Alternatives to methyl bromide: chemical fumigants or integrated pest management systems?

Abstract

Changes in government and international policy, coupled with consideration of sustainable management strategies, will lead to the demise of methyl bromide as a soil disinfestation treatment for high value cropping industries within the next decade. Methyl bromide has provided excellent disease, pest and weed seed control and finding alternative chemical and non-chemical options which replace all the benefits of methyl bromide is providing a challenge to researchers. The advantages and disadvantages of alternative chemical and non-chemical control strategies are considered in this paper. Alternative chemicals treatments showing promise include lower application doses of methyl bromide, such as methyl bromide/chloropicrin (30∶70) and the use of other fumigant mixtures such as, 1,3-Dichloropropene/chloropicron and metham sodium combined with chloropicron. Investigations in Victoria have led to the development of an integrated pest management (IPM) strategy which partially offsets the need for methyl bromide in the flower bulb industry. IPM systems, however, will require more input from farmers, and support services, in such areas as the monitoring of pest and disease populations and the use of disease resistant stock and disease-free nursery material, before IPM systems fully offset the benefits of methyl bromide. Consideration of grower profits, reliability and insurance afforded by soil disinfestation with methyl bromide must be taken into account when assessing the suitability of alternatives.