Sugar beet (Beta vulgaris L.) growth at different ploidy levels

The aim of this study was to compare seed germination percentage, seedling growth, total chlorophyll and protein content, sugar content, and root and sugar yields of sugar beet (Beta vulgaris L.) genotypes at different ploidy levels. Sugar beet seeds from cultivars “Agnessa” and “Felicita” (diploids), and lines “AD 440” and “CBM 315” (tetraploids) were obtained from the Sugar Research Institute, Etimesgut, Ankara. Seed germination percentage was recorded after 4 days, whereas seedling and root lengths were noted 4 and 14 days after the study initiation. The size of epidermal cells in length and width were determined on the upper leaf surface of 6-week-old plants. Six and 10 weeks after seed sowing, plant and root lengths, leaf length and width, plant fresh and dry weights, and total chlorophyll and protein content were measured. Data related to yield components such as sugar content, root and sugar yields were obtained from trials conducted by the Sugar Research Institute under field conditions 6 months after study initiation. In the current study, diploid genotypes showed superior responses regarding generative characteristics while tetraploids passed diploid ones vegetatively in the further stages of the development. Ten weeks after study initiation, the highest results regarding vegetative characters such as plant height, root and leaf lengths, leaf width, approximate leaf area, plant fresh and dry weights, and tissue water content were recorded from tetraploid genotypes as 35.00 cm, 43.85 cm, 18.40 cm, 9.25 cm, 170.35 cm ², 369.10 g, 77.45 g and 291.65 g, respectively while the highest total chlorophyll content and protein percentage was obtained from diploid genotypes as 1552.65 μg g –¹ fresh tissue and 21.11%, respectively. The highest values of sugar content, root and sugar yields were obtained from diploid genotypes as 15.55%, 71.47 t ha –¹ and 11.09 t ha –¹, respectively.