GERMINATIVE ENERGY IN GUAJE (Leucaena leucocephala cv. Cunningham) WITH DIFFERENT METHODS OF SEED SCARIFICATION

Abstract

The germination velocity of guaje (Leucaena leucocephala) after planting should be considered in the reforestation of spaces dedicated to grazing in the intertropical zone of hot climates. In the present study scarification treatments were compared in guaje seeds with the objective of evaluating its effect on germinative energy and germination value. The experimental design was completely randomized, with three replications per treatment, and the experimental units were groups of 100 seeds. The treatments were as follows: 1) without scarification; 2) immersion in water at 80 °C for 3 min (hydrothermal); immersions for 12 h in 3) water at 24 °C; 4) ethylic alcohol of 70 °GL; 5) organic thinner diluent, and 6) hydrogen peroxide diluted to 2 %. The seeds were deposited in a clay loam soil substrate and remained exposed to the weather protected by shade mesh. Total germination was higher with hydrothermal scarification (55%) with respect to the other treatments, except for immersion in water (p > 0.05), but with this treatment the germinative energy and viability was the lowest. Immersion in water presented the highest germinative energy (31.66 %), thus it improved germination velocity of the guaje seeds without affecting their germination value and viability. The hydrothermal scarification stimulated total germination and germination value, but it reduced germination velocity with respect to the other treatments, which showed intermediate values of germinative energy. Scarification with organic diluent caused the lowest value of germination (4 %) and total germination (31 %), respectively. The present study makes it possible to conclude that in guaje seeds scarification by immersion in water at 24 °C for 12 h and in water at 80 °C for 3 min favored total germination, but immersion in water increased germination velocity