Effect of Water on the Growth of Different Types of Propagation Stocks of Lippia multiflora Moldenke (Verbenaceae) Grown on Nursery in Toumodi, Central Region of Côte D'ivoire

Lippia multiflora is used for its therapeutic properties in spite of this it remains a wild plant and therefore runs a risk of extinction which would cause an imbalance of the ecosystem. For the effective domestication of this plant and becoming perennial, a better knowledge of its water needs is necessary. A study of a 5-level hydration treatment of water (I1, I2, I3, I4 and I5) on seeds (roots cutting (S1), stem cuttings (S2) and seeds (S3) of Lippia multiflora in nurseries, was conducted under shade for 2 months. The study aimed at evaluating the growth of this plant in central Côte d'Ivoire, precisely in Blé, 6 km from Toumodi, 180 km from Abidjan. The soil is of Ferralsol type, on a slope. The experimental design was a factorial block in 3 replications. Seed collection was carried out by plowing L. multiflora wild plants. Mature seeds were harvested from the plants. The nurseries were established by seeding in plastic bags. The germinated seedlings were split, one seedling per bag. The water needed was applied manually and by sprinkling every 2 days before 9 am, for 60 DAP. Plant growth parameters (growth and survival rates, number of rejections, plant height, number of leaves produced, and leaf surface area) were assessed using either a meter rule, or numerically.
The results obtained show that the water supply has a significant influence on the growth of Lippia multiflora. The growth was observed for three days after planting (DAP) but this growth was effected between the seventh day and at the 30th DAP, whatever the water application. The seeds (S3) and roots cutting (S1) have a high evolution rate and survival (about 100 p.c.) with well-developed growth in all water intakes. Cuttings are lagging behind others as regard to evolution. Seeds can be ranked according to their death resistance and optimal growth as follows roots cutting (S1) - seeds (S3) - cuttings (S2).

Roots cutting (S1) or seeds (S3) are the main choice for planting Lippia multiflora. Cuttings require further investigation to complement our results. The optimal irrigation doses I3 (50 p.c. UR) and I4 (70 p.c. UR), which are very close to the easily usable soil water reserve (EUR), permit optimal growth for stumps S1 and S3 seeds of L. multiflora.