Optimizing Groundnut (Arachis hypogaea L.) Yields: An Effect of Sowing Dates and Planting Densities in India Hot Arid Regions Under a Changing Climate

Abstract

Groundnut (Arachis hypogaea L.) holds immense significance as an oilseed crop on a global scale. The growth and development of plants, along with crop productivity, are substantially impacted by the adverse effects of global climate change. In view of this, a research initiative was undertaken to investigate the effects of distinct sowing dates and planting densities on the yield and economic aspects of groundnut in the hot arid region of Rajasthan, India. The experiment, conducted over a span of three years during the kharif seasons of 2017, 2018, and 2019 at Swami Keshwanand Rajasthan Agricultural University, Bikaner, Rajasthan, India. The experimental design utilized a split-plot layout with four replications, comprising nine treatments. The main plot treatments involved three different sowing dates (15th May, 30th May, and 15th June), while the sub-plot treatments encompassed three planting densities (1.67 lakh, 2.50 lakh, and 3.33 lakh plants per hectare). Notably, the diverse sowing dates and planting densities exhibited notable effects on groundnut yield and economic viability. Comparative analysis revealed that sowing on May 30th, while statistically comparable to June 15th sowing, yielded the highest number of branches, pegs, pods per plant, kernel and pod yield, net return, and benefit-cost ratio. Interestingly, the highest haulm yield per hectare was achieved with the May 15th sowing, yet the harvest index improved progressively as sowing was delayed from May 15th to June 15th. However, the various sowing dates had no discernible effect on kernels per pod, seed index, and shelling percentage. Furthermore, employing a planting density of 1.67 lakh plants per hectare was resulted in the highest counts of branches, pegs, pods, kernels per pod, seed index, and shelling percentage. Remarkably, the elevation in planting density up to 2.50 lakh plants per hectare led to enhanced kernel and pod yields, harvest index, and net return. In an intriguing interaction between sowing dates and plant populations, the most favorable pod yield, kernel yield, and net return were recorded with a planting density of 2.50 lakh plants per hectare for the May 30th sowing. These findings underscore the significant effect of sowing date and planting density on yield attributes and ultimately on groundnut yield in the challenging hot arid region. Therefore, the timing of sowing and the density of planting play pivotal roles in enhancing groundnut productivity within this region, particularly in light of the changing climate conditions.