A Study on ABA Induced Changes in Growth and Photosynthetic Pigments of Withania somnifera

Ashwagandha (Withania somnifera L.) is an important medicinal plant; the root is the official part. ABA is the stress hormone, application of ABA cause stress symptoms. Secondary metabolites are increased under stressed condition. Thus, ABA may indirectly improve the medicinal value of the plants. An attempt has been made here to study the growth and photosynthetic pigments of Withania somnifera plants treated with ABA. The plants were raised in the pots. ABA 10-5 M solution was exogenously applied as a foliar spray at vegetative stage. DW was also sprayed as a control of spray treatment. After one month of spray treatment various growth parameters of control and treated plants were noted. The photosynthetic pigments were estimated from the leaf of control and treated plants. ABA spray reduced the root elongation but it was remarkably thick. Root-shoot weight was enhanced by ABA. DW spray increased the elongation of root and shoot but decreased the leaf number. Photosynthetic pigments especially chlorophyll were more in ABA treated plants. Root growth improvement may be correlated with higher amount of photosynthetic pigments. The present data suggest that better root growth in ABA treated plants may increase the medicinal value of plant.