Validation of soil test and yield target based fertilizer prescription model developed for pearl millet on Inceptisol

摘要

Soil test crop response (STCR) based fertilizer prescription for desired yield target of pearl millet was developed under integrated plant nutrition system (STCR-IPNS) on Periyanaickenpalayam soil series (Vertic Ustropept) of Tamil Nadu, India. The present study was undertaken to validate the developed fertilizer prescription equations (FPEs) through field experiment in Western Zone of Tamil Nadu. The results emanated from the validation experiment proved the validity of the FPEs for pearl millet byrecording the aimed yield targets within±10% variation. Among the treatments, STCR-IPNS-4.0 t/ha of pearl millet has proved its superiority and recorded a yield increase of 59.8, 18.7 and 89.3%, respectively over blanket, blanket plus farm yard manure (FYM) @ 12.5 t/ha and farmer's practice. The increase in response ratio due to STCR-IPNS-4.0 t/ha over blanket, blanket plus FYM@ 12.5 t/ha and farmer's practice was 1.0, 0.9 and 1.5 kg/kg, respectively, and that of benefits : cost ratio was 0.65, 0.28 and 0.79, respectively. Soil test-based fertilization resulted in increased yield, economic returns, protein content, protein yield, and either built-up or sustenance of soil fertility and the magnitude of built-up was higher with STCR-IPNS as compared toSTCR-NPK alone, blanket recommendations, farmer's practice and control.