STEROL COMPOSITION OF NORMAL AND HABITUATED SUGAR-BEET CALLUS (BETA-VULGARIS L ALTISSIMA)

A detailed qualitative and quantitative analysis of the sterol content of normal (auxin and cytokinin requiring) and habituated (auxin and c ytokinin independent) sugarbeet callus (Beta vulgaris L. altissima) wa s made using mass spectrometry with gas chromatography. The total ster ol content of the two lines did not differ significantly. Delta(7)-Ste rols were the most important class of sterols in the two sugarbeet cal lus lines, as in all Chenopodiaceae. Elevated levels of Delta(8)-stero ls were found in the habituated callus. These sterols are considered t o be badly integrated in the membrane of eucaryotic cells. A partial b locking of Delta(8)-Delta(7)-isomerase is hypothesized in the habituat ed cell line.