Oilseeds are one of the most important sources of energy all over the world. Rapeseed is an important crop that its oil has nutritional and high economic value. Rapeseed is one of the most important sources of vegetable oil in the world,
and its seed contains more than 40% of oil, and the meal obtained from oil extraction has more than 35% of protein, and
currently it ranks third among oil plants after soybean and oil palm. in the world. Rapeseed is usually used throughout
the world for food, livestock fodder and industrial applications such as bio-products and biofuel production, biodegrade
able plastics and hydraulic oils. Rapeseed seeds contain protein, minerals, vitamin and oil that are used in nutritional and
pharmaceutical industries [6]. The oleic acid is the most important fatty acid in the oil of rapeseed. The oleic acid has
industrial uses and plays a fundamental role in human nutrition. By using new and high-yield varieties, the economic
performance of this product can be increased. Evaluating of promising advanced lines of soybean under different
environmental conditions is essential in identifying and selecting superior lines with high and stable yield potential.
Genotype × environment interaction effect are important limiting factors in the introduction of new cultivars. The
genotype × environment interaction is a major challenge in the study of quantitative characters because it reduces yield
stability in different environments and also it complicates the interpretation of genetic experiments and makes predictions difficult. Therefore, it is very important to know the type and nature of the interaction effect and reach the
verities that have the least role in creating interaction effects. Various methods have been introduced to evaluate the
interaction effect, each of which examines the nature of the interaction effect from a specific point of view. The
purpose of this study was to investigate the interaction effect of genotype × environment using the parametric, nonparametric and SIIG index methods to identify stable genotypes with high grain yield under different environmental
conditions in rapeseed.