Soil test based targeted yield equations for Ratoon sugarcane in alluvial soils

A field experiment was conducted during 2014-15 for developing STCR based targeted yield equation for ratoon sugarcane at SRS, Vuyyur, Krishna district, Andhra Pradesh. The results indicate that per cent contribution of nutrients from soil (Cs) was 106.70 per cent of available N, 79.2 per cent of available P and 52.48 percent of available K towards the total N, P and K uptake by sugarcane. The nutrient contribution of the soil to sugarcane was relatively higher for N as compared to that by P2O5 and K2O. The per cent contribution from fertilizer nutrients (Cf) towards the total uptake by sugarcane was 22.88, 66.51 and 112.20 per cent, respectively for N, P2O5 and K2O and followed the order of K2O > P2O5> N. The per cent contribution of N, P2O5 and K2O from FYM was 75.76, 20.79 and 49.97 respectively for sugarcane which indicated that relatively higher contribution was recorded for N followed by K2O and P2O5 and the response yardstick recorded was 5.31 kg kg-1.Soil Test based targeted yield equations were developed. These fertilizer prescription equations are transformed into ready reckoner for knowing the fertilizer requirements of N, P, K for different yield targets of Sugarcane (Ratoon) of soils with varying soil test values.