Pollen morphology of Quercus (subgenus Quercus, section Quercus) in Iran and its systematic implication

Abstract

For the first time, pollen morphology of 9 (4 spp. and 5 subspp.) taxa representing lobed leaved oaks of Iran in the family of Fagaceae has been examined and illustrated using light microscopy and scanning electron microscopy of acetolysed material. Detailed pollen morphological characteristics are given for Quercus section. The pollen grains are single, isopolar, radially symmetrical, tricolpate, tricolporoidate or tricolporate. Pollens were studied to show all possible characteristics like shape, size, apertures, wall thickness, etc., with special reference to the specific features of each pollen type such as structural, sculptural and suprasculptural patterns. There is considerable variation in pollen morphology between taxa so that, three types of pollen shape, five types of structural pattern, two types of sculptural pattern, five types of suprasculptural pattern and three types of perfora distribution are defined. Furthermore, the relationship between pollen morphology and taxonomy is discussed. Overall, pollen characters are shown to be a useful and informative tool for assessing taxonomic position within Quercus section in Iran.

Comparative Pollen Morphological Analysis and Its Systematic Implications on Three European Oak (Quercus L., Fagaceae) Species and Their Spontaneous Hybrids

“…This refers, in particular, to a very diverse, among representatives of this genus, exine ornamentation but also to endoaperture types. Also, data regarding perforation numbers are not accurate [ 38 , 43 , 62 ]. Palynologists give different types of exine ornamentation in SEM in different representatives of the Quercus genus.…”

“…Palynologists give different types of exine ornamentation in SEM in different representatives of the Quercus genus. It can be either micro-rugulate, scabrate or scabrate-verrucate with verrucae beset with small, rounded processes [ 36 ], scabrate, microscabrate or microverrucate-scabrate [ 90 ], granulate, scabrate and microgranulate [ 62 ], granulate [ 72 ], verrucate or microverrucate [ 38 ], psilate-verrucate, verrucate, scabrate, scabrate-verrucate and psilate-scabrate [ 43 ] or microverrucate to verrucate, rarely regulate-granulate [ 90 ]. The three study species were either granulate or granulate-verrucate.…”

“…These characters were described for taxonomic purposes in numerous studies using scanning electron microscopy (SEM) [ 17 , 36 – 48 ]. Many researchers maintain, that pollen morphology can be a valuable source of information for Quercus taxonomy [ 17 , 36 – 40 , 43 , 45 , 46 ], whereas others contest the possibility of differentiating species through characteristics of pollen grains, since intraspecific variability may appear to be the same or greater than interspecific differences [ 49 – 52 ].…”

The phenotypic plasticity of of Picea omorika /Panc./Purkyne morphological pollen traits

“…Apart from physiological, morphological traits of pollen are those that directly affect the pollen germination capacity, fertilization and further reproduction and indirectly the growth and development of plants (KIRK, 1993;DE LEONARDIS et al, 1995;FERRAUTO et al, 2015), which makes them extremely important in the controlled selection of high-quality genotypes -pollinator trees. The study of morphological traits of pollen grains is of great importance in the systematics and taxonomy of plants (SHAH et al, 2005;PANAHI et al, 2012;WRONSKA-PILAREK et al, 2016;JIA et al, 2014;SOARES et al, 2017), as well as in the analyses carried out to determine the somatic or gametophytic ploidy level (DE STORME et al, 2013). The study of pollen morphology (its dimensions, surface area, volume, surface structure) is also relevant from the aspect of global climate change (KNIGHT et al, 2005).…”

Pollen viability in Quercus robur L.

“…Oak pollen has been the subject of interest in studies dealing with morphology as part of systematics and hybridization [10][11][12][13][14][15][16] or paleobotany and plant migration and evolution [17][18][19][20][21][22], aerobiology and pollen production [23][24][25][26][27]. Most of these studies deal with pollen at the species level.…”