Phylogenetic implications of chloroplast DNA restriction site variation in subtribes Raphaninae and Cakilinae (Brassicaceae, tribe Brassiceae)

Chloroplast DNA restriction site data was used to assess relationships among 41 taxa of the subtribes Raphaninae and Cakilinae (tribe Brassiceae, Brassicaceae). A total of 456 restriction site mutations was observed, with 237 (52%) being phylogenetically informative. Cladistic analysis, based on Wagner parsimony analysis, indicated four major clades: (i) CAKILE, (ii) CRAMBE, (iii) NIGRA lineage, and (iv) RAPA-OLERACEA lineage. The CAKILE clade was divided into two lineages: (i) Cakile, Erucaria (including Reboudia), and Didesmus (previously assigned by Schulz to the Raphaninae) and (ii) Crambella (previously assigned by Schulz to the Raphaninae). The Raphaninae as currently circumscribed is polyphyletic in origin. The cpDNA data supported separate subtribal status for Crambe (Raphaninae) and indicated two major lineages corresponding to sect. Dendrocrambe and the combined sections Crambe and Leptocrambe. Enarthrocarpus arcuatus, Enarthrocarpus lyratus, Morisia monanthos, Raphanus raphanistrum, Raphanus sativus, and Rapistrum perenne were included in the RAPA-OLERACEA lineage of subtribe Brassicinae. Ceratocnemum rapistroides, Cordylocarpus muricatus, Guiraoa arvensis, Hemicrambe fruticulosa, Kremeriella cordylocarpus, Muricaria prostrata, Otocarpus virgatus, Raffenaldia primuloides, and Rapistrum rugosum were included in the NIGRA lineage of subtribe Brassicinae. Key words: Brassicinae, Raphaninae, Cakilinae, chloroplast DNA restriction site variation, molecular systematics.

Evaluation of the subtribes Moricandiinae, Savignyinae, Vellinae, and Zillinae (Brassicaceae, tribe Brassiceae) using chloroplast DNA restriction site variation

Chloroplast DNA restriction site data was used to assess relationships among 21 taxa of the subtribes Moricandiinae, Savignyinae, Vellinae, and Zillinae (tribe Brassiceae, Brassicaceae). A total of 301 restriction site mutations was observed, with 154 (51.2%) phylogenetically informative. Cladistic analyses, based on Wagner and Dollo parsimony, indicated two major clades. One of these, the Vellinae–Zillinae clade, included members of the Vellinae and Zillinae, with a clarification of the positions of certain genera. The second, the Brassicinae : Rapa–Oleracea clade included Brassica rapa, Moricandia, Pseuderucaria, and Rytidocarpus. The position of Henophyton (Savignyinae) was not clearly resolved. Within the Vellinae–Zillinae clade, two main lineages were evident: (i) Vellinae-core clade, which includes Boleum, Carrichtera, and Vella (all members of the Vellinae) and Euzomodendron (Savignyinae); (ii) Zillinae clade, which includes Fortuynia, Physorrhynchus, Zilla (all Zillinae), and Foleyola and Schouwia (assigned to Moricandiinae and Vellinae, respectively). The positions of Psychine and Succowia (both assigned to Vellinae) were not clearly resolved in the strict consensus but were aligned with the Vellinae-core clade in almost all of the most-parsimonious Wagner trees. The cpDNA data did not support the current separate subtribal ranking for the Moricandiinae but instead revealed the genetic similarity of Moricandia, Pseuderucaria, and Rytidocarpus to subtribe Brassicinae. Key words: Brassicinae, Moricandiinae, Savignyinae, Vellinae, Zillinae, molecular systematics.

Molecular relationships in subtribe Brassicinae (Cruciferae, tribe Brassiceae)

Restriction-site variation for 17 endonucleases was compared in the large single-copy region of the chloroplast genome in 74 taxa of the genera Brassica, Coincya, Diplotaxis, Eruca, Erucastrwn, Hirschfeldia, Raphanus, Sinapidendron, Sinapis, and Trachystoma (subtribe Brassicinae, tribe Brassiceae, Cruciferae). A total of 422 restriction-site mutations was observed, with 228 (54%) showing variation among taxa. Phylogenetic analyses indicated a clear division of the subtribe into two main lineages designated here as Rapa–Oleracea and Nigra. Polyphyly was evident in five genera (Brassica, Diplotaxis, Erucastrum, Sinapis, and Trachystoma) as indicated by their placement in both lineages and (or) further separation into groups within a lineage. The genera Coincya, Hirschfeldia, and Sinapidendron were monophyletic within the Nigra lineage, as were Eruca and Raphanus in the Rapa–Oleracea lineage. Four major groups were recognized within each lineage. The lowest levels of chloroplast DNA divergence were observed among taxa belonging to the same cytodeme or crossing group and were highest for Brassica rapa and Brassica oleracea versus Brassica nigra at 2.10–3.91% and 2.00–3.78%, respectively. The chloroplast DNA data were incongruent with traditional taxonomic circumscription of 5 of the 10 genera but concordant with other data sets that support the close genetic relatedness of all 10 genera. Key words: Brassica, Coincya, Erucastrum, Sinapidendron, Trachystoma, chloroplast DNA restriction-site variation.