Sensitivity of 24 sugar beet cultivars to water deficit during emergence

Abstract

The aim of this study was to evaluate, in 3 experiments, seedling emergence and sensitivity to temporary soil water deficit in 24 sugar beet cultivars. Seeds were sown in 2012 and 2013 in containers (60x40x15 cm) filled with a soil classified as Luvisol (with 65% field water capacity) and placed in an phytotron. For 2 weeks, until the first counting of seedlings, the temperature was maintained at 10°C, and then it was raised to 15°C to simulate the temperature increase occurring in the spring period in the field. At the first stage of the study, the number of emerged seedlings was counted 14 and 21 days after sowing. After the following 2 weeks, in the second pair of leaves unfolded stage, the plants were not watered for 6 days to evaluate on day 7 their sensitivity to soil moisture deficit. The above cycle was repeated, and the plants were not supplied with water over a period of 6 successive days. At the end of that period, the seedlings were counted, and the ratio of surviving seedlings to the number of seedlings before the first water deficit was calculated again. Under controlled conditions, high emergence capacity (14 days after sowing) was noted in cv. Janosik, Julietta, and Silvetta, whereas very high final emergence capacity (21 days after sowing) was observed in cv. Agent and Julietta. Sugar beet cv. Huzar, Lukas, and Expert were the least sensitive to soil moisture deficit and they can, therefore, be recommended for cultivation in areas prone to water deficit at the beginning of the growth season. Among the conventional cultivars of sugar beet, there are also cultivars with a low susceptibility to drought that increasingly more often causes problems in regions of intensive production of root crops.

Keywords

• beta vulgaris
• emergence capacity
• seedling survival
• simulated drought