VATIS UPDATE Article

A research project carried out by the author at the Government Experimental Farm with the collaboration of the University of Malta Institute and supervised by Dr. Anthony Sacco on soil sterilisation in greenhouses using two environmentally friendly techniques – soil solarisation and biofumigation – has shown that the former is a very effective alternative to using chemicals to sterilise soil and can be used successfully in Malta due to the favourable climatic conditions.

Biofumigation was also found to be efficient but not as much as soil solarisation. Both techniques reduce the use of pesticides, improve yields and hence increase farmers’ profits. In the research, the efficacy of soil solarisation and biofumigation were compared using local soil in a greenhouse. The effectiveness of the treatments was assessed through their ability in reducing the nematode population in the soil, together with the crop yield, plant length, plant death, root structure, and also weed control.

Compared to a non-treatment control each treatment had a significant effect on the nematode population; however, soil solarisation was the most effective. Crops cultivated in solarised soil produced a significantly higher yield than crops cultivated in the biofumigated soil. They also reached maturity earlier, had a better rooting system and suffered less from diseases. Both treatments produced a significantly higher crop yield than the control untreated soil. From a weed control aspect soil solarisation proved to be the best choice under local conditions.