Submitted to: Proceedings of International Research Conference on Methyl Bromide Alternatives
Publication Type: Abstract Only
Publication Acceptance Date: December 4, 2001
Publication Date: N/A
Technical Abstract: The objective of this research was to develop an integrated approach to increasing strawberry yields without the use of methyl bromide. The design of this study is a result of five years of research at Fresno, Parlier, and Salinas. Preliminary screening of 130 plant growth promoting rhizobacteria (PGPR) strains was done at Fresno and Parlier, and the most promising treatments were tested in advanced trials at Parlier and Salinas. PGPR and chloropicrin (pic) fumigation were found to have an additive effect, therefore, this trial includes several PGPR strains in pic treated soil. The results here are consistent with earlier results, and with the results of other researchers. Yield in plots with pic treatment alone is slightly less than MBr alone, yield in non-treated plots is significantly lower. Surprisingly, yield in some of the pic plus PGPR plots is even higher than in MBr plots. This integrated approach is advantageous because it does not require a major change in the cropping system. PGPR lend themselves to application through the drip irrigation system, and chloropicrin is already in use in combination with MBr. Little or no additional equipment is needed since many growers already apply fertilizer through the irrigation system. Some chemical alternatives require a long waiting period between crops, resulting in loss of yield and revenue. Strawberry yields achieved with this combination of treatments are equal to or better than those achieved with methyl bromide. These strains belong to Gustafson, Inc., producers of BioLogic and Kodiak, a biological widely used in cotton production. Estimated cost for use of a PGPR product in strawberry production is around $250 per acre.