Article by: Hari Yellina (Orchard Tech)
Chloropicrin is a soil fumigant that has been used commercially for more than 100 years. It has registrations in more than 30 countries, with new countries adding to that list. It is well recognised as an effective soil disinfestation tool, critical to high-value horticulture, where crop loss due to soil pests is significant.
Because of its documented and favourable effects on soil health, its lack of residues, or soil contamination issues, we continue to see chloropicrin used as a safe and effective pre-plant soil treatment. It is known that other soil disinfestation treatments have a broader biocidal effect than chloropicrin, and are more detrimental to some key beneficial organisms.
Significant other benefits following an application of chloropicrin have been long observed and have for the most part remained less understood. In addition to reducing the populations of soil pests including pathogenic fungi, nematodes, and insects, chloropicrin stimulates the proliferation of beneficial soil microbes in the weeks and months following treatment.
This includes Trichoderma spp. and root colonizing pseudomonads. In addition, chloropicrin does not negatively affect the populations of ectomycorrhizae. Following soil fumigation with chloropicrin, the levels of essential plant nutrients are increased. This is caused by the initial breakdown and decaying of soil microflora cells.