Effect of Crop Geometry and Drip Irrigation on Root Growth, Water Use and Water Use Efficiency of Groundnut (Arachis hypogaea L.)

A field experiment was conducted during Kharif, 2014 at Niche Area Excellence Farm, S K Rajasthan Agricultural University, Bikaner to study the effect of crop geometry and drip irrigation levels on groundnut (Arachis hypogaea L.). The treatments consist of four crop geometry viz. normal sowing (30cm x 10cm) in 90 cm drip line spacing, normal sowing (30cm x 10cm) in 120 cm drip line spacing, paired row sowing in 90 cm drip line spacing and paired row sowing in 120 cm drip line spacing; three levels of drip irrigation (0.6, 0.8 and 1.0 ETc) and compared with surface irrigation at 30cm x10cm crop geometry. The experiment was conducted in randomized block design and replicated thrice. The study of crop geometry levels indicated that highest nodule dry weight (0.245 g), root length (2.61 m plant^{1), root dry weight (2.60 g plant−1), root volume (16.36 cc plant−1) and water use efficiency (3.76 kg ha−1 mm1) of groundnut was recorded with normal sown crop at 90 cm drip line spacing, which was at par with paired row sown crop at 120 cm drip line spacing. The study further indicated that highest nodule dry weight (0.231 g), root length (2.76 m plant−1), root dry weight (2.68 g plant−1) and root volume (16.97 cc plant1) was recorded with drip irrigation level at 1.0 ETc, however, 0.8 and1.0 ETc gave at par values of all these parameters Drip irrigation levels from 0.6 to 1.0 ETc saved water by 254.95 to 41.58 mm over surface irrigation which used 1027.9 mm water. Higher water use efficiency (WUE) of 3.17, 3.73 and 3.43 kg ha−1 mm−1 at 0.6, 0.8 and 1.0 ETc, respectively against 2.69 kg ha−1 mm−1 in surface irrigation.}