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Sorbaria species cultivated in Poland

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Specimens of the genus Sorbaria cultivated in Polish dendrological collections have been examined. It appears that in Poland only 3 species are cultivated: S. sorbifolia, S. kirilowii and S. tomentosa. Some supposed hybrids of S. sorbifolia and S. kirilowii or S. tomentosa have been found in the Arboretum in Kórnik and Botanical Gardens in Poznań and Warsaw. A new, supplemented distribution map, a key to identification, and descriptions of the species occurring in Poland are given.
The indumentum of P. alba, P. tremula and their hybrid (P. ×canescens) is discussed in detail and illustrated by scanning electron microscope and light microscope micrographs. Special attention is given to the hairiness of stems and leaves and to the diagnostic value of hairiness in distinguishing the grey poplar from its parent species. Presence or lack of hairs on leaves and stems, their density and their persistence are very useful features in distinguishing the taxa. Short shoot leaves of P. alba are usually described as initially densely white tomentose, but become glabrous or glabrescent. From our observations, it appears that the abaxial leaf surface of the white poplar remains hairy during the whole life span of the leaf. Hairiness does not disappear, but changes with time; arachnoid hairs become squeezed and pressed together until they finally form a very thin shiny layer on the leaf surface. In late summer, the indumentum becomes thinner and leaf blades seem to be glabrous, although hairs are still visible when using a strong magnifying glass. This feature allows easy distinction between P. alba and the similar P. ×canescens, the leaves of which are loosely arachnoid-tomentose when young and become fully glabrous or subglabrous when mature. Due to the presence of arachnoid hairs, the grey poplar can usually also be distinguished from its second parent, P. tremula. However, because of the introgression between the poplars, all possible features should be taken into account in diagnosis, especially the shape and indumentum of terminal adult leaves of long shoots and/or stronger suckers. In P. tremula, such leaves are usually broadly ovate, cordate at the base, irregularly serrate, glabrous or hairy, but never with long arachnoid hairs. In P. alba, the upper leaves of long shoots and suckers are deeply lobed, serrate and densely white arachnoid on the abaxial side, while in P. ×canescens they are serrate or shallowly lobed, rather loosely covered with arachnoid hairs and greenish-grey.
The eating disorders have been reviewed based on state-of-art of contemporary psychology, medicine and nutrition science, with a special emphasis put on different symptoms and forms, origins and testing methods. Among promoting eating disorders, bulimia nervosa, binge eating disorder, night eating disorder, sleep-related eating disorder are among offi cially approved and investigated. Among disorders resulting from lack of acceptance of own appearance, anorexia nervosa and bigorexia nervosa are the most serious improper ones. Disorders arising from health care include orthorexia nervosa and recently pregorexia. Different origins of eating disorders are considered, divided into three groups: social, psychological and pathological. The desire to possess a slim shapely silhouette and young appearance, usually under pressure of a social group, may result in disorders such as anorexia nervosa, pregorexia, ageorexia, and bigorexia nervosa. On the other hand, the focusing on eating mainly the biologically pure food, being a purely psychological and individual problem, may be a source of orthorexia nervosa. Majority of disorders have a psychological background constituting the escape and an answer to everyday life problems diffi cult to overcome. Recently, pathology is often considered as an additional and important determinant, which may cause or enhance the appearance of binge eating or night eating disorder. The eating disorders, if not subject to proper therapy and advising, can tend to incline and develop. The further research in order to properly recognise the eating disorders, and fi nd their roots, is necessary at a strict cooperation of psychologists, physicians and nutritionists or dietetics.
Leaf epicuticular wax morphology and chemical composition of total cuticular waxes were studied in two Salix species (Salix alba and S.fragilis) and their hybrid (S. x rubens). A smooth wax layer with small, scattered wax structures covered the adaxial leaf surface in all three taxa, and a crustlike wax layer composed of terminally fused wax filaments was present on the abaxial surface. The leaf cuticular waxes, both epicuticular and intracuticular, were obtained by hot extraction in chloroform and then analyzed by gas chromatography and mass spectrometry. The principal components of the waxes were primary alcohols, fatty acids, aldehydes, n-alkanes and wax esters. The qualitative composition of the waxes was quite similar but there were quantitative differences between the taxa. The epicuticular crystalline waxes are composed of very-long-chain aldehyde polymers.
Results of anatomical studies on the developing pericarp of selected wild roses are presented. Using SEM and CLSM, the changes in the pericarp structure of 5 species have been observed during its formation, from the flowering stage to fully ripe achenes. In the morphological development of the pericarp of Rosa species two main phases can be distinguished: the phase of intensive growth of the pericarp during which the fruit achieves its final shape and volume, and the subsequent phase of pericarp ripening when no significant morphological changes in the pericarp occur. Similarly, in the process of the anatomical development of the pericarp two phases are noticeable, however, during both stages, great internal changes proceed in the fruit. The first phase consists of intensive cell divisions and enlargement, gradual thickening of cell walls and formation of all pericarp layers. Due to these changes, the pericarp achieves its final anatomical structure. The second phase, involving the pericarp ripening, is manifested in the modification of cell walls, mainly by their quick thickening, but first of all by their lignification. The lignification of pericarp cell walls begins in the inner endocarp; it proceeds in the outer endocarp, later in mesocarp and finishes in the hypodermal cells of the exocarp. The epidermal cells remain alive the longest and their walls do not (or hardly) become lignified. The death of all cells finishes the pericarp ripening.
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