Hatching rates of eggs of 2 strains of An. gambiae in simulated breeding sites using samples of soil substrates and water from vegetable areas of Houeyiho and Parakou. 1. Control: CREC-water. 2. Superficial soil from ridges in vegetable areas + CREC- water. 3. Superficial soil in between ridges in vegetable areas + CREC- water. 4. Soil from watering pools + Water from watering pools. 5. Soil from watering pools + CREC-water. 6. Water from watering pools alone. 7. Big water pool found exclusively at Parakou farm. n : number of eggs inoculated in each simultation.