Two successful field experiments were carried out during 2020and 2021 growing seasons to evaluate the effect of bio fertilizers; Bacillus amyloliquifaciens (BA), Bacillus megaterium (BM) and cyanobacteria inoculation on the vegetative growth, growth parameters and plant chemical content of Cucurbita pepo (Squash) crop. The study of mixed inoculation with both Bacillus strains, and cyanobacteria was found to improve vegetative growth, plant chemical contents and positive microbial activity in the soil Rhizosphere in comparison to un-inoculated plants. Soil available nutrients (N and K) increased significantly with BA and BM combined with cyanobacteria while available phosphorus gave most increase with BM.

During the summer growing seasons of 2021 and 2022, two field experiments were conducted at Ismailia Agricultural Research Center Station(Latitude 30ᵒ 35′ 41.901″ N and Longitude 32ᵒ 16′ 45. 843″E) to study the effect of cyanobacterial inoculation (Anabaena oryzae (A. oryzae) and Nostoc mascarum (N. mascarum)) on peanut yield, quality and certain soil biological activities under various nitrogen fertilization conditions and three types of applications, thefirst treatment was carried out as coating seeds with powder of individual of each cyanobacterial strain and the before planted, second treatment seeds were drenched withsuspension of eachcyanobacterial strain individually andthe last treatment was by foliar doses after 15, 45 and 60 days from seeds planting. Results showed that applying cyanobacteria inoculation to peanut plants generally enhanced peanut plant growth, leading to significantly higher yields of peanut and grains than uninoculated treatments. Treatment of N. mascarum + 75% N recorded the highest peanut yield and plant characteristics followed by N. mascarum+ 75% N in soil drench application compared to other tested treatments and types of applications. Cyanobacteria enhanced the amount of N, P, Kand Ca in peanut plants overall. By increasing the total chlorophyl, carotenoids, dehydrogenase, urease activities and nutrients in the peanut rhizosphere, cyanobacteria inoculation had a favorable impact on soil fertility. In general, cyanobacteria inoculation with 75% nitrogen amounts can benefit under peanut growth in sandy soil conditions.

The characteristics of two cyanobacterial strains, Anabaena oryzae and Nostoc muscorum, were studied in order to use them as biofertilizers in a field experiment conducted in the two winter seasons of 2021 and 2022 at the Ismailia Agricultural Research Center Station to study the effect of both strains on peanut plant in sandy soil. Cyanobacterial strains were used individually by coating seed, soil drench, and foliar applications, as well as mixed applications of two strains in various ways. Both cyanobacterial strains morphological examination revealed that they both have heterocysts, nitrogen, phosphorus, and potassium in their culture filtrate, and they were able to produce chlorophyll a and phosphatase enzymes. The results of an agricultural experiment showed that using Nostoc muscorum and Anabaena oryzae separately had a positive effect on peanut plants in a variety of applications, but combining both of these applications with 75% nitrogen increased the growth traits, nutrient contents, and soil biological activities in both peanut plants and their rhizosphere soil. The soil drench treatment with A. oryzae and Nostoc muscorum plus 75% nitrogen produced the highest growth results and peanut yields in a single application. The A. oryzae Soil Drench Application (S) + N. muscorum Foliar Application (F) with 75% N reported the best outcomes in mixed treatments. However, compared to single applications, all blended applications displayed better growth and yield characteristics. The results of the study suggest that employing cyanobacteria in a mixed application will enhance its advantages over a single use.

Three cyanobacterial filamentous, heterocystous isolates (A, B, and C) were isolated from sandy soil collected from the Ismailia Agricultural Research Station (ARC), Ismailia Governorate, Egypt. A polygenic approach was used to characterize these isolates, which included morphology, ultrastructure, and molecular analyses. The morphological analyses for the three strains agree with the molecular data (16S, ITS, and 23S rRNA sequences and phylogeny); the order of our isolates is: Nostocales and family: Nostocaceae, they identified as the following: isolate A: Trichormus variabilis; isolate C: Trichormus sp.) which are filamentous and terminal heterocysts; and isolate B: Nostoc sp.) colonies formed of filamentous heterocysts enclosed in a membrane and gelatinous polysaccharide sheath. Dry weight, pigment content, phytohormones, total nitrogen, total protein, exopolysaccharides, and phosphate dissolving were determined for three strains. The results showed that Trichormus variabilis has the highest chlorophyll a content, Nostoc sp. has the highest carotenoid content, and three strains have almost similar phycocyanin content, while three strains can secrete phytohormones and nitrogen in their medium and dissolve phosphate, with near values in Trichormus variabilis and Trichormus sp. and a slight difference in Nostoc sp. According to the findings of this study, cyanobacterial strains isolated from Ismailia Agricultural Research Station can be used as biofertilizers and nitrogen-fixing fertilizers because of their ability to secrete phytohormones and bioactive compounds and fix air nitrogen in free nitrogen medium.

Two field experiments were conducted at the Ismailia Agricultural Research Center Station during the summers of 2021 and 2022 to study the effects of cyanobacterial inoculation (Anabaena oryzae and Nostoc mascarum) on peanut plant growth, yield, and certain soil biological activities under different nitrogen fertilisation ratios and conditions. There are three applications: soil drenching, cyanobacterial seed coating, and foliar spray with cyanobacterial strains.The findings demonstrated that cyanobacteria inoculation of peanut plants generally improved peanut plant growth, resulting in significantly higher peanut and grain yields than uninoculated treatments. When compared to other tested treatments and types of applications, N. mascarum + 75% (N) produced the highest peanut yield and plant characteristics, followed by A. oryzae + 75% (N) in soil drench application. Overall, cyanobacteria increased the amount of N, P, K, and Ca in peanut plants. Cyanobacteria inoculation improved soil fertility by increasing total bacterial and cyanobacterial count (CO2) evolution, and indole acetic acid contents in the peanut rhizosphere. In general, peanut growth in sandy soil conditions can benefit from cyanobacteria inoculation with 75% nitrogen amounts.