An AFLP diversity study of the genus Passiflora focusing on subgenus Tacsonia

DNA variation was studied at the intra- and interspecific levels within the genus #Passiflora#, with particular emphasis on the subgenus #Tacsonia# and its relationship with the subgenus #Passiflora#. AFLP fingerprints were generated for 35 accessions from 21 species, 14 of which belong to subgenus #Tacsonia#, and four to subgenus #Passiflora#. The morphologically intermediate #P. manicata# (subgenus #Manicata#) was also included, as were #P. trinervia# (subgenus #Psylanthus#) and #P. alnifolia# (subgenus #Decaloba#). The two latter were used as outgroup species. Two primer combinations generated 34-80 scorable fragments per genotype for a total of 260 fragments. Polymorphism analyses spanned the levels from individual genotype to section. Subgenus #Tacsonia# presented wide genetic variability at both intra- and interspecific levels, particularly within wild species. The classification based on these markers generally agrees well with current taxonomic definitions of common species, but less with definitions of sections. A geographical component was evident in the intraspecific variation of #P. mixta#, #P. tripartita# var. #mollissima# and #P. tarminiana#, with wider variation in Ecuador and Peru than in Colombia and Venezuela. These same three species. plus #P. cumbalensis#, formed adjacent clusters, showing closer affinity with each other than with the other species of subgenus #Tacsonia#. As expected, #P. manicata# clustered at an intermediate position between subgenera #Tacsonia# and #Passiflora#.