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Increased production of sugar beet under rainfed conditions on saline-sodic soils in the Iranian areas highlights the importance of salt tolerant varieties. Screening of genotypes for salinity tolerance is difficult in field due to heterogeneity of physical and chemical properties of soil. In order to evaluate the salinity tolerance of 21 sugar beet monogerm O-types lines, a pot experiment was conducted using a split plot design. The evaluation of plants was performed using 11 morphological and physiological traits at vegetative growth stage under severe salt stress (∼16 dS m-1) and control (0.3 dS m-1) for 8 weeks. Salinity stress significantly reduced weight related traits. The response of genotypes for total weights and stem weights was very similar under both conditions. But, ranking of O-type lines for root weights under normal and stress condition was different. Indeed, there was high significant genotype × treat interaction for two these traits. Cluster analysis by using STI index of all traits allowed the identification of tolerant, moderate tolerant and sensitive genotypes toward salinity. The four salttolerant genotypes, O-type 9669, O-type 1609, O-type 463-2, and O-type 463-5 identified in this study, could be used in the development of salt-tolerant sugar beet varieties. In the second part of this study in order to assess a simple, rapid, and nondestructive method to estimate chlorophyll content, the chlorophyll meter (SPAD 502) readings were recorded and the relation was determined. Regression analysis indicated that there was a significant linear regression between chlorophyll content and chlorophyll meter and about 74% of changes in chlorophyll meter based on chlorophyll content were predicted.

The most important step in developing of a sugar beet hybrid for target trait is selection of CMS line or single cross. In the present study, 12 progenies derived of 4 sugar beet lines(as female parent) with different level of rhizomania resistant, along with 3 pollinators 27270, 27273 and 27274(as male parent) and parents were evaluated in two locations (Mashhad and Shiraz) with rhizomania infestation in 5×5 latice design with 4 replications. The traits consisted of: Root yield (RY), sugar yield (SY), sugar content (SC), Na, K, N- , white sugar content (WSC), purity (PUR) and molas percent (MS). The data analyzed as factorial model in randomized complete block design. The results of genetic analyses in two locations showed significant differences among parents for all the traits except for K and N-. Variance of hybrid was significant for RY and SY. In Mashhad experiment L3 line and T3 pollinator and in Shiraz experiment L3 and L1 lines and T3 pollinator were selected as superior parents for RY, SY and N- traits. The value of SCA showed that in Mashhad experiment L1×T3, L2×T2, L3×T1 and L4×T1 crosses and in Shiraz experiment L1×T1, L2×T3 and L1×T3 had significant and positive value of SCA for RY and SY. As a total, the results showed that cross between a rhizomania susceptible single cross (L1) with a resistant pollinator (T3) was the best sugar beet hybrid among them.