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The main problems of sandy soil are its inability to hold on to nutrients, its fast drainage, its lack of soil structure and its small buffering capacity. It cannot hold on to nutrients because it has little or no clay and organic matter. Therefore, the objective of this study was to determine the effect of the combined application of some synthetic soil conditioners with two forms of humic acids (HA) as organic soil conditioners in reducing nitrogen fertilizer requirements to maximize wheat yield productivity. So, two experiments were designed in a split-split plot design with three replicates at the Experimental Station Farm in El-Ismailia governorate during the two successive winter seasons using wheat plant (Triticum Sativacv Giza 168). The treatments included two forms of organic acids and synthetic soil conditioners in the presence of three levels of nitrogen fertilizer. The common agricultural practices for growing wheat according to the recommendations of the Ministry of Agriculture were followed. Obtained results revealed that the application of humic acids type either HK or HCa in combination with PVA or bitumen emulsion under different application rates of nitrogen fertilizers enhanced wheat plant productivity (yield, straw, and grains kg/fed) along with uptake macronutrient as compared to control treatment. The superior one was HCa in combination with PVA and B in presence of 75% N application in the first and second season, respectively. Moreover, soil fertility was improved by adding soil conditioners in different forms with/without nitrogen fertilizers as compared to the control treatment i.e. EC values, OM, and available NPK were significantly increased in all treatments applied; the maximum increase was observed with HCa combination with B at 75% from nitrogen dose. Also, the same trend was observed with dry stable aggregates and total porosity of sandy soil for an average of two seasons. An opposite trend was observed with bulk density whose values generally decreased with all treatments. In conclusion, can be clarified that the application of humic materials either HK or HCa was increasing soil fertility which is reflected in wheat plant productivity but it was more efficient when in combination with synthetic polymers especially B, and can save about 25% from nitrogen fertilizer applied.

Capturing the diverse microbiota from healthy and/or stress resilient plants for further preservation and transfer to unproductive and pathogen overloaded soils, might be a tool to restore disturbed plant–microbe interactions. Here, we introduce Aswan Pink Clay as a low-cost technology for capturing and storing the living root microbiota. Clay chips were incorporated into the growth milieu of barley plants and developed under gnotobiotic conditions, to capture and host the rhizospheric microbiota. Afterward, it was tested by both a culture-independent (16S rRNA gene metabarcoding) and -dependent approach. Both methods revealed no significant differences between roots and adjacent clay chips in regard total abundance and structure of the present microbiota. Clay shaped as beads adequately supported the long-term preservation of viable pure isolates of typical rhizospheric microbes, i.e. Bacillus circulans, Klebsiella oxytoca, Sinorhizobium meliloti, and Saccharomyces sp., up to 11 months stored at −20°C, 4°C, and ambient temperature. The used clay chips and beads have the capacity to capture the root microbiota and to long-term preserve pure isolates. Hence, the developed approach is qualified to build on it a comprehensive strategy to transfer and store complex and living environmental microbiota of rhizosphere toward biotechnological application in sustainable plant production and environmental rehabilitation.

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.