Influence of IBA and Cordycepin on Rooting and RNA Synthesis in Stem Cuttings of Phaseolus aureus Roxb

Adventitious roots are initiated on stem cuttings of Phaseolusaureus Roxb. by treatment with IBA for 24 h, although subsequenttransfer to boric acid is essential for their development. Cordycepinenhances auxin-induced rooting when supplied for 4 h withinthe first twenty hours of IBA treatment, but not thereafter.Cordycepin alone does not enhance rooting. IBA treatment ofcuttings for 12 h results in a marked inhibition of RNA synthesis,including poly(A)-rich RNA, in the hypocotyl. After 24 h treatmentRNA synthesis is seen to increase, with a more marked recoveryin the synthesis of poly(A)+RNA relative to other RNAs. Subsequenttransfer to boric acid maintains this recovery. Cordycepin doesnot inhibit RNA synthesis below the level induced by IBA althoughon subsequent transfer to boric acid is seen to enhance synthesisand turnover of both polyadenylated and non-polyadenylated RNA. (Received August 28, 1982; Accepted November 25, 1982)