Pea seedlings were studied to see how calcium affects their response to salt stress. The researchers used different methods to apply calcium and salt stress to the plants. They found that adding calcium increased the activity of certain enzymes in the seedlings, as well as the levels of protective substances like proline and soluble sugar. This helped the seedlings cope better with salt stress, reducing damage to their cells. Watering the roots with calcium was more effective than soaking the seeds, and the best concentration of calcium was 14 mmol/L. Overall, calcium treatment improved the ability of pea seedlings to withstand salt stress.