From Rabi 1986-87 to KhariJ, 1990, a series of field experiments were conducted in rice tract of North-East levels for Punjab and rice-wheat rotation was followed to study the effect of K fertilization on crop yield. Calculated critical Values ammonium acetate extractable soil study. For rice it was further obs SOIL TEST POTASSIUM AND CROP RESPONSE CALIBRATION UNDER RICE WHEAT CROPPING SYSTEM A/. Akram, R.A. Chaudhry, /.. Ahmad. (i.C. Ilaq, S.J.A. Sherazi and S.M. Mian* ■' • vaiucs II '/'/ K levels were 20(1 and 210 nig kg ! for wheat and rice respectively for all soils under . _ . served that different soil series have their specific soil test K critical limit
