Investigating the parentage of the cultivars of Crocus chrysanthus and C. biflorus

RHS project team

Kálmán Könyves

Partners

Supervised by Dr Alastair Culham (University of Reading) and Dr Dawn Edwards (RHS).

Start date

01/02/2007 09:29:40

End date

01/02/2008 09:29:45

Keywords

Crocus chrysanthus, Crocus biflorus, atpH, atpF, matL, ndhF, trnH, psbA, sequence variation, DNA analysis, morphology, Ard Schenk, Blue Pearl, Blue Bird, Prins Claus, Parkinsonii

The problem

The origin of many cultivars of Crocus chrysanthus and C. biflorus is unknown. Previous studies have suggested that the cultivars are either derived from just one of the species or are hybrids between the two species.

Approach

The cultivars were investigated using four plastid regions, atpH-atpF, matK, ndhF and trnH-psbA, and the nuclear ribosomal ITS region. Including the putative parents (Crocus chrysanthus and C. biflorus), 14 species and 11 subspecies were sampled, to assess the discriminatory power of the regions. There were 309 variable sites characterised in all regions, which could be used to separate the species and subspecies.

NdhF performed the best, distinguishing 11 species and six subspecies. Since the sequence variation between the species and the subspecies was low, morphological data was used to help trace the ancestry of the cultivars.

Benefits to gardeners

This project will help to bring stability to the names of these Crocus cultivars.

Summary of results

Crocus ‘Ard Schenk’, ‘Blue Pearl’ and ‘Blue Bird’ seemed to derive from C. biflorus subsp. pulchricolor, and C. ‘Prins Claus’ from C. biflorus subsp. alexandri. The origin of C. ‘Parkinsonii’, a clone of C. biflorus subsp. biflorus from Italy, was congruent with previous literature. To ascertain the origin of the other cultivars of C. chrysanthus and C. biflorus, rigorous morphological studies will be needed, together with further DNA analysis.