Distribution of phenolic compounds in rice seedlings under Cr exposure

Abstract

Responses of phenolic compounds were hydroponically investigated in rice seedlings (Oryza sativa L. cv. XZX 45) treated with either Cr(III) or Cr(VI). Results indicated that rice seedlings are able to effectively sequester both species of Cr. Majority of Cr recovered in plant materials was accumulated in roots rather than shoots. Accumulation of total soluble phenolics, flavonoids and lignin in plant materials was quite evident due to Cr exposure, but displaying different responses between the two species of Cr. Distribution of total soluble phenolics and flavonoids was more at shoots, especially at younger segments of shoots, and less at roots, whereas the lignin content was detected more at the younger parts of shoots and less towards the root tips. It is suggestive from the current investigation that both Cr species caused production and accumulation of these secondary metabolites in rice seedlings.