Analysis of Molecular Diversity and Differentiation of Red and White Kernel Rice Varieties

Abstract

Colour of the rice kernel is an important characteristic in commerce. Rice kernels having white colour are preferred
in the national and international markets. The red colour of the kernels is preferred by consumers in some regions
of India particularly in the southern state, Kerala. Therefore, development of varieties with specific kernel colour
is an important breeding objective. A number of red and white kernel varieties have been bred. No systematic
attempt has been made to understand the extent of diversity within and between these two distinct phenotypic
classes. In the present study, RAPD markers were employed to analyze the genetic relationship among 20 varieties
of each kernel colour classes and to identify marker (s) that can be used to differentiate the red and white kernel
types from each other. The genetic diversity analysis among red and white kernel rice varieties using different
DNA amplicons grouped 40 varieties into two major clusters. The maximum diversity was observed between two
red kernel varieties, i.e., ‘Ptb 5’ and ‘Jyothi’ followed by distance between two white kernel varieties ‘Rohini’
and ‘Ptb 14’, and two red kernel varieties ‘Remanika’ and ‘Jyothi’. These varieties may be selected as parents
for hybridization progrmme. DNA pooling strategy was adopted to identify molecular marker(s) for kernel colour.
A total number of 145 random decamer primers were screened to identify highly polymorphic well-resolved specific
bands for kernel colour. OPC-121200 was indicated as a putative molecular marker for red kernel colour and OPK-
141000 as a putative molecular marker for white kernel colour in rice.