Effects of Monopotassium-phosphate, Nano-calcium fertilizer, Acetyl salicylic acid and Glycinebetaine application on growth and production of tomato (Solanum lycopersicum) crop under salt stress
¹University of Forestry, 10 Kliment Ohridski blvd, BG1797 Sofia, Bulgaria
²Lebanese University, Faculty of Agricultural Engineering and Veterinary Medicine, Department of Food Technology, Dekwaneh, Beirut, Lebanon
³Lebanese University, Faculty of Agricultural Engineering and Veterinary Medicine, Department of Horticulture, Dekwaneh, Beirut, Lebanon
Salinity problem is increasingly affecting tomato production in Lebanon leading to economic losses. The study investigated the potential effects of nano-Calcium (LITHOVIT®), monopotassium-phosphate (MKP: 0-52-34) fertilizers, Acetyl salicylic acid (Aspirin) and the osmoregulator glycinebetaine (GB) on salt tolerance of potted determinate tomato (variety Sila) plants in open-field. Salt stress was induced by irrigation solutions of EC = 2, 4, 6, 8 and 10 mS cm-1 and MKP (2, 3 and 3.5 g L-1), Aspirin (50, 75 and 100 mg L-1), LITHOVIT® (0.5, 0.75 and 1 g L-1) and GB (4.5, 6 and 7.5 g L-1) were applied through foliar application or fertigation. Comparisons between treated and non-treated plants at each salinity level (control) showed that LITHOVIT® decreased the salinity-induced reductions in stem diameter, leaf area and chlorophyll content. Medium concentrations of LITHOVIT® and Aspirin improved stem diameter and all products except Glycinebetaine improved flower number compared to control. Root dry weight and Root Mass Fraction were mostly enhanced in MKP and Aspirin-treated plants. Best improvement in plant yield (76%) was obtained with low concentrations of MKP and LITHOVIT® at EC = 8 mS cm-1 due to improvement in fruit number rather than fruit weight. Consequently, LITHOVIT® and MKP showed superior effects under salt stress compared to Aspirin and Glycinebtaine.