Fruit and seed micromorphology of the genus Iberis L. (Brassicaceae) in Turkey and its utility in taxonomic delimitation

Abstract

Background: This paper investigates whether the fruit and seed micromorphology of eight Turkish Iberis (Brassicaceae) species can be used as a further aid in their taxonomic delimitation. Questions: Are the micro-morphological characters of the fruits and seeds of Iberis useful to support the taxonomic delimitation of its species? Studied species / data description /Mathematical model: The eight species of Iberis present in Turkey were examined. The fruit and seed characteristics were obtained and statistical analysis was performed using UPGMA. Study site and dates: Fifteen localities in Turkey, from 2015 to 2019. Methods: Samples of fruit and seed of eight species of Iberis were collected, stored, and later measured and described with aid of light and scanning electron microscopies. Results: All eight species had different fruit and seed characters; particularly differing from each other with respect to fruit and seed size, seed shape and seed ornamentation. Two fruit ornamentation types were evident, smooth and striated. The seed coat surface were separated into three types: reticulate, reticulate-rugose and reticulate-papillate, being reticulate the most common. Further differences were noted for the seed surface epidermal structures, notably species had rectangular, tetragonal, or pentagonal patterning. An identification key was constructed based on a similarity analysis. Conclusions: Fruit morphology, seed dimensions, colour, and epidermal cell patterning are useful microcharacters that enabled species-level determinations in the Iberis species sampled.