Treatmetns for seed germination in Saccharum Ravennae (L.) Murray and Ziziphus lotus (L.) Lam.

Abstract

Saccharum ravennae (L.) Murray y Ziziphus lotus (L.) Lam. present a series of characteristics which make them potentially useful in the restoration, fixing and maintenance of riverbanks along torrential-type watercourses in the Mediterranean region, as the are well adapted to such environments. Their applicability in vegetation restoration is particularly notable in more arid areas (south-eastern Iberian peninsula). In order for large-scale restoration projects to be undertaken, prior knowledge of the production techniques of a large number of plant species is required. The results of germination experiments carried out in Saccharum Ravennae caryopses and Ziziphus lotus seeds are presented in this paper. The variables used included light (germination under conditions of alternating light and darkness or in total darkness) and substrate type (organic substrate, agar or vermiculite). Several chemical treatments were tested in order to stimulate germination (maceration in hydrogen peroxide, gibberellins and thiourea), and the results compared with those of control experiments macerated in distilled water. The results obtained show that most Saccharum ravennae caryopses have high germination potential, pronounced heliophilia of the caryopses and a slight increase in the germination percentage when agar was the substrate used. The tolerances of germination percentages of all the light/darkness treatments fall within the limits required by the ISTA (International Seed Trial Association) for seed certification. With Ziziphus lotus there was an increase in germination on vermiculite and a slight increase in the germiantion percentage with the thiourea treatment on vermiculite.