Effects of CO2 enrichment on vegetative growth, yield and quality of greenhouse-grown tomatoes in soil and soilless cultures

This research was conducted to determine the effects of CO2 enrichment on yield and vegetative growth of tomato (Lycopersicon esculentum Mill.) in both soil and soilless (bag) cultures for the period of 1993 and 1995. While in the first year of the experiment plants were grown as a spring crop only, in the second year both spring and long term crops were grown. The experiments were set up as a randomized complete block factorial design. Sander Fl;and Fantastic Fl were used for the spring and the long term growing seasons respectively. When the temperature in the greenhouse was below 27 degrees C, 1000 ppm CO2 was applied into the greenhouse in day light and when the temperature was above 27 degrees C CO2 enrichment process was stopped and the ventilation system was opened. During the experiments, plant height (15 day-intervals), leaf chlorophyll content, net assimilation rate, relative growth rate, number of flowers and fruits per cluster were determined. Fruit yield and quality characteristics (vitamin C, flesh firmness, titratable acidity, pH, total soluble solids and dry matter content) were also measured. The results showed that whilst CO2 enrichment increased only the early yield for both years of the spring growing season, the application increased both the early yield and total yield by 37 % and 43 %, respectively for long term crop growing.