Effect of salinity on growth, proline accumulation and chlorophyll content during vegetative growth, flowering and seed formation of Brassica juncea L.

Abstract

Brassica juncea L (Kraniti) plants were grown in solution cultures having three levels of salinity concentrations (40, 70 and 150 mM w/w)). Higher levels of salinity were achieved by addition of the NaCl, CaCl2 and MgCl2 dissolved in one-fourth strength Hoagland solution. The effect of these treatments on plants growth, proline accumulation and chlorophyll content during vegetative growth, flowering and seed formation were studied. Increasing salinity affected fresh and dry weight of the leaves. These effects were accompanied by a marked increase in the free proline content of the leaves, inflorescences and siliquaes. The rate of accumulation was the greatest, in the leaf, during the period of seed formation. Chlorophyll concentrations in leaves were reduced as a result of increasing salinity, this decrease was greater during the period of seed formation than during vegetative growth and flowering.