Water-use efficiency of soybean (Glycine max) using line-source oprinkler technique

Abstract

A field study was conducted with a line-source sprinkler technique during rainy season (kharif) 1995 at Ludhiana
to characterize evapo-transpiration and water-use efficiency  of soybean [Glycine max (L.) Merr.]. Four water-application
treatments (I₁' I₂, I₃ and I₄) with progressively decreasing amounts of irrigation were marked in the direction perpendicular to the line source. The I₁, I₂, I₃ and I₄ treatments received differential irrigation of 187.8, 136.6,
109.1, and 57.9 mm respectively, in addition to season's monsoon rainfall. The cumulative seasonal soil-water use by the crop amounted to 661, 654, 644 and 571 mm for the I1' I2, I3 and I4 treatments respectively. The water-use efficiency of 2.48, 2.46, 2.34 and 2.46 kg/ha/mm for straw yield and 0.826, 0.716, 0.688 and 0.711 kg/ha/mm for seed yield was obtained under the I₁, I₂, I₃ and I₄ treatments respectively. A linear relationship between water use and dry-matter production existed for various treatments. Dry-matter production and seed yield were maximum in I₁ followed by I₂, I₃ and I₄ treatments (in the decreasing order).