|Peairs, Frank - COLORADO STATE UNIVERSITY|
|Randolph, T - COLORADO STATE UNIVERSITY|
Submitted to: North American Barley Research Workshop Proceedings
Publication Type: Proceedings
Publication Acceptance Date: January 1, 2000
Publication Date: N/A
Interpretive Summary: Summary of information previously presented in other media; no new information provided; no interpretive summary required.
Technical Abstract: Infestations of Russian wheat aphid (RWA) cause significant damage to modern barley cultivars. Several sources of high-level resistance have been identified in the USDA-ARS National Small Grains Collection. Selections were made within accession PI355450 and released as STARS-9301B. In this study we determined utility of these genes in protecting malting quality characteristics and examined importance of timing of infestation (early versus late) in crop development. BC1F2 seedlings were made and advanced through head and head-row selections, with further RWA-infestations made in the greenhouse to identify homozygous resistant lines. Further selections were made among progeny of BC1F4-derived lines in several agronomically elite cultivars. In 1998, several lines were grown with their parents in Fort Collins and Aberdeen in replicated trials. Insecticides were used to control infestation in uninfested and late-infested plots. Aberdeen had a light infestation of RWAs, whereas Fort Collins was much more severe. Earl infestation caused severe damage, particularly at Fort Collins. Late- infestation did not cause significant damage at Aberdeen; at Fort Collins damage was significant but less than for early-infested plots. In contrast, STARS-9301B and the backcross-derived lines were relatively undamaged. All backcross-derived lines have been rated as highly-resistant based on greenhouse testing, except for moderately-resistant 95RWA96. Moderate resistance did not provide significant protection of agronomic and malting characteristics; 95RWA96 suffered significant damage. The data show that resistance alleles in STARS-9301B can confer excellent resistance to the RWA, and that resistance as measured by agronomic performance is correlated with resistance as measured by malting quality.