Systematics and phylogeny of the Brassicaceae (Cruciferae): an overview

Abstract

Abstract. A critical review of characters used in the systematics of the Brassicaceae is given, and aspects of the origin, classification, and generic delimitation of the family discussed. Molecular phylogenetic studies of the family were reviewed, and major clades identified. Based on molecular studies, especially from the ndhF chloroplast gene, and careful evaluation of morphology and generic circumscriptions, a new tribal alignment of the Brassicaceae is proposed. In all, 25 tribes are recognized, of which seven (Aethionemeae, Boechereae, Descurainieae, Eutremeae, Halimolobeae, Noccaeeae, and Smelowskieae) are described as new. For each tribe, the center(s) of distribution, morphology, and number of taxa are given. Of the 338 genera currently recognized in the Brassicaceae, about 260 genera (or about 77%) were either assigned or tentatively assigned to the 25 tribes. Some problems relating to various genera and tribes are discussed, and future research developments are briefly covered.

Fast Diploidization in Close Mesopolyploid Relatives ofArabidopsis

“…Our data strongly advocate Pachycladon as a member of the paraphyletic tribe Camelineae as proposed by Al-Shehbaz et al (2006) and do not support the position of the maternal parent (the Brassica gene copy) close to the split of Lineage I and II (Joly et al, 2009). Although it is not possible to reject the null hypothesis of a single allopolyploid origin for Pachycladon and the Australian endemics, less diploidized (n = 10) Pachycladon species appear to originate and radiate on the South Island of New Zealand more recently (1.6 to 0.8 mya; Joly et al, 2009).…”

“…The analyses were performed with a particular emphasis on Pachycladon species (Camelineae; Al-Shehbaz et al, 2006), which were also shown to have an allopolyploid origin (Joly et al, 2009).…”

Karyology of Plants Growing on Serpentines in Bulgaria

“…All investigated species from Brassicaceae are polyploids. AL-SHEHBAZ et al (2006) pointed out that polyploidy and aneuploidy had played an important role in the speciation processes in Brassicaceae. The lack of sufficient karyological information for the investigated taxa does not give us reason for comparisons and conclusions about the changes in ploidy level under the influence of the serpentine substrate.…”

Phylogeny of <i>PolA1</i> Gene Consistent with the Relationships of U’s Triangle in <i>Brassica</i>

“…The family Brassicaceae contains about 338 genera and 3709 species (Al-Shehbaz et al, 2006). Three amphidiploid species, namely, B. juncea (2n = 36, AABB), B. napus (2n = 38, AACC), and B. carinata (2n = 34, BBCC), were derived from hybridization between diploid species, namely, B. rapa (2n = 20, AA), B. nigra (2n = 16, BB), and B. oleracea (2n = 18, CC) (Morinaga, 1934;U, 1935).…”