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BackgroundEvaluation of native soil microbes is a realistic way to develop bio-agents for ecological restoration. Soil alkalinity, which has a high pH, is one of the most common concerns in dry and semi-arid climates. Alkaline soils face problems due to poor physical properties, which affect plant growth and crop production. A pot experiment was carried out to investigate the impact of native mycorrhizal fungi (AMF) on the wheat plant (Triticum aestivumL.) under two levels of alkalinity stress -T1 (37 mM NaHCO3), T2 (74 mM NaHCO3) - at two developmental stages (the vegetative and productive stages).ResultsAlkalinity stress significantly inhibited the germination percentage, plant biomass, photosynthetic pigments, and some nutrients (K, N, and P). Mycorrhizal inoculation improved growth parameters and productivity of wheat-stressed plants. However, lipid peroxidation was significantly lowered in mycorrhizal-inoculated plants compared to non-inoculated plants. Catalase and peroxidase were inhibited in wheat leaves and roots by alkalinity, while mycorrhiza promoted the activity of these enzymes.ConclusionThe results of this study demonstrated that alkalinity stress had highly negative effects on some growth parameters of the wheat plant, while AMF inoculation attenuated these detrimental effects of alkalinity stress at two stages by reducing the pH and Na concentration and increasing the availability of P and the productivity of wheat in particular crop yield parameters.

A reduction in crop spoilage and an increase in shelf-life is the goal of effective disease control methods. This study aimed to assess ZnO-nanoparticles (ZnO-NPs) as a safe, new protectant against Rhizopus soft rot of sweet potato. ZnO-NPs had a fungicidal effect against Rhizopus stolonifer when used at concentrations above 50 ppm. The results showed that tubers treated with ZnO-NPs exhibited fewer fungal populations (1.2 CFU per segment) than those that did not receive the treatment. Tubers infected with Rhizopus stolonifer and treated with ZnO-NPs showed no visible decay for up to 15 days, indicating that ZnO-NPs act as a coating layer on tuber surface. The greatest weight loss after 15 days of storage was reported in infected tubers (8.98%), followed by infected tubers treated with ZnO (6.54%) and infected tubers treated with ZnO-NPs (3.79%). The activity of cell-wall degrading enzymes, α-amylase and cellulase, were significantly increased in both infected tubers and those treated with ZnO, compared to the tubers treated with ZnO-NPs. These results confirm that coating with ZnO-NPs is an effective method of protecting sweet potato tubers from infection, maintaining their quality and increasing their shelf-life for up to 2 months in storage.

This work was aimed to evaluate the efficacy of arbuscular mycorrhizal fungi (AMF) and the endophytic fungal strain Epicoccum nigrum ASU11 (Epi) to control potato blackleg caused by bacterial stain Pectobacterium carotovora subsp. atrosepticum PHY7 (Pca). E. nigrum showed unique colonization frequency properties of potato plants (73.3% colonization frequency). Furthermore, the endophytic fungus exhibited antagonistic capability against pathogenic bacteria with inhibition zone 18 ± 0.5 mm. The AMF and Epi individually or in combination reduced Pca population in vivo experiment. The highest level of reduction was recorded in combination of AMF+ Epi. Also, infected potato plants treated with the two bioagents showed the highest weight of potato tubers in comparison to infected control. The enhancement of potato plants growth and the elevation of blackleg disease symptoms by bioagents (Epi + AMF) could be attributed to promoting the systemic plant resistance through the decrease of reactive oxygen species (ROS), malondialdehyde content (MDA), glutathione-s-transferase (GST), soluble peroxidase (SPO), ionic peroxidase (IPO), polyphenol oxidase (PPO), phenyl alanine ammonialyase (PAL) and lignin content. Moreover, they enhance the content of potato phenolics, superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and glutathione peroxidase (GPX) content. These results detected the potentiality of AMF and E. nigrum to promote potato growth and decrease the disease severity of blackleg disease. These biocontrol agents may have promising prospective strategies in potato crop protection and increase the feasibility of agriculture crop protection. The results reported herein are expected to provide competitive economic outcomes for sustainable cropping protection systems.

Root rot diseases of plant are accountable for crop yield losses. Biological control of this disease is considered a feasible alternative and eco-friendly method. The root rot pathogens, Exserohilum rostratum HQ905473 and Fusarium oxysporum HQ905448, were isolated from lettuce plants. Biocontrol activity of Trichoderma harzianum JF419706 and Bacillus subtilis HQ656002 against lettuce root rot and their inducibility of the defense genes were evaluated. The results confirm the efficiency of T. harzianum and B. subtilis either singly or as a mixture in the control of the disease and alleviation of the negative effect of the pathogens on lettuce plants. The phytosanitary parameters of the plants, including plant height and weight, was greatly enhanced as a result of the application of bioagents. Content of photosynthetic pigments and primary metabolites (carbohydrates, proteins and proline) significantly increased in the treated plants. The Differential display PCR reaction (DD-PCR) revealed that 15 up- and down-regulated genes were detected in the treated plants. Among these genes, the encoded GTPase activating protein, that is an important gene in the plant defense mechanism, was identified. Gene expression was analyzed in inoculated plants after 25 and 50 days. The 50-day-old plants had a higher level of gene expression than the 25-day-old plants. The results confirmed the efficiency of the bioagents in enhancing the defense mechanism of plants against the disease and ensure the sustainability of this resistance throughout the life of the plant.

The current study purposed to improve vegetative growth, nodules formation and biological dinitrogen fixation of Vicia faba L. (faba bean) grown in sandy soil by inoculation with bacterial feather hydrolysate fertilizer (BFH) and arbuscular mycorrhizal fungi (AMF). A potent feather-degrading bacterium was isolated from chicken feathers and molecular identified as Bacillus licheniformis ASU (Accession number KF446641 ). Two different native AMF were recovered from the sandy soil and identified as Acaulospora bireticulata and Glomus caesaris. Bacillus licheniformis has the capability to degrade the chicken feathers efficiently. Furthermore, it can solubilize tricalcium phosphate and produce ammonia and IAA (indole acetic acid). Faba bean seeds were grown in pot experiments containing sandy soil inoculated with AMF or BFH individually or in combination. The application of AMF and BFH in combination significantly increased nodule formation and N2-fixation. The total dry biomass of plants co-inoculated with AMF and BFH was increased significantly compared with non-inoculated plants. So, the combination with AMF and BFH has the potential to be developed as a useful biofertilizer in future. This paper is expected to afford a competitive economic outcome for sustainable cropping systems.

Intracellular synthesis of silver/silver chloride nanoparticles (Ag/AgCl-NPs) using Meyerozyma guilliermondii KX008616 is reported under aerobic and anaerobic conditions for the first time. The biogenic synthesis of Ag-NP types has been proposed as an easy and cost-effective alternative for various biomedical applications. The interaction of nanoparticles with ethanol production was mentioned. The purified biogenic Ag/AgCl-nanoparticles were characterized by different spectroscopic and microscopic approaches. The purified nanoparticles exhibited a surface plasmon resonance band at 419 and 415 nm, confirming the formation of Ag/AgCl-NPs under aerobic and anaerobic conditions, respectively. The planes of the cubic crystalline phase of the Ag/AgCl-NPs were confirmed by X-ray diffraction. Fourier-transform infrared spectra showed the interactions between the yeast cell constituents and silver ions to form the biogenic Ag/AgCl-NPs. The intracellular Ag/AgCl-NPs synthesized under aerobic condition were homogenous and spherical in shape, with an approximate particle size of 2.5-30nm as denoted by the transmission electron microscopy (TEM). The reaction mixture was optimized by varying reaction parameters, including temperature and pH. Analysis of ultrathin sections of yeast cells by TEM indicated that the biogenic nanoparticles were formed as clusters, known as nanoaggregates, in the cytoplasm or in the inner and outer regions of the cell wall. The study recommends using the biomass of yeast that is used in industrial or fermentation purposes to produce Ag/AgCl-NPs as associated by-products to maximize benefit and to reduce the production cost.

This study aims to evaluate the correlation between fungi causing paint deterioration and air contamination in Assiut University hospital to give a complete picture for the fungal quantity and spec...

This study intended to determine the ability of endophytic bacteria recovered from root nodules of Cicer arietinum L. and Vigna unguiculata L. (Walp.) plants to synthesize exopolysaccharide (EPS) and to enhance the production by changing nutritional factors. Twenty endophytic bacteria isolated from root nodules of Cicer arietinum and Vigna unguiculata were tested for their production of EPS. High EPS-producing isolates were identified on phenotypic and genotypic characteristics. Among 20 isolates, Stenotrophomonas maltophilia (C6) and Brevibacillus parabrevis (V4) isolated from root nodules of Cicer arietinum and Vigna unguiculata produced a high EPS yield in comparison with other isolates. Using 1% of sucrose as sole carbon source increases the concentration of EPS produced by S. maltophilia and B. parabrevis (65 and 107%, respectively). EPS produced by S. maltophilia and B. parabrevis was increased by the addition of fructose and lactose (0.1%). Addition of 1.68 g/L KNO3 or 2.49 g/L glycine to modified yeast extract mannitol medium (YEMB) significantly increased EPS production by S. maltophilia and B. parabrevis. Furthermore, the presence of Fe3O4 nanoparticles (25–50 µg/mL) in the modified YEMB medium increased EPS yield by B. parabrevis. Chemical characterization of EPS by GC–MS and FTIR indicate that the EPS biochemical composition is dependent on the bioavailability of carbon substrates and is controlled by limiting nutrients. The combination of the best two carbon sources sucrose (0.9%) and fructose or lactose (0.1%) in the presence of KNO3 or glycine as the best nitrogen sources significantly increased EPS yield of S. maltophilia and B. parabrevis, respectively.

The research work investigates the impact of the interaction between several rates of compost and microorganisms (bacteria, fungi, mycorrhiza) and their residual effects on growth and metals (Cd and Ni) uptake in carrot (Daucus carota L.) and jew´s mallow (Corchorus olitorius L.) grown thereafter. Soil samples were collected from agricultural areas near the superphosphate factory and used for the pot experiments. Microorganisms were isolated from the area under study of which four fungal isolates (Aspergillus niger, A. terreus, Penicillium funiculosum and Fusarium culmorum), one bacterial species (Bacillus sp.) and four species of arbuscular mycorrhizal fungi (AMF) (Acaulospora bireticulata, Gigaspora margarit, Glomus lamellosum and Glomus mosseae) were used for inoculations in the pot experiments. Also, four compost rates were applied equivalent to 0, 5, 10, 15 t ha-1 dry compost. The application of amendments increased the biomass of carrot and jew´s mallow plants. The highest reduction of Cd and Ni contents in both plants were observed by the simultaneous applications of compost with microbes or AMF to polluted soils. The DTPA extractable values of Cd and Ni in soils of jew´s mallow plants were higher those of carrot plants. The transfer factor (TF) for Cd and Ni in both plants decreased significantly (p

Nanotechnology monitors a leading agricultural controlling process, especially by its miniature dimension, opening up a number of scopes providing great opportunities for novel applications in agricultural industries. Green nanotechnology is a multidisciplinary field that has emerged as a rapidly developing research area, serving as an important technique that emphasizes on making the procedure clean, non-hazardous, and especially eco-friendly, in contrast with chemical and physical methods currently employed for nanosynthesis. However, the interaction of efficient engineered nanomaterials with plants generally results in several physiological, morphological, and genotoxic changes, and their mechanistic understanding is very crucial for their wise effective use in agriculture fields. Most importantly, scientists indicated that both positive and negative responses of nanoparticles on plant growth and development depend upon different factors including the physicochemical properties of those nanomaterials, size, shape, surface charges, mode of action, and the way of application as well as the type of plant species. For this reason, it is evident that more investigations are urgently required to know the most reliable nanoparticle type, size, concentration, the uptake mode, translocation and movement, toxicity profile, and mode of application to enable its wise application on a large scale for crop improvement. Consequently, the main emphasis has been given on the current status and future challenges related to the wide-scale fabrication of different types of green produced nanoparticles for different applications particularly in agriculture.

Soil salinity limits wheat growth, but several fungal species can promote the productivity under saline conditions. This study investigated how Arbuscular mycorrhizal fungi (AMF), and Penicillium funiculosum and Fusarium oxysporum (PFFO) affected wheat growth under saline conditions. Wheat, inoculated with AMF, or PFFO, or with AMF and PFFO, was stressed with 75, or 150 mM NaCl in the soil. AMF colonization, grain yield, shoot and root dry weights, nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), sodium (Na), and chloride (Cl), relative permeability, chlorophyll and proline contents and root malondialdehyde (MDA) were determined. Salinity limited the grain yield, and reduced N, P and K uptake and chlorophyll content. As soil salinity increased, shoot Na and Cl contents, relative permeability and proline content, and MDA increased. PFFO enhanced root colonization with AMF, N and P uptake and AMF significantly increased N, P and K uptake and chlorophyll content and decreased proline, Na, Cl and MDA contents. Compared to AMF, or PFFO, dual inoculation with AMF and PFFO decreased shoot Na and Cl uptake, increased chlorophyll, shoot N and P contents and K/Na ratio and resulted in approximately 25, 35 and 43% higher grain yield at 0, 75 and 150 mM NaCl, respectively. Data showed that Penicillium funiculosum and Fusarium oxysporum promoted AMF symbiotic effects and alleviated the deleterious effects of NaCl salts on wheat growth.

The current study sought to explore the response of application of purified silver nanoparticles (Ag NPs) to soil grown with faba bean ( Vicia faba L.) and inoculated either with Rhizobium leguminosarum bv. viciae ASU ( KF670819 ) or Glomus aggregatum 14G or in combination. Ag NPs was synthesized and stabilized using PVP and characterized by UV–vis spectroscopy and the characteristic surface plasmon resonance band centered at 430 nm. Also, the morphologies and structures of Ag NPs were characterized by X-ray diffraction and transmission electron microscopy and the size distribution ranged from 5 to 50 nm. In the first experiment, the germination and seedling growth of faba bean plants were tested under different concentrations of Ag + as AgNO 3 and Ag NPs (100–900 μg kg −1 soil). The germination declined by 40% when exposed to Ag NPs at concentration 800 μg kg −1 soil, while the same level from Ag + completely inhibited seed germination. In the second experiment the effect of a high concentration of Ag NPs (800 μg kg −1 soil) on R. leguminosarum bv. viciae growth and G. aggregatum activity in soil and their symbiosis with faba bean was investigated. It was proved that Ag NPs considerably retarded the process of nodulation, nitrogenase activity, mycorrhizal colonization, mycorrhizal responsiveness and glomalin content. High concentration of Ag NPs (800 μg kg −1 soil) resulted in detectable alterations including the intracellular deterioration of cytoplasmic components by means of autophagy and disintegration of bacteroids. These findings elucidate the mechanism of toxic action of Ag NPs which resulted in early senescence of root nodules.

Information about arbuscular mycorrhizal fungi (AMF) was abstracted based on an intensive search of publications, thesis, and preliminary annotated checklists and compilations. By screening all available sources of information, it was possible to report forty-eight taxa belonging to one class (Glomeromycetes), four orders (Archaeosporales, Diversisporales, Glomerales and Paraglomerales) and six families (Acaulosporaceae, Archaeosporaceae, Entrophosporaceae, Gigasporaceae, Glomeraceae and Pacisporaceae). Order Glomerales accommodates the greatest range of species (28 species), the order Archaeosporales and Paraglomerales accommodate the lowest range (one species each).

Cellulosic date palm wastes may have beneficial biotechnological applications for eco-friendly utilization. This study reports the isolation of thermophilic cellulase-producing bacteria and their application in lactic acid production using date palm leaves. The promising isolate was identified as Paenibacillus alvei by 16S rRNA gene sequencing. Maximum cellulase production was acquired using alkaline treated date palm leaves (ATDPL) at 48 h and yielded 4.50 U.mL-1 FPase, 8.11 U.mL-1 CMCase, and 2.74 U.mL-1 β-glucosidase. The cellulase activity was optimal at pH 5.0 and 50°C with good stability at a wide temperature (40-70°C) and pH (4.0-7.0) range, demonstrating its suitability in simultaneous saccharification and fermentation. Lactic acid fermentation was optimized at 4 days, pH 5.0, 50°C, 6.0% cellulose of ATDPL, 30 FPU/ g cellulose, 1.0 g. L-1 Tween 80, and 5.0 g. L-l yeast extract using Lactobacillus delbrueckii. The conversion efficiency of lactic acid from the cellulose of ATDPL was 98.71%, and the lactic acid productivity was 0.719 g. L-1 h-1. Alkaline treatment exhibited a valuable effect on the production of cellulases and lactic acid by reducing the lignin content and cellulose crystallinity. The results of this study offer a credible procedure for using date palm leaves for microbial industrial applications.

Arbuscular mycorrhizal fungi (AMF) can promote plant growth and reduce plant uptake of heavy metals. Phosphorus (P) fertilization can affect this relationship. We investigated maize (Zea mays L.) uptake of heavy metals after soil AMF inoculation and P fertilization. Maize biomass, glomaline and chlorophyll contents and uptake of Fe, Mn, Zn, Cu, Cd and Pb have been determined in a soil inoculated with AMF (Glomus aggregatum, or Glomus intraradices) and treated with 30 or 60 µg P-K

Intracellular synthesis of silver/silver chloride nanoparticles (Ag/AgCl-NPs) using

DATA are used to re-assess the relationships between certain species of the genus Launaea Cass. belonging to the family Asteraceae. Taxonomic diversity of 10 taxa belonging to 8 species and 2 subspecies of Launaea Cass. is provided using morphological criteria concerned with vegetative and reproductive organs in addition to FTIR spectroscopy. Ecofriendly silver nanoparticles were synthesized from Launaea’s capitula extract and characterized by FTIR spectroscopy. NTSYS-pc software was used in order to analyze the data of FTIR spectroscopy and morphological characters. FTIR technique was used to recognize the functional groups of the active compound according to the peak value in Infrared radiation region. Cluster analysis based on FTIR data divided the ten studied taxa into three major groups; the first group comprises the four species of sect. Microrhynchus (L. nudicaulis, L. intybacea and L. massauensis) and sect. Launaea (L. capitata), the second group comprises the four subspecies of L. angustifolia and L. fragilis; the third group comprises the two-allied species (L. mucronata and L. cassiniana). FTIR technique found to be a rapid and accurate method for differentiating between Launaea taxa under investigation.

In this study, a fungal isolate was isolated from avocado fruit collected from a market in Makkah city, Saudi Arabia, and identified as Neopestalotiopsis clavispora ASU1. The biomass of Neopestalotiopsis clavispora ASU1 was used as a natural bio-sorbent for removal of Cd(II) and Zn(II) from aqueous solutions. Characterization of fungal biomass was performed using Fourier transform infrared spectroscopy, X-ray Diffractometer, and BET surface area. Different factors on Cd(II) and Zn(II) biosorption were studied to evaluate the maximum conditions for metals biosorption. The (qmax) for Cd(II) and Zn (II) by N. clavispora ASU1 calculated from the Langmuir adsorption isotherm was 185.3 ± 0.25 and 153.8 ± 0.21 mg/g, respectively. Based on r2, the equilibrium biosorption isotherms fitted well with Langmuir model than Freundlich isotherm. The adsorption kinetics was studied, and the biosorption followed to the pseudo-second-order model. Thus, the current study indicated that the biomass of N. clavispora ASU1 is an effective adsorbent for the removal of heavy metals from aqueous solutions.

Supplemental material, Supplementary data for Fungi-induced paint deterioration and air contamination in the Assiut University hospital, Egypt by Ismail R. Abdel-Rahim, Nivien A. Nafady, Magdy M. K. Bagy, Mohamed H. Abd-Alla and Ahmad M. Abd-Alkader in Indoor and Built Environment

The current study was designed to improve riboflavin production utilizing the filamentous fungus Aspergillus terreus. The effect of different nutritional and environmental factors was carried out by applying one-factor-at-a-time method. The selected high producer fungal strain was identified on the bases of the sequences of the gene encoding 18S rRNA and designated as A. terreus ASU1 (KP793450). In order to investigate the quantitative, optimal levels and the reciprocal interactions between five main medium components, response surface methodology (RSM) was subsequently employed. The results proved that optimal concentrations for enhancement of riboflavin production were: corn starch 30 (g/l); tryptone 0.5 (g/l) and 1 (g/l) for each glycine, KH2PO4 and MgSO4. The maximum riboflavin production of 344.60 mg/l (predicted 342.86 mg/l) was determined under the optimal conditions and the regression analysis (R 2) of RSM showed 97.7 %. In comparison to the production of original level (63 mg/l), 5.4-fold increase had been obtained.

Aml I Mekkawy,1 Mohamed A El-Mokhtar,2 Nivien A Nafady,3 Naeima Yousef,3 Mostafa A Hamad,4 Sohair M El-Shanawany,5 Ehsan H Ibrahim,5 Mahmoud Elsabahy5–8 1Department of Pharmaceutics and Clinical Pharmacy, Faculty of Pharmacy, Sohag University, Sohag, 2Department of Microbiology and Immunology, Faculty of Medicine, 3Department of Botany and Microbiology, Faculty of Science, 4Department of Surgery, Faculty of Medicine, 5Department of Pharmaceutics, Faculty of Pharmacy, 6Assiut International Center of Nanomedicine, Al-Rajhi Liver Hospital, Assiut University, Assiut, Egypt; 7Laboratory for Synthetic-Biologic Interactions, Department of Chemistry, Texas A&M University, College Station, TX, USA; 8Misr University for Science and Technology, 6th of October, Egypt Abstract: In the present study, silver nanoparticles (AgNPs) were synthesized via biological reduction of silver nitrate using extract of the fungus Fusarium verticillioides (green chemistry principle). The synthesized nanoparticles were spherical and homogenous in size. AgNPs were coated with polyethylene glycol (PEG) 6000, sodium dodecyl sulfate (SDS), and β-cyclodextrin (β-CD). The averaged diameters of AgNPs were 19.2±3.6, 13±4, 14±4.4, and 15.7±4.8 nm, for PEG-, SDS-, and ß-CD-coated and uncoated AgNPs, respectively. PEG-coated AgNPs showed greater stability as indicated by a decreased sedimentation rate of particles in their water dispersions. The antibacterial activities of different AgNPs dispersions were investigated against Gram-positive bacteria (methicillin-sensitive and methicillin-resistant Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli) by determination of the minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs). MIC and MBC values were in the range of 0.93–7.5 and 3.75–15µg/mL, respectively, which were superior to the reported values in literature. AgNPs-loaded hydrogels were prepared from the coated-AgNPs dispersions using several gelling agents (sodium carboxymethyl cellulose [Na CMC], sodium alginate, hydroxypropylmethyl cellulose, Pluronic F-127, and chitosan). The prepared formulations were evaluated for their viscosity, spreadability, in vitro drug release, and antibacterial activity, and the combined effect of the type of surface coating and the polymers utilized to form the gel was studied. The in vivo wound-healing activity and antibacterial efficacy of Na CMC hydrogel loaded with PEG-coated AgNPs in comparison to the commercially available silver sulfadiazine cream (Dermazin®) were evaluated. Superior antibacterial activity and wound-healing capability, with normal skin appearance and hair growth, were demonstrated for the hydrogel formulations, as compared to the silver sulfadiazine cream. Histological examination of the treated skin was performed using light microscopy, whereas the location of AgNPs in the skin epidermal layers was visualized using transmission electron microscopy. Keywords: silver nanoparticles, green synthesis, coating agents, hydrogel, wound healing, antibacterial activity

Studying of nanoparticle structures is gaining momentum because of their great potential in improving several fields of science such as agriculture. The water soluble fraction of the extracellular polysaccharides (EPS)/matrix of the highly EPS producing cyanobacterium Nostoc commune have been used as a potent reducing and capping agent for green synthesis of silver nanoparticles. The size of these nanoparticles with the EPS coat was found to be in the range of 15-54 nm as analyzed using transmission electron micrographs. Interestingly, after washing the EPS coated silver nanoparticles by ethanol, the size of nanoparticles reduced to less than 15 nm due to the formation of silver oxide nanoparticles and removal of the EPS coat. Silver nanoparticles showed antibacterial properties against Escherichia coli. The minimum inhibitory concentration (MIC) was 0.012 mg/ml while the minimum bactericidal concentration (MBC) was 0.016 mg/ml. The slight difference between the MIC and MBC suggests that such silver nanoparticles act as a potent bactericidal agent against E. coli. Presoaking seeds of crop plants (Sorghum and broad bean) in five-fold MBC of silver nanoparticles (0.08 mg/ml) did not adversely affect the germination of Vicia faba L. and Sorghum bicolor plants. Concomitantly, such fivefold MBC concentration of silver nanoparticles was powerful sterilizing agent for seeds and grains against seed/grain-borne microorganisms. The results showed gradual depletion of the total colony forming units (CFU) in seeds and grains sterilized with silver nanoparticles than those sterilized with chlorine. These results suggest that the water soluble fraction of the extracellular polysaccharides (EPS)/matrix of Nostoc commune can be used as a potent reducing and capping agent for green synthesis of silver nanoparticles and that silver nanoparticles can be used as a potent surface sterilizing agent of seed crops against phytopathogenic fungi.

Root rot and charcoal rot diseases caused by Macrophomina phaseolina are the major factors that affect the growth of sunflower plants. The aim of this work was to manage these diseases by employing an effective mutual strategy, in which an antagonistic and growth-promoting yeast Brettanomyces naardensis was combined with arbuscular mycorrhizal fungi (AMF), inoculated into the soil and cultivated with the crop. The results demonstrated that B. naardensis is a potent biocontrol agent for M. phaseolina that colonizes fungal hyphae, causing malformation and damage. In vitro, the yeast produced indole acetic acid and ammonia and showed good phosphate solubilization activity, confirming its growth-promoting characteristics. Dual inoculation of sunflower plants with both yeast and AMF involved in a reduction of the disease incidence of root rot and charcoal rot, caused by M. phaseolina, to 11.11% and 5.55%, respectively. Inoculation with yeast and AMF significantly enhanced growth parameters (plant height, dry weight and leaf number) in both healthy and infected plants. The results approved the induction of the immune system in sunflower plant via decreasing malondialdehyde content (MDA) and increasing the nutrient availability by dual inoculation with yeast and AMF that was confirmed by the enhancement of plant growth and alleviation of the disease symptoms. The double bioagents offer a promising biocontrol strategy in crop protection as a biofungicide and biofertilizer together in one bioformulation.

Plant-associated microorganisms play a critical role in agricultural productivity. Symbiotic microorganisms interact with each other and allow their host leguminous plants to maintain optimal nutrient levels and enhance their growth. Therefore, the goal of the current study was to investigate the synergistic interaction of different symbiotic microbes and its beneficial effect on the nodulation, nodule efficiency, and growth of salt-affected chickpea plants (Cicer arietinum L.). Rhizobium sp. (MK358859) was isolated from the root nodules of chickpea plants. In vitro, magnetite nanoparticles (Fe3O4-NPs) at a concentration of 150 μg/ml significantly enhanced the growth ofRhizobium compared with bulk FeCl3. The impact of seven soil salinity levels (0, 25, 50, 75, 100, 150, and 200 mM NaCl) on germination and subsequent growth was measured. The salinity levels ranging from 25 to 150 mM significantly inhibited the growth of chickpea plants, while the 200 mM level hindered their germination. The influence of triple microbial inoculation of chickpea plants grown in soil with 0, 75 and 150 mM NaCl was studied. Inoculation with mycorrhizal fungi, Fe3O4 NP-inducedRhizobium, and endophytic Stenotrophomonas maltophilia significantly improved the nodulation, leghaemoglobin content, nitrogenase activity, and growth of chickpea grown at salinity level of 75 and 150 mM compared with the controls. The mitigation of the destructive effect of salinity stress was due to improvement in the nutritional status of plants as determined by their K, P, carbohydrate and protein contents. Such triple microbial inoculation could be a successful bio-fertilizer that can contribute to protecting chickpea plants from salinity by attenuating salt-induced oxidative damage.

Microbial synthesis of β-carotene has gained more interest as an alternative to synthetic β-carotene due to easy extraction and high yield. The vitamin microbial production is mainly dependent on culture conditions and the medium compositions. In this study, the β-carotene production by the Rhodotorula glutinis ASU6 (KU550702) was evaluated under different growth conditions and nutrient composition. Different agro-renewable wastes were tested as carbon source for R. glutinis to obtain maximum amount of β-carotene. Meanwhile, it is clear that R. glutinis could grow well on acid extract of onion peels and produced large amount of β-carotene. Initial statistical screening using a Plackett-Burman design showed temperature, incubation time, fermentation type, non-treated onion waste, KH2PO4 and L-asparagine as significantly, influencing β-carotene production. Response surface methodology was applied to determine the mutual interactions between these parameters and optimal levels for β-carotene production. The maximum value of β-carotene production was 204.29 mg/l (7.5-fold) of value observed as central point of the central composite design. All the experimental data are in good agreement with predicted ones, confirming the responsibility of the proposed empirical model in describing β-carotene production by R. glutinis. In the whole, the outcomes of this study support the exploitation of onion peels through microbial fermentation for β-carotene production.

Since Pier Antonio Micheli described and published on the genus Aspergillus in Nova Plantarum Genera in 1729 the genus has attracted an immense interest. Aspergillus is a diverse genus occurring worldwide, species from this genus are considered to primarily be terricolous with important roles as decomposers of organic materials and cause destructive rots in agricultural products and the food industry, where they produce a wide range of mycotoxins. The genus currently contains 339 accepted species and its economic and historical importance makes it remain at center stage in future discussions about nomenclature and mycological diversity. The International Commission of Penicillium and Aspergillus voted to maintain a broad generic concept for Aspergillus . Eleven teleomorphs associated with Aspergillus anamorphs in which seven genera ( Eurotium, Neosartorya, Emericella, Chaetosartorya, Hemicarpenteles, Sclerocleista , and Warcupiella ) are maintained and four genera ( Fennellia, Petromyces, Neocarpenteles , and Neopetromyces ) are synonymized. Therefore, together with its ubiquitous nature, these species have greatly significant impacts on ecosystems, agriculture, food production, biotechnology, and human and animal health. The goal of this chapter is to represent the biodiversity of genus Aspergillus in a wide range of environmental habitats including deserts, salterns, agricultural, polar, aquatic, mangrove, living plants and animals, air, decayed wood, stones, and human.

Biological green synthesis of silver nanoparticles (AgNPs) from silver salts is a growing advanced approach to avoid the requirement of costly instruments and involvement of hazardous chemicals as well. However, increasing use of AgNPs raises potential toxicity level in the environment. In this investigation, leaf extract of rosemary (Rosmarinus officinalis) used as a reducing and stabilizing agent for biosynthesis of AgNPs. The biosynthesized AgNPs were authorized by UV-vis spectrophotometer and X-ray diffraction (XRD) analysis. The shape and size of the biosynthesized AgNPs were studied using high resolution transmission electron microscope (TEM). The toxicity of the biosynthesized silver nanoparticles on wheat and tomato plants was studied by soaking wheat grains and tomato seeds in 100 mg/L AgNPs and follow its effect on seedling growth of wheat (at 10 days) and on vegetative growth of tomato and wheat plants (at 35 days). Some physiological parameters as germination percentage of wheat seedling, length of seedling, dry weight, pigment fractions (chl.a, chl.b and caroteinoids), soluble proteins, lipid peroxidation (MDA) and antioxidant enzymes (catalase and peroxidase) of two plants were measured. AgNPs has a non-significant inhibitory effect on germination percentage of wheat, dry weight and pigment fractions. The biosynthesized AgNPs has a noticeable stress effect on tomato plant as reduced chlorophyll a and dry weight. Generally, AgNPs stimulate MDA accumulation in tomato and wheat plants. There was a noticeable different effect of AgNPs on soluble proteins and antioxidant enzymes as catalase and peroxidase among tomato and wheat plants.

The land snailEobania vermiculatais an important crop pest causing considerable damage in agriculture. The aim of the present work is to evaluate the possibilities of using silver nanoparticles (AgNPs) to control the land snail. The AgNPs have been synthesized biologically using white radish (Raphanus sativusvar.aegyptiacus). The biosynthesis was regularly monitored by UV-Vis spectroscopy. X-ray diffraction spectra revealed peaks of crystalline nature of AgNPs and the transmission electron micrographs further confirmed the size of the synthesized nanoparticles ranging from 6 to 38 nm. The exposure of the snails and soil matrix to AgNPs in a laboratory experiment reduced the activity and the viability of the land snail (20% of AgNPs treated snails died) as well as the frequency of fungal population in the surrounding soil. Moreover histology and ultrastructure alterations have been found in both kidney and the digestive gland of AgNPs treated land snails. The synergistic effect of synthesized AgNPs as antifungal was evaluated and clearly revealed that AgNPs can be effectively used against various plant pathogenic fungi. The present study results may open a new avenue to use the snail as bioindicator organism of environmental pollution.

Mycoremediation is an on-site remediation strategy, which employs fungi to degrade or sequester contaminants from the environment. The present work focused on the bioremediation of soils contaminated with zinc by the use of a native mycorrhizal fungi (AM) called Funneliformis geosporum (Nicol. & Gerd.) Walker & Schüßler. Experiments were performed using Triticum aestivum L. cv. Gemmeza-10 at different concentrations of Zn (50, 100, 200 mg kg-1) and inoculated with or without F. geosporum. The results showed that the dry weight of mycorrhizal wheat increased at Zn stressed plants as compared to the non-Zn-stressed control plants. The concentrations of Zn also had an inhibitory effect on the yield of dry root and shoot of non-mycorrhizal wheat. The photosynthetic pigment fractions were significantly affected by Zn treatments and mycorrhizal inoculation, where in all treatments, the content of the photosynthetic pigment fractions decreased as the Zn concentration increased in the soil. However, the level of minerals of shoots, roots, and grains was greatly influenced by Zn-treatment and by inoculation with F. geosporum. Treatment with Zn in the soil increased Cu and Zn concentrations in the root, shoot and grains, however, other minerals (P, S, K, Ca and Fe) concentration was decreased. Inoculation of wheat with AM fungi significantly reduced the accumulation of Zn and depressed its translocation in shoots and grains of wheat. In conclusion, inoculation with a native F. geosporum-improves yields of wheat under higher levels of Zn and is possible to be applied for the improvement of zinc contaminated soil.

Egyptian soils are generally characterized by slightly alkaline to alkaline pH values (7.5-8.7) which are mainly due to its dry environment. In arid and semi-arid regions, salts are less concentrated and sodium dominates in carbonate and bicarbonate forms, which enhance the formation of alkaline soils. Alkaline soils have fertility problems due to poor physical properties which adversely affect the growth and the yield of crops. Therefore, this study was devoted to investigating the synergistic interaction of Rhizobium and arbuscular mycorrhizal fungi for improving growth of faba bean grown in alkaline soil. A total of 20 rhizobial isolates and 4 species of arbuscular mycorrhizal fungi (AMF) were isolated. The rhizobial isolates were investigated for their ability to grow under alkaline stress. Out of 20 isolates 3 isolates were selected as tolerant isolates. These 3 rhizobial isolates were identified on the bases of the sequences of the gene encoding 16S rRNA and designated as Rhizobium sp. Egypt 16 (HM622137), Rhizobium sp. Egypt 27 (HM622138) and Rhizobium leguminosarum bv. viciae STDF-Egypt 19 (HM587713). The best alkaline tolerant was R. leguminosarum bv. viciae STDF-Egypt 19 (HM587713). The effect of R. leguminosarum bv. viciae STDF-Egypt 19 and mixture of AMF (Acaulospora laevis, Glomus geosporum, Glomus mosseae and Scutellospora armeniaca) both individually and in combination on nodulation, nitrogen fixation and growth of Vicia faba under alkalinity stress were assessed. A significant increase over control in number and mass of nodules, nitrogenase activity, leghaemoglobin content of nodule, mycorrhizal colonization, dry mass of root and shoot was recorded in dual inoculated plants than plants with individual inoculation. The enhancement of nitrogen fixation of faba bean could be attributed to AMF facilitating the mobilization of certain elements such as P, Fe, K and other minerals that involve in synthesis of nitrogenase and leghaemoglobin. Thus it is clear that the dual inoculation with Rhizobium and AMF biofertilizer is more effective for promoting growth of faba bean grown in alkaline soils than the individual treatment, reflecting the existence of synergistic relationships among the inoculants.