Sa. Kabli et al., EFFICIENCY OF CYANOBACTERIA FROM SOIL OF WESTERN REGION IN THE KINGDOM OF SAUDI-ARABIA AS BIOFERTILIZER FOR WHEAT, Arab Gulf journal of scientific research, 15(2), 1997, pp. 481-503
Nine species of cyanobacteria were isolated from agricultural soil of
Western region in the Kingdom of Saudi Arabia. Except for Phormidium s
p, and Oscillatoria sp., all the isolated species were able to fix atm
ospheric nitrogen. The seven nitrogen fixing species exhibited differe
nt potentialities for atmospheric nitrogen fixation. The descending or
der for their potencies was as follows: Anabaena cylindrica; Anabaena
sp.; Gloeocapsa sp.; Synechococcus sp.; Chroococcus sp.; Lyngbya sp.;
Nostoc commune. It was also found that there was a correlation between
the efficiencies of cyanobacteria species for atmospheric nitrogen fi
xation and their biological activities. Results obtained revealed the
biomass of some cyanobacteria species to have stimulatory effect on th
e rate of respiration of cyanobacteria and other soil microbes, while
the biomass of other cyanobacteria species had inhibitory effect. Upon
tl:sting efficiency of these atmospheric nitrogen fixers in fulfillin
g the requirements of wheat plant for nitrogen, in the absence of this
element in the growth medium, it was found that Nostoc commune :and A
nabaena cylindrica could supply wheat plant with atmospheric nitrogen
to maintain its vegetative growth. Therefore, these species: of cyanob
acteria could be used as biofertilizers instead of utilizing expensive
industrial chemical manures.