Potato water use and yield under furrow irrigation

Field experiments were conducted to study the effects of plant-furrow treat ments and levels of irrigation on potato (Solanum tuberosum L.) water use, yield, and water-use efficiency. The experiments were carried out under def icit irrigation conditions in a sandy loam soil of eastern India in the win ter seasons of 1991/92, 1992/93, and 1993/94. Two plant-furrow treatments a nd two levels of irrigation were considered. The two plant-furrow treatment s were F-1 - furrows with single row of planting in each ridge with 45 cm d istance between adjacent ridges, and F-2 - furrows with double rows of plan ting spaced 30 cm apart in each ridge with 60 cm distance between adjacent ridges, The two levels of irrigation (LOI) were I-1 - 0.9 IW/CPE and I-2 - 1.2 IW/ CPE, where IW is irrigation water of 5 cm and CPE is cumulative pan evaporation. Treatment F-2 produced highest tuber yield in all years with average value of 10,610 kg ha(-1) and 12,780 kg ha(-1) at LOI of I-1 and I- 2, respectively. On average, six irrigations with a total of 25 cm, and sev en irrigations with a total of 30 cm were required for both treatments F-1 and F-2 at LOI of I-1 and I-2, respectively. Treatment F-2 resulted in a si gnificantly higher number of branches and tubers per plant, foliage coverag e and water-use efficiency for both irrigation levels than treatment F-1. A verage daily crop evapotranspiration was found to range from 1.1 to 3.4 mm. and from 1.2 to 3.9 mm for treatment F-1 and from 1.1 to 3.6 mm and from 1 .2 to 4.0 mm for treatment F2 at LOI of I-1 and I-2, respectively.