SOIL SOLARIZATION AND FUMIGATION OF STRAWBERRY PLOTS
Two series of field experiments were carried out at Tira, Israel, to determine the short- and long-term effects of solarization and fumigation with methyl bromide (MB) on strawberry growth and yield and on weed control. In the first series of experiments (1976–80) solarization and MB increased the yield in the first year by 14% and 13% respectively, over the untreated control. The plots were solarized or fumigated again in the following year, with respective increases in yields of 52% and 58%. Solarization had no residual effect in the second year. In the third year, the plots were solarized (either after a single preirrigation or with additional drip irrigations during solarization) or fumigated. The yields were increased by these treatments by 51%, 61%, and 67%, respectively. In these experiments, weed control was observed and no major soilborne diseases were detected. In the second series of experiments, solarization was compared with MB, with and without herbicides. In one experiment, the yield in the solarized plots was 18–31% higher than in the respective MB plots. Addition of herbicides did not affect the yield. In a second experiment, the yields in solarization and MB treatments did not differ from those of the untreated control. In conclusion, both solarization and fumigation increased yield even in the absence of major pathogens. Solarization is an additional nonchemical control method which is effective against potential pathogens.