In order to design a seeder for direct sowing, a seed characterization study was conducted. The objective was to assess the physical, mechanical and kinetic properties of the most cultivated cereals and leguminous in Benin. Two varieties of Zea mays, four varieties of Vigna unguiculata, one variety of Arachis hypogea, one variety of Cajanus cajan and two varieties of Glycine maxwere studied. It was noticeda variation in physical parameters not only between species but also between varieties of the same species. All sphericity coefficients are greater than 0.7 with C. cajan which is more spherical (0.91±0.03) against the DMR ESR-W/QPM and 85 TZSR-W varieties of Z. mays which are the least spherical with 0.72±0.10 and 0.71±0.11 respectively. The rupture force generally increased from 14 to 720 N. Vigna TVX 32-36 is the most resistant with 633.3±75.72 N against 16.0±2.0 N for Arachis TS32-1 the least resistant. Overall, the falling speed decreased from 1.67 to 0 m/s on the rigid PVC, from 1.36 to 0 m/s on the black plate and from 1.67 to 0 m/s on the transparent hose when the angle of inclination increases from 20° to 70° relative to vertical. These parameters are essential for good sizing of the distribution system and the seed descent channels for a seeder. They can also be used for grains calibration and other use in agricultural engineering and food processing.
Keywords: Seeds, physical properties, mechanical properties, kinetic properties, Benin