Biochemical and yield response of sugar beet to drought stress and foliar application of vermicompost tea

Vermicompost tea (VCT) possess plant growth regulator properties and could play significant role in mitigating drought stress (DS) effects when applied as fertilizer. Current study was planned to assess the effects of VCT levels (0, 27 and 54 L ha(-1)) applications on physiological, biochemical and yield of sugar beet when plants were grown under field conditions with DS (100%, 75% and 50% irrigation water requirement (IWR)). The results showed that severe DS reduced root growth and sugar yield by reducing relative water content (RWC) and chlorophyll contents through increased generation of hydrogen peroxide (H2O2) and malondialdehyde (MDA). However, VCT significantly increased root yield by 20% and sugar yield by 33% under 50% IWR. Vermicompost tea could partly alleviate the effects of DS on sugar beet by up-regulation of the antioxidant system and leaf soluble sugars and simultaneous decreasing of H2O2 and MDA.