- Guttation
Guttation is the appearance of drops of
xylem sap on the tips or edges of leaves of somevascular plant s, such asgrass es.At night,
transpiration usually does not occur because most plants have theirstomata closed. When there is a highsoil moisture level, water will enter plant roots, because thewater potential of the roots is lower than in the soil solution. The water will accumulate in the plant creating a slightroot pressure . The root pressure forces some water to exude through specialleaf tip or edge structures,hydathode s, forming drops. Root pressure provides the impetus for this flow, rather thantranspirational pull .Guttation fluid may contain a variety of organic compounds, mainly sugars, and mineral nutrients, and potassium. [cite journal | last = Goatley | first = James L. | authorlink = | coauthors = Lewis, Ralph W. | title = Composition of Guttation Fluid from Rye, Wheat, and Barley Seedlings | journal = Plant Physiology | volume = 41 | issue = 3 | pages = 373–375 | publisher = | date = March 1966 | url = http://www.pubmedcentral.gov/articlerender.fcgi?tool=pmcentrez&artid=1086351 | doi = | id = | accessdate = 2006-10-31 | pmid = 16656266] On drying, a white crust remains on the leaf surface.
If high levels of nitrogen appear in the fluid, then that is a sign of
fertilizer burn . Excess nitrogen must be leached from the soil by addition of large quantities of water. This may result inwater pollution , but is the best way to restoresoil fertility . [ [http://www.improve-your-garden-soil.com/fertilizer-burn.html Avoiding Fertilizer Burn ] ]Guttation is not to be confused with
dew , which condenses from the atmosphere onto the plant surface.ee also
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Soil plant atmosphere continuum References
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