EFFECT OF ORGANIC FERTILIZER LEVELS AND WATER STRESS ON SOME SOIL PROPERTIES.

Abstract

An experiment was conducted at Horticulture Department Field – Agriculture College – Baghdad university , at silt clay loam soil to study the  effect of the decomposed  organic fertilizer levels  (cow ,sheep ,poultry) manures at percent of (1:1:1:) at levels (0 , 5 and 10) % of  furrow  size.( M0 ,M1 and M2) ,and water stress (550,450 and 350 )mm of  potato requirement  of water ,( S1 ,S2, and S3 ). on aggregate stability and bulk density at maturing  stage of  potato  and on electrical conductivity and soil reaction (pH) ,at tuber initial  and maturing stage of potato . Randomized Complete Block Design was used at three replicates ,potato tubers were sown on 18 December 2012 . Results showed that organic fertilizer levels  , water stress levels and their interactions  increased  aggregate stability and decreased  bulk density significantly at the end of season . All  organic fertilizer levels and water stress levels and their interactions increased electrical conductivity significantly at the two stages of plant growth . while these  factors  decreased  soil  reaction (pH)  at the two stage of  plant  growth