Influence of irrigation scheduling based on IW/CPE ratio on growth and yield of Groundnut (Arachis hypogaea L.) under different sowing dates

Abstract

The impact of irrigation levels based on the IW/CPE ratio on groundnut (Arachis hypogaea L.) growth and yield under various sowing dates was investigated through an experiment. In the experiment, TNAU CO-6 groundnut variety was used. The experiment was conducted at the Kerala Agricultural University’s Instructional Farm in Vellanikkara under a split-plot design with four planting dates viz., November 1^st, November 15th, December 1^st, and December 15th as the main plot treatment and three irrigation levels viz., I₁ = 0.6, I₂ = 0.8, and I₃ = 1.0, as the subplot treatments based on the IW/CPE ratio. The data collected from the field experiment during 2019-2020. The findings demonstrated that all growth characteristics, including plant height, number of leaves, and dry matter accumulation, peaked on November 1^st after planting. The harvest index and shelling percentage for the November 1^st planting were on par to those for the December 1^st planting. One of the three irrigation methods, under irrigation treatment I₃ (IW/CPE ratio of 1.0), was recorded highest plant height, number of leaves, yield, shelling percentage, and harvest index. According to the study, the ideal planting date for groundnut cultivation in Kerala is November 1^st with I₃ level irrigation.