Nursery germination trial of Tali seeds, Erythrophleum suaveolens (Guill. & Perr.) Brenan

Abstract

The current low recruitment rate of the exploitable tree species arouses silvicultural interventions for long-term management of their populations. This study evaluated the germination of the Erythrophleum suaveolens seeds in nursery following different pretreatments. The seeds have been collected under seed trees of E. suaveolens chosen in a range from 30 to 155 cm North Congo in the Celtis forest within a plot of 400 ha on clay-sandy to sandy-clay soils. A complete design randomized of two blocks has been establish in the greenhouse at respective average temperature and humidity of 24°C and 60%. The seed lot (350 seeds) has been divided into seven treatments for to test the modalities of breaking dormancy, at the rate of 50 seeds per treatment. The dormancy of the collected seeds was lifted by germination tests after treatment with sulfuric acid (H₂SO₄), in an oven at 140°C and in the boiling water. The seeds have been individually and immediately sowed after treatments. The germination rates were 68-76%, 36-56%, 16% and 12-28%, respectively for the T2, T1, T5 and T6 treatments, with germination times of 6 days for T1 and T2, 15 days for T5 and 15-20 days for T6. Treatments T3, T4 and T7 presented zero germination rates. The factors that can influence seeds variations of germination are discussed and recommendations inherent in the considerable efforts of assisted regeneration of this species which occupies a preponderant place in logging in Central Africa are formulated.