International Journal of Horticulture, 2015, Vol.5, No.21, 1-45
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Bruna et al. (2006) used 150 sage genotypes of Salvia (Fam. Labiatae) coming from the African and the American
continents for the valorisation of new germplasm and used RAPD analysis to characterise several sage species and
to determine the genetic relationships among them. The primers used in their preliminary analysis allowed to
discriminate all 17 samples. The dendrogram by UPGMA cluster analysis was characterised by two main clusters:
in the first one all genotypes native to Mexico were grouped and, in a distinct sub-cluster, all cultivars of Salvia
greggii examined were collected. Genotypes coming from Somalia, Morocco and the Canary islands were
grouped together in the second major clade.
3 Discussion
Characterization is necessary for correct identification of plants. Correct identification is essential for various
purposes like solving taxonomic problems, to trace out phylogenetic relation, identification of hybrid and mutant
varieties, registration of new variety, plant variety protection etc. As mentioned, a wide range of classical and
modern methods are utilized for characterization. Each method is based on several parameters. From survey of
literature it is very clear that till date no single method and single parameter can justify correct identification of all
plant materials. But each method and parameter have logistic contribution for characterization. It is not necessary
that one should follow only one method for all characterization purpose. Nobody can recommend with present
knowledge only one technique for all purpose characterization. For a modern and industrialized floriculture there
is always demand and necessity for new varieties. Characterization and/or correct identification is most important
for documentation of variety. Any technique which can clearly differentiate the new variety from others should be
utilized whether it is classical or modern. Considering the limitations of each technique one should plan the
characterization programme on need basis. There are specific instructions for characterization whether for
taxonomic studies, registration to crop specific societies, plant variety protection etc. It has been clearly
mentioned in the review how cytological, morphological, palynological, biochemical and molecular characters can
be utilized for correct identification of plant. It has also been mentioned how technological advancement took
place considering the limitation of each technique. The system is at rapid developmental stage.
Cytological studies have solved many taxonomical problems. Karyotypic studies were reported to be of little use
in delineating cut-flower anthurium cultivars and hybrids (Marutani et al., 1993). The standard morphological and
physiological characters used for registration or granting plant breeders’ rights are adequate for determining
distinctness, uniformity and stability of the new mutant variety. Accurate identification of plants is desired for
patent protection, however, it is difficult to distinguish phenotypitally similar cultivars using morphological and
physiological methods or isozyme analyses. The limitation of these analyses is that they are observations of the
phenotype. It was observed that morphological and protein markers in anthuriums can easily be affected by
environmental factors and plant maturity (Kamemoto and Kuehnle, 1996). Moreover, such markers are known to
be often similar in closely related ornamental cultivars and not effective for identification purposes (Ricket al.,
2001) Isozymes have been widely used as biochemical markers, but their use is limited due to lack of
polymorphism and a small number of loci and alleles available for analysis. Variation in isozymes banding
patterns was found to be low among some cut flower anthurium cultivars indicating the limited utility of such
protein markers for cultivar identification purposes (Kobayashi et al., 1987). Isozyme markers were applied to
detect the genetic relationship among Calycanthaceae (Chang et al., 1995; Chen, 1995; Chen et al., 1999).
Phylogenetic relationship among species of the Calycanthaceae and genetic diversity of natural populations were
studied using DNA-based markers and more specifically using RAPD markers (Chen et al., 1999; Wen et al.,
1996). Maintenance of huge germplasm and use of classical classification resulted chances of duplications
(homonyms and synonyms) and therefore to prepare a correct core collection a wide range of parameters should
be used to eliminate duplications. Therefore, it was very important for using a sensitive and credible biochemical
and molecular technique to characterize and identify specific germplasm in addition to morphological and
agronomic traits.
Use of molecular markers in addition to classical methods provides more positive identification of new varieties.
Molecular markers are very versatile and can be used for a variety of purposes. Polymerase chain reaction (PCR)
