PECULIARITIES OF THE ACCUMULATION OF GLUCOFRUCTANS IN THE ABOVE-GROUND PART OF THE SPECIES OF THE GENUS ALLIUM (AMARYLLIDACEAE)

Abstract

The specifics of the accumulation of fructose-containing carbohydrates (glucofructans) in the above-ground parts of Allium L. species were studied. High molecular weight glucofructans (polyfructans) were present in significant amounts (6.9–10.1%) during the spring regrowth period in the leaves of A. jesdianum Boiss. & Buhse and A. victorialis L. During active growth and budding, their content dropped sharply (up to 0–3.6%). In A. victorialis, at the end of the growing season, the amount of polyfructans in the leaves of the second generation increased markedly (up to 9.7–11.8%). Since the leaves of this species are preserved under the snow all winter, fructans, probably, have a protective function, increasing their resistance to low temperatures.
 In all the studied species, polyfructans were accumulated in the underground part in much greater quantities than in the leaves, except for A. victorialis, where their content in the aboveground and underground parts was similar in the same phenophases, or in the leaves they were contained in larger quantities.
 The content of low molecular weight glucofructans (oligofructans) in leaves at the beginning of the growing season varied from 2.9 to 11.7% in different species. During the period of active growth and budding their content increased significantly up to 4.6–18.9%. The leaves of A. aflatunense B. Fedtsch., A. jesdianum, A. hollandicum R.M. Fritsch, A. rosenbachianum Regel, belonging to the subgenus Melanocrommyum (Webb & Berthel.) Rouy, and A. victorialis, belonging to the subgenus Anguinum (G.Don ex W.D.J.Koch) N.Friesen, are the richest in oligofructans. In A. obliguum L. and A. saxatile M. Bieb., belonging to the subgenus Polyprason Radić, the content of oligofructans in the leaves was significantly lower than in the previous species.
 Considerable amounts of fructans were accumulated in the inflorescences of A. victorialis and A. obliquum.