New resistance

The Home-Grown Cereals Authority (HGCA) has reported new resistance to fungicides used to control diseases in cereals. The benzimidazole (MBC) group has shown widespread resistance for the first time to the fungus Rhynchosporium secalis one of the major disease of cereals in the UK. This resistance may cause 'performance difficulties' especially where weather conditions favour the disease.  
    HGCA researchers highlight the dependence on chemical control suggesting that growers mix demethylase inhibiting fungicides (DMIs), such as triadimenol with morpholine fungicides in order to reduce resistance pressure building .

Fungicide resistance in cereal pathogens 1991-96, Project report No. 139, HGCA, Hamlyn House, Highgate Hill, London, N19 5PR, £7.00, pp.

[This article first appeared in Pesticides News No. 38, December 1997, page 19]