Pastos y Forrajes
versión ISSN 0864-0394
A trial was conducted with seeds of Leucaena spp accessions harvested on acid soil and stored under ambient conditions, in order to determine the period and intensity of dormancy and its breaking. For that purpose a simple classification design and four replications were used, with the following treatments: 1) untreated seed (control); 2) coat cut; and 3) water at 80ºC for 2 minutes. In each one of the accessions there were significant differences among the applied treatments and the highest germination values were found with the seed coat cut. All the accessions showed dormant state (between 10 and 98%), which was observed in the germination of the control and the viability with the seed coat cut. The highest dormancy values in the seeds harvested in 2006 were detected in L. macrophylla CIAT 17233, L. macrophylla CIAT 17231, L. diversifolia CIAT 17270 and L. leucocephala IH-1140, which hardness was 98,0; 97,0; 80,0 and 74,7%, respectively; in the seeds harvested in 2003 and 2004, the hardness percentages were 89,0; 69,0 and 60,0% for L. lanceolata CIAT 17252, L. macrophylla CIAT 17238 and L. leucocephala cv. K-67, respectively. The seeds of the accessions were concluded to show postharvest dormancy, which varied between 10 and 98%. In addition, thermal scarification caused dormancy breaking, for which the application of this procedure before planting to Leucaena spp seeds harvested on acid soil in Cascajal, is recommended.
Palabras llave : Germination; Leucaena spp; seed treatment; storage.