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How Do Pollen Grains of Convallaria majalis L. Respond to Different Habitat Conditions?
To date, the effect of habitat conditions on the characteristics of pollen has not been extensively investigated; however, it needs to be remembered that it may be highly significant for the quality of their generative reproduction success. It was decided to conduct the analyses on Convallaria majalis as a common species, naturally found in many different forest habitats. Moreover, the investigations covered pollen morphology and for the first time also the variability of pollen grains in this species. The plant material came from 98 natural sites located in Poland, in nine differing forest habitats. In total, 2940 pollen grains were analyzed in terms of five quantitative features (i.e., the length of the longest and shortest polar axesâLA and SA, exine thicknessâEx, the LA/SA and Ex/LA ratios) as well as the following qualitative ones: pollen outline and shape, sulcus type and exine ornamentation. Our studies revealed that the most important pollen characteristics in C. majalis included sulcus type, exine ornamentation, distribution and size of perforations, LA and pollen shape. The study showed the response of pollen to different habitat conditions found in the nine investigated habitats. The Ex/LA ratio and Ex were these pollen characteristics, which exhibited the most marked response to the different habitat conditions. Pollen from two habitats, moist mixed coniferous forest and upland mesic broadleaved forest, exhibited the most distinct characteristics.
The effect of soil physicochemical properties on intraspecific variability of pollen morphology in Staphylea pinnata L.
Pollen morphology and variability of native and alien, including invasive, species of the genus Spiraea L. (Rosaceae) in Poland
The pollen morphology was studied in 25 taxa of the genusSpiraeaL. The aims of this study were to describe the pollen morphology and variability and to determine whether the pollen features of alien, expansive or invasiveSpiraeaspecies differ from those of other taxa. The species ofSpiraeawere analysed for nine quantitative pollen traits as well as the following qualitative traits: the outline, shape and exine ornamentation. In total, 750 pollen grains were measured. Based on the pollen key exine ornamentation features, then individualSpiraeaspecies were distinguished, while the other species formed groups of usually 2â3, up to 8 species. The most important pollen features included length, width and course of grooves and striae, presence or absence of perforations, as well as their number and diameter. The most variable taxa for all the nine biometric traits jointly wereS.Ăbillardii,S.veitchii,S.nipponicaandS.cana. The pollen of the invasiveS.tomentosadiffered from the other taxa studied, unlike the other invasive species (S.douglasiiandS.japonica).
The effect of herbicides on morphological features of pollen grains in Prunus serotina Ehrh. in the context of elimination of this invasive species from European forests
AbstractPrunus serotinaEhrh. is an alien invasive neophyte widespread in European forests. So far, no effective methods of its elimination have been developed. For this reason, the aim of our study was to determine how herbicides affect the morphological characteristics of pollen grains. This knowledge may be crucial to control this invasive species. The current study was carried out in a research area of 2.7 ha located in the Zielonka Forest near PoznaĆ, Poland (N 52°31âČ58.016âł, E 17°05âČ55.588âł). We tested morphological differences among ten features ofP. serotinapollen, based on the samples collected from 15 control trees compared to the 50 trees treated with five different herbicides. In total 1950 pollen grains were measured. We confirmed the adopted hypotheses of long-term herbicide influence onP. serotinapollen. Pollen grains from the control trees had a longer equatorial axis, were more elongated in shape and had the largest range of exine thickness compared to the pollen from the herbicide-treated samples. Exine thickness in the control sample was on average 0.74 ”m, ranging from 0.42 to 1.19 ”m. The average values and the ranges of this trait in the samples treated with herbicides were larger (e.g. average exine thickness was from 0.90 to 0.95 ”m). There were differences in the P/E ranges of variability between the control and herbicide-treated samples. In the control sample the P/E ratio was 1.32â2.04 and elongated forms of pollen shapes prevailed, while in the herbicide-treated samples it ranged from 1.03 to 1.47. The share of deformed pollen grains in the herbicide-treated samples was lower than expected, ranging from 8.7 to 25.3%, while in the control samples it was 6%. Logo and Mustang turned out to be the most effective among the herbicides used in the described research. The two used application methods were found to have an effect on pollen quality.
Pollen Morphological Inter- and Intraspecific Variability in Selected Species of Rubus L. (Rosaceae)
Pollen morphology is one of the important vehicles in resolving some taxonomic problems on the family, genera or species level and has become part of the many disciplines and collaborative approaches in plant systematics and evolution. Palynological studies on the large and taxonomically highly complex genus Rubus L. have been limited, particularly concerning pollen variability. The aim of current study was to investigate the scope of inter- and intraspecific variability of the studied species based on pollen morphology, as well as verify taxonomic usefulness of pollen traits in distinguishing the studied taxa. The sixteen native Poland and Europe Rubus species were studied. Over a dozen quantitative and qualitative features of 2100 pollen (70 samples of 30 pollen each) were analyzed. Exine ornamentation and pollen size proved to be most useful pollen traits in the assessment of variability in the studied Rubus species. Pollen traits did not confirm the currently adopted taxonomical division of the genus Rubus into subgenera, sections and series. The greatest interspecific variability was found for traits P, E, Le and d, while variability was lowest in the case of Exp, Exe, P/E, Le/P, d/E, Exp/P and Exe/E. Intraspecific variability was determined by the following features ordered from those least to most variable: P, E, d, Le, d/E, Exp/P, Exp, P/E and Le/P.