Exogenous putrescine enhances salt tolerance in Populus nigra × maximowiczii: growth, physiological, and biochemical responses

Exogenous application of putrescine alleviated salt-induced growth inhibition, likely through its role in maintaining osmotic balance and energy metabolism. These findings highlight the potential of exogenous putrescine treatment as a practical strategy to enhance salt tolerance in young poplar trees, with implications for forestry and land reclamation in saline environments.