Evaluation of chemical strategies as alternatives to methyl bromide for the control of root-knot nematodes in greenhouse cultivated crops

If methyl bromide is phased out for greenhouse use by 1 January 2005 it will cause many difficulties in agricultural industries that are now heavily reliant on its use. Three field experiments were conducted to compare management tactics on tomato and cucumber in commercial greenhouses naturally infested with root-knot nematodes (Meloidogyne spp.). Methyl bromide was used as a reference treatment and was consistently superior to all the other treatments and combinations of other fumigants with contact nematicides. A significant reduction of nematode juveniles and root-galling index was observed in plots treated with either metham sodium and cadusafos or 1,3-dichloropropene and cadusafos. Nematode decrease was greater when these three chemicals were applied in the same plots. Good nematode control based on the use of different chemicals combinations can be achieved only for one cropping season and therefore nematode management measures must be employed for the next cropping season