Abstract
To establish machine crop factors interrelationships and to evaluate the com-parative performance of John Deere and Claas combines, the present study involved experiments with three speeds of the combines, two wheat varieties (Pak-81, Punjab-85) and three grain moisture levels (26, 20 and 13%). The data collected were analysed to study the variations due to interactions of parameters. Significant interactions occurred for variety-moisture content, variety-machine, moisture con-tent-machine as well as variety-speed. The machine-speed and moisture content-speed interactions appeared to be non-significant. It is suggested that John Deere is beneficial for moisture level of 26% and 20%. The Claas combine can only be em-ployed at 26% grain moisture for minimum losses. John Deere is recommended'at second and third speeds while Claas can only be used at first speed taking into ac-count minimum separation losses. Punjab-85 shows less quality losses compared with its counterpart.