Articles
DIMETHYL DISULFIDE AS A NEW CHEMICAL POTENTIAL ALTERNATIVE TO METHYL BROMIDE IN SOIL DISINFESTATION IN FRANCE
Article number
698_8
Pages
71 – 76
Language
English
Abstract
The use of chemical compounds and especially fumigants still is a safe preventative method to control high infestation levels of soilborne pathogens, nematodes and weeds.
A new fumigant, dimethyl disulfide (DMDS) could be an alternative for French growers with respect to the phase-out of methyl bromide (MeBr) for soil disinfestion.
The more the availability of other fumigants is very limited: chloropicrin is not registered in France, nor the application of fumigants via drip irrigation systems.
After preliminary laboratory experiments, in which are shown very promising results on several soil borne fungi, field experiments were carried out between 2002 and 2004 in French practical conditions.
Objectives were: (i) to confirm fungicidal spectrum of DMDS, (ii) to understand the gas behaviour of this fumigant into the soil profile and to calculate in situ lethal Concentration Time Products (CTPs), (iii) to evaluate new methods of applications and especially via the existing drip irrigation, using several amounts of water.
Experiments were carried out on micro-plots with artificial inoculation with soil borne pathogens and on natural infested soils.
Pure DMDS was applied by shank injection and a 95 EC formulation by drip irrigation with two rates of water, 6 and 12 L/m2. Rates of active ingredients were 0.03, 0.06 and 0.08 kg/m2. All plots were covered with a Virtually Impermeable Film (VIF) during one week.
Calibrated Thermal Conductivity Cells (Fumiscope or Gow-Mac) were used for the monitoring of gas concentrations and to calculate CTPs.
A 100% control was achieved for the fungi Rhizoctonia solani and Verticillium dahliae at a rate of 0.08 kg/m2; for Sclerotium rolfsii only 85% mortality, as compared to MeBr, was achieved.
DMDS gas behaviour studies confirm a quick diffusion into the soil profile, especially by injection.
An average CTP between 3821 g.h/m3 and 7783 g.h/m3 at 15 cm and 30 cm soil depths was obtained in all plots.
Using drip irrigation, CTP seems higher at 15 cm depth but lower at 30 cm, and there is no significant statistical difference between the application with 6 and 12 L/m2 of water.
Marketable yields of strawberries were not significantly different between methyl bromide and DMDS 0.08 kg/m2.
A new fumigant, dimethyl disulfide (DMDS) could be an alternative for French growers with respect to the phase-out of methyl bromide (MeBr) for soil disinfestion.
The more the availability of other fumigants is very limited: chloropicrin is not registered in France, nor the application of fumigants via drip irrigation systems.
After preliminary laboratory experiments, in which are shown very promising results on several soil borne fungi, field experiments were carried out between 2002 and 2004 in French practical conditions.
Objectives were: (i) to confirm fungicidal spectrum of DMDS, (ii) to understand the gas behaviour of this fumigant into the soil profile and to calculate in situ lethal Concentration Time Products (CTPs), (iii) to evaluate new methods of applications and especially via the existing drip irrigation, using several amounts of water.
Experiments were carried out on micro-plots with artificial inoculation with soil borne pathogens and on natural infested soils.
Pure DMDS was applied by shank injection and a 95 EC formulation by drip irrigation with two rates of water, 6 and 12 L/m2. Rates of active ingredients were 0.03, 0.06 and 0.08 kg/m2. All plots were covered with a Virtually Impermeable Film (VIF) during one week.
Calibrated Thermal Conductivity Cells (Fumiscope or Gow-Mac) were used for the monitoring of gas concentrations and to calculate CTPs.
A 100% control was achieved for the fungi Rhizoctonia solani and Verticillium dahliae at a rate of 0.08 kg/m2; for Sclerotium rolfsii only 85% mortality, as compared to MeBr, was achieved.
DMDS gas behaviour studies confirm a quick diffusion into the soil profile, especially by injection.
An average CTP between 3821 g.h/m3 and 7783 g.h/m3 at 15 cm and 30 cm soil depths was obtained in all plots.
Using drip irrigation, CTP seems higher at 15 cm depth but lower at 30 cm, and there is no significant statistical difference between the application with 6 and 12 L/m2 of water.
Marketable yields of strawberries were not significantly different between methyl bromide and DMDS 0.08 kg/m2.
Publication
Authors
J. Fritsch
Keywords
gas diffusion, Concentration-Time-Product, soil borne pathogens, drip application, shank application
Online Articles (43)