INFLUENCE OF SALINITY AND IRRIGATION METHOD ON ZUCCHINI PLANTS GROWN IN CLOSED-SOILLESS SYSTEM

     Zucchini plants (Cucurbita pepo L. var Afrodite) were grown in a closed soilless system from 28 March to 6 June 2002 under greenhouse conditions at the Experimental Farm of Tuscia University to evaluate the impact of two irrigation methods (drip- and sub-irrigation) and two saline waters (1 and 34 mM of NaCl) on growth, yield and water use efficiency. Electrical conductivity of substrate increased by increasing the salt concentration of the nutrient solution and by changing from drip to sub-irrigation method. Irrigation method did not influence the marketable yield at 1 mM of NaCl (avg 2.27 kg/plant), while at 34 mM of NaCl plants grown with sub-irrigation method gave lower yield than those grown with drip irrigation system (0.42 vs. 0.95 kg/plant). Dry weight of fruits, leaves, stems and flowers showed a similar trend due to the lack of significant differences among treatments on dry matter of plant tissues (leaves, stems, flowers, and fruits). Maximum water use efficiency was observed with drip irrigation at 34 mM of NaCl and with sub-irrigation at 1 mM of NaCl.

Download Adobe Acrobat Reader (free software to read PDF files)