Research

In collaboration with the University of Reading, this project used DNA fingerprinting techniques to investigate the origins of various cultivars of shrubby mallow. In the past they had been confusingly attributed to either L. olbia or L. thuringiaca with suggestions that they may be hybrids. For the study, species of wild origin were obtained and artificial hybrids were raised. Cultivars were also obtained from the originators. RAPD analysis was performed to assign parental origin of the cultivars. This was compared with morphological assessments of all the taxa. Results show that the majority of the cultivars are intermediate between L. olbia and L. thuringiaca, suggesting hybrid status and can be assigned to L. x clementii. A few cultivars were attributable to one or other of the species alone. It was not possible to discriminate between all recognisable cultivars using RAPD analysis.

Initial results were presented at an International Symposium under the aegis of the Commission of Biotechnology of ISHS, Molecular Markers for characterizing genotypes and identifying cultivars in horticulture at AGRO Montpellier, France, during 6 - 8 March 2000.

A full account was published as:
Grant, M, Miller, D & A. Culham. 2001. Genetic and morphological analysis of the origin and identity of perennial Lavatera (Malvaceae) cultivars. Journal of the American Society for Horticultural Science. 125(5): 593-598

Abstract: Knowledge of the origin of Lavatera L. (tree mallows) cultivars helps to predict their cultural requirements. Eighteen accessions representing 15 cultivars, 14 accessons of 7 species, and 5 accessions of an F1 hybrid between the putative parents of the cultivars were sampled for morphological variation and randomly amplified polymorphic DNA (RAPD) fingerprint variation. Species-specific molecular markers were identified from the RAPD profiles. Chimeral elements were not distinguishable by RAPD analysis. Principal component analysis identified the majority of the cultivars to be selections of hybrid origin, probably from a narrow genetic base. Two cultivars were derived directly from individual species. The resolving power of RAPD markers and morphology was similar although RAPD data offered greater ability to ascribe parentage while morphology offered optimal discrimination of cultivar selections.

Grant, M & A Culham. 1997. DNA fingerprinting and the identification of ornamental cultivars. The New Plantsman 4(2): 85-87.

Grant, M & A Culham. 1997. DNA fingerprinting and the identification of ornamental cultivars, part 2. The New Plantsman 4(3): 157-168.

Back to Introduction to research