Study of the effect of salinity stress on quantitative and qualitative characteristics of sugar beet genotypes

Salt stress is one of the most important abiotic stresses, which decreases crop yields and limits the land use. Three hectares of agricultural land are being destroyed in each minute by salinity In Iran, salinity is one of the most important factors which limit the agriculture. Salt stress studies were very important in the most sugar beet planting regions of Iran based on sugar beet experts and farmers opinions producing sugar beet salt tolerant varieties, improving planting methods, irrigation and fertilizer use are the most Sugar Beet Seed Institute (SBSI) strategies for optimizing the production in saline lands.

In order to investigate the effect of salinity stress on quantitative and qualitative characteristics of sugar beet genotypes in normal and salinity stress conditions an experiment was conducted in a completely randomized block design with three replications in Miandoab Agricultural and Natural Resources Research Station at 2016-17 Crop seasons. In this research, 16 sugar beet genotypes were tested under two normal conditions and saline conditions with salinity of 12.1 dS/m. In this research, root yield, sugar content, white sugar content, sugar yield, the amount of sodium, nitrogen, and potassium of root, white sugar yield percent of sugar extraction was measured.Data was analyzed by using SAS 9.2 software.

The results showed that the effect of the environment on all studied traits wasn’t significant. Differences between genotypes were significant for all traits except for white sugar content, also the interaction of genotype in environment on all traits except the white sugar content was significant. Results showed that the highest root yield, white sugar yield and sugar yield in normal and salinity conditions were allocated to genotypes 14 and 15. Based on the results of correlation analysis in both environmental conditions, white sugar yield had positively and significantly correlated with root yield, white sugar content and sugar yield. Based on the results of stepwise regression analysis, root yield, percent of sugar extraction and sugar yield in normal conditions with justified 93 percent of white sugar yield variation and in salt stress condition with justified 84 percent of the total white sugar yield variation were identified as the most effective traits on white sugar yield.

In the present study, there was no significant difference between two years in term of studied traits. It can be concluded that climate conditions in the two years studied did not have a significant difference in terms of effect on the studied traits. In the present study, there wasn’t significant difference between normal and salinity stress conditions in terms of all traits and salinity Therefore, it can be said that sugar beet genotypes were resistant to salinity. In both environmental conditions, genotypes number 14 and 15 had the highest root yield, white sugar yield and sugar yield, Selection of these genotypes is recommended for future breeding programs. In both normal and salinity conditions root yield, percent of sugar extraction and sugar yield recommended as Criteria for selecting high-yielding genotypes.