Soilless Cultivation of Lettuce (Lactuca sativa): Impact of Fertilizers on Growth and Disease Reduction in Burkina Faso

In market gardening, some common agricultural practices pose environmental and health concerns. Indeed, household waste, biomedical waste, sewage sludge and many others are used as fertilizer for production. Also the acidification of soils due to the mineral fertilizers used constitutes real problems. Lettuce is the fourth market garden product cultivated with approximately 8% of the cultivated areas. Its cultivation requires even more attention as it is consumed without any prior cooking. In addition, lettuce is considered one of the species that accumulates heavy metals. It is within this framework that this study takes place, the objective of which is to contribute to the improvement of lettuce production. Four types of fertilizers were used: cow dung, poultry manure, compost and NPK. The methodology used consisted of using disused of 1.5 liter cans, serving as containers. Each can has two openings serving as pockets into which coconut fibers constituting the substrate are introduced. The entire system is installed at a height of 1 m. At maturity, the average agro-morphological parameters measured give the following results: 38 leaves with compost and 35 with NPK, 17 cm and 14.13 cm in height respectively with compost and NPK, 14.13 cm with compost and 12.2 cm with NPK for leaf width, 15.13 cm with compost and 13.40 cm with NPK for leaf length. For total fresh biomass, we obtained an average mass of 156.86 g with compost and 147.2 g with NPK. Compost is the fertilizer best suited to the experimented system, followed by NPK. We did not observe any symptoms of leaf disease, proof that the device can help eradicate infections. Soilless agriculture can be a sustainable solution for food security in addition to other environmentally friendly agricultural systems.