Abstract

                                Field experiments were conducted at Agricultural College and Research Institute, Tamil Nadu Agricultural University, Coimbatore, from July 2006 to August 2007 to study the effect of varying irrigation regimes and fertilizer levels in maize based cropping system. The experiment was laid out in split plot design with three replications. The experiment consisted of three irrigation regimes in main plots viz., I1 - Drip irrigation at 75 % WRc (computed water requirement of crop), I2 - Drip irrigation at 100 % WRc, I3 - Drip irrigation at 125 % WRc and four fertilizer levels in sub plots viz., F1 - 75 % RDF, F2 - 100 % RDF, F3 - 125 % RDF and F4 - Drip irrigation + 100 % RDF by soil application. The expenditure incurred from field preparation to harvest was worked out and used for calculating the economics of drip system. The gross income (Rs. 3,09,554) was higher in the treatment with 100 per cent WRc with 125 per cent RDF whereas, higher benefit cost ratio of 4.07 was recorded by drip irrigation at 100 per cent WRc with soil application of RDF. Drip irrigation at 75 per cent WRc with 125 per cent RDF (I1F3) recorded higher net profit per mm of water used (Rs. 274), which was followed by same irrigation regime with 100 per cent RDF.

Key words : Drip fertigation, maize, economics