Characterization and identification of nitrogen fixing cyanobacteria in Egyptian sandy and alluvial (clay loam) soils [electronic resource].

Includes reference

Samples of two different soils were collected from the surface layer (0- 30 cm) of El- lsmailia Research Station (sandy soil) (El- lsmailia Governorate) (30°35' 41.901" N, 32"16'45.834" E) and Sids Res. Farm (alluvial clay loam soil) (Beni Swef Governorate) (29" 4' 54.349" N, 31° 5' 25. 775" E), Agric. Res. Center, Giza Egypt, to isolate the prevailing cyanobacterial inhabitants. Characterization of the cyanobacterial biomass production and nitrogen fixing efficiency (nitrogenase activity) along 5 weeks incubation periods were also tested. Results revealed that, the six isolated cyanobacterial strains identified as Nostoc muscorum, Nostoc commune, Nostoc linckia, Nostoc ellipsosporum, Anabaena variabilis and Anabaena orientalis, and found to be commonly filamentous heterocystous nitrogen fixing agents. Nostoc muscorum recorded the highest biomass, followed by Anabaena variabilis, Anabaena orientalis. Nostoc linckia, Nostoc ellipsosporum and Nostoc commune. While, for nitrogenase activity, N. muscorum and A. variabilis gave the highest values against the others namely N. commune and N. linckia. Some of those cy§lnobacterial strains, i.e., N. muscorum and A. variabilis can be a promise to support and improve the fertility of soil, due to their high efficiency to fix the atmospheric nitrogen when inoculating the cropped soils.

Summary in arabic.

1