NON-CHEMICAL ALTERNATIVES TO METHYL BROMIDE FOR STRAWBERRY: BIOSOLARIZATION AS CASE-STUDY IN HUELVA (SPAIN)

The main uncertainty for strawberry production without methyl bromide (MB) in Mediterranean European countries is the implementation of the Directive 91/414/EEC. This presentation is focused on soil solarization plus biofumigation (biosolarization). A case-study has been carried out for strawberry cultivation in our Experimental Farm ‘El Cebollar’ (IFAPA) (Moguer, Huelva) since 1999. The main steps in this methodology are: 1) Incorporation to soil of 25.000-30.000 kg/ha of biofumigant chicken manure (second week of July). 2) Sprinkler irrigation (third week of July). 3) Application of LDPE transparent film for soil solarization (third week of July). 4) Biosolarization effect into the soil (from third week of July up to end of August). 5) Plastic removal (early September). 6) Formation and mulching of beds (mid-September). 7) Plantings (from early to mid October). The improvements in this case-study with biosolarization are: 1) increase of organic matter content in the soil; 2) better control of weeds; 3) better productivity. The cost of our biosolarization system represents a reduction of around 25% in relation to standard methyl bromide plus chloropicrin (50:50 w/w) shank-application.