Effect of Foliar Application of Manganese on Plant Growth, Nodulation and Biochemical Attributes of Mungbean (Vigna radiata L.) under Salinity Stress.

Background: Salinity is one of the considerable factors which wanes crop productivity especially in arid and semi-arid realms of the world. The stress created by high soil salinity can cause osmotic stress, specific ion toxicity, nutritional imbalance, hormonal dysfunction and oxidative damage. A study was carried out to determine the effect of manganese (Mn) on growth rate index (GRI), Nodulation status, total nitrogen content, total amino acid content and total protein content of mungbean plants under salinity. Methods: Three indices were used to evaluate the effect of salt stress on development of mungbean plants (100, 200 and 300 mM NaCl). Untreated plants served as control expect. Mn was supplied to the plants in form of manganese chloride (MnCl2). The plant samples were analyzed for 65 days at every 10-day interval. Result: The results revealed that low level of salinity (100 mM NaCl) showed a significant increment in all the above observed parameters, while higher concentrations (200 mM and 300 mM) decreased the mentioned attributes. Foliar spraying with Mn (0.15%) mitigated the deleterious impacts of salinity and enhanced growth, nodulation and biochemical parameters. Thus, foliar treatment with Mn can be used in increasing the tolerance capacity of the plant and to enhance the nitrogen fixing ability of the plant under salinity. [ABSTRACT FROM AUTHOR]