the evaluation of wheat losses harvesting in two conventional combine (john deere 1165, 955) in iran

wheat is one of the most important food staff in consumption pattern of each country. more than 50 percent of energy is provided by bread in the developing countries. the aim of this study was measuring wheat losses during pre-harvest and harvest stages in chaharmahal and bakhtiari province of iran in year 2013. wheat losses at harvest stages were measured to wheat varieties in 2 levels of omid and alvand were chosen and combine types in 2 levels: jd 955 and jd 1165 while were chosen. the data analyzed using and means were compared using sas software’s and duncan's multiple range tests were. the results showed that higher amount of losses were in the omid variety and jd 955 with totally 6.83 % (307.4 kg ha-1) that 10.5 % of them attributed on the cleaning, 34 % on header, 16.5 % on drum, 21 % on impurity and 18% broken grain losses. the lowest losses related to jd 1165 and alvand variety with 3.97 % (178.66 kg ha-1) that 10 % of them attributed on the cleaning, 38 % on header, 13 % on drum , 22 % on impurity and 17% broken grain losses. also, average pre-harvest losses amount was in all fields the study 24.5 kg ha-1 that 9.8 % of total losses represent the measured total losses alvand 20.5 kg ha-1 and the variety of omid 28.5 kg ha-1 respectively.