International Journal of Horticulture, 2015, Vol.5, No.21, 1-45
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the cultivars into four main clusters which did not relate to cultivar provenance or origin and were independent of
floral colour and spathe category. RAPD markers fingerprinting allowed a rapid assessment of the level of genetic
variation that would otherwise be difficult to evaluate using the limited number of morphological markers present
among these closely related anthurium cultivars. Ranamukhaarachchi et al. (2001) utilized RAPD to determine the
genetic relationships of nine morphologically similar pot plant cultivars of Anthurium sp. by developing DNA
fingerprints (DFP). All cultivars tested exhibited a high degree of genetic similarity. Study showed that the nine
Anthurium cultivars examined were genetically closely related indicating that RAPDs can be a useful tool to
distinguish Anthurium pot plant cultivars as well as identify their genetic relationships.
Molecular cytogenetic characterization, genetic variability and phologeny have been investigated on different
species of snapgragon (
Antirrhinum subaecticum, A. majus etc.)
using molecular markers (Jiménez et al., 2002,
2005; Zhang et al., 2005).
PCR-based DNA markers were examined on two cultivars of Asiatic Hybrid lily using random primers with
various lengths (10-, 12-, 15- and 20-base). Thirty-three out of61 (54%) 15-base primers and 14 out of 21 (67%)
20-base primers generated polymorphic fragments whereas 17 out of 145 (12%) and 4 out of 24 (17%) of the 10-
and 12-base primers, respectively, amplified them. The efficiency of the RAPD reaction increased with increasing
primer length. They also examined inter-simple sequence repeat (ISSR) reactions using 30-anchored simple
sequence repeat (ASSR) primers, and found 33 out of 63 (52%) primers that amplified polymorphic bands
between the two cultivars are genetically stable (Yamagishi et al., 2002).
Bougainvillea
(Fam. Nyctaginaceae) is one of the most important perennial ornamental shrubs, sometimes
climbers, in tropical and subtropical gardens. Three species of
Bougainvillea
i.e.
B. spectabilis, B. glabra
and
B.
peruviana
are important horticultural species, showing colourful bracts. Considering the importance and utility of
genetic diversity, The National Botanical Research Institute (NBRI), Lucknow, India is maintaining a rich
Bougainvillea
germplasm collection of approx. 180 species/cultivars comprising both single bracted and double or
multi-bracted varieties. NBRI has detected, induced, isolated, established and commercialized a series of new
varieties developed through spontaneous mutation, selective hybridization, chromosome management through
colchicine treatment and gamma ray-induced mutation. Studies have solved many taxonomic problems and
phylogenetic relationships, and have also opened a new way to synthesize new varieties through chromosomal
manipulation.
Chromosome numbers of horticultural varieties of
Bougainvillea
have been reported by a number of workers(Sen
and Sen, 1954; Sharma and Bhattacharya, 1960; Ninan et al., 1959; Banerji and Banda, 1967; George and
Sobhana, 1976; Begum and Datta, 1971). Basic cytogenetic studies were directed towards determination of
chromosome number, mitotic and meiotic divisions, karyotype analysis, colchi-ploidy etc. DNA content has been
estimated from three basal
Bougainvillea
species, hybrid groups, and triploid hybrid cultivars and induced
tetraploids and their relationships established. These studies have solved many taxonomic problems and
phylogenetic relationships, and have also opened a new way to synthesize new varieties through chromosomal
manipulation. Taxonomical studies were initiated on important
Bougainvillea
species and cultivars to enrich
information on morphological descriptions, growth habit, agro-technology, techno-economics, flowering
behaviour, biochemical (TLC), affinities with coloured illustrations and their usage (Datta, 1985; Jayanyhi et al.,
1999). RAPD analysis was performed to determine the genetic relationships among the most important
Bougainvillea
cultivars grown at National Botanical Research Institute, India. Fifty random decamer primers were
screened and ten were selected for final RAPD analysis. These 10 primers used in this analysis yielded 167
scorable bands with an average of 11.3 bands per primer. Of the 167 fragments scored from these primers, 26 were
monomorphic and 141 were polymorphic (84.4%). The generated similarity matrix showed that the genetic
diversity within the tested genotypes was high (average similarity index=30.1%). Similarity values among the
studied genotypes ranged from 6% to 89%. The resulting dendrogram divided the cultivars into two main clusters.
The first contained 37 varieties and was divided into two sub-clusters at a similarity value of 0.03 with 21 and 16
varieties in each subcluster, respectively. Subcluster I included those cultivars which had affinity with buttiana
