International Journal of Horticulture, 2015, Vol.5, No.21, 1-45
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technology was introduced around 1990 (Saiki et al., 1988; Erlich et al., 1991). This technique enabled one to
detect differences at the DNA sequence level in an easy and fast way, even if only small amounts of tissue are
available. Williams et al. (1990) introduced the use of general purpose ten-mer primers in the RAPD technique.
Wolff et al. (1993, 1995) showed that using the RAPD technique reproducible patterns were obtained in
chrysanthemum and that with these patterns cultivars could be distinguished. The RAPD assay has been
successfully used for studying genetic diversity of many crop species such rose (Debener and Mattiesch, 1996),
chrysanthemum (Huang et al., 2000), Amaranthus (Faseela and Salkutty, 2007) etc. RAPD is most commonly
used for the identification of cultivar/variety due to its simplicity, rapidity and requirement of only a small
quantity of DNA to generate numerous polymorphisms. RAPD is a sensitive method of detecting genetic variation
and has the advantage of being quick and easy, requiring little plant material, and having a high resolution. RAPD
is a powerful technique for determining inter - and intra - specific DNA variation. Characterization of different
ornamental cultivars and species using RAPD technique has been most successful. This technique has also been
very suitable for confirmation of parent-hybrid relationship and to differentiate mutants from original variety.
It has been proved experimentally that DNA markers provide a powerful tool for identification of cultivars and
species (Prevost and Wilkinson, 1999; Pasaˇkinskiene et al., 2000), phylogenetic evaluation (Wang et al., 1998;
Blair et al., 1999), tagging and marker aided selection of agronomically important genes (Akagi et al., 1996;
Ratnaparkhe et al., 1998; Hittalmani et al., 2000), linkage map construction and the mapping of quantitative traits
loci (Debener and Mattiesch, 1999; Dunemann et al., 1998; Garcı´a et al., 2000; Takeuchi et al., 2001) (QTL). A
number of DNA markers are necessary for these studies, especially for map construction, tagging and QTL
mapping. RAPD markers have been developed to determine the hybridism of inter-specific hybrids in Lilium
(Yamagishi et al., 1995; Obata et al., 2000). However, the number of DNA markers is still insufficient because
when 10-base primers were used for RAPD analysis in Lilium species and hybrids only 16% of them amplified
polymorphic bands (Yamagishi et al., 1995). Therefore, it was necessary to develop new DNA markers for geneti c
evaluation of horticulturally important traits in
Lilium
. In Cherokee rose, Rosa laevigata Minchx, accessions,
RAPD analysis allowed the identification of the erroneous classification of the hybrid `Silver Moon' (Walker and
Werner, 1997). Simple experimental procedures, requirement of minimal amount of plant tissue and the possibility
of automation by the use of a laboratory robot (Terzi, 1997), RAPD analysis was found to be very useful in
Alstroemeria breeding for rapid and early verification of hybridity in large seedling populations. RFLP analysis is
hardly used to generate DNA markers in Lilium because of the genome size in Lilium species. Therefore,
PCR-based markers such as RAPD and inter-simple sequence repeat (ISSR) markers were found to be useful to
generate DNA markers in Lilium. Although 10-base random primers have been usually used for RAPD analysis in
plant species, the usefulness of 15-and 20-base primers to amplify polymorphic bands in rose was shown by
Debener and Mattiesch (Debener and Mattiesch, 1998, 1999). ISSR markers that amplify the genomic sequence
between two simple sequence repeats (SSRs or microsatellite) using SSR primers have also generated many
polymorphic DNA markers in several crops (Prevost et al., 1999; Wang et al., 1998; Blair et al., 1999; Akagi et al.,
1996; Ratnaparkhe et al., 1998).
Many ornamental plant species develop mutants through sports. Most easily detectable are mutations with
changed morphological traits specially flower colour. Mutants are often discovered by others than the breeder of
the original variety. The discoverer can obtain plant breeders’ rights for such mutants when they are shown to be
distinct from all existing varieties, including the original variety. In ornamentals there are regular development of
new varieties through induced mutagenesis. To protect the interests of the breeder of the original variety the
International Union for the Protection of New Varieties of Plants (UPOV) has introduced the concept of an
‘essentially derived variety’ (EDV). This concept, which is described in the UPOV (1991) Act of 1991, extends
the scope of protection of the initial variety to any variety essentially derived from it. Therefore, all rights given to
the breeder of the initial variety also apply to the EDV
/). Morphological characterization is
sufficient for registration of new ‘sports’ or ‘mutants’ with changed phenotypic characters. However, these
characters appear less suitable for relating mutants to the original variety, as they do not seem to allow an accurate
determination of genetic conformity. Mutants usually are the result of just very few changes in the genetic makeup
