Premium
Hybrid origin of “ Bauhinia blakeana ” (Leguminosae: Caesalpinioideae), inferred using morphological, reproductive, and molecular data
Author(s) -
Lau Carol P. Y.,
Ramsden Lawrence,
Saunders Richard M. K.
Publication year - 2005
Publication title -
american journal of botany
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.218
H-Index - 151
eISSN - 1537-2197
pISSN - 0002-9122
DOI - 10.3732/ajb.92.3.525
Subject(s) - caesalpinioideae , biology , bauhinia , botany , sympatric speciation , tribe , ficus , taxon , inflorescence , fabaceae , zoology , sociology , anthropology
Bauhinia blakeana (Leguminosae subfam. Caesalpinioideae tribe Cercideae), or the Hong Kong Orchid Tree, is of great horticultural value. It is completely sterile and is shown here to be the result of hybridization between the largely sympatric species, B. purpurea and B. variegata . Although the analysis of patterns of morphological variation revealed only a few examples of phenotypic intermediacy, study of intersimple sequence repeat (ISSR) markers enabled unequivocal identification of the parental species due to the presence of additive inheritance of alleles and the absence of any bands that are unique to B. blakeana . Investigation of aspects of the reproductive biology of the taxa furthermore revealed that the parental species are largely xenogamous, have flowering periods that overlap seasonally and temporally, and share common pollinators. Evidence is provided to show that B. blakeana is not naturally stabilized and is only maintained horticulturally by artificial propagation. It is therefore recommended that the hybrid be regarded as a horticultural cultivar rather than a naturally occurring species; a new cultivar name, Bauhinia ‘Blakeana’, is accordingly validated.