Improving the water use efficiency of sugar beet (Beta vulgaris L.) by vermicompost and phytoprotectants

The aim of the present study was to investigate the interaction effects of vermicompost and phytoprotectants on the physiological responses of sugar beet (Beta vulgaris L.) at different levels of irrigation. 

Two-year research was conducted as a split-plot factorial experiment. Treatments were irrigation levels [irrigation at 90% field capacity (extra-watered), 70% field capacity (well-watered), 50% field capacity (moderate stress) and 30% field capacity (severe stress)], vermicompost [0 and 7 t.ha-1] and phytoprotectants [distilled water (control), zinc, silicon, glycine betaine, ascorbic acid].

The results showed that root yield in irrigated plants at 70% of field capacity was higher than other treatments. Also, the yield and dry weight of the roots were significantly increased by the application of phytoprotectants. Phytoprotectants and vermicompost had no effect on water use efficiency of root yield at 70 and 90% of field capacity, but, water use efficiency with glycine betaine at 50% field capacity and with silicon and glycine betaine at 30% field capacity with vermicompost application increased significantly. The effectiveness of glycine betaine for transpiration efficiency and sugar yield was higher than other treatments, regardless of irrigation. The highest root yield was obtained in the treatment of 70% field capacity and was significantly increased by the use of phytoprotectants and vermicompost.

Our findings show that the use of vermicompost and phytoprotectants (especially glycine betaine and ascorbic acid) could be effective in modulating water stress to sugar beet and help to have sustainable agriculture.