Research Article
Ragab ME, Omaima M Sawan, F
Abstract
Studying the alleviating of water stress for tomato plants cultivated in a sandy soil and were exposed to deficit irrigation (DI) treatments; 100%, 85%, 70% and 55% of ETo, using two irrigation systems (surface drip irrigation (SDI) and subsurface drip irrigation (SSDI), and spraying the plants by glycine betaine (GB) (0, 5, 10 and 20 mM/l) as a foliar application. Results clearly reported that the full irrigation treatment 100% ETo produced the highest significant values of total leaves area and fresh and dry weights of tomato leaves per plant, number of flowers per plant and total marketable yield, while DI treatments (85%, 70% and 55% of ETo) significantly decreased all of these characteristics. There was a positive effect on many tomato fruit quality characteristics; TSS, total sugars and ascorbic acid content. Tomato plants grown under subsurface drip irrigation system have the highest significant values for vegetative growth, flowering and fruit yield and quality parameters, compared to SDI system. Glycine betaine treatments enhanced the growth of tomato plants grown under deficit irrigation water, where plants received GB at 10 mM/l had the maximum values for studying characteristics. While, fruit quality characteristics not significantly affected by GB treatments. Results reported that, When DI treatments (85%, 70% and 55% ETo) decreased total marketable yield by (14.38%, 25.08% and 48.77%) and (14.23%, 24.78% and 47.03%), spraying the plants by GB at 10 mM/l increased it by (10.95%, 10.11% and 22.85%) and (12.92%, 9.26% and 20.74%), in the first and second seasons, respectively.