Maize (Zea mays L.) is the third most important cereal crops after rice and wheat and is cultivated in a wide range of soil and climatic conditions. Considering the wide range of usage ranged from human nurition to livestock and poultry feed as well as use in industrial products production, maize is considered one of the most important crop plants from agricultural and industrial point of view. Salinity stress limits plants’ growth and development and reduces crops yield.
The response of plants to salinity stress is complex and depends on the concentration of salt, plant growth stage and development, environmental factors and the type of ions. Maize is in the group of relatively sensitive plants to salinity stress and its most sensitive stage is in the seedling phase. Protection of food security is one of the basic priorities of any country, which is achieved through the development and introduction of new, high-yielding and stress-tolerance crop varieties. To improve a trait with complex behavior and low heritability, indirect selection by other traits or developing a suitable index based on several traits can be used. Considering the importance of abiotic stresses, especially salinity in reducing yield, designing an efficient breeding program to increase yield under normal and salinity stress conditions requires the estimation of genetic diversity, detemining the relationship between traits and introducing effective selection indices for seed yield. In this study, while introducing the optimal selection index, genotypes with high performance under normal and salt stress conditions have been introduced; which can be effective in developing promising maize hybrids.