Abstract
Salinity can negatively affect plant morphology and physiology. The impact of salt stress on plant biomass, total chlorophyll, proline, catalase (CAT), and superoxide dismutase (SOD) was assessed in eight accessions of Sesbania sesban (L.) Merrill, namely Sialkot, Khanewal 1, Chiniot, Bhowana 1, Khanewal 2, Sahianwala, Bhowana 2, and Shahpur. These accessions were grown in pots containing sand and peat moss (3:1). Treated plants were watered with 75, 150, and 200 mM NaCI, and untreated plants (control) were irrigated with tap water. A significant variation was noted in salinity tolerance among the accessions. The proline content and antioxidant enzyme activities increased at 75 and 150 mM and decreased at 200 mM NaCI. Khanewal 2, Bhowana 2, and Shahpur were the best performing accessions, with greater biomass, proline accumulation and higher antioxidant enzyme activities. The Sialkot accession produced the lowest biomass and accumulated less proline with lower antioxidant enzyme activities than the other accessions. Clustering of salt stress responses using Hierarchical Cluster method revealed two major groups: the first comprised more tolerant accessions, and the second comprised moderately tolerant and salt sensitive accessions. Accessions with the highest salt tolerance could be recommended as forge crops in saline areas.