Effect of Seagrass Liquid Extracts on Bell Pepper (Capsicum annuum) Under Salt stress Conditions.

Abstract

Salinity is considered as major environmental challenge that affects crop growth and productivity. This study investigated the application of Haodule univervis seagrass liquid extract on bell pepper (Capsicum annuum L.) under salt stress conditions. The salinity treatments were applied by irrigating bell pepper plants with 0, 50, 100, 150, and 200 mM/l of NaCl with four replications. The bell pepper plants were divided into two groups: one group was sprayed with seagrass extract, and the other group was sprayed with distilled water. The salt treatment was applied at every 10 days interval for only three treatments, and the bell pepper leaves were sprayed about seven days after the salt treatment. The results showed an increase in relative water content (RWC) of salt stressed bell pepper plants sprayed with seagrass extract from 0- 100 mM of NaCl treatment, while RWC decreased at 150 and 200 mM NaCl treatments compared to the control. This indicates stressed bell pepper plants sprayed with seagrass extract had higher RWC than plants sprayed with water at 0-100 mM NaCl treatments. Chlorophyll concentration was decreased dramatically in plants sprayed with water at 50mM of NaCl level. However, chlorophyll concentration increased slightly in plants sprayed with water at 100 mM NaCl level then start declined gradually at 150 mM and 200mM NaCl level. The plants sprayed with seagrass extract showed an increase in chlorophyll concentration at 100 and 150 mM NaCl treatment compared to the control. Fresh weights of plants sprayed with seagrass extract were declined at 50-150 mM NaCl compared to the control. However, the highest dry weights of plants sprayed with seagrass at 100 mM NaCl treatment. In addition, plants sprayed with water did not show variations in fresh and dry weights.