Response to salinity in black calla lily plant under Mediterranean conditions

Abstract

AbstractHigh soil salinity in arid and semiarid regions results in a reduction in plant growth and productivity. Also, low precipitation is insufficient to cope with high salinity. Black calla lily (Arum palaestinum Boiss.) belongs to Araceae and is used as an ornamental, for food, and in folk medicine. Salinity reduces water and nutrient uptake and causes the accumulation of toxic levels of ions (K and NA) in black calla lily plants. This study was established to evaluate black calla lily salinity tolerance and to determine its tolerance mechanisms. Seedlings of A. palaestinum were transplanted into lysimeter columns. Irrigation treatments included tap water (control) and water with electrical conductivities of 5, 15, and 25 dS m−1. Treatments were continued for 3 mo. Leaf color, leaf area, and plant height were estimated or measured weekly. Samples were collected for total nonstructural carbohydrates (TNC), proline, reducing sugars content (RSC), and tissue K+ and Na+ content analyses. Increasing salinity led to a decrease in leaf characters, TNC, chlorophyll content, plant height, and K+/Na+ ratio, and an increase in proline content and shoot total RSC. The significant positive association between proline content and salinity suggested that proline can enhance osmotic adjustment and act as a N or C source that helps the processes of stress recovery. Dynamics of TNC and RSC indicated that salinity tolerance is an energy‐dependent process. Results indicated that A. palaestinum collected from the Mediterranean area can tolerate irrigation water with a salinity level up to 15 dS m−1.