Abstract
The results of this study achieved during the year season 2010 , at Mosul city and the results showed that the aphids were appeared on almond trees at the 1st week of March in a small number and the aphid population reached its peak at the 1st week of April and reached 3482 ( Adults and Nymphs ) per sample at 22.2 º C and 60% R.H. The results also revealed that the Aphid preferred the South and East direction of the almond tree . The regression equation relationships between Aphid number and biotic and abiotic factors exhibit a clear effect on Aphid population especially the predators , and the effect of this factor reached 79.5% followed by (69.3 and 66.2)% for the atmosphere pressure and Relative humidity respectively .