Effect of salinity on germination and seedling growth of 4 sugar beet genotypes (Beta Vulgaris L.)

This experiment was conducted in incubator in other to study the effects of water potential on seed germination, rate of germination and seedlings growth of four sugar beet genotypes named Madison, 7233-P29, 7233-P21 and IC. Four water potential including distilled water as control, -0.37, -0.59 and –0.81 Mpa which made by NaCl and NaCl+CaCl2 in 5 to 1 molar ratio. The experiment was carried out based on completely randomized design with four replications. Results of variance analysis showed that effects of water potential, type of salt composition and cultivar on germination percentage, rate of germination, root and shoot length were significant. With decreasing water potential, germination percentage and rate of germination declined but the response of germination persentage was greater than rate of germination. Cultivars Madison and IC had the highest and the lowest percentage and rate of germination respectively. The effect of salt composition was significant on rate and percentage germination. The percentage of germination at water potential –0.37 which made by NaCl + CaCl2 significantly was higher than the same water potential made by only NaCl. However, at lower water potential (-0.59 and -0.81 Mpa) the rate and percentage of germination significantly were higher at NaCl solution rather than NaCl + CaCl2 solution. When seeds were transferred to unstressed condition, after 20 days of salinity treatment, there was some recovery. Recovery ranged from 27% to 79% germination. This shows that the inhibitory influence of salinity on sugar beet seed germination was mostly due to osmotic effect and a small portion of the inhibition could be attributd specific ionic effect.