Issues of Petasites spurius (Compositae) biomorphology

The paper describes the shoot formation, structural-functional zone of monocarpic shoot, the basic structural-morphological adaptation Petasites spurius (Retz.) Reichenb. to environmental conditions. The bud, geophilic shoot I, vegetative assimilating shoot, geophilic shoot II, bud-flowering-fruiting and secondary activities phases are marked in the development of the shoot. Monocarpic shoot differentiated into structural-functional zones: lower, middle and a top inhibition, resumption, hidden generative, enrichment and the main inflorescence. As a basic adaptation to environmental conditions at monocarpic shoots marked: fully formed reproductive structures in buds from autumn, early spring flowering, a long growth and polyalternativeness of development, of medium specified fully formed reproductive structures in vegetative-generative buds from autumn, early spring flowering, long monopodial increase, a double change of the growth direction, expansion of the size of the resumption zone.