Sustaining Soil Fertility and Yield by Inductive cum Targeted Yield Model-based Fertilizer Prescriptions for Finger millet (Eleusine coracana L.) in Alfisols of Tamil Nadu, Southern India

Abstract

Background: Finger millet cultivation in Alfisols (Typic rhodustalf, Palaviduthi soil series) demands an optimal integrated plant nutrient supply to achieve desired yields. In order to develop the soil test crop response to fertilizer and farm yard manure (FYM) through integrated plant nutrition system (STCR-IPNS) in terms of nutrient uptake, yield and pre-sowing STVs, a field investigation on Finger millet [Eleusine coracana (L.) Gaertn.] was conducted at the farmer’s field of Thoppupatti village, Dindigul district, Southern Agro-climatic zone of Tamil Nadu, Southern India during December 2021-August 2022. Methods: By adopting the Inductive cum Targeted Yield Model before the test crop of Finger millet, a artificial soil fertility gradient was created by the application of graded levels of NPK fertilizers with fodder sorghum as a gradient crop. Result: The basic data viz., N, P and K nutrients for producing 1 tonne of finger millet grain were 48 kg, 23 kg and 44 kg; the soil contributed 14.86%, 19.18% and 18.95%; fertilizer contributed 44.16%, 32.79% and 59.75% for N, P and K and farmyard manure (FYM) contributed 28.47%, 11.77% and 33.78%, respectively. Fertilizer prescription equations for finger millet and ready reckoners for the operational range of soil test results for the intended yield target under NPK alone and IPNS (NPK + FYM) were produced using the basic data.