The effect of deficit irrigation on water-yield relationship of sugar beet (Beta vulgaris L.) under cool season and semi-arid climatic conditions

This study investigated the effect of deficit irrigation (0%, 20%, 40%, 60%, 80% and 100% (non-irrigation)) on root, leaf and total sugar yield and water use efficiency of sugar beet (Beta vulgaris L.) under semi-arid and cool season climatic conditions in Turkey. Deficit irrigation treatments significantly decreased root, leaf and total sugar yield compared with the unstressed control (well-irrigated). Root, leaf and total sugar yield of the control were 38.35 t/ha, 12.32 t/ha and 7.34 t/ba, compared with 19.96 t/ha, 5.10 t/ha and 3.84 t/ha in the non-irrigated treatment, respectively. A linear relationship was established between evapotranspiration and root yield. Sugar content in beet was between 18.70% and 19.30%, but there were no statistically significant difference between treatments. The highest water use efficiency was obtained with the non irrigated treatment (91.84 kg/ha/mm). Yield response factor (ky) on root yield was found to be 0.95.