Enhancing the growth,photosynthetic capacity and artemisinin content in Artemisia annua L. by irradiated sodium alginate

Degrading the natural bioactive agents by ionizing radiation and then using them as growth promoting substances is a novel emerging technology to exploit the genetic potential of crops in terms of growth, yield and quality. Polysaccharides, such as sodium alginate, have proven to be wonderful growth promoting substances in their depolymerized form for various plants. The effect of depolymerized form of sodium alginate, produced by irradiating the latter by ⁶⁰Co gamma rays, was studied on Artemisia annua L. with regard to growth attributes, physiological and biochemical parameters and artemisinin content. The study revealed that the irradiated sodium alginate (ISA), applied as leaf-sprays at a concentration of 20–120 mg L^?1, improved the growth attributes, photosynthetic capability, enzyme activities and artemisinin content of the plant significantly. Application of ISA at 80 mg L^?1 increased the values of the attributes studied to the maximum extent. The enhancement of leaf-artemisinin content was ascribed to the ISA-enhanced H₂O₂ content in the leaves.