Effect of Long Term Fertilization on PH, EC and Exchangeable CA and MG in Vertisols Under Sorghum-Wheat Cropping Sequence.

The experiment was under taken during the year 2007-08 to study the effect of long term fertilization and manuring on exchangeable Ca and Mg. The soil is calcareous slightly alkaline in reaction, low in OC and available N very low in available P and high in available K. The experiment comprised of twelve treatments including NPK levels with and without FYM, sulphur and zinc replicated four times in randomised block design. The manure and fertilizers were given to sorghum crop every year and only fertilizers were applied to wheat crop. The soil samples from all the treatments were collected from 0-20 cm depth. Highest and significant exchangeable Ca and Mg were noticed in the treatment 100% NPK + 10 t FYM ha-1.