Evaluation of the Genotype × Environement Interaction on Agronomic Traits and Seed Yield Stability in Peanut (Arachis hypogaea L.) Genotypes Using the GGE Biplot Method

Extended Abstract Background: The production of peanuts (Arachis hypogaea L.) as one of the vital industrial plants is affected by the environment, genotype, and their interaction. Therefore, the environment × genotype interaction on peanut yield should be evaluated before the introduction of cultivars. Evaluation of the genotype × environment interaction provides valuable information regarding the performance of plant cultivars in different environments. It plays a crucial role in evaluating the stability of the performance of breeding materials. This experiment evaluated the stability and yield of superior peanut genotypes in three regions of Guilan province, Iran, in the 2018 and 2019 crop years. Methods: In this study, the top 10 peanut genotypes (130, 140, 113, 115, 128, 176, 178, 192, 201, and 208 from ICRISAT) along with the NC2 variety as a control were assessed in a complete randomized block design trial with three replications across three regions Rasht, Masal, and Talash. Each plot comprised six lines, each with 5 m long, 50 cm row spacing, and 20 cm plant spacing. Upon reaching physiological ripeness, a 5-m2 area was harvested from the middle four rows of each plot after removing 0.5 m from both ends to eliminate marginal effects. The plant height (cm), average number of sub-branches per plant, number of pods per plant, and number of seeds per pod were randomly recorded and counted from 10 plants. After drying, biomass, pod, and seed yields were calculated in kg/ha. Following seed separation from the shell, five random samples of 100 seeds were taken from each plot to measure the 100 seed weight (HSW). Additionally, the length and width of peanut pods and seeds were recorded (in mm) using a digital caliper. To determine seed oil percentage, 150 g of peanut seeds were randomly selected from each plot, and their oil percentage was measured using the Soxhlet method after grinding the samples. Composite variance analysis was conducted after ensuring the uniformity of experimental error, and the mean traits were compared using the least significant difference (LSD) method. The stability of peanut genotypes was assessed using the GGE bi-plot analysis. Results: The variance analysis revealed that the interaction of location × genotype significantly affected the peanut plant's height, sub-branches, and pod diameter at a one percent probability level. Additionally, the year × location × genotype interaction significantly affected other traits such as po