Role of Phosphorous Fertilizers and P Solubilizers on Growth, Yield and Economics of Different Cultivars of Gain Amaranth (Amaranthus hypochodriacus)

A Field experiment was carried out for two years during Kharif season 2018 and 2019 at Main Research Station (MRS), Hebbal, University of Agricultural Sciences, Bangalore. The pooled data of two years indicated that among the varieties, grain yield was significantly higher with Suvarna (1839 kg ha-1) as compared to KBGA-4 (1671 kg ha-1). Among P levels, significantly higher grain yield was recorded with application 30 kg P2O5 ha-1 + PSB @ 2.5 kg ha-1 + VAM @ 2.5 kg-1ha soil application + RD of NK&S (848 kg ha-1) which was on par with RDF (2091 Kg ha-1) and 20 kg P2O5 ha-1 + PSB @ 2.5 kg ha-1 + VAM @ 2.5 kg ha-1 soil application +RD of NK&S (1894 kg ha-1). However, significantly higher yield advantage and agronomic efficiency of P were recorded with application 20 kg P2O5 ha-1 + PSB @ 2.5 kg ha-1 + VAM @ 2.5 kg ha-1 soil application + RD of NK&S (848 kg and 28.26, respectively) which was on par with 30 kg P2O5 ha-1 + PSB @ 2.5 kg/ha + VAM @ 2.5 kg ha-1 soil application (522 kg and 26.12, respectively) and Recommended dose of fertilizer (NPKS). Similarly, plant height and panicle length was followed the same trend. Significantly higher gross returns, net returns and B:C ratio were recorded with application of 30 kg P2O5 ha-1 + PSB @ 2.5 kg ha-1 + VAM @ 2.5 kg ha-1 soil application + RD of NK&S (Rs. 110970 ha-1, Rs.85381 ha-1 and 4.34, respectively) which was on par with RDF (NPKS) and 20 kg P2O5 ha-1 + PSB @ 2.5 kg ha-1 + VAM @ 2.5 kg ha-1 soil application as compared to other treatments. Hence, application of 30 kg P2O5 ha-1 + PSB @ 2.5 kg ha-1 + VAM @ 2.5 kg ha-1 soil application + RD of NK&S is optimum for higher grain yield in grain amaranth.