FERNÁNDEZ C. E., VIEHMANNOVÁ I., BECHYNÌ M., LACHMAN J., MILELLA L., MARTELLI G.
Abstract
Yacon (Smallanthus sonchifolius), a native plant of the Andes, belongs to the family Asteraceae. Four genotypes of yacon obtained from Germany, New Zealand, Ecuador and Bolivia were cultivating on the trial fields of The Institute of Tropics and Subtropics of CUA during 2001-2004. During this period the growth and development of plants were studied. On the basis of knowledge of morphology and the dynamics of plant development a macrophenological scale (according to BBCH scale) was elaborated, which collects ten principal growth stages: 0 Sprouting, 1 Leaf development, 2 Ramification, 3 Crop cover, 4 Formation of tuberous roots, 5 Bud formation, 6 Flowering, 7 Formation of achenes, 8 Maturity of achenes, 9
Senescence. Prior to reaching full maturity of tuberous roots the vegetation is finished as a result of the coming of early autumn frosts. The elaboration of a phenological scale could help to contribute to the optimal cultivation method and the dates of agrotechnical interventions in field conditions during the vegetation period. Cultivation of yacon in Czech Republic showed that this crop could be successfully cultivated in the conditions of Central Europe. The length of the vegetation period is the only limiting factor, because it is restricted by spring and autumn frosts.
Key words:
yacon, Smallanthus sonchifolius, BBCH scale, phenology, vegetation period.