Maize Genomics and Genetics 2015, Vol.6, No.2, 1-5
1
Research Report Open Access
Molecular Characterization of Selected Maize (
Zea mays
L.) Inbred Lines
Tandzi L.N. , Ngonkeu E.L.
Department of Crop Improvement, CSK Himachal Pradesh Krishi Vishvavidyalay, Palampur (HP), 176062, India
Corresponding author email:
Maize Genomics and Genetics, 2015, Vol.6, No.1 doi:
10.5376/mgg.2015.06.0002
Received: 03 Oct., 2015
Accepted: 26 Oct., 2015
Published: 30 Oct., 2015
Copyright
©
2015 Tandzi L.N. and Ngonkeu E.L., This is an open access article published under the terms of the Creative Commons Attribution License, which
permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Preferred citation for this article:
Tandzi L.N. and Ngonkeu E.L., 2015, Molecular Characterization of Selected Maize (
Zea mays
L.) Inbred Lines, Maize Genomics and Genetics, Vol.6, No.2,
1
-
5 (doi:
10.5376/mgg.2015.06.0002
)
Abstract
Genetic knowledge of germplasm diversity among parental inbred lines has significant impact in the development of
improved maize hybrids in the breeding program. The aim of our study was to assess maize inbred lines for variability in molecular
traits and to estimate genetic distance among different parental lines. Maize inbred lines were genotyped through 200 SNPs markers.
The results revealed low levels of variability across the lines. Two major clusters of lines were observed where the first major group
was made of 16 sub-groups of 28 lines. The genetic distance between the studied lines was low. Therefore, the prediction of the
heterosis effect of the crosses between the maize parental lines would have been in the negative way.
Keywords
Inbred line; SNP marker; Variability; Genetic distance
Introduction
Genetic diversity is the average sequence divergence
between any two individuals for a given loci (Ahmad
et al., 2010). The strategies used in maize breeding
programs are frequently characterized by a decrease of
genetic diversity in the pool of germplasms and an
increase in the genetic evenness in cereal production
(Lee, 1998; Morales
et al., 2010). This might cause
important problems, particularly sensitivity to new
diseases and/or a decreased tolerance to high temperatures
or drought (Duvick, 1989).
Different methodologies have been used to characterize
genetic diversity in the maize germplasm including
morphological characters, pedigree analysis, heterosis
and the detection of variation at the DNA level using
markers (Udaykumar et al., 2013). The advent of
molecular genetics has enhanced selection accuracy
for quantitative traits by incorporating molecular
information into genetic improvement programs (Tang
and LI, 2006). Analysis of genetic diversity and
relationships among the elite breeding materials can
significantly aid in crop improvement. In maize, this
information is useful in planning for hybrid and line
development, assigning lines to heterotic groups and
in plant variety protection (Yuan et al., 2002; Yadav
and Singh, 2010).
Morphological and molecular studies of inbred lines
have not yet been undertaken under acid soils of the
Humid Forest Zone of country. For an effective and
efficient national maize breeding program in the
Cameroon, there is an urgent need to gather useful
information in this regard.
The objectives of the present study were to: Assess
maize inbred lines for variability in molecular traits;
Estimate genetic distance among different parental lines.
1 Results
1.1 Grouping of inbred lines based on SNPmarkers
Clusters were generated through DARwin by a simple
matching dissimilarity index, a threshold equality of
0%, with 15 nodes (degree: minimum = 2, maximum
= 3) (Figure 1). The edge length sum of the graph was
0.46. Different colors were applied to discriminate
introduced inbred lines from the local (lines from
IRAD were in black color). Two major clusters of
lines were observed: group one include 28 inbred lines
and the second group two lines (ATP S6 31Y-2 and
ATP S6 20Y-1). The first group was divided into 16
sub-clusters: the first 10 sub-clusters each contained
one line. The sub-cluster k, l and m had 2 lines each, n
had 5 lines, o had 4 lines and p had 4 lines (Table 1).
The introduced inbred lines were colored in blue while
