Effect of triacontanol on the micropropagation of <Emphasis Type="Italic">Costus speciosus</Emphasis> (Koen.) SM. Using rhizome thin sections

Summary The highest percentage of shoot regeneration of Costus speciosus was achieved using thin rhizome sections and triacontanol (TRIA). Factors affecting the rate of shoot multiplication and rooting with TRIA have been investigated. Initiation of shoot buds was observed when rhizome thin sections were cultured on B₅ basal medium supplemented with 5μgl⁻¹ TRIA. Shoots with two to three leaves produced roots when cultured on B₅ basad medium supplemented with 2 μgl⁻¹ TRIA. The well-rooted shoots were hardened and transferred to soil where they showed normal growth and a 100% survival rate was achieved. Results of this study showed that TRIA can be used as an effective growth regulator in the micropropagation and conservation of C. speciosus.