The results of pollen morphology studies of 9 European Rubus species are presented in this paper (R. apricus, R. armeniacus, R. divaricatus, R. fabrimontanus, R. gracilis, R. hirtus, R. laciniatus, R. nessensis and R. pedemontanus). The examination is made by SEM observation for first time and also by LM. All examined pollen grains are small, isopolar and tricolporate. All grains, except for R. armeniacus and R. gracilis tend to have very long colpi. Equatorial bridges constricted, make the pores unvisible in most of the species. R. apricus, R. armeniacus, R. gracilis and R. pedemontanus have the equatorial bridges stretched therefore the dark whole was only the trace of existing endoaperture. The sculpture of the grain confirms striate pattern and the orientation of the muri indicates the differences between the species; R. pedemontanus and R. fabrimontanus appear to have long, compact muri, parallelly orientated to the colpus; R. nessensis appears muri meandrically orientated, reminiscent of "finger prints" pattern with distinct thickenings in the place of connection and numerous narrow grooves with perforations. R. hirtus appears to have striate-scabrate sculpture because of granular elements (punctae) dispersed between the muri on all over the grain like the internal part of the exine. Shape and size turned out to be a poor criterion for identifying species
The results of pollen morphology of Malesian Rubus species are presented. The pollen samples represented 2 subgenera; 2 species of subgenus Chamaebatus (R. calycinus, R. pectinellus) and 13 species of subgenus Idaeobatus (R. acuminatissimus, R. alpestris, R. archboldianus, R. chrysogaeus, R. copelandii, R. ellipticus, R. ferdinandi-muelleri, R. fraxinifolius, R. niveus, R. lorentzianus, R. macgregorii, R. montis-wilhelmi, R. papuanus). The examination of these species has been made by SEM for the first time and also by LM. Detailed descriptions of the pollen grains are given. As in the majority of Rubus species, pollen grains of both subgenera are isopolar and trizonocolporate. The pollen grains were small for some species of the subgenus Idaeobatus only, medium for both subgenera: Chamaebatus and Idaeobatus. The thickest exine was observed among the species of subgenus Chamaebatus and in R. macgregorii of subgenus Idaeobatus. The ornamentation of the studied pollen has shown a great variability. Except for the typical striate ornamentation of the genus, rugulate (R. archboldianus), striatescabrate (R. lorentzianus) and striate-rugulate (R. macgregorii) ornamentation has been observed. New Guinean morphologically similar pinnate Rubus ferdinandi-muelleri, R. montis-wilhelmi, R. papuanus, have pollen with specific type of striate pattern, which is characterised by relatively high muri with variable thickness and lumina filled with granules. Some of their muri resemble baculae typical only for R. chamaemorus. The pollen morphology analysis leads to the conclusion that Rubus montis-wilhelmi and R. papuanus of subgenus Idaeobatus are the closest related species and morphologically very close to R. ferdinandi-muelleri. Since Focke placed the latter species in section Pungentes of the subgenus Idaeobatus, and the two first species were unknown to him - the authors suggest to include them into this section. Despite of the different origin and various types of leaves R. chrysogaeus, R. acuminatissimus and R. niveus have shown similarities in pollen morphology and are grouped together. On the basis of the same criteria, R. copelandii, R. ellipticus and R. fraxinifolius could have been grouped together, as well as R. alpestris and R. macgregorii. Trifoliolate R. archboldianus and R. lorentzianus have not shown similarities of pollen ornamentation to each other and to the previous mentioned species.
The results of studies on pollen morphology of 6 Malesian Rubus species are presented (R. clementis, R. cordiformis, R. diclinis, R. megacarpus, R. novoguineensis and R. royenii var. ikilimbu). The examination has been made by SEM for the first time and also by LM. Detailed descriptions of the pollen grains are given. The pollen grains are small, isopolar and trizonocolporate. Ornamentation is generally classified as striate, although with some modifications. A striate-reticulate pattern has been observed in only one species (R. cordiformis). A rugulate-striate pattern represents R. novoguineensis. The typical striate patterns differed in form, width and orientation of the muri are observed in R. clementis, R. diclinis, R. megacarpus, R. royenii var. ikilimbu. The tectum perforations are clearly observed in R. clementis, R. diclinis, R. megacarpus, R. royenii var. ikilimbu. The relation between the species has also been disscused. Pollen morphological studies confirmed partly the systematic concept. Rubus megacarpus, R. cordiformis, R. novoguineensis show completely different patterns and can not be regarded as closely related species; Rubus clementis has its own striate pattern, which resembles the pollen morphological type of R. lucens (not included in this study). Rubus diclinis and R. royenii var. ikilimbu have almost the same type of pollen morphology
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