Assessing Russian Wheat Aphid Resistance in Hungarian and South African Germplasm

Abstract

Russian wheat aphid (Diuraphis noxia) is a serious pest of wheat in South Africa and can cause up to 80% yield loss on susceptible cultivars if not controlled. Although present in Hungary, Russian wheat aphid is not an economically significant pest of wheat and this is possibly due to factors such as host plant resistance in Hungarian germplasm and the presence of effective natural enemies such as parasitoids, predators and entomopathogenic fungi. Previous studies have suggested that wheat lines resistant in South Africa may be susceptible to Hungarian Russian wheat aphid. This would have far-reaching implications for resistance breeding against this pest. A collaborative study was thus undertaken to evaluate a group of 45 Hungarian and 15 South African wheat cultivars in both countries using the same methodology. Halt and Betta were used as the resistant and susceptible controls respectively. Germplasm identified as resistant in this study could be utilised in wheat breeding programmes to develop Russian wheat aphid resistant cultivars.