Differential Response of Sunflower Maintainer and Restorer Inbred Lines to Salt Stress

Abstract

In order to identify of salt tolerant sunflower inbred lines a set of 24 inbred lines were evaluated as a randomized block design with three replications in Isfahan and Zabol in 2017. Salt stress was imposed following seedlings establishment 20 days after planting as irrigation with two (fresh water) and 8 ds.m-2 electrical conductivity. According to the results, there were significant differences among locations and also salt treatment for all measured traits except for flowering time and oil content. There were also significant differences among inbred lines for all of the characteristics which could be used a source for improvement of salt tolerance in sunflower. Salt stress had a negative impact on agronomic futures of the inbred lines. Achene and oil yield had suffered more than other traits with 34 and 31% reduction respectively. Phenological traits were affected less than agronomic traits. The inbred lines BGK259 and RGK38 had the highest and lowest achene and oil yield respectively. Three lines BGK259, BGK369 and BGK375 with higher STI expressed as more salt tolerant lines. All 12 maintainer lines had a higher STI than all the 12 restorer lines and were more tolerant. Among the restorers RGK22, RGK15 and RGK2 were more salt tolerant than others. In accordance with STI, TOL and GM indices, principal component analysis differentiated BGK259, BGK369 and BGK375 as the most salt tolerant inbred lines.