摘要
This experiment was conducted in silty clay loam soil and cultivated with previous season wheat. Tillage for experiment field was applied using moldboard plow with 0.22-0.24 m depth, the rate of tractor velocity was 2.45 km hf^-1, as a tillage velocity. Two rates of tractor velocities （first factor） were applied： 3.24 km hr^-1, for the first velocity, and 4.71 km hr^-1 for the second, Three types of tillers （second factor） were used： disk harrow, rotavator tiller, and spring spike tooth harrow. The first velocity rate was： 2.51 km hr-l（with disk harrow as a machinery unit）, 2.92 km hr^-1 （with rotivator）, and 3.06 km hrl（with spring spike tooth harrow）, while the second velocity rate was： 3.19 km hr-1 （with disk harrow as a machinery unit）, 4.05 km hrl（with rotivator）, and 4.26 km hrl（with spring spike tooth harrow）. Split plot design in RCBD with three replicates was used at the constant of soil moisture 11%-13%. Results were analyzed statistically and means were tested with LSD. The results showed the significant differences between both two experiment factors and their interaction for all study parameters which included： slippage percentage, practical productivity, numbers of masses 〉 5 cm m^-2, and the implement width. At the constant of pulverization equipment types, the higher percentage of slippage was 16.45%, the higher rate of practical productivity was 0.677 h hr1, and the higher rate of implement width was 2.05 m, while the rate of masses 〉 5 cm m-2 decreased to 13.8 mass m2. At the constant of velocity, disk harrow achieved higher slippage percentage 17.69%, spring spike tooth harrow tiller achieved higher practical productivity 0.858 h hr^-1 and higher rate of implement width 2.73 m, and the rotivator achieved the lower rate of masses 〉 5 cm m2 and 4.1 mass m2. The comparison among the three pulverization equipment typess was the purpose of this study to give the best studied indexes under two different velocities.
