Studies on Vegetative Propagation of Costus speciosus (Thebu), as Affected by Cutting Type and Potting Mixture

Abstract

Costus speciosus is a herb belongs to order Zingiberales, Family Costaceae, wit a pseudostem and convolete leaf-sheaths. Conventional vegetative propagation of Costus speciosus is carried out through stem cuttings, division of clumps and rhizomes. The study was carried out to select suitable cutting type and potting mixture for propagation of Costus speciosus. Three different cutting types (soft wood, semi hard wood and hard wood) and four different potting mixtures (top soil, top soil:sand (1:1), sand:Compost (1:1) and top soil: sand: compost (1:1:1) were used. The experiment was conducted using Completely Randomized Design with factorial structure and 10 replicates were used for each treatment. Two nodal cuttings were planted in black polythene bags filled with different potting mixtures asinged in different treatments. Data were collected weekly intervals up to four weeks. Number of suckers arising from cuttings and their height, stem circumference and number of leaves per sucker were measured. Cutting type was highly influenced for the success of the propagation. According to the results of analysis of variance, interaction effect of cutting type and potting mixture was significant only on stem thickness (P=0.004). Significantly higher number of suckers was arisen in softwood cuttings (P =0.0011). Height of suckers (P<0.0001) and number of leaves per sucker (P<0.001) also significantly higher in softwood cuttings than other cutting types. But the effect of potting mixture was only significant on height of suckers and significantly higher sucker height was observed in top soil medium (P=0.0084). Results revealed that the best cutting type for propagation of Costus speciosus is soft wood cutting irrespective of different potting mixtures which were not significantly influenced for the propagation.