The role of the roots in the life strategy of Colchicum autumnale

FRANKOVA ,L ., CIBIROVA ,K ., BOKA ,K ., GASPARIKOVA ,O . P ISSN 0006-3088. C. autumnale L. has an unusual life-cycle consisting of two growth stages: the first – autumnal stage (September-December) followed by winter season and the second – photosynthetically active one (March-May) leading to senescence (June) and dormancy (Jul-August). Within this cycle the roots exist for determined period. The root system appears first at the end of September (in the middle of flowering) and remains active till May, when the programmed senescence of above-ground part and the final physical destruction of mother corm take place. Our findings showed that these adventitious roots grow out from the root disk of new daughter corm and besides the nutritional function they possess contractional one. In case of seedling, the thick roots were observed on the new cormlet. It seems that thick roots together with well developed protuberance help the cormlet to descent gradually into the soil. Although the root system of both, young and 10–15-year-old (clonal) plants persists for seven months, the major role within the life-strategy of C. autumnale has the mother corm (warehousing and providing of storages) with protuberance (penetration) and two buds for future generation (continuity and vegetative reproduction). The results of the structural and biochemical analyses indicate that the first autumnal stage is accompanied by rapid starch reutilization from the mother corm, supporting new corm and shoot development, flowering and formation of future above-ground part under the soil surface. The storage reserves of the mother corm showed to be the only source of reduced carbon and nitrogen for all those events. The rest of the starch content was completely reallocated from mother to daughter corm till the end of the second, spring stage. In this paper the content of storage polysaccharides and changes in amylolytic activities were determined. The results are discussed in context of the life strategy of this perennial geophyte.