VEGETATIVE PROPAGATION OF Scyphiphora hydrophyllacea GAERTN F. FOR CONSERVATION

Abstract

Scyphiphora hydrophyllacea is a highly threatened true mangrove confined to Jaffna and asingle locality in private land in Kalpitiya, Sri Lanka. It produces fruits and seeds, butseedlings and young plants are absent in the natural habitat. Conservation has becomeessential and urgent to prevent local extinction of the species. Seed germination usingmoist filler paper method with habitat water varying from 0% - 100% concentration totallyfailed in a previous study. This investigation therefore, aims at the possibility ofpropagating S hydrophyllacea by vegetative means viz. stem cuttings, girdle cuttings andair layering. Stem cuttings of three stages of maturity (first 5 nodes, 6-9 nodes, 1O-l3nodes) were used. Distilled water, water from natural habitat and its 75%, 50% to and 25%dilutions with and without lAA arid activated charcoal (0.25g/100ml) were tested forrooting. Further, dipping of the cut base of the cuttings in commercial rooting powdersnamely Secto containing NAA, Seridox and Clonex both containing IBA and differentconcentrations ofIAA (0.5mgll -2.0mg/l) prior to leaving for rooting was also carried out.Air layering was done by enclosing one-month-old girdles in moist rooting media (threedifferent mixtures and habitat soil). After one month 50ml of half strength Hoglandsolution was injected to the medium. Another set of layers were treated by applying a pasteof Secto on the trimmed edge of the girdle, mixing the same powder with the rootingmedium and injecting IAA to the root ball after one month. Rooted cuttings, girdles andlayers were transferred to soil substrate in pots and maintained under green houseconditions. Rooting was observed only in distilled water in both stem and girdle cuttings.There was no significant effect by exogenous IAA and commercial rooting powders.Charcoal improved rooting from girdle cuttings up to 75%. Stage 11 (6-9 nodes from theapex) cuttings gave highest percentage (40%) of rooting. A maximum of 60% of layers hadrooted in one month. Use of IAA and rooting powder did not improve the rootingpercentage in layers. The plantlets obtained are established in pots in the green houseunder natural temperature and light. The results satisfactorily show that S. hydrophyllaceacan be vegetatively propagated by using appropriate methods. This is important inconservation, as they do not produce seedlings from seeds. Experiments in hardening of theplantlets to grow in their natural habitat are in progress.