Analysis of inheritance in a novel seedling stage zebra leaf mutant, Pusa Zebra 18 in rice (Oryza sativa L.)

Abstract

A novel zebra leaf mutant, Pusa Zebra 18 derived spontaneously from F2 intercross population of Pusa 44 near-isogenic lines (NILs) exhibits distinguishable yellowish cross bands across the green leaf blade, specifically expressed in the seedling stage from 6 DAT, which diffuses progressively, leading to the recovery of the normal green leaf by 30 DAT. We elucidated the genetics and nature of inheritance for zebra trait in F2 and BC1F2 populations by crossing Pusa 6B with Pusa Zebra 18. The leaves of the F1 were a normal green color, indicating that the seedling stage zebra leaf trait in Pusa Zebra 18 is recessive. Chi-square goodness of fit analysis of these segregating populations showed that the segregation ratio was fitting to the Mendelian segregation ratio of 3:1. The seedling stage zebra leaf mutation in Pusa Zebra 18 is monogenic recessive in nature. Further, mapping, fine mapping, cloning, and functional characterization need to be carried out, which will help gain insight into the mechanism involved in chlorophyll biosynthesis and regulation studies in rice.