Indian Society of Genetics & Plant Breeding

R1-nj expression in parental inbreds as a predictor of amenability of maize hybrids to R1-nj-based doubled haploid development

Published on

The current method of doubled haploid (DH) development
in maize involves
in vivo production of haploids using R1-
nj
-based haploid inducer lines that upon use as male render
a small fraction of seed in the pollinated female ears haploid.
Identification of haploid seed relies on
R1-nj marker
expression in the endosperm and embryo, and the degree
of its expression determines efficiency of DH development
process. In the present study,
R1-nj expression in the
endosperm was characterized in crosses of CIMMYT’s
R1-
nj
-based haploid inducer TAILP1 with a set comprising 18
early maturity hybrids and their 23 parental inbreds. Kernel
colour inhibition was observed only in a small proportion
of the hybrids and inbreds. Comparison of
R1-nj expression
in the hybrids and their parental inbreds revealed a distinct
pattern, which may be useful in identifying source
populations and/or determining parental constituents for
synthesizing source populations with predicted amenability
to doubled haploid development using
R1-nj-based haploid
inducers. However, deviation from the pattern was noted
in hybrids involving inbreds with higher degree of colour
inhibition, which suggests complex nature of
R1-nj
phenotype expression and necessitates further
investigation involving larger sets of germplasm for
dissecting the role of maternal and paternal genetic factors
in determining
R1-nj phenotype expression. The hybrids
found exhibiting complete kernel anthocyanin expression
in present study can be used directly as source populations
for DH development using
R1-nj based haploid inducers.
Besides, since the inbreds used in the study have originated
from and/or are accessible to CGIAR/NARS maize breeding
programmes, the information on their kernel anthocyanin
expression can be helpful in selection of source populations
or generating new source populations amenable for DH
development using
R1-nj based haploid inducers.  

Keywords: Maize, haploid inducer, R1-nj expression, doubled haploid, amenability

Info

Year: 2019
Volume: 79
Issue: 4
Article DOI: 10.31742/IJGPB.79.4.5
Print ISSN: 0019-5200
Online ISSN: 0975-6906

Authors

info_circle

Download PDF