Four years research on improved soil solarization and other alternatives to methyl bromide on strawberry crops

Abstract

To develop alternatives to MB, it is necessary to study not only the efficacy of the treatments but also their long-term effects and the feasibility of repeating the treatment in the same field several years consecutively. A four year experiment was carried out in a strawberry field in which there were established seven treatments: non treated control; standard dosage application of MB (60g/m2 ); half dosage application of MB (30g/m2) using VIF tarp; moderate rates of manure (5kg/m2) combined with solarization; reduced dosages of metam- sodium (MS) (35g/m2) combined with solarization; MS at standard dosages (144g/m2); and fresh manure at high rates (15kg/m2). The solarization treatments were split in two sub-treatments in the last year, in such a way that a half of the solarization combined with manure treatment of the third year was replaced by solarization combined with MS and vice versa, so that the experiment had a total of 9 treatments. After four years of research, we can infer that improved solarization with manure offers the better possible alternative when data of the first two years are considered but there is a loss of efficacy if these treatments are uninterruptedly applied longer than two years. The replacement of MS for manure produced less marketable yield losses than the reverse replacement.