GENIC ANALYSIS FOR PEROXIDASE ISOZYMES AND THEIR ORGAN SPECIFICITY INORYZA PERENNISANDO.SATIVA

Abstract

Peroxidase zymograms of the leaf blade, leaf sheath and lemma-palea were observed in progeny of crosses between strains of Oryza perennis Moench and O. sativa L. Bands OC, 2A, and 4A were found to be specified by codominant alleles, Px₁^OC, Px₁^2A, and Px₁^4A, respectively. These alleles produced hybrid bands 1A and 3 A in their heterozygotes. Regarding band 4C specified by Px₂^4C, (independent of Px₁), it was found that a perennis strain (W120-4, derived from an Indian natural population) had the band in the leaf sheath only, while another (W120-5, from the same population) showed it in the leaf blade only. Observations of their selfed progenies and hybrids suggested that there were two independent dominant genes repressing band 4C, one (R_LB^4C) acting in leaf blade and the other (R_LS^4C) acting in leaf sheath. On this basis, the organ-specific intensity variations of the 4C band observed in four different crosses could also be explained. These genes were considered to be "regulatory genes" repressing the activity of Px₂^4C.