title: Anthocyanin pathway in rice (Oryza sativa L): identification of a mutant showing dominant inhibition of anthocyanins in leaf and accumulation of proanthocyanidins in pericarp.
abstract: The present study has surveyed a collection of indica rice (Oryza sativa) lines for tissue-specific anthocyanin pigmentation pattern, which has also been used for a genetically meaningful classification. This classification helped predict probable genotypes of rice lines and, in the process, a leaf blade-specific dominant inhibitor of pigmentation (Ilb) was predicted and its presence later confirmed in two lines. We ascribe most tissue-specific accumulation of anthocyanins to the presence of a different set of Pl alleles. Cyanidin, as a major pigment, and peonidin, as a minor pigment, were detected in purple-pigmented tissues. Further, the floral organ-derived tissues always contained a higher level of anthocyanins and, correspondingly, a relatively increased proportion of peonidin. One line, N22B, with a brown pericarp was identified and shown to accumulate proanthocyanidins, but with no anthocyanins, in the pericarp. We propose that the accumulation of proanthocyanidins is due to a block in the anthocyanin biosynthetic pathway in rice at the anthocyanidin synthase-mediated conversion of leucoanthocyanidin to anthocyanidin.
authors.affiliation: Plant Molecular Genetics Laboratory, Departement of Plant Sciences, School of Life Sciences, University of Hyderabad, 500134, AP, India.
authors.forename: V S
authors.initials: VS
authors.lastname: Reddy
authors.forename: S
authors.initials: S
authors.lastname: Dash
authors.forename: A R
authors.initials: AR
authors.lastname: Reddy