INFLUENCE OF SELECTED HARVESTER PARAMETERS ON QUANTI-TATIVE AND QUALITATIVE LOSSES OF BREAD WHEAT

Abstract

Two field experiments were conducted on wheat crop in Al-Musayib township Babylon province during the ag-ricultural season of 2011-2012 using Claas combine harvester. The first one was to determine the effect of for-ward speed of 2.4, 3.34, and 4.28 km h-1 and cutting height of 10, 20, and 30 cm on header, threshing cylinder, separation and cleaning, total harvester, and total losses and combine harvester efficiency. A randomized com-plete block design in a split plot arrangement with three replications was used. There is a trend of increase in total harvester losses accompanied by decrease in the efficiency as forward speed increases. Losses in all harvester units decreased whereas the efficiency increased as the cutting height increased. The forward speed of 2.4 km h-1 and cutting height of 30 cm gave the lower total harvester loss of 2.583 % and higher efficiency of 93.824 %. The second experiment was carried out to investigate the effect of forward speed of 2.4, 3.34, and 4.28 km h-1, threshing cylinder rotational speed of 700, 800, and 900 rpm, and cylinder-concave clearance from the front and rear of 12-5 (c1), 17-10 (c2), and 22-15 (c3) mm respectively on kernel damage and germination percentage of wheat grains. A split-split plot arrangement in a randomized complete block design with three replications was used. Results indicated an increase in kernel breakage and a decrease in grain germination due to decrease in forward speed, increase in cylinder rotational speed and decrease in clearance between cylinder and concave. The 4.28 km h-1×c3 interaction gave the least kernel breakage of 5.396 % with the best grain germination of 96.301%. However, the 4.28 km h-1×700 rpm interaction has lower kernel breakage of 5.562 % associated with higher grain germination of 96.913%. Whereas lower kernel breakage of 4.717% accompanied by greater germination of 96.859 % achieved by 700 rpm×c3 interaction.