Effect of heavy metals on in vitro growth and development of the Momordica cymbalaria Fenzl

Heavy metals have played a great role in the genesis of the present-day civilization. Human beings are affected when these metals are added to the food chain. Although these are the most important plant nutrients, they are phytotoxic at high concentrations. Heavy metals at super optimal concentrations affect different metabolic pathways in plants and result in their ceased growth and development. They may enter plants either by their root system or through foliar uptake; stunted growth, chlorosis, necrosis, and reddish-brown discoloration are visible symptoms of severe metallic phytotoxicity. The study of heavy metal stress tolerance on Momordica cymbalaria shows the effect on the plant growth and metabolism. All heavy metals treated with high concentrations affect the overall plant growth. The Murashige and Skoog (MS) basal medium with ZnSO4 at 100 mu M concentration resulted in healthy shoot development (9) with a maximum shoot length of 7.2 cm. MS basal medium with low concentration of CuSO4 (50 mu M) achieved a maximum shoot number (7) with healthy leaves and shoots. MS basal medium with higher concentration of CdCl2 (150 mu M) affects plant growth and reduced the regeneration capability completely.