ISSN:
1573-5036
Keywords:
Acetylene reduction
;
Inoculation
;
Klebsiella oxytoca
;
Nitrogen fixation
;
Wheat
Source:
Springer Online Journal Archives 1860-2000
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Summary Of 45 fermentative gram negative bacterial isolates examined from wheat roots, three were capable of fixing atmospheric nitrogen as determined by the acetylene reduction technique and by protein contents of cells. A gram negative non-motile facultatively anaerobic bacterial strain capable of N2 fixation was identified asKlebsiella oxytoca ZMK-2. Optimal growth and N2 fixation occurred at pH 6.5. The optimum temperatures for growth under anaerobic conditions ranged between 30°–37°C. Acetylene reduction by intact cells was strikingly inhibited by 0.1 atm. or greater partial pressure of O2. Furthermore, the accumulation of H2 in the gas phase over cultures ofKlebsiella oxytoca ZMK-2 at partial pressures greater than 0.02 atm. resulted in a striking inhibition in the rate of C2H2 reduction. The addition of suspensions of eitherKlebsiella oxytoca ZMK-2 orAzotobacter vinelandii or a mixed culture of these two organisms to axenic cultures of wheat plants produced no significant increase in plant growth as measured by plant dry weight or nitrogen content of plants.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02277362
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