The influence of drip irrigation or subirrigation on tomato grown in closed-loop substrate culture with saline water

• Published in: Scientia horticulturae Vol. 107; no. 4; pp. 365 - 372
• Main Authors: Incrocci, L., Malorgio, F., Della Bartola, A., Pardossi, A.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 27-02-2006; Elsevier
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; Hydroponics; Lycopersicon esculentum mill; NaCl; Salinity; Soilless culture; Soilless cultures. Co2 fertilization; Soilless cultures. Protected cultivation; Subirrigation; Substrate; Substrate; Soilless culture; Hydroponics; NaCl; Subirrigation; Lycopersicon esculentum mill; Salinity; Closed loop; Soilless cultivation; Horticulture; Brackish water; Sodium chloride; Tomato; Subsurface irrigation; Vegetable crop; Dicotyledones; Hydroponic cultivation; Angiospermae; Trickle irrigation; Lycopersicon esculentum; Spermatophyta; Solanaceae; NaCI
• ISSN: 0304-4238; 1879-1018
• DOI: 10.1016/j.scienta.2005.12.001

In closed-loop soilless culture, one of the most relevant problems may be the accumulation in the recirculating nutrient solution of ions contained in irrigation water that are not or scarcely absorbed by the plants (e.g. Na, Cl) In order to verify the possibility to reduce the rate of recirculating water salinisation by means of subirrigation, an experiment was carried out in the spring of 2002 and 2004, with tomato plants (cv. Jama) grown in glasshouse and watered by conventional drip irrigation (D) or by subirrigation (trough bench system; S). The plants were cultivated in pots filled with a peat-perlite substrate for approximately 3 months and fed with complete nutrient solution, which was prepared with fresh water containing 10
mol
m
−3 NaCl; the nutrient solution in the collecting tank was replaced when the value of electrical conductivity (EC) exceeded 6.0
dS
m
−1. Water and nutrient crop use, salt accumulation in the substrate, and fruit yield were monitored. In S culture, the composition and EC of the recirculating nutrient solution changed slightly, while in D treatment there was a fast water salinisation that made it necessary to flushed out the nutrient solution in six different occasions, with consequent loss of water and fertilisers. In S culture, the upward water movement in the substrate, coupled with selective mineral uptake by the roots, caused salinity build-up in the upper region of the substrate, which was associated with Na
+ accumulation. No significant influence of irrigation methods on fruit yield and quality was observed. These findings suggest that subirrigation can be a tool to reduce the water consumption and nutrient runoff in closed-loop substrate culture of tomato conducted with saline water.