ASSESSMENT OF HARVEST AND POST HARVEST GRAIN YIELD LOSSES OF RICE

The present study was carried out in 1999 rice growing season at the six growing Governorates i.e. Kafr EI-Sheikh, EI-Dakahliya, El-Beheira, EI-Gharbiya and Damietta. The main objective of this study was determi­nation of yield losses during harvest and post-harvest processing meth­ods. The yield losses were determined during harvesting, transporting the crop from the field to the threshing yard, threshing and milling. The results indicated that yield losses ranged between 10.33 % to 28.05 of % according to the harvesting and post harvest processing methods used. Moreover, losses during mechanical harvesting were high­er than manual harvesting. Manual harvesting caused the highest losses during transporting the crop from the field to the threshing yard compar­ing with camel or bull-cart methods. The highest losses during threshing were determined for tractor treading method. In addition, the traditional one-pass milling machine (Engelberg type) resulted in the maximum loss­es during milling. Losses were maximized when all traditional harvest and post- har­vest processing methods ( manual harvesting plus transporting the crop from the field to the threshing yard by labor + tractor treading (Korsa) plus one-pass traditional mill) were used, while the lowest losses oc­curred when rice was mechanically harvested and threshed and milled by modern one-pass milling machine.