Optimizing nitrogen and sulphur nutrition for enhanced yield and yield-attributing traits in groundnut (Arachis hypogaea L.)

Optimizing nutrient management is pivotal for the proper growth and development of plants to ensure higher productivity. The present study evaluated the effect of different nitrogen-sulphur levels on the growth and yield of groundnut. The experiment comprised six N-S treatment combinations (F1-6: N 30, 40 and S 0, 20, 30 kg ha-1) with a control (F0: N 0 and S 0 kg ha-1) using Randomized Complete Block Design (RCBD) with three replications. The result demonstrated significant yield improvements of groundnut under N and S applications compared to the control. Notably, Binachinabadam-8 (V2) treated with the highest level of N-S (F6, N 40 and S 30 kg ha-1) demonstrated the best performance, with enhanced plant height (46.67 cm), number of branches plant-1 (8.67), number of pods plant-1 (37.67), weight of pods plant-1 (27.84 g), number of seeds pod-1 (2.10), 100-seed weight (8.67 g), shelling percentage (73.52%), seed yield (1.55 t ha-1), stover yield (3.07 t ha-1), biological yield (5.36 t ha-1) and harvest index (42.66%). Further statistical analyses, such as Pearson correlation analysis, heatmap analysis, and PCA, confirmed trait contributions like number and weight of pods plant-1, shelling percentage, 100-seed weight, plant height, and number of branches plant-1 for yield variation. The cultivation of Binachinabadam-8 with 40 kg N ha-1 (≈87 kg Urea ha-1) and 30 kg S ha-1 (≈167 kg Gypsum ha-1) might offer a promising strategy towards groundnut productivity. The study provides valuable insights for developing nutrient management strategies aimed at sustainable groundnut production in less nutrient soils.