Soil test crop response based Integrated plant nutrition system for desired yield target of preseasonal sugarcane ratoon on Inceptisols
Studies on Soil Test Crop Response based Integrated Plant Nutrition System (STCR - IPNS) were conducted adopting the Inductive cum Targeted yield model onInceptisols (VerticHaplustepts) in Rahuri, District Ahemadnagar, Maharashtra, India in order to develop fertilizer prescriptions through IPNS for the desired yield targets of preseasonal sugarcane ratoon. The field experiments were carried out with maize as gradient crop for plant cane and after harvest of plant cane, pre-seasonal sugarcane ratoon as test crop. Using the data on yield, initial soil test values on available nitrogen (N), phosphorus (P), potassium (K), doses of fertilizers and farmyard manure (FYM) applied and NPK uptake, the basic parameters viz., nutrient requirement, contribution from soil, fertilizers and FYM were computed. It was found that 1.56 kg N, 0.58 kg P and 1.04 kg K were required for producing one tonnemillable cane of preseasonal ratoon sugarcane. The per cent contributions of N, P and K from soil and FYM for preseasonal sugarcane ratoon were 37.65, 85.88 and 19.82 per cent and 11.83, 10.88 and 12.24 per cent, respectively. Making use of these basic parameters, fertilizer prescription equations were developed for pre-seasonal sugarcane ratoon (var. C0-94012) and an estimate of fertilizer doses formulated for a range of soil test values and desired yield targets under NPK alone and IPNS (NPK plus FYM).