Submitted to: Proceedings International Barley Genetics Symposium
Publication Type: Proceedings
Publication Acceptance Date: July 30, 1996
Publication Date: N/A
Interpretive Summary: Summary article; no new research reported; no interpretive summary required.
Technical Abstract: The Russian wheat aphid (RWA) is a devastating pest of barley grown in the intermountain regions of the western United States. All barley cultivars currently in commercial production are susceptible to RWA. Leaf unrolling in response to aphid feeding not only reduces yield but also provides an optimum environment for aphid reproduction and protects the aphids from contact insecticides and natural predators. Repeated sprayings of expensiv and environmentally threatening systemic insecticides, which can be residual in barley endproducts, are necessary to control RWA. A new germplasm line that has genetic resistance to RWA has been identified and genetically characterized. This line differs genetically from the previously released germplasm line to give genetic diversity for RWA resistance. Aphids have often been observed in the past to overcome resistance within a fairly short time of release of a resistant cultivar. The availability of germplasm lines that differ genetically for RWA resistance gives breeders the opportunity to develop RWA-resistant cultivars that differ genetically for resistance. This diversity should decrease the selection pressure on the aphid and thus decrease the chance of the aphid overcoming the resistance. The release of this new germplasm line would be welcome by both public and private barley breeders and would ultimately be of benefit to growers and extension personnel.