Abstract
Roots of many weed and crop species contribute biologically active chemicals into the environment known as root exudates. Root exudates are known to influence growth and establishment of crop and weed species, and these are released from living root systems. Many perennial woody and herbaceous plants have deep and extensive root/rhizome subterranean systems, which can produce prolific amounts of root exudates over long periods of time. Root exudates contribute many types of organic compounds to the rhizosphere. In addition to simple and complex sugars and growth regulators, root exudates contain different classes of primary and secondary compounds including amino acids, organic acids, phenolic acids, flavonoids, enzymes, fatty acids, nucleotides, tannins, steroids, terpenoids, alkaloids, polyacetylenes, and vitamins (Table 10.1; Rovira 1969; Schönwitz and Ziegler 1982; Rice 1984; Uren 2000). Uren (2000) suggested that the amount of root exudates produced varies with the plant species, cultivar, the age of the plant, and substrate and stress factors.
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Inderjit, Weston, L.A. (2003). Root Exudates: an Overview. In: de Kroon, H., Visser, E.J.W. (eds) Root Ecology. Ecological Studies, vol 168. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-662-09784-7_10
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DOI: https://doi.org/10.1007/978-3-662-09784-7_10
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