Resistance in Ethiopian Barley Landraces to the Russian Wheat Aphid (Diuraphis noxia Mordvilko)

Abstract

The Russian Wheat Aphid, RWA, (Diuraphis noxia Mordvilko) is an important pest o f barley in Ethiopia. Chemical control o f RWA with spray and seed dressing could give limited protection because o f the leaf enrolling behaviour o f the insect which reduces
the effect o f the former and the limited efficacy the latter method has with plant growth stages. The alternative, which requires less investment, no special skill and which is sustainable and friendly to the environment is the use o f resistant cultivar. Based on this fact, screening o f land races o f barley was carried out at Holetta and Sheno (Ethiopia) by selecting more than 1400 lines from land races. A total o f 29 lines were found to have good level o f resistance. With further evaluation, among these lines 3379- 17, 3296-03, 1671-06, and 1726-17 were found to have better plant stand and good level o f resistance to the pest. But, it was 3296-15, which had acceptable agronomic merits and expressed high level o f tolerance to the pest, though it supported more aphids than the accessions mentioned above. From this study it was confirmed that there is a possibility o f getting barley accessions with good level of resistance to thepest if more Ethiopian collections are screened