EFFECT OF DIFFERENT TILLAGE SYSTEMS ON SOME WATER REQUIREMENTS AND COTTON CROP YIELD

The present investigation was conducted at Sakha Agricultural Research Station , Kafr EL-Sheikh Governorate to study the effect of different seedbed preparation on water requirements and cotton yield. Five treatments were used in this study as follows :A) Disc harrow , B) Chisel plough one-pass + disc harrow , C) Chisel plough two - passes + disc harrow , D) Chisel plough one - pass + subsoiler + disc harrow and E) Chisel plough two – passes + subsoiler + disc harrow . Results showed that the chisel plough was effective in lowering field efficiency to about 65.0 % compared to 92.0% of the subsoiler plough .The slip ratio were the disc harrow about 4.0% compared to 13.06% for subsoiler plough. Generally, the cost of seedbed preparation per fadden was 8.0 L.E/fed for the disc harrow and 23.0 L.E/fed with the subsoiler plough. The yield calculated for each treatment was as follow 4.29,5.17,5.77,6.55 and 6.36 Kantar / fadden for treatments A, B,C,D and E, respectively . Water requirements were 3033, 3185, 3205, 3319 and 3591 m3/fed for the same above-mentioned treatments. Field water use efficiency calculated for each treatment and recorded as follows: 0.22,0.26,0.28,.0.31 and 0.28 Kg / m3 for the same above mentioned treatments. Also, water application efficiency recorded as follows: 73.05,73.63,75.02,74.18 and 70.91%. The soil pulverization degree were 74.6, 73.7, 72.0, 70.4 and 69.0 % for A, B, C, D, and E, respectively.