soil compaction reduces growth of secondary roots, soil aeration and water and mineral uptake by plant, and decreases chlorophyll content as well as root yield and sugar content. hence, the effect of soil compaction on sugar beet yield and sugar content farms determined by penetrometer using 40 plots of 100 m2 in 40 sugar beet field of hamedan, asadabad, malayer and bahar at the depth of 0-80 c...