COMPARISON OF SOME TURKISH ORIGINATED ORGANIC AND INORGANIC SUBSTRATES FOR TOMATO SOILLESS CULTURE

Soilless culture is not a practice used on a large scale by greenhouse growers in Turkey. The main reason for this is the high price of imported substrates (like rockwool or peat) and the initial installation equipment needed for the technique.

In this study, Turkish originated "volcanic tuff," "peat" and "spent mushroom compost" have been analyzed and tested in comparison with "rockwool" and "soil (control)".

According to the results of two years greenhouse experiments, the highest yield was obtained from peat (25.0 kg/m²), rockwool (23.3 kg/m²) and spent mushroom compost (22.4 kg/m²). There was no significant difference between these three substrates from the point of view of yield. Volcanic tuff and soil have yielded 20.3 kg/m² and 20.0 kg/m² respectively. The range of early yields was as follows: rockwool (3.9 kg/m²), peat (3.3 kg/m²), spent mushroom compost (2.9 kg/m²), volcanic tuff (2.0 kg/m²) and soil (0.7 kg/m²).

Analyses of the physical and chemical properties of the substrates and of leaves of tomatoes growing in different substrates have shown that peat and mushroom compost could be used successfully in greenhouse tomato growing.