Dimethyl disulfide use in combination with chloropicrin or metam sodium for soilborne pest management

J.H. Freeman, M.C. Stevens, N.S. Boyd
Dimethyl disulfide (DMDS) has been researched extensively and is now labeled for pre-plant soil fumigation use in countries worldwide. DMDS can be applied through shank injection or drip application and has been proven to be effective on a broad spectrum of soilborne pests such as weeds, pathogens, and nematodes. In the USA, DMDS is commonly mixed with chloropicrin (Pic) prior to application and this combination is very effective. Unfortunately, extensive Pic use is limited to certain countries and to specific months in other countries. Information on DMDS use without Pic is limited and it is unclear if it could be used alone and maintain pest efficacy. Metam sodium (MNa) is one of the most used agricultural pesticides in the world. Pest management with MNa can be good on many soilborne pests but results are often inconsistent. MNa could be a substitute for Pic in geographies or months where DMDS use is permitted but Pic use is not. The research was conducted during 2017 to determine the efficacy of DMDS when applied alone or in combination with either Pic or MNa for open field, raised-bed plasticulture production of cantaloupe. Totally impermeable film containing a barrier layer of ethylene vinyl alcohol was used in all DMDS treatments. When DMDS was applied in combination with Pic or MNa, nutsedge (Cyperus rotundus and C. esculentus) populations were significantly less than in the non-treated control and the commercial standard combination of 1,3-dichloropropene and Pic by 60 days after treatment. No significant differences were detected between various DMDS treatments. These data illustrate the potential of supplementing MNa for Pic in areas of restricted Pic use while maintaining control of nutsedge species.
Freeman, J.H., Stevens, M.C. and Boyd, N.S. (2020). Dimethyl disulfide use in combination with chloropicrin or metam sodium for soilborne pest management. Acta Hortic. 1270, 219-224
DOI: 10.17660/ActaHortic.2020.1270.26
soil fumigant, dimethyl disulfide, Cyperus, chloropicrin, metam sodium, nutsedge

Acta Horticulturae