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Abbas, M. T., M. A. Hamza, H. H. Youssef, G. H. Youssef, M. Fayez, M. Monib, and N. A. Hegazi, "Bio-preparates support the productivity of potato plants grown under desert farming conditions of north Sinai: Five years of field trials", Journal of Advanced Research, vol. 5, issue 1, pp. 41 - 48, 2014. AbstractWebsite

Organic agriculture as well as good agricultural practices (GAPs) intrigues the concern of both consumers and producers of agricultural commodities. Bio-preparates of various rhizospheric microorganisms (RMOs) are potential sources of biological inputs supporting plant nutrition and health. The response of open-field potatoes to the application of RMO bio-preparates, the biofertilizer "Biofertile" and the bioagent "Biocontrol", were experimented over 5 successive years under N-hunger of north Sinai desert soils. Both vegetative and tuber yields of a number of tested cultivars were significantly improved due to rhizobacterial treatments. In the majority of cases, the biofertilizer "Biofertile" did successfully supply ca. 50% of plant N requirements, as the yield of full N-fertilized plants was comparable to those received 50% N simultaneously with bio-preparates treatment. The magnitude of inoculation was cultivar-dependent; cvs. Valor and Oceania were among the most responsive ones. Bio-preparate introduction to the plant-soil system was successful via soaking of tubers and/or spraying the plant canopy. The "Biocontrol" formulation was supportive in controlling plant pathogens and significantly increased the fruit yields. The cumulative effect of both bio-preparates resulted in tuber yield increases of ca. 25% over control. © 2014 .

Abbas, M., M. Monib, A. Rammah, M. Fayez, and N. Hegazi, "Intercropping of sesbania (sesbania sesban) and leucaena (leucaena leucocephala) with five annual grasses under semi-arid conditions as affected by inoculation with specific rhizobia and associative diazotrophs", Agronomie, vol. 21, issue 6-7, pp. 517 - 525, 2001. AbstractWebsite

Intercropping of legumes and non-legumes is considered to improve the quality and quantity of field forage crops. Under semi-arid desert conditions, intercropping of leucaena and sesbania with some annual grasses (barley, pearl millet, and Rhodes-, ryeand sudan-grasses) was evaluated in a series of field trials. Inocula of specific rhizobia for legumes and a composite of associative diazotrophs for non-legumes were applied in the presence or absence of N fertilizers. Rhizobia inoculation was indispensable, and supported better growth of legumes which extended to the neighboring non-legumes. Associative diazotrophs improved biomass and N yields of non-legumes, particularly in the presence of moderate N fertilization for winter barley and rye grass and of higher doses of 300 kg N·ha-1 for summer pearl millet and sudan grass. Intercropping improved productivity of non-legumes, in particular barley mixed with sesbania, and the calculated N-transfer from legumes to non-legumes ranged from 20 to 70 kg N·ha-1.

Ahmed, R. H., H. M. Badawi, A. S. Ali, and M. Fayez, "Growth performance of rhizobacteria on water hyacinth (Eichhornia crassipes) juices and dehydrated powder", Egyptian Journal of Aquatic Research, vol. 44, issue 1, pp. 1 - 7, 2018. AbstractWebsite

In the present study, juice of water hyacinth (Eichhorina crassipes), either crude or from its successive dilutions (1:1, 1:10, 1:30, 1:50 v/v) supported the in vitro development of Bacillus megaterium, Bacillus subtilis, Azotobacter chroococcum and Rhizobium leguminosarum biovar Phaseoli with doubling time (23.1–63.0 min) which was comparable if not shorter, to that calculated using the standard laboratory -synthetic media (nutrient, N-deficient mannitol and yeast extract agar media; 48.0–64.8 min). Rhizospheric microorganisms of legume and non-legume plants successfully grew on surface-inoculated agar plates of crude and diluted juices of the macrophyte. Tea bags filled with the dehydrated powders (5 and 10 g l−1) of water hyacinth supported the in situ recoverability of total rhizobacteria in population densities (3 × 107 - >108 cfu.g−1), which were found to be comparable, if not excessive, to those enumerated on the recommended culture media. Morpho-physiological identification of some isolates that had developed on the plant juice and tea bag culture media, revealed that they are not akin to those cultured on the chemically-synthetic culture media; they possibly represent a portion of recommended media - unculturables. © 2018 National Institute of Oceanography and Fisheries

Ali, S. M., G. Amin, M. Fayez, M. EL-Tahan, M. Monib, and N. A. Hegazi, "Production of rhizobia biofertilizers using baker's yeast effluent and their application to Leucaena leucocephala", Archives of Agronomy and Soil Science, vol. 51, issue 6, pp. 605 - 617, 2005. AbstractWebsite

Industrial baker's yeast effluent (BYE) was experimented on as a culture medium for growth and biomass production of six fast-growing rhizobia strains. Diluting the effluent with distilled water was necessary to maximize bacterial biomass production. The addition of phosphate buffer, ammonium chloride or trace-elements did not improve the final biomass yield of tested micro-organisms. Rhizobial growth and biomass on the effluent were comparable to traditional yeast extract mannitol medium (YEM). The Rhizobium spp. biomass, produced using either YEM or BYE, was evaluated as inoculum for Leucaena leucocephala (Lam.) de Wit in a pot experiment. No significant differences were reported in respect of legume nodule and growth parameters. Simultaneous inoculation with rhizobia and a group of associative diazotrophs supported better nodulation and nitrogenase activity. © 2005 Taylor & Francis.

Ali, S. M., M. A. Hamza, G. Amin, M. Fayez, M. EL-Tahan, M. Monib, and N. A. Hegazi, "Production of biofertilizers using baker's yeast effluent and their application to wheat and barley grown in north Sinai deserts", Archives of Agronomy and Soil Science, vol. 51, issue 6, pp. 589 - 604, 2005. AbstractWebsite

Effluent from the baker's yeast industry was experimented on as a culture medium for the growth and biomass production of diazotrophs. The effluent supported good growth of Azotobacter chroococcum, Enterobacter agglomerans and Klebsiella pneuomoniae, Azospirillum brasilense, Bacillus polymyxa and Pseudomonas putida and strongly proposed for biofertilizers production of associative diazotrophs. Slurry preparations containing natural polymers, e.g. Arabic gum (5%), pero-dextrin (20%), starch granules (10%) or gelatine (20%) were impregnated with cells of tested diazotrophs. With storage, entrapped cells of B. polymyxa were viable up to 160 days, while gradual decreases in Azospirillum numbers were recorded. Pero-dextrin, a by-product of the starch industry, was selected as the appropriate biocarrier accommodating diazotroph cells and maintaining prolonged survival rates and nitrogenase activity. Cell cultures of A. brasilense, A. chroococcum, B. polymyxa, E. agglomerans and P. putida were equally mixed and entrapped into pero-dextrin slurry biofertilizer formulation named as "BIOGRAMINA". Tested diazotrophs successfully survived (ca. 108 cfu ml-1) in such formulation up to 6 months at both ambient and cold temperatures. The response of wheat and barley to "BIOGRAMINA" in the presence or absence of N fertilizers was evaluated in greenhouse and field trials. Highest total biological yields were recorded for inoculated plants simultaneously supplemented with rational N fertilizer dose. © 2005 Taylor & Francis.

Ali, S. M., S. Z. Sabae, M. Fayez, M. Monib, and N. A. Hegazi, "The influence of agro-industrial effluents on River Nile pollution", Journal of Advanced Research, vol. 2, issue 1, pp. 85 - 95, 2011. AbstractWebsite

The major agro-industrial effluents of sugarcane and starch industries pose a serious threat to surface waters. Their disposal in the River Nile around Cairo city transitionally affected the microbial load. In situ bacterial enrichment (50-180%) was reported and gradually diminished downstream; the lateral not vertical effect of the effluent disposal was evident. Disposed effluents increased BOD and COD, and then progressively decreased downstream. Ammoniacal N was elevated, indicating active biological ammonification and in situ biodegradability of the effluents. In vitro, the nitrogen-fixing rhizobacteria Crysomonas luteola, Azospirillum spp., Azomonas spp. and K. pneumoniae successfully grew in batch cultures prepared from the crude effluents. This was supported by adequate growth parameters and organic matter decomposition. Therefore, such biodegradability of the tested agro-industrial effluents strongly recommends their use for microbial biomass necessary for the production of bio-preparates. © 2010.

Daanaa, H. - S. A., M. Abdou, H. A. Goda, M. T. Abbas, M. A. Hamza, M. S. Sarhan, H. H. Youssef, R. Hamed, M. EL-Tahan, M. Fayez, et al., "Plant pellets: A compatible vegan feedstock for preparation of plant-based culture media and production of value-added biomass of rhizobia", Sustainability (Switzerland), vol. 12, issue 20, pp. 1 - 19, 2020. AbstractWebsite

Although plant-based culture media enhances in vitro cultivation of rhizobacteria, studies assessing their biomass potential for large-scale applications are lacking. Here, we advance plant pellets (PPs) as a novel technology to unlock the potential of such vegan culture media for biomass production of Rhizobium leguminosarum. PP formulations were based on mixtures of Egyptian clover powder and the agro-byproducts glycerol and molasses. These mixtures were either contained or not contained in teabags during culture media preparation. Metrics of biomass included colony forming units, optical density (OD600nm), and cell dry weight (DW). Biomass comparisons between culture media based on PPs and standard yeast extract mannitol (YEM) revealed that the following PPs composition, contained in teabags, cultivated rhizobia at levels comparable to YEM: 16 g clover powder, 5% molasses, and 0.8% glycerol. This PPs composition enabled shorter generation times of rhizobia (PP: 3.83 h, YEM: 4.28 h). Strikingly, PPs mixtures supplemented with 10% molasses and not contained in teabags promoted rhizobia without apparent lag phases and produced 25% greater DW than YEM. PPs potentiate the use of dehydrated vegan feedstocks for both plant microbiota cultivation and biomass production and appear as cost-and labor-effective tools, easy to handle and store for plant-based culture media preparation. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.

El-Zanfaly, H. T., I. Hosny, M. Fayez, and A. Shaban, "Sanitary significance of fecal streptococci in underground water in Egypt.", Zentralblatt für Mikrobiologie, vol. 144, issue 5, pp. 299 - 304, 1989. AbstractWebsite

Underground water samples taken from 15 wells located at 3 municipal water works in Cairo were examined for the presence of fecal streptococci as a fecal pollution indicator. Fecal streptococci were detected in 96.4% of the 111 representative samples. Ranges of such pollution indicator were 1-17, 1-17 and 1-24 MPN/100 ml for water samples collected from wells in Mustorod, El-Marg and El-Maadi water works, respectively. A total of 200 pure strains of streptococci were isolated and subjected to biochemical and serological tests. Biochemical tests showed that only 26 strains could be classified as related to group D streptococci (enterococcus). Fore further identification, serological test was applied using 48 isolates chosen at random. The distribution of isolates among various serological groups showed that only 15 isolates (31%) could be classified into 5 defined groups (A, B, C, F and G). On the other hand, 4 isolates could not be defined serologically. The remaining 29 isolates (60%) gave a mixed reaction.

El-Zanfaly, H. T., I. Hosny, M. Fayez, and A. M. Shaban, "Incidence of antibiotic resistant bacteria in underground water", Environment International, vol. 14, issue 5, pp. 391 - 394, 1988. AbstractWebsite

Bacteria other than fecal coliform were isolated from the negative Eijkman test tubes by streaking on eosin methylene blue agar plates. A total of 101 isolates from underground water pumped from three water works in Cairo were classified into genera or groups according to their morphological, cultural and physiological characters and tested for their resistance towards four commonly used antibiotics namely chloramphenicol, tetracycline, neomycin, penicillin and one chemotherapeutic agent namely 2-sulfanilamide pyrimidine. Results showed that 77 and 64 isolates were resistant to penicillin and 2-sulfanilamide pyrimidine and in addition, 32 isolates were resistant to tetracycline. Only 18 and 8 isolates were resistant to chloramphenicol and neomycin, respectively. It was also found that 19 isolates belonging to 6 genera or groups were sensitive towards all of the tested compounds. © 1989.

Elsawey, H., S. Patz, R. A. Nemr, M. S. Sarhan, M. A. Hamza, H. H. Youssef, M. R. Abdelfadeel, H. - S. A. Daanaa, M. EL-Tahan, M. Abbas, et al., "Plant broth-(Not bovine-) based culture media provide the most compatible vegan nutrition for in vitro culturing and in situ probing of plant microbiota", Diversity, vol. 12, issue 11, pp. 1 - 19, 2020. AbstractWebsite

Plant microbiota support the diversity and productivity of plants. Thus, cultivation-dependent approaches are indispensable for in vitro manipulation of hub taxa. Despite recent advances in high-throughput methods, cultivability is lagging behind other environmental microbiomes, notably the human microbiome. As a plant-based culturing strategy, we developed culture media based on a broth of cooked aqueous mixtures of host plants. This improved the in vitro growth of representative isolates of plant microbiota and extended the in situ recovery of plant microbiota. With clover, 16S rRNA gene sequencing of representative isolates confirmed the predominance of Firmicutes, Alphaproteobacteria and Gammaproteobacteria, and less frequently Bacteroidetes and Actinobacteria. Whereas bovine-based culture media (modified R2A) confined the diversity to Firmicutes, the plant broth-based culture media revealed a wider scope of endophytes beyond rhizobia, i.e., multiple genera such as Chryseobacterium, Cronobacter, Kosakonia, Tsukamurella, and a potentially/presumptive novel species. Matrix-assisted laser desorption/ionization time-of-flight (MADI-TOF) analysis clustered isolates according to their plant niches, the endo-phyllosphere/endo-rhizosphere. We recommend the plant broth for simplicity, reproducibility and perdurable storage, supporting future culturomics applications, good laboratory practice (GLP) and good manufacturing practice (GMP). The strategy creates an “in-situ-similis” vegan nutritional matrix to analyze microbial diversity and reveal novel microbial resources pertinent to biotechnological and environmental applications. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.

Fayez, M., N. F. Emam, and H. E. Makboul, "Interaction of the herbicides Bromoxynil and Afalon S with Azospirillum and growth of maize", Zeitschrift für Pflanzenernährung und Bodenkunde, vol. 146, issue 6, pp. 741 - 751, 1983. AbstractWebsite

The possible interaction of herbicides Bromoxynil and Afalon S with Azospirillumspp. and growth of maize was investigated in a greenhouse experiment. Neither inoculation nor herbicide application with or without inoculation had significant effect on the major groups of soil microflora (bacteria, actinomycetes, and fungi). The highest values of nitrogenase as well as dehydrogenase activity were recorded in treatment received only Azospirillum. Incorporation in soil of either Bromoxynil or Afalon S at the recommended field dose seemed to have no significant effect on the enzymatic activities, while application of these herbicides with Azospirillum had stimulatory effects in some cases. The application of either Bromoxynil or Afalon S significantly increased the dry weight of roots and shoots at 45 days period. The effect of herbicide on plant growth was more pronounced when applied with Azospirillum and the highest stimulatory effect was observed when Afalon S was applied with the N2‐fixing microorganism. Copyright © 1983 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim

Fayez, M., and Z. Y. Daw, "Effect of inoculation with different strains of Azospirillum brasilense on cotton (Gossipium barbadense)", Biology and Fertility of Soils, vol. 4, issue 1-2, pp. 91 - 95, 1987. AbstractWebsite

The response of the cotton plant to inoculation with six strains of Azospirillum brasilense was investigated under subtropical conditions in Egypt. Azospirilla populations and activities were increased as a result of root inoculation with liquid inoculum of Azospirillum sp. Highest C2H2 - reduction activities on roots were obtained with strains S631 and Sp Br 14 (means of 216.85 and 209.50 nmol C2H4g-1 root h-1 respectively) while strain M4 gave the lowest activity (mean of 100.8 nmol C2H4g-1 root h-1). Statistical analysis showed that Azospirillum strains 5631, Sp Br 14, E15 and SC22 significantly increased the plant dry weight and nitrogen uptake while inoculation with strains M4 and SE had no significant effect in that respect. © 1987 Springer-verlag.

Fayez, M., "Bacterial composition and N2‐fixation of some Egyptian soils cultivated with wheat (Triticum aestivum L.)", Zeitschrift für Pflanzenernährung und Bodenkunde, vol. 152, issue 4, pp. 385 - 389, 1989. AbstractWebsite

The composition of the microflora, N2‐fixing bacteria particularly, in different soils cultivated with wheat in Egypt was investigated in some samples collected from the fields after applying the agricultural practices recommended for wheat cultivation and just before sowing. The influence of carbon sources, mineral nitrogen and water regimes on potential dinitrogen fixation (acetylene reduction assay) in soils was investigated. The bacterial population densities including‐N2‐fixing organisms were related to a number of environmental factors such as organic matter content. Among diazotrophs, Azotobacter spp. and Azospirillum spp. were encountered in higher densities in comparison with clostridia. Unamended soils showed a lower acetylene‐reducing activity (0.5–61.5 nmoles C2H4 g−1 h−1). Addition of glucose (1% w/w) greatly enhanced such activity being the highest (86.9–2846.5 nmoles C2H4 g−1 h−1) in the clay soil with the highest organic carbon content (1.42%). Glucose amendment had no significant influence on acetylene reduction in the saline soil. N2‐fixation in barley straw‐amended (1%) soils was not much higher than in unamended soils. Concentrations of up to 70 ppm ammonium‐nitrogen depressed N2‐fixation in soils that received barley straw. Acetylene reduction in submerged soil increased after addition of cellulose. Non‐flooded conditions favoured N2‐fixation in the fertile clay soil amended with sucrose. Copyright © 1989 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim

Fayez, M., "Untraditional N2-fixing bacteria as biofertilizers for wheat and barley", Folia Microbiologica, vol. 35, issue 3, pp. 218 - 226, 1990. AbstractWebsite

The screening of 27 isolates grown on nitrogen-free medium for nitrogen-fixing ability resulted in the isolation of five organisms belonging to Bacillaceae, Enterobacteriaceae and Pseudomonadaceae. Estimates of N2-fixation efficiencies of these isolates indicated that they may be responsible for low rates of N2-fixation in soil. The possible association of these isolates as well as of Azotobacter and Azospirillum with wheat and barley was investigated in a greenhouse experiment. The highest values of nitrogenase activity on plant root were recorded in treatments inoculated with composite inocula of the isolated N2-fixers, particularly when Azotobacter and/or Azospirillum were added in combination. Inoculation with single inoculum of each of the N2-fixing isolates had no significant influence on plant growth, except with Pseudomonas and Bacillus for wheat and barley, respectively. Highly significant increases in growth of both plants were recorded in all cases of multistrain inoculation. © 1990 ACADEMIA, Publishing House of the Czechoslovak Academy of Sciences.

Fayez, M., S. H. Shehata Heba, G. A. El-Morsy, A. Rahal, and A. F. Shahaby, "Complement of integrated fertilizer management and integrated pest management concepts to ameliorate faba bean growth and yield", Archives of Agronomy and Soil Science, vol. 50, issue 4-5, pp. 397 - 419, 2004. AbstractWebsite

Twenty-one microbial preparations recommended for controlling pathogenic fungal strains causing root rot and wilt diseases of faba bean were investigated for antibiosis against several symbiotic and associative diazotrophs adopting a modified agar-plate-inhibition-zone assay. Rhizobium and Bradyrhizobium exhibited a somewhat similar susceptibility to biocontrol agents while associative diazotrophs showed variable responses. Azotobacter, compared to others, was severely inhibited by such bio-candidates. The members of the biofertilizer formulation ‘Biofertan’ did bear mixed cultivation with the majority of biocontrol agents. Among those, Bacillus subtilis was deemed the pioneer. In pot experiments, almost all the antagonists significantly restricted the severity of root rot and wilt diseases besides modifying faba bean seedling stand and improving plant development. This was very obvious with shoot biomass increases of >50%. Moreover, the bioagents successfully recovered the legume establishment, seriously injured due to pathogenic fungal infection. Simultaneous inoculation with Rhizobium and biocontrol agents provided more growth stimulation compared to either when introduced individually. Field-grown faba beans were inoculated with the diazotroph and representatives of biocontrol strains by two different methods, seed coating and over-head soil. Growth parameters determined were the highest when the legume plant was seed-coated by Rhizobium simultaneously over-head soil inoculated with the bacterial bioagents; this was reported with Bacillus subtilis and Pseudomonas aerugenosa. The significance of combined application of biofertilizer and bioagent to ensure cheap, clean and safe farm products is discussed. © 2004 Taylor & Francis Ltd.

Fayez, M., and R. R. Shahin, "Effects of industrial liquid wastes on dinitrogen fixation and microflora of soils and waters", Zeitschrift für Pflanzenernährung und Bodenkunde, vol. 150, issue 4, pp. 220 - 227, 1987. AbstractWebsite

Potential N2‐fixation was investigated in a number of samples representing soils and water courses under the effect of some industrial wastes in Helwan area of Egypt. Microbiological analysis of soil and water samples showed the general enrichment of fungi, actinomycetes and bacteria including N2‐fixers. Among asymbiotic N2‐fixers, azospirilla compared to azotobacters and clostridia were found to be present with rather higher densities in all samples tested. Generally, the microbial numbers increased by increasing the distance from the Industrial Complex at Helwan, which could be attributed to the high levels of salinity and total heavy metals near the factories. The results indicated that the industrial wastes near the factories exerted inhibitory effects on the acetylenereducing activity in soils, which seriously reduces their biological fertility. Such effects were decreased by getting away from the factories. Significantly negative correlations were recorded between densities of N2‐fixers or N2‐ase activity and salinity and total heavy metals content in both soil and water samples. Copyright © 1987 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim

Fayez, M., "Interactions of some nematicides with Azospirillum lipoferum and the growth of Zea maize", Zeitschrift für Pflanzenernährung und Bodenkunde, vol. 153, issue 4, pp. 219 - 223, 1990. AbstractWebsite

The possible interaction of four nematicides (Terbufos, Carbofuran, Fenamiphos, and Aldicarb) with Azospirillum lipoferum and growth of two Zea maize cultivars was studied in a greenhouse experiment. Application of nematicides, Fenamiphos in particular, resulted in higher plant length, dry matter production and N yield over the nematicide‐untreated plants. Azospirillum spp. inoculation stimulated the growth of nematicide‐treated Z. maize. Among the nematicides used, Carbofuran and Aldicarb inhibited the nitrogenase activity on plant roots more seriously than Fenamiphos and Terbufos. Generally, the inhibition percentages in acetylene reducing activity in soil of inoculated treatments were lower (14.4 ‐ 61.8%) than those reported for the uninoculated ones (21.4 ‐ 73.9%). Soil, irrespective of treatment, regained a part of its normal N2‐ase activity with time. Field concentrations of all nematicides showed different inhibitory effects on N2‐ase activity of Azospirillum spp. in culture medium, such effects increased with increased doses (10‐ and 100‐ fold) and incubation periods (10 days). The contribution of Azospirillum spp. to the N economy of soil treated with nematicides is discussed. Copyright © 1990 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim

Fayez, M., and Z. Y. Daw, "Growth and acetylene reducing activity of azospirilla as affected by interaction with soil streptomyces, penicillia and fusaria", Soil Biology and Biochemistry, vol. 22, issue 8, pp. 1143 - 1149, 1990. AbstractWebsite

A total of 68 actinomycete and 63 fungal isolates obtained from various soils were tested for their ability to antagonize different strains of Azospirillum in sterile soil. It was found that between 78 and 87% of the streptomycete and between 75 and 83% of the fungal isolates respectively did not inhibit azospirilla. Numbers of azospirilla in soil were seriously reduced when they interacted with some of the streptomycete and fungal isolates. In soil treated with both azospirilla and either streptomycetes or fungi, the nitrogenase activity ranged from ca 2-210 nmol C2H4g-1h-1. In general, the acetylene reducing activity (ARA) in soils treated with fungi was reduced more seriously than those treated with streptomycetes; the mean ARA reported in the presence of fungi was 23 nmol C2H4g-1 h-1 against 48 in the presence of streptomycetes. The reduction in both azospirilla number and ARA in soil may have reflected the increasing population of antagonists. Highly-significant negative correlations between the diameter of inhibition zones produced by the active Streptomyces and fungal isolates using the agar-disc method were found with both numbers and ARA of most Azospirillum strains in soil. © 1990.

Hanna, A. L., H. H. Youssef, W. M. Amer, M. Monib, M. Fayez, and N. A. Hegazi, "Diversity of bacteria nesting the plant cover of north Sinai deserts, Egypt", Journal of Advanced Research, vol. 4, issue 1, pp. 13 - 26, 2013. AbstractWebsite

North Sinai deserts were surveyed for the predominant plant cover and for the culturable bacteria nesting their roots and shoots. Among 43 plant species reported, 13 are perennial (e.g. Fagonia spp., Pancratium spp.) and 30 annuals (e.g. Bromus spp., Erodium spp.). Eleven species possessed rhizo-sheath, e.g. Cyperus capitatus, Panicum turgidum and Trisetaria koelerioides. Microbiological analyses demonstrated: the great diversity and richness of associated culturable bacteria, in particular nitrogen-fixing bacteria (diazotrophs); the majority of bacterial residents were of true and/or putative diazotrophic nature; the bacterial populations followed an increasing density gradient towards the root surfaces; sizeable populations were able to reside inside the root (endorhizosphere) and shoot (endophyllosphere) tissues. Three hundred bacterial isolates were secured from studied spheres. The majority of nitrogen-fixing bacilli isolates belonged to Bacillus megaterium, Bacillus pumilus, Bacillus polymexa, Bacillus macerans, Bacillus circulans and Bacillus licheniformis. The family Enterobacteriaceae represented by Enterobacter agglomerans, Enterobacter sackazakii, Enterobacter cloacae, Serratia adorifera, Serratia liquefaciens and Klebsiella oxytoca. The non-Enterobacteriaceae population was rich in Pantoae spp., Agrobacterium rdiobacter, Pseudomonas vesicularis, Pseudomonas putida, Stenotrophomonas maltophilia, Ochrobactrum anthropi, Sphingomonas paucimobilis and Chrysemonas luteola. Gluconacetobacter diazotrophicus were reported inside root and shoot tissues of a number of tested plants. The dense bacterial populations reported speak well to the very possible significant role played by the endophytic bacterial populations in the survival, in respect of nutrition and health, of existing plants. Such groups of diazotrophs are good candidates, as bio-preparates, to support the growth of future field crops grown in deserts of north Sinai and irrigated by the water of El-Salam canal. © 2011 .

Hegazi, N. A., M. S. Sarhan, M. Fayez, S. Patz, B. R. Murphy, and S. Ruppel, "Plant-fed versus chemicals-fed rhizobacteria of Lucerne: Plant-only teabags culture media not only increase culturability of rhizobacteria but also recover a previously uncultured Lysobacter sp., Novosphingobium sp. and Pedobacter sp.", PLoS ONE, vol. 12, issue 7, 2017. AbstractWebsite

In an effort to axenically culture the previously uncultivable populations of the rhizobacteria of Lucerne (Medicago sativa L.), we propose plant-only teabags culture media to mimic the nutritional matrix available in the rhizosphere. Here, we show that culture media prepared from Lucerne powder teabags substantially increased the cultivability of Lucerne rhizobacteria compared with a standard nutrient agar, where we found that the cultivable populations significantly increased by up to 60% of the total bacterial numbers as estimated by Quantitative Real-time Polymerase Chain Reaction (qRT-PCR). Cluster analysis of 16S rDNA Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis (PCR-DGGE) of cultivable Colony-Forming Units (CFUs) revealed a more distinct composition and separation of bacterial populations recovered on the plant-only teabags culture media than those developed on a standard nutrient agar. Further, the new plant medium gave preference to the micro-symbiont Sinorhizobium meliloti, and succeeded in isolating a number of not-yet-cultured bacteria, most closely matched to Novosphingobium sp., Lysobacter sp. and Pedobacter sp. The present study may encourage other researchers to consider moving from the well-established standard culture media to the challenging new plant-only culture media. Such a move may reveal previously hidden members of rhizobacteria, and help to further explore their potential environmental impacts. © 2017 Hegazi et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Hegazi, N. A., M. S. Sarhan, M. Fayez, S. Patz, B. R. Murphy, and S. Ruppel, Plant-fed versus chemicals-fed rhizobacteria of Lucerne: Plant-only teabags culture media not only increase culturability of rhizobacteria but also recover a previously uncultured Lysobacter sp., Novosphingobium sp. and Pedobacter sp., , vol. 12, issue 7: Public Library of Science San Francisco, CA USA, pp. e0180424, 2017. Abstract
Hegazi, N. A., and M. Fayez, "Biological nitrogen fixation to maximize productivity of intercropped legumes and non-legumes: Ten years of field experimentations in semi-arid deserts of Egypt", Archives of Agronomy and Soil Science, vol. 47, issue 1-2, pp. 103 - 131, 2001. AbstractWebsite

A number of field trials was executed in semi-arid deserts of Ismailia, Egypt, to experiment growth and productivity of sole or mixed canopies of legumes (soybean, leucaena, sesbania, berseem and grasspea) and non-legumes (corn, Rhodes grass, elephant grass, ryegrass and barley) when inoculated with N 2 -fixing bacteria (diazotrophs) in presence or absence of N fertilizers. An average estimate of > 20 Kg N acre −1 was transferred to neighbouring unfertilized corn, and land equivalent ratio (LER) reached 1.35. Rhodes grass mixed with sesbania or leucaena produced higher biomass yield compared to pure N-fertilized stands; increases of 66–91% and 22–29% were reported for inoculated and non-inoculated plants respectively. In mixed canopy with berseem, dry matter yield of the non-legume partner increased compared to that in pure stands, being higher for barley (120–255%) compared to ryegrass (62–115%). Similar trends were scored with N yield. Response of elephant grass to inoculation with associative diazotrophs was more pronounced when intercropped with leucaena as increases over pure stand in dry matter production approximated 40%. On the other hand, both grasspea and barley were negatively affected by intercropping. Total biomass and N-yields of barley were more affected than grasspea. © 2001 Taylor & Francis Group, LLC.

Hegazi, N. A., and M. Fayez, "Biodiversity and endophytic nature of diazotrophs other than rhizobia associated to non-leguminous plants of semi-arid environments", Archives of Agronomy and Soil Science, vol. 49, issue 2, pp. 213 - 235, 2003. AbstractWebsite
Kandil, H. B. A., M. F. M. Abdelall, E. A. Tantawy, M. A. Ali, and M. Fayez, "Plant growth promoting merits of some endophytic bacteria to support growth of wheat in salt affected soil", Bioscience Research, vol. 15, issue 1, pp. 102 - 109, 2018. AbstractWebsite

This study was planned to examine the contribution of the plant growth promoting Rhizobium leguminosarum biovar vicea (ICARDA 441) along with five strains of endophytic bacteria isolated from saline soil to support growth of salt affected wheat plants. Phylogentic analysis based on the 16S rDNA sequences belonged these endophytes to Pantoea agglomernas HP2-MG738254, Pseudomonas stutzeri H1-MG738255, Klebsiella sp. H3-MG738256, Brevundimonas diminuta H4-MG738257 and Bacillus cereus H5- MG738258. In a field trial, inocula of these endophytes supported wheat plant growth in salt affected soil. The obtained results refer to improved germination, increases in dry weight, grain yield and protein concentration scored (2 g plant-1, 3799 Kg ha-1, 9.9%) respectively compared with control and increased nutrient uptake by wheat as a result of inoculation with the examined strains. © 2017 author (s).