BROAD-SENSE HERITABILITY AND PERFORMANCE OF TEN SUGAR BEET VARIETIES FOR GROWTH, YIELD AND JUICE QUALITY UNDER DIFFERENT SOIL SALINITY LEVELS

Soil salinity in Egypt. affects plant production, including sugar beet especially in Al-Fayoum Governorate. Screening for salinity tolerant varieties is one of the most often methods used by breeders of sugar beet. The present investigation was carried out at Al-Fayoum Governorate, (29°17ˋ N; 30°53ˋ E), Egypt, during 2017/2018 and 2018/2019 growing seasons. The objective was to study the effect of saline soil in three locations (villages), namely S 1 , (3.57 dSm -1 ) Monshat Sinnuris, S 2 , (8.6 dSm -1 ) Monshat bani Othman, and S 3 , (11.84 dSm -1 ) Monshat Tantawy, on plant growth, quality and yield traits of ten multigerm sugar beet varieties. The experimental design was a randomized complete blocks with three replications. The results showed that root yield and sugar yield, as well as root dimensions significantly decreased by increasing soil salinity levels as compared with the control treatment. Under severe soil salinity, Florima cultivar was superior in root and sugar yields (13.71 and 1.82 ton/fed.). respectively. On the other hand, Euklid cultivar recorded the least values (11.38 and 1.39 ton/fed), respectively. As for the interaction between soil salinity levels and sugar beet varieties, the highest values for root and sugar yields were recorded by the varieties Florima, Toro, Cleopatra , Tarbelli , which were cultivated under severe soil salinity (11.84 dSm -1 ). The results recommended the above four varieties to be cultivated by farmers under saline soil. These varieties are tolerant to soil salinity and they can produce a stable root and sugar yields in the stressed soil. Heritability of metric traits is of great significance to the breeders as its magnitude indicated the accuracy with which a variety can be recognized by its phenotypic expression and determines the generation in which selection can be profitable. The results showed that five varieties had a salinity susceptibility index (SSI) based on root and sugar yields <1 and were relatively tolerant to salinity stress.