Effect of dormancy on the emergence of Tabernaemontana heterophylla seedlings in different substrates

The composition and dynamics of plant communities are determined by the survival, dispersal and persistence of seeds in the soil, some of the fundamental aspects for understanding plant biology, among which seed dormancy is of particular importance. The aim of this work was to find out whether seed dormancy is affected by certain substrates in order to improve the production of Tabernaemontana heterophylla seedlings. Treatments were carried out with different substrates (T1. Sand, T2. Vegetable clay, T3. Vegetable clay + sand (1:1 ratio), T4. Vermiculite, T5. Cattle manure, T6. Sawdust and T7. Organic compost) in 7 x 4 factorial schemes, the results of which were subjected to an analysis of variance and a comparison of means with the Tukey test at a probability of 5%. The seeds with visible germination structure (hypocotyl) showed an apical meristem in a dormant stage. The number of normal seedlings did not exceed 25% of the germinated seeds in all treatments, with a high proportion of non-viable seeds observed. In the absence of technical information on overcome dormancy, it is important to use strategies that stimulate germination and subsequent seedling growth. The slow germination combined with the presence of dormancy in the hypocotyledon were factors that negatively affected the propagation of the species studied.