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Three problems are discussed in the present article: the currently changing meaning and range of the term "apomixis," opinions on the normality of apomictic processes, and the relation between vegetative and apomictic reproduction. The differences in opinion on these matters reflect the authors’ subjective views, which cannot be avoided in dealing with complex phenomena that are difficult to manipulate experimentally. However, the increase in the number of synonyms that can be observed in the current literature is not useful in discussions and does not make statements easier to interpret. Thus, special attention should be paid to the precise use of terminology in discussions and articles on apomixis and related processes.
The paper reports results of a study on the variability of six morphological features of leaves of Chamaedaphne calyculata (L.) Moench, collected at nine sites in Poland and two abroad. The size of the leaves was found to be strongly dependent on the habitat conditions and was the parameter determining the division into ecophenotypic groups. A linear relation was observed between the length and the width of the leaves.
The research was carried out in the following 9 mesoregions of northem Poland, located on either side of the Vistula: Cassubian Coast, Cassubian Lakeland, Elbląg Plateaux, Górowo Plateaux, Ermelandic Plain, Iława Lakeland, Vistula Delta, Starogard Lakeland and Lower Vistula Valley. Atotal of 11 cropfield-weed communities have been distinguished and described. Those found in cereal crops included: Teesdaleo-Arnoseridetum, Papavereturn argemones, a transition community between Vicietum tetraspermae and Aphano-Matric.:arietum, AphanoMatric.:arietum, Lathyro-Melandrietum and Spergulo-Chrysanthemetum segeti. In root crops the oceurrenee was found of: Digitarietum isc.:haemii, Ec.:hinoc.:hlooSetarietum, Lamio-Veronic.:etum politae, Galinsogo-Setarietum, Fumarietum officinalis and Spergulo-Chrysanthemetum segeti. Due to the presence in the patches of most communities, especially root crop communities, of many common species, they show a number of similarities, floristie and structural.
Anagallis arvensis L. fruits are globose pyxides. They contain a unique globose columella with 20-30 seeds on its surface. In ripe, open fruits the ball-shaped columella detaches easily and becomes a unique diaspore, which can roll on the ground. This way of dissemination has not been described so far neither in Anagallis nor in other Primulaceae.
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