Diversity of currant (Ribes) species and cultivars infested by Cecidophyopsis mites in Latvia

Currants are the second most important berry crops in Latvia. During the last ten years the increase of gall mites (genus Cecidophyopsis) in Latvia in several currant plantations was observed. However, the distribution of the gall mites was unclear and in 2008 gall mite distribution and faunal studies were started. Sixty-five localities in Latvia were inspected and gall mites were observed in 38 of the 65 locations. Gall mites were observed from all types of inspected areas and on plants from three currant groups - blackcurrants (Ribes, subg. Ribes sect. Botrycarpum), redcurrants (Ribes, subg. Ribes sect. Ribes) and alpine currants (Ribes, subg. Berisia sect. Berisia). In commercial currant plantations, the blackcurrant cultivars 'Katyusha' and 'Mara Eglite' were most susceptible to gall mites. The blackcurrant cultivar 'Titania' was highly infested only in some areas. Gall mites are also a serious problem in currant plant genetic resource collections.