Introduction: In Asia and the Mediterranean, eggplant is among the top five lists of important plant products (Ferar et al., 2007). Iran is in the belt of diversity in terms of this product (IPGRI, 1985). In terms of nutritional value, eggplant is one of the healthiest vegetables due to its high content of vitamins, minerals and bioactive compounds for human health (Docimo et al., 2016; Plazas et al., 2014; Raigon et al., 2008.(  Modification method of pure line selection (single plant selection) is a suitable method for modification of native masses of self-propagating plants and is one of the most effective methods for maximum use of germplasm potential and using this method in various autochthonous plants. Also in self-harvesting vegetables, many desirable lines and varieties have been introduced (Kahlo, 1988). In Iran, there are native eggplant populations in different regions, most of which included Chah boland Neishabour, Joubar Mazandaran, Qalami Varamin, Sarkhon Bandar Abbas, Ghasri Dezful, Jahrom, Borazjan, Dastgerd Isfahan, Shendabad, Pablandizd Yazd, Lorestan and Shendabad were collected.
Materials and Methods: In order to evaluate the compatibility and stability of the country's eggplant lines, an experiment was conducted in a randomized complete block design with 3 replications and for 2 years in five regions of the country including Karaj, Neishabour, Minab, Urmia and Varamin. In this project, 8 advanced eggplant lines of the country, including lines N12, N61, Y3, Y9, SH2, SH12, V44 and B29, along with three controls, Long Purple cultivar, Varamin landraces and Neishabour landraces were evaluated in compatibility and stability tests were studied. Marketable yield was weighed and recorded for each plot from the beginning of fruiting to the end of the harvest period. Finally, the total performance for each plot was calculated and the analysis of variance and mean comparisons were performed by Duncan method by SAS software and data stability analysis was performed by AMMI method in Gest software.
Results and Discussion: The results showed that among the tested areas, Neishabour with the average fruit yield of 60.56 t ha^-1 had the highest yield. Significance of place interaction in genotype indicates that different eggplant genotypes in this experiment showed different reactions to different climatic conditions. Some genotypes had better phenotypes in some areas. Often, genotypes belonging to a particular region perform better in that region, which indicates the compatibility of these genotypes with the environmental conditions of those regions. Among the studied lines, Y6 and SH2 lines had the highest fruit yield with an average yield of 55.4 and 54.78 t ha^-1, respectively. These Y6 and SH2 with the average fruit yield of 55.4 and 54.78 t ha^-1, respectively, have the highest yield. The highest fruit yield is related to Y6 line in Karaj region and the lowest fruit yield is related to B29 line in Urmia. Line B29 resulting from the native population of Sarkhon Bandar Abbas has the least compatibility with cold regions. On the other hand, the number of harvest rounds in Urmia is the lowest due to early cold. Therefore, the last yield rank for line B29 in Urmia region seems quite logical. Line B29 resulting from the native population of Sarkhon Bandar Abbas has the least compatibility with cold regions. On the other hand, the number of harvest rounds in Urmia is the lowest due to early cold. Therefore, the last yield rank for line B29 in Urmia region seems quite logical. Genotype SH2 had the highest number of fruits in Neishabour and genotype B29 had the lowest number of fruits in Urmia. Genotype N12 in Neishabour had the highest weight and length of fruit and highest plant height compared to other genotypes. While SH12 genotype in Urmia had the lowest weight, length and diameter of fruit. The Varamin genotype in Neishabour was the earliest and the Y6 genotype in Urmia was the latest. Based on AMMI analysis N12, N61, V44, SH12 and Y3 can be offered for all areas as lines with general stability and average proper yields.
Conclusion: Most of the lines tested in this study are compatible with temperate regions of the country, which in general had better compatibility with these conditions and higher performance in these regions, which could be a reason for higher average yield in Neishabour and Karaj. The only selected genotype from Hormozgan province is line B29, which in Minab region had a higher yield than other regions and had the least compatibility with cold regions. On the other hand, due to being cold and having the lowest number of harvest rounds, Urmia region is in the last rank in terms of average performance. Line Y6 resulting from Pabland massif of Yazd showed the most compatibility with Karaj region.