Potential of Different Nitrification Inhibitors on Growth of Late Sown Cauliflower Var. Pusa Snowball K-1 and Behavior of Soil NH4+ and NO3- in Typic Eutrochrept Under Mid Hills of NW Himalayas

Abstract

ABSTRACT Towering losses of applied N in the region lead this study to identify the best potent nitrification inhibitors in late sown cauliflower (Pusa Snowball K-1), which could be easily available and eco-friendly. A field experiment was conducted for two consecutive years (2018–19 & 2019–20) with different inhibitors doses supplemented with NPK fertilizer and farmyard manure in CRBD with 3 replications. Results showed that application of recommended dose of fertilizer [N, P & K (125:76:72 kg ha-1)] with inhibitor neem cake (20 g/kg soil) +FYM (250 q/ha) recorded highest nitrogen uptake (92 & 98.9 kg ha-1) for both years, results were comparable to CaC2 treatment (89.4 & 94.7 kg ha-1). Highest nitrogen content in cauliflower with values 7.52 and 7.65%, plant height of 68.43 and 68.90 cm was observed with NPK+ neem cake @20 g/kg soil with statistical significance among all. Regarding growth, increased polar (14.51 & 16.08 cm) and equatorial diameter (17.95 & 18.21 cm) with highest leaf count of 21.42 & 21.96 in 2018–19 & 19–20, respectively were recorded under neem cake. Besides neem cake, melia @ 20 g/kg soil improved growth and lowered the levels of soil nitrate i.e. 42.93 and 40.31 kg/ha where highest i.e. 55.61&51.29 kg/ha were recorded in Pomegranate rind @10 g/kg soil and proved a better inhibitor. Nitrate levels have been decreased in 2019–20 as compared to 2018–19. Therefore, two years of open field research identified neem cake and melia as prominent and potent nitrification inhibitors for cauliflower under mid hilly conditions.