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Legume Genomics and Genetics (online), 2010, Vol. 1, No.1, 1-6
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Figure 4 The cluster map of core collections based AFLP data
above in the number of alleles, effective alleles, poly-
morphisms bands, and coefficient of genetic similarity,
genetic distance and gene diversity. Significance test
results showed that 40 core collection germplasms of
faba bean should be as representative in Qinghai whi-
ch could cover whole genetic information due to no
significant differences. Gene diversity (GD) and Nei’s
gene diversity for the total faba bean collection were
0.058 3 and 0.103 2, respectively, which respectively
increased 89.3% and 104.0%. The core collections con-
tained 20 landraces, 11 foreign varieties and 9 released
cultivars.
2 Discussion
2.1 Diversity analysis and germplasm classification
Germplasm resources of faba bean in Qinghai were
abundant in molecular diversity, particular in faba
landraces. The results are in agreement with those an-
alyses of genetic diversity based on morphological
traits using the same germplasm collections (Liu et al.,
2009). But there was obvious difference from the result
of germplasm classification. Using the Structure2.2
software, the genetic structure of faba bean in Qinghai
was analyzed to determine that 149 accessions could
be divided into seven groups, whereas three groups
were clustered based on the phenotyping data. The
classification results of germplasm resources were not
only related to the types of markers but also were
closely linked to classification method or foundation.
The results indicated that classification of germplasm
resources should not be completely classified by their
origin. The same types of germplasm resources also
had the genetic differences and certain genetic similarity.
The genetic distances among foreign germplasm were
relatively small compared to other germplasm resources
of faba bean in Qinghai. Therefore we suggested that
introducing elite foreign germplasm to enrich genetic
foundation of breeding of faba bean in Qinghai should
be quite necessary.
2.2 Construction of core collection of faba bean in
Qinghai
A core germplasm collection including 40 accessions
was constructed from 149 accessions based on AFLP
which contained genetic information accounting for
over 80%. whereas a previous core germplasm collec-
tion including 21 accessions was constructed from 153
accessions of faba bean in Qinghai based on morpho-
logical traits by Yang et al. There are significant coin-
cidences in the major characters between core collec-
tion and the whole tested samples, that was more than
90% (Yang et al., 2009). Although 149 accessions were
chosen as test material from 159 of faba bean which
were used by Yang et al., two core collections cons-
tructed by different markers were not the same at all.
The same material and method were adopted by both
sides, but their results were different. germplasms with
special characters were fully considered in the morpho-
logyical markers and while germplasm sources were
considered in the AFLP maker. Core collections were
constructed respectively based on released cultivars,
foreign varieties and landraces. Therefore, in order to
avoid the events of gene flow happen, it might be a
smart way to use core collection in the genetic improve-
ment, and also it is necessary to combine multiple me-
thods to construct core collection.
3 Materials and Methods
3.1 Materials
101 local landraces were used as research materials
which collected from the different counties with greatly
different ecological conditions (Haidong area, Haibei
county, Hainan county and Huangnan county of Qing
hai province). For comparison, 36 foreign varieties
and 12 released cultivars were employed as reference
research materials. Primer sequences were synthesized
by Shanghai Biological Chemical Company (table 5).
3.2 Procedures of DNA extraction and AFLP Reac-
tion protocols
The little modified CTAB procedure was applied to
5