The assessment of quantitative and qualitative yield of different native and foreign sugar beet (Beta vulgaris L.) cultivars under optimal and limited irrigation conditions

This study was conducted to evaluate 18 different native and foreign sugar beet cultivars in terms of some important quantitative and qualitative traits under optimal and limited irrigation conditions in 2017 crop season in as a strip split plot design (normal and stress conditions) as main plots and cultivar factor as sub plots based on RCB design with six replications. The results of combined ANOVA of the obtained data showed that the interaction effect of the environment × cultivar was significant on sugar yield, white sugar yield, alkalinity coefficient, molasses sugar (p≤0.05), and root potassium content (p≤0.01) traits while it had no effect on other traits. Based on the obtained results from ANOVA, the effect of cultivar was not significant on α-amino nitrogen trait while it was significant on other assessed traits under normal condition. Also, under stress condition, the cultivar effect was significant at p≤0.01 on all of the assessed traits. In terms of root yield trait, Merak and Dorthea foreign cultivars had the highest value with 86.5 and 70.4 t ha-1 and Sharif native cultivar had the lowest value with 14.3 and 17.2 t ha-1 under normal and stress conditions, respectively. Under normal and stress conditions, the mean sugar contents were calculated 19.88 and 20.15%, respectively. Although the difference was not significant, the increase in sugar content (about 1.34%) under stress condition was as expected. Given that the decreasing and increasing effects of water deficit stress on most measured traits were not significant, it can be found that sugar beet crop has a good tolerance threshold for water deficit and, surely the finding should always be considered by beet farmers in West Azarbaijan province, especially in the current situation in which there are attempts to revive the drying Urmia lake.