Methyl bromide alternatives evaluated for California strawberry nurseries

Abstract

The recent phase-out of the soil fumigant methyl bromide (MB) due to its impact on stratospheric ozone presents a huge challenge to strawberry nursery producers. We evaluated the effectiveness of alternative fumigants on soil pests and plant productivity, as well as production costs in California strawberry nurseries. Our trials followed nursery stock through low- and high-elevation phases of runnerplant propagation and a complete cycle of fruit production in coastal fields. Plant yields from the nurseries and fruit yields from Oxnard and Watsonville indicated that nursery plots treated with iodomethane plus chloropicrin, with 1,3-dichloropropene followed by dazomet, and with chloropicrin followed by dazomet produced runner-plant yields that were similar to methyl bromide plus chloropicrin. However, our economic analysis suggests that nursery profitability may nonetheless suffer from the loss of methyl bromide.