
%0 Journal Article
%A Palni, LMS 
%T Cytokinin Accumulation in the Culture Medium of <I>Vinca rosea</I> L. Crown-Gall Tissue: a Time-Course Study
%J Functional Plant Biology
%D 1984/06/01
%V 11
%N 3
%P 129-136
%K 
%R https://doi.org/10.1071/PP9840129
%U https://www.publish.csiro.au/paper/PP9840129 
%X Cytokinin activity was detected in the culture medium of Vinca rosea (Catharanthus roseus (L.) G. Don) crown-gall tumour tissue 1 week after subculture. Activity increased with time, reaching a plateau at 5-6 weeks. The cytokinin activity from extracts of staled culture medium after 1 and 2 weeks culture cochromatographed with zeatin, zeatin riboside and their dihydro derivatives. An additional slow-moving peak of cytokinin glucoside-like activity was observed from 3 weeks after subculture, and was detectable even at the end of a 10-week culture period.    When [U-14C]adenine was supplied to V. rosea crown-gall tissue, analysis of radioactivity remaining in the medium showed incorporation of label into zeatin and zeatin riboside (trans-isomers only) after only 1 h of incubation. Radioactivity in these compounds increased with time; peaking at 8 h, and was still detectable 125 h after incubation. At no time was radioactivity detected in dihydrozeatin, isopentenyladenine or their ribosides. At the end of 125 h incubation, less than 0.2% of radioactivity supplied initially was still present as adenine in the medium.    Significant inhibition of tissue growth occurred when it was cultured on medium supplemented with a synthetic or naturally occumng cytokinin. 
