Critical Limit of Sulphur for Linseed in Vertisol of Central India

Sulphur as an essential secondary element is becoming deficient in soil due to continuous use of sulphur free fertilizers growing high yielding varieties & intensive cropping with high sulphur requiring crops. Sulphur is the fourth major nutrient after nitrogen phosphorus and potassium. At present sulphur deficiency in soils of various Indian states varies from 5 to 83 with a mean of 41%. The deficiency of sulphur in soils of Madhya Pradesh is observed to be in 44 % samples. The critical concentration of a nutrient element in plant or soil refers to a level at or below which plant either develops deficiency symptoms or causes significant or (5-10 %) reduction in its yield as compared to optimum. Soil and plant test methods need to be evaluated for a given soil climate and crop situation in order to enable the laboratories to identify the cases of sulphur deficiency and make practical recommendation for corrective measures.