A field experiment was conducted at Tamil Nadu Rice Research Institute (TRRI), Tamil Nadu Agricultural University, Aduthurai to standardize lateral spacing, plant row spacing, fertilizer levels and source of fertilizers on the productivity of hybrid rice under drip irrigation. The experiment was conducted in strip plot design with replicated thrice. Main plot treatments were two lateral spacing (80 and 100 cm) with two plant row spacing (uniform row spacing and modified row spacing). In 80 cm lateral spacing, uniform row spacing of 20 × 10 cm and modified row spacing of 7.5 × 20 × 25 × 20 × 7.5 cm were adopted. In case of 100 cm lateral spacing, uniform row spacing of 20 × 10 cm and modified row spacing of 7.5 × 15×15×25×15×15×7.5cm were adopted. In sub plots, combination of two fertilizer levels (75 and 100% RDF) and two sources of fertilizers (common fertilizers – urea, single super phosphate and muriate of potash and water soluble fertilizers – urea, mono ammonium phosphate and sulphate of potash) were used for fertigation. Short duration hybrid CORH 3 was used.

Results revealed that lateral spacing at 80 cm with modified row spacing (7.5 × 20 × 25 × 20 × 7.5 cm) produced significantly taller plants (76.1 cm), more number of leaves per hill (74.9/hill) and tillers population (625 per m2), higher root growth parameters at maximum tillering stage viz., root length (18.5 cm), root volume (13.1cc) and root dry weight (6.2g), higher yield attributes like productive tillers (453/m2), number of filled grains per panicle(124.9) and higher grain yield of 5055 kg/ha than lateral spacing of 100 cm with modified row spacing. Fertigation with different levels and sources of fertilizers revealed that application of 100 % recommended dose of fertilizers (RDF) as water soluble fertilizer produced significantly higher growth, yield parameters and grain yield of 4230 kg/ha over 75% RDF. However, it was comparable with 100 % RDF as conventional fertilizers.