Ali Yousif (1),Ghiath Alloush *(2) and Ahmad Jaloul (1)
(1). Department of Hoticulture- Faculty of Agriculture- Tishreen University, Lattakia, Syria.
(2). Department of Soil and Water Sciences- Faculty of Agriculture- Tishreen University, Lattakia, Syria.
(*Corresponding Author, Dr. Ghiath Ahmad Aloush, E-Mail. galloush@scs-net.org)
Received 9/12/2020 Accepted: 23/03/2021
Abstract:
This study aimed to investigate the tolerance of four tomato hybrid to salinity (Shanon, Merel, Julnar, and Astona) widely grown in greenhouses to salinity (0, 25, 50, 75, 100 and 150 mM NaCl) grown in nutrient solutions. Shanon hybrid had a higher shoot growth in non-saline nutrient solution (control treatment) by 10, 48, 85% compared to Astona, Julnar, and Merel, respectively. Shoot growth decreased gradually with increasing NaCl concentrations in the nutrient solutions. There were differences among tomato hybrid in their salinity critical level in which 50% of the growth is decreased. Shanon had greater shoots compared to other tomato hybrid in all applied salinity levels. Salinity influenced roots which became stunted, thick and easy to break at 75 mM NaCl, and became slobby when NaCl reached 150 mM in the nutrient solution. Root systems were reduced by 71, 46, 67, and 56% at 150mM NaCl treatments for Astona, Julnar, Merel and Shanon compared to control in which no salinity was induced. Shanon had a long root system (136 m/plant) in the control treatment compared to 113, 90, and 77 for Astona, julnar, and Merel respectively. Root growth was reduced by salinity in all hybrids right from 25 mM NaCl, but however Shanon remains with the highest root length at all applied salinity levels. Shanon root system showed a higher efficiency to absorb nutrients and nutrient translocation to the shoots for most nutrients when compared to Merel, Julnar, and Astona. All inflow rates and specific accumulation rated in the shoots were reduced gradually with increasing salinity up to 150mM NaCl in the nutrient solutions. The critical salinity level (50% reduction) varies among tomato hybrid, 50 mM NaCl for Merel and Astona, 75 mM for Julnar, and 100 mM NaCl for Shanon.
Key words: tomato (Lycopersicon esculentum), salinity, nutrient uptake, hydroponic culture, greenhouse.
Full paper in Arabic: pdf