Effect of bio-priming on morphological, physiological and essential oil of Chamomile (Matricaria chamomilla L.) under salinity stress.

• Salinity negatively affected the growth and yield of M. chamomilla. • M. chamomilla seeds bio-priming improved the plant growth under salinity stress. • Bio-priming increased essential oil and chamazulene percentage of M. chamomilla. • Bio-priming is an eco-friendly approach to enhancing plant resilience to salinity. This study aimed to investigate the effect of seeds bio-priming with Nitroxin and bio-superphosphate on some morphological, physiological and biochemical characteristics of Matricaria chamomilla plant irrigated with saline water (0, 2, 4, 6 and 8 dS m −1 NaCl). The findings suggest that the salinity had a notable effect on the growth and yield of M. chamomilla by changing the morpho-physiological and biochemical properties of the plants subjected to stress. However, seeds bio-priming with Nitroxin and bio-superphosphate significantly improved the morphological (increase in plant height by 15 and 13.9 %, number of the flower by 25.7 and 27.9 %, shoot dry weight by 30.2 and 40.2 %, flower dry weight by 50 and 52 %, and harvest index by 11.4, and 9.8 %) physiological (increase in total chlorophyll content by 39 and 41.5 %, water-soluble amounts by 13 and 13.5 %, total phenolic content by 29.5 % and 28.8 %, and decrease in proline content by 10.1 % and 16.6 %) biochemical (an increase in essential oil percentage by 10.9 and 12.8, essential oil yield by 34.5 % and 31 %, and chamazulene percentage by 11 and 15.4 %) characteristics of M. chamomilla at 8 dS m −1salinity, and enhanced the plant's ability to withstand stress as compared to untreated plants. Overall, the findings of this study indicate that bio-priming could be a cost-effective and environmentally sound approach method for improving the growth and yield of M. chamomilla under salinity stress. [ABSTRACT FROM AUTHOR]