Physiological Modifications of Growth, Biochemical Compositions and Anti-Oxidant Activities in Water-Stressed Beniseed (Sesamum indicum) as Affected by Glycine Betaine

Water imbalance limits growth and antioxidant production in plants. This study assessed varying concentrations (1, 2, 3 and 4 g/L) of glycine betanine (GB) on growth, nutritional contents, and antioxidant production in beniseed under drought conditions. Plant height (49.40 cm), number of leaves (27), leaf area (231.93 cm2 ), specific leaf area (57.98 m2kg-1 ), and leaf area index (0.62 m2m-2 ) were higher in beniseed treated with 4g/L GB compared with lower concentrations of the osmolyte. However, the well-watered treatment improved significantly the relative growth rate (0.06 mgg-1day-1 ) and net assimilation rate (0.02 gm-2day-1 ). Chlorophyll-a (3.38 mg/g), chlorophyll-b (3.81mg/g) and total chlorophyll (7.20 mg/g) showed a significant increase in the plant under 3g/LGB. Moisture (91.07%), fat (2.74%), ash (3.55%), crude fiber (3.51%), and crude protein (4.47%) were significantly higher (p<0.05) in the treatments grown under 4g/LGB. The observation was consistent in sodium, potassium, calcium and magnesium as well as vitamin A, vitamin B5 and vitamin C. Superoxide dismutase (SOD) (1.58 u/gt), APX (1.18 u/g), CAT (1.58 mg-1 ), GR (1.59 u/g), GST (14.07 mg-1 ) and SP (19.06 u/ml) were higher in the roots of beniseed grown under drought. Conclusively, beniseed grown under,3 and 4g/L GB improved growth attributes and nutritional contents while high antioxidant production was observed in the roots of beniseed droughted compared with other parts.