Soil test based fertilizer recommendation under integrated plant nutrition system for potato (Solanum tuberosum. L) in hilly tracts of Nilgiris district

Soil test based fertilizer prescription equations under Integrated Plant Nutrition System (STCR-IPNS) were developed for potato on Ultisols. Making use of these equations, nomograms were formulated for a range of soil test values and desired yield targets of potato. These equations were validated on farmers’ fields and it was found that the per cent achievement of the targets aimed was more than 90 and STCR - IPNS for 40 t ha−1 recorded relatively higher response ratio (38.05 kg kg−1) and benefit - cost ratio (15.3) over other treatments indicating the validity of the equations for prescribing fertilizer doses for potato.