalent/g DW). The interaction effects indicated that the superior combined treatment was occurred by shoot length of 150 cm supplied with 200 ppm IBA + B. subtilis.