Submitted to: International Conference on Methyl Bromide Alternatives and Emissions Reductions
Publication Type: Proceedings
Publication Acceptance Date: 9/1/2009
Publication Date: 11/10/2009
Citation: Gerik, J. S., Klose, S., Ajwa, H., and Wilen, C. 2009. Gladiolus production with methyl bromide alternatives - Pacific area-wide program for MBA. Page 28 in: Proc Annu. Intl. Res. Conf. Methyl Bromide Alternatives Emissions Reductions. Interpretive Summary: Two trials were conducted in Santa Maria to test alternatives to methyl bromide for Gladiolus bulb production. In one trial the fumigants were delivered by drip irrigation and the second trial the fumigants were applied by shank injection. The chemicals tested included Telone, chloropicrin, metam potassium, iodomethane, alone and in combination with each other. Methyl bromide/chloropicrin treatment was included as the standard control. Most or the combinations controlled soilborne plant pathogens as well or better than the standard treatment. Bulb yield was improved with all chemicals in both trial compared to the untreated controls. Bulb yield from the alternative treatments was generally comparable to the standard methyl bromide/chloropicrin treatment.
Technical Abstract: Cut flower and ornamental bulb industries rely heavily on a methyl bromide/chloropicrin (MB/Pic) mixture as a key pest management tool. The loss of MB will seriously affect the cut flower and bulb industry, and, in the future, will require growers to use alternative fumigants. Therefore, efficacy of shank and drip-applied alternative fumigants (normal and reduced label rates) under high barrier film (virtually impermeable film, VIF) to control soil-borne pathogens and to produce a Gladiolus bulb crop was tested in Santa Maria relative to the standard MB/Pic shank fumigation at 350 lb/acre and an untreated soil. The primary goal of this project is to demonstrate alternative fumigation systems at on-farm trials to facilitate the implementation of alternative pest management strategies by the California cut flower and ornamental bulb industry. All the chemical treatments reduced the pathogen populations in both the drip and the shank trial compared to the untreated controls except for Telone C35 which did not perform well for control of Fusarium oxysporum in the shank trial. The chemicals seemed to better reduce populations in the shank trial compared to the drip trial. Most of the chemicals controlled pathogens as well as the standard methyl bromide/chloropicrin treatment. Bulb yield was improved with all chemicals in both trial compared to the untreated controls. Bulb yield from the alternative treatments was generally comparable to the standard methyl bromide/chloropicrin treatment. Overall, pathogen and yield seemed to be slightly better in the shank treatments compared to the drip treatments. From these results, it appears that a successful Gladiolus bulb crop can be grown with these alternative treatments.