Molecular Plant Breeding 2016, Vol.7, No.20, 1
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8
1
Research Article Open Access
Variability, Heritability and Genetic Advance Analysis for Some Morphological
Characters in Oilseed Brassica Breeding Lines
Yared Semahegn , Misteru Tesfaye
Holetta Research Center, Ethiopian Institute of Agricultural Research, P. O. Box 2003, Addis Ababa, Ethiopia
Corresponding author Email:
Molecular
Plant
Breeding,
2016,
Vol.7,
No.20
doi:
Received: 05 Apr., 2016
Accepted: 08 May, 2016
Published: 17 May, 2016
Copyright © 2016
Yared and Misteru, 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
:
Yared S., and Misteru T., 2016, Variability, Heritability and Genetic Advance Analysis for Some Morphological Characters in Oilseed Brassica Breeding Lines,
Molecular
Plant
Breeding, 7(20): 1-8 (doi
Abstract
Sixty four Brassica breeding lines were investigated for some morphological characters to identify the extent and nature
of genetic variability and determine the heritability and genetic advance during 2014 cropping season. Analysis of variance showed
the existence of considerable genetic variation among the lines for further selection and hybridization efforts. The maximum number
of secondary branches/plant was observed by the breeding line code≠64. The highest yield/plot was recorded by the breeding line
code≠48 followed by the breeding line code≠25 and code≠64. Breeding line code≠53 exhibited the maximum 1 000 seed weight.
Cluster analysis categorized the breeding lines into nine clusters. All lines were grouped regardless of their pedigree record which
might be the result of selection pressure applied on different morphological characters. 71.1% of the variation was explained by the
first three principal components as described by the principal component analysis. Number of secondary branches/plant and
yield/plot were among the major positive contributor while 1 000 seed weight had negative contribution in the first principal
component in which 32% of the variation was explained. These characters also recorded high heritability values in broad sense along
with high genetic advance as percent of mean for which early generation selection would be effective in improvement program.
Keywords
Brassica breeding lines; Analysis of variance; Cluster analysis; Principal component analysis; Heritability; Genetic
advance as percent of mean
Introduction
Brassica carinata commonly called Ethiopian mustard predominantly cultivated in Ethiopia since ancient time,
which is used for oil, condiments, medicines and vegetables (Riley and Belayneh, 1982). It covered 44 041
hectares of land, and produced 62 450.27 tons with productivity of 1.42 ton/ha (CSA, 2013/14). Brassica napus
was also grown in state farms in 1990s, but it could not be sustained due to diseases outbreak such as blackleg
(Leptosphaeria maculans). Currently, some hybrid and open pollinated varieties of B. napus and B. juncea, which
are canola type and disease resistant, were introduced by private companies and tested for adaptation, and as a
result, some varieties have been registered by National Variety Release Committee (NVRC) for production in the
country. However, such varieties are very expensive to procure and costly to be grown by small scale farmers in
developing countries like Ethiopia. Despite unsuccessful efforts in developing canola type B. carinata so far, in
order to tap the potential of this crop as an oilseed, developing disease resistant, canola type and high yielding
varieties with desirable agronomic traits remains the primary objective of oilseed Brassica breeding in Ethiopia.
As genetic diversity is a prerequisite for any breeding program of developing improved varieties or hybrids,
understanding the extent and nature of this diversity is essential for enhancing the breeding efforts such as
selection and hybridization. Several researches on the extent and nature of genetic variation have been done for
various crops including Brassica species (Mailer et al., 1997; Alemayehu and Becker, 2002; Mahasi and
Kamundia, 2007; Abbas et al., 2008; Uysal et al., 2010; Golkar et al., 2011; Khodadadi et al., 2011; Žiarovská et
al., 2012; Ahmad et al., 2013; Kumar et al., 2013; Nasim et al., 2013; Iqbal et al., 2014; Shafari et al., 2015).
Heritability and genetic advance studies were also done by several researchers (Ali et al., 2013; Nasim et al., 2013;
Bind et al., 2014; Synrem et al., 2014). The objective of this study was to identify the extent and nature of genetic
variability and determine the heritability and genetic advance for morphological characters of oilseed Brassica
