Polyphenols, Including the New Peapolyphenols A???C, from Pea Root Exudates Stimulate Orobanche foetida Seed Germination

Three new polyphenols, named peapolyphenols A???C, together with an already well-known polyphenol and a chalcone (1-(2,4-dihydroxyphenyl)-3-hydroxy-3-(4-hydroxyphenyl)-1-propanone and 1-(2,4-dihydroxyphenyl)-3-(4-methoxyphenyl)propenone) were isolated from pea root exudates. They were found to strongly stimulate Orobanche and Phelipanche species seed germination. Interestingly, only peapolyphenol A, 1,3,3-substituted propanone, and 1,3-disubstituted propenone had specific stimulatory activity on O. foetida, excluding any other Orobanche or Phelipanche species tested. This species specificity is relevant, as O. foetida does not respond to the synthetic strigolactone analogue GR24, commonly used as a standard for germination assays. As characterized by spectroscopic methods, peapolyphenols A???C proved to be differently functionalized polyphenols with hydroxy and methoxy groups on both the aromatic rings and the propyl chain

Polyphenols, including the new peapolyphenols A-C, from pea root exudates stimulate orobanche foetida seed Germination

Three new polyphenols, named peapolyphenols A-C, together with an already well-known polyphenol and a chalcone (1-(2,4-dihydroxyphenyl)-3-hydroxy-3-(4- hydroxyphenyl)-1-propanone and 1-(2,4-dihydroxyphenyl)-3-(4-methoxyphenyl) propenone) were isolated from pea root exudates. They were found to strongly stimulate Orobanche and Phelipanche species seed germination. Interestingly, only peapolyphenol A, 1,3,3-substituted propanone, and 1,3-disubstituted propenone had specific stimulatory activity on O. foetida, excluding any other Orobanche or Phelipanche species tested. This species specificity is relevant, as O. foetida does not respond to the synthetic strigolactone analogue GR24, commonly used as a standard for germination assays. As characterized by spectroscopic methods, peapolyphenols A-C proved to be differently functionalized polyphenols with hydroxy and methoxy groups on both the aromatic rings and the propyl chain. © 2010 American Chemical Society.This work was supported by a grant from the Italian Ministry of University and Research (MIUR) and by the Spanish project AGL2008-01239.Peer Reviewe