DYNAMICS OF THE ACCUMULATION OF FRUCTOSE-CONTAINING CARBOHYDRATES IN THE UN-DERGROUND ORGANS OF PLANTS FROM DIFFERENT FAMILIES

Abstract

Fructose-containing carbohydrates (fructans) are sources of reserve nutrients for plants and ensure their adaptation to stressful environmental influences. We studied variability of content of these compounds during growing season. In species of Dicotyledonous (Echinacea pallida, Tussilago farfara (Asteraceae), Lithospermum officinale, Symphytum officinale (Boraginaceae)) content of glucofructans during the period of active growth was low, a significant part of them were low molecular weight compounds. By the end of growing season polymerization index rised and high molecular weight glucofructans prevailed. The separation in time of processes of intensive growth and accumulation of fructans was observed. For species of Allium (Monocotyledonous), maximum content of glucofructans was observed during the period of flowering and fruiting. In species of bulbous life form (A. caeruleum, A. aflatunense), accumulation of high molecular weight glucofructans proceeded simultaneously with a period of intensive growth and budding, polymerization index increased from the regrowth and reached a maximum by the time of flowering. In species of bulbous-rhizomatous life form (A. obliquum, A. ledebourianum, A. victorialis), content of glucofructans did not change during intensive growth or fell. The polymerization index decreased during this period, but reached its maximum during flowering and fruiting. Generative individuals of a number of species contained less low molecular weight glucofructans than virginal ones, but they had a greater amount of high molecular weight glucofructans and an increased polymerization index. These age states did not differ in the sum of glucofructans.