Methyl bromide alternatives on horticultural crops

[EN] A very intensive crop rotation, with three to four crops per year, typical in Valencia, frequently includes the earth almond Cyperus sculentus (Xufa) that acts as a real weed for the next crop. Methyl bromide (MB) is the preferred fumigant to control both diseases and weeds in this kind of rotation. The crop rotation begun by an escarole crop (September to January), followed by potato (February to May) and watermelon (May to August). Disinfestation treatments to compare were: 1) Non fumigated control; 2) Standard MB polyethylene (PE) 60g/ m2 ; 3) MB VIF 30g/ m2; 4) Solarization + Manure 5Kg/ m2; 5) Solarization + MS (N-Methyl Dithiocarbamate Sodic 40% p/v) 36g/ m2; 6) Telone C35 Mechanical application 40g/ m2; 7) Telone II (1,3-Dichloropropene 93%p/p)18g/ m2 + MS 108g/m2 All treatments are rather effective in controlling weeds when compared to the non treated control, the increase in cost of removing weeds is particularly high if none treatment is applied. Only the escarole crop suffered the attack of Scleotinia minar and treatments 2 and 7 gave a very good protection as is revealed by a low percent of debris. No specific pathogens were found in potato and watermelon crops, nevertheless grafting is confirmed as a very good technique that increases the yield of watermelon. Solarization treatments did not differ significantly from control in this experiment. Treatment 7 is as good as MB in sorne of the instances, but disinfestation with MB is absolutely necessary if non grafted plants of watermelon are employed.