Enhancing Growth and Productivity of Calendula Officinalis L. Plants by Using Zeolite and Bacterial Extract Treatments Under Water Salinity Stress

Pot experiments were carried out at the Experimental Farm of the Faculty of Agriculture, Beni-Suef University, Egypt, during the 2022/2023 and 2023/2024 growing seasons. The study aimed to evaluate the effectiveness of zeolite (Zeo) applied at rates of 0, 10, and 20 g per pot, and bacterial extract (BE) at 0, 5 and 10 ml per pot, in alleviating the detrimental effects of salinity levels (0, 2000, 4000, and 6000 ppm) on growth and yield performance of calendula plants. The findings demonstrated that the higher salinity levels (4000 and 6000 ppm NaCl) markedly suppressed vegetativegrowth and floral attributes. Conversely, the treatments with Zeo at 20 g/pot and BE at 10 ml/pot significantly improved plant growth and flowering characteristics, enhancing the overall tolerance of calendula to salinity stress. Accordingly, the application of 20 g Zeo or 10 ml BE per pot is recommended to enhance the growth and productivity of pot marigold plants grown under saline conditions.