ISSN:
1432-2048
Keywords:
Nitrate/nitrite assimilation
;
Nitrogen metabolism (dark O2, dark N2)
;
Zea (nitrogen metabolism, leaf)
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract The assimilation of nitrate under dark-N2 and dark-O2 conditions in Zea mays leaf tissue was investigated using colourimetric and 15N techniques for the determination of organic and inorganic nitrogen. Studies using 15N indicated that nitrate was assimilated under dark conditions. However, the rate of nitrate assimilation in the dark was only 28% of the rate under non-saturating light conditions. No nitrite accumulated under dark aerobiosis, even though nitrate reduction occurred under these conditions. The pattern of nitrite accumulation in leaf tissue in response to dark-N2 conditions consisted of three phases: an initial lag phase, followed by a period of rapid nitrite accumulation and finally a phase during which the rate of nitrite accumulation declined. After a 1-h period of dark-anaerobiosis, both nitrate reduction and nitrite accumulation declined considerably. However, when O2 was supplied, nitrate reduction was stimulated and the accumulated nitrite was rapidly reduced. Anaerobic conditions stimulated nitrate reduction in leaf tissue after a period of dark-aerobic pretreatment.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00392129
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