This species is probably the major pest of blackcurrant worldwide, although it has not been reported from North America or Tasmania. Besides causing swelling of the buds (known as 'big bud'), it is also the vector of Blackcurrant reversion virus. The mites emerge from the buds in springtime, to be dispersed as the buds open. Mites may move short distances along the infested plant to new buds, or may be carried on the bodies of insects or birds, but the vast majority is spread passively by wind or rainsplash. A single galled bud can contain up to 35 000 infective mites, and an infested bush can contain over 100 galls, so the build-up of inoculum within an affected plantation can be dramatic. There are few chemical sprays still permitted for C. ribis, and sulphur sprays are preferred within Europe. Removal of affected bushes, and ultimately infested plantations, is a vital means of reducing spread to new plantations, especially since bushes infected with blackcurrant reversion disease are more susceptible to mite colonisation and reproduction.
The SCRI variety Ben Hope is partially resistant to gall mite, with reduced susceptibility estimated at around 40 times less than that of other varieties.
Resistance to gall mite has been a breeding objective in most blackcurrant programmes for many years (Brennan, 1996). The most effective source of resistance used so far in western Europe is the Ce gene from gooseberry, and the introgression of this gene into R. nigrum is described by Knight et al. (1974). A long-term backcrossing programme to restore acceptable fruiting characters was undertaken, latterly at the Scottish Crop Research Institute, and potential new cultivars with resistance to C. ribis are now approaching commercialization.
Click on image to see enlarged version
| Gall mite infestation of buds |
| Picture of a gall mite infested blackcurrant bud taken in a scanning electron microscope |
Brennan RM (1996) Currants and gooseberries. In: Janick J & Moore JN (Eds.) Fruit Breeding, Vol. II: Vine and Small Fruits Crops. John Wiley and Sons, Inc. New York, pp. 191-295.
Knight RL, Keep E, Briggs JB & Parker JH (1974) Transference of resistance to blackcurrant gall mite, Cecidophyopsis ribis, from gooseberry to blackcurrant. Annals of Applied Biology 76, 123-130.
Return to list of pests and diseases