ISSN:
1573-5036
Keywords:
Cotton Nitrate
;
Nitrate reductase
;
Nitrogen Waterlogging
;
Xylem exudate
Source:
Springer Online Journal Archives 1860-2000
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Summary Cotton is reported to be susceptible to waterlogging, and there is evidence that some of the symptoms shown by waterlogged plants are due to impaired uptake of nitrogen. To investigate this for cotton, the nitrogen nutrition of a field-grown crop was monitored when the plants were subjected to two short term periods of waterlogging of varying severity using a sloping plot water-table facility. Growth of severely waterlogged cotton decreased after 4 days in the first and second floodings, and these plants were wilted by the end of the first flooding but not the second. Waterlogging resulted in decreased concentrations of total-N and especially NO 3 − −N in the petiole and lamina of the youngest fully-expanded leaf. Uptake of N by waterlogged plants occurred, but was not as great as for well-aerated plants. The nitrate reductase activity of leaves was much lower in waterlogged plants. Stumps of detopped waterlogged plants did not exude sylem sap at the end of the first flooding, suggesting impaired solute uptake due to damaged roots. However, xylem exudate was obtained from stumps of waterlogged plants at the end of the second flooding, indicating adaptive changes to the root systems of these plants. Although cotton is reported to reduce little NO 3 − −N in its roots, analysis of xylem exudate showed that about half of the N exported by roots was as amino compounds. The concentration of amino compounds in xylem exudate from severely waterlogged plants was higher than in well-aerated plants. It was concluded that the growth reduction in waterlogged cotton was due partly to induced N-deficiency.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02181905
Permalink
