EFFECTS OF SUBSTRATE SOLARIZATION ON TOMATO SOILLESS CULTIVATION

Tomato plants (Lycopersicon esculentum L.) were grown in soilless culture under greenhouse conditions at the experimental farm of the University of Palermo, to evaluate the effects of substrate (coconut coir dust) solarization on yield and fruit quality of two different varieties of tomato.
The soilless cultivation substrate should be economic, easily available and eco-compatible.
The use of recycled substrate involves the accumulation of residue of the previous crop (D’Anna et al., 2004), but an organic substrate (like coconut coir dust), with a continuous reutilization, raises in pH, conductivity, decomposition of organic matter and soilborne crop pest (Lemaire et al., 1998). The solarization of substrate can be a way to reduce soil borne inoculum of crop pests and also increase the concentration of soluble mineral nutrients (Stapleton, 2000). The research was carried out in 2005/2006, on the experimental farm of the Horticultural and Floricultural Branch of the Department AAT (Agronomia Ambientale e Territoriale) of the University of Palermo.
The soilless cultivation was carried out in a 264 m² glasshouse.
Two type of tomatoes were compared: a plum-type (cv.
Piccadilly) and a cherry-type (cv.
Shiren). They were trained on new and solarized coconut coir dust substrate, previously used for 2 harvesting cycles of tomato and pepper.
Harvest started in February and finished in May 2006. Total production in new and solarized substrate wasn’t significantly different; the average yield was 73 t/ha.
Piccadilly (88.1 t/ha) was more productive than Shiren (57.8 t/ha), because Piccadilly’s fruits were bigger than Shiren’s; in fact, the average weight of Shiren’s fruit was 17.2 g and Piccadilly’s 38.3 g.
The unmarketable yield was 11% of the total production; cultivation in solarized substrate caused less waste (9.7%). The quality of fruits wasn’t influenced by the treatment of substrate and cultivar.
Firmness of Piccadilly’s fruits (392.8 g) and Shiren’s (388.6 g) was similar; fruit sweetness is higher in Shiren’s (7.7 °Brix) than in Piccadilly’s (5.5 °Brix). The substrate used various times could change its physical and chemical characteristics (Shinoara et al., 1999), but isn’t a limit if solarized before utilization.
Experimental results, for quality and quantity production, are the same utilising a new substrate or an older solarized one.
It’s suitable to use a recycled substrate without having problems in management.

International Symposium on High Technology for Greenhouse System Management: Greensys2007

A. Moncada, G. Caracciolo, F. D’Anna

greenhouse, coconut coir dust substrate, cultivar

https://doi.org/10.17660/ActaHortic.2008.801.183