Studies on Vegetative Propagation of Salacia reticulate (Kothalahimbatu) through Stem Cuttings as Affected by Maturity of Cuttings and Potting Media

Abstract

Medicinal plants could be conserved either through development of improved forms of controlled use and/or through development of cultivation practices. In this context, development of simple, cost effective propagation techniques for threatened species is highly important. Salacia reticulate (Kothalahimbatu) belongs to the family Hippocrateaceae is highly demanded medicinal plant species native to Sri Lanka. Due to over exploitation, the species has now been placed in the IUCN red list. The present investigation studied the effect of maturity of the cuttings and potting media on successful propagation of Kothalahimbatu. The investigation was carried out at the Department of Crop Science, Faculty of Agriculture, University of Ruhuna, Sri Lanka. In the first experiment, soft wood (Tl), semi hard wood (T2) and hard wood (T3) stem cuttings were planted in single plant propagator filled with a potting mixture of top soil and compost (1:1 by volume) to study the effect of maturity stage on rooting of cuttings. In the second experiment, double nodal semi hard wood stem cuttings were planted in black polythene bags filled with different potting mixtures; sand (ti), top soil (t2), sand:top soil (1:1) (t3), sand:coir dust (1:1) (t4), sand:top soil:coir dust (1:1:1) (ts), coir dust (t6), sand:compost (1:1) (t7), top soil:coir dust (1:1) (ts), top soil:compost (1:1) (t^, sand:top soil:compost (1:1:1) (tio) to study the effect of potting media on rooting of semi hard wood stem cuttings. Completely Randomized Design (CRD) was used with three replicates each consisted of thirty stem cuttings. Mean survival percentage at four, eight and twelve weeks after planting was significantly higher (P< 0.05) in soft wood and semi hard wood stem cuttings than hard wood stem cuttings. Furthermore callus formation and emergence of new leaves were also higher in semi hard wood cuttings compared to other cutting types. In the second experiment, top soil:compost (1:1) exhibited significantly higher survival (66.67%) than other potting mixtures. Callus formation of the cuttings was found to be significantly higher (P < 0.05) in top soil:compost (1:1) (t9). Based on the findings, semi hard wood stem cuttings planted in top soil:compost (1:1) could be recommended for vegetative propagation of Kothalahimbatu.