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. 1991 Mar;95(3):804–807. doi: 10.1104/pp.95.3.804

Release and Modification of nod-Gene-Inducing Flavonoids from Alfalfa Seeds 1

Ueli A Hartwig 1,2, Donald A Phillips 1
PMCID: PMC1077609  PMID: 16668057

Abstract

Traces of luteolin, an important rhizobial nod gene inducer in Rhizobium meliloti, are released by alfalfa (Medicago sativa L.) seeds, but most luteolin in the seed exudate is conjugated as luteolin-7-O-glucoside (L7G). Processes affecting the production of luteolin from L7G in seed exudate are poorly understood. Results from this study establish that (a) seed coats are the primary source of flavonoids, including L7G, in seed exudate; (b) these flavonoids exist in seeds before imbibition; and (c) both the host plant and the symbiotic R. meliloti probably can hydrolyze L7G to luteolin. Glycolytic cleavage of L7G is promoted by glucosidase activity released from sterile seeds during the first 4 hours of imbibition. Thus, L7G from imbibing alfalfa seeds may serve as a source of the nod-gene-inducing luteolin and thereby facilitate root nodulation by R. meliloti.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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