Assessment of genetic variability in the Bougainvillea varieties using morphological and molecular markers

Abstract

Bougainvilleas are important ornamental climbing shrubs grown all over the world for their colourful bracts. For developing improved varieties it requires knowledge of their genetic variability for selection of parental generation. Here, we examined the genetic variability among 48 Bougainvillea varieties using two DNA fingerprinting methods viz., Directed Amplification of Minisatellite DNA (DAMD) and Inter Simple Sequence Repeat (ISSR). Out of total 290 bands obtained with 15 (5 DAMD and 10 ISSR) primers, 266 bands were polymorphic, accounting for 91% polymorphism amongst Bougainvillea varieties. The polymorphic information content (PIC) value varied from 0.07-0.27 in DAMD and 0.13-0.34 in ISSR primers, respectively. The cumulative genetic distance calculated by Jaccard’s coefficient method showed a distance range from 0.17-0.60 with an average value of 0.41 among all the varieties of Bougainvillea. The maximum inter-varietal average genetic distance (0.60) was found between varieties ‘Mary Palmer Special’ and ‘Kumbiegel’ while the corresponding least genetic distance (0.17) was between ‘Silver Line’ and ‘Feathery Fantasy’. Wide range of pair-wise genetic distances and percentage of polymorphism revealed that Bougainvillea varieties are genetically much diverse. These results suggest that the current collection of Bougainvillea germplasm have vast genetic variations. DAMD and ISSR analyses have identified the diverse Bougainvillea varieties (‘Mary Palmer Special’, ‘Kumbiegel’, ‘Gopal’, ‘Vithal Variegata’, ‘Mataji Agnihotri’, ‘Manohar’, and ‘Palekar’), which could be further utilized in various genetic improvement programmes including conventional as well as marker assisted breeding towards development of new and desirable Bougainvillea varieties.