Effect of GreenSeeker based nitrogen management and its interaction with water on growth and productivity of maize (Zea mays L.) under conservation agriculture

A field experiment was conducted during kharif season of 2019 at research farm of ICAR–Indian Agricultural Research Institute, New Delhi, India, to study the effect of GreenSeeker(GS) based nitrogen management and its interaction with water on growth and productivity of maize (Zea mays L.) var. PMH-1 under conservation agriculture. The experiment was laid out in split-split plot design withtwo crop establishment techniques (CET) viz. conservation agriculture (CA) and conventional tillage (CT) in main plots three irrigation regime (IR) in sub-plotsirrigation at critical growth stages, irrigation at 25% depletion of available soil moisture (DASM) and irrigation at 50% DASM, and four levels of nitrogen (N) in sub-sub plots; no-N applied, 33% N as basal, 33% N at knee high stage and 34% N at silking stage, 50% basal + rest N as guided by Green Seeker (GS) and 75% as basal + rest N as guided by GS. The results showed that GS based N application outperformed over farmers fertilizer practices in terms of growth and productivity, and its interactionalso significantly differed with irrigation scheduling. The maximum value of grain yield (6.9 tha-1), plant height at tasseling (173 cm) and harvest (235 cm), leaf area index at knee high stage (2.11) and silking (4.10), crop growth rate (8.4 and 9.2 gm-2day-1) at 0-30 and 30-60 days after sowing, respectively and NDVI (0.748), were recorded under75% as basal + rest N as guided by GS, over other practices and interaction effect with irrigation at 25% depletion of available soil moisture.