Osman Erol

Seed structure and its taxonomic implications for genus Thlaspi sensu lato sections Nomisma , Thlaspi , and Pterotropis (Brassicaceae

* Correspondence: cengiz.karaismailoglu@istanbul.edu.tr

Pollen morphology of some taxa of Thlaspi L. sensu lato (Brassicaceae) from Turkey, and its taxonomical importance

ABSTRACT In this study, the pollen morphology of 22 Turkish taxa (12 of which are endemic) of the taxonomically complex genus Thlaspi L. sensu lato was studied with light microscopy (LM) and scanning electron microscopy (SEM). We found that the pollen of Thlaspi are usually bilateral symmetric and anisopolar. They are prolate, subprolate, perprolate or spheroidal, with the polar axis ranging from 14.13 to 28.36 µm and equatorial axis from 8.75 to 19.48 µm. Pollen are usually tricolpate, but some of them are 1–2- or 4-colpate. The ornamentation of pollen of the examined taxa is usually micro or macro reticulate, and rarely foveolate. The exine thickness ranges from 1.59 to 2.75 µm, and the intine thickness from 0.54 to 0.94 µm. As a result of this study, some of the pollen characters such as the sizes of pollen and colpus, ornamentation of exine, apocolpidium, and shape and diameter of amb are found to be significant morphological characters for taxonomic use.

Phylogeny of the saffron-crocus species group, Crocus series Crocus (Iridaceae)

Phylogenetic relationships among the taxa of Crocus series Crocus are still unclear, preventing the understanding of species diversity and the evolution of the important spice saffron (Crocus sativus). Therefore, we analyzed sequences of two chloroplast (trnL-trnF, matK-trnK) and three nuclear (TOPO6, ribosomal DNA ETS and ITS) marker regions to infer phylogenetic relationships among all species belonging to series Crocus. Our phylogenetic analyses resolved the relationships among all taxa of the series. Crocus hadriaticus and the former C. pallasii subspecies appeared polyphyletic. The latter deserve elevating the subspecies to species rank, while for C. hadriaticus a detailed study of species boundaries is necessary. Multi-locus and also genome-wide single nucleotide polymorphism data obtained through genotyping-by-sequencing placed C. sativus within C. cartwrightianus with no indication that other Crocus species contributed to the evolution of the triploid. Our analyses thus made an autotriploid origin of C. sativus from C. cartwrightianus very likely.