Annual Progress Report on Malting Barley Research March, 2002

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involving two susceptible backgrounds and 11 RWA-resistant sources were increased
towards evaluation as BC3F3 observation rows in 2002 and 2003 for future germplasm
development. 43,593 seedlings were screened towards germplasm development and
future germplasm release of winter, spring, feed and malt barleys. Six BC2F1 crosses
were made towards germplasm development involving 6 susceptible spring barleys and
one RWA-resistant source.
Genetic Studies
Complete genetic analysis has been performed on 9 out of a total of 108 RWA -resistant
lines developed by the USDA-ARS in Stillwater. All 9 lines showed multiple gene
control for RWA resistance. Genetic diversity studies are planned for all resistant lines to
determine if these lines carry different genes for resistance to RWA. This type of
analysis requires 3 years for development of seed necessary for each test. Complete
inheritance studies were conducted for 2 unadapted RWA-resistant germplasm lines.
Four spring F1 populations were increased to F2 for future use in inheritance studies.
Ten spring barley BC1F1 crosses, 9 spring barley F1/RF1 crosses, and 5 spring barley F1
crosses were make for future genetic studies. Eight TC1F1:F2 winter barley populations
and 14 TC1F1:F2 spring barley populations were increased for future genetic diversity
studies. Two spring barley and 11 winter barley TC1F1 populations were increased to
TC1F2 for future genetic diversity studies. Six spring barley testcrosses of resistant x
resistant F1 on susceptible barleys and, 5 spring barley R X R F1, and 30 winter barley R
X R F1 crosses were made in the spring of 2001 for future genetic diversity studies.
Cooperative screening
Six hundred advanced lines were screened for resistance for 3 barley breeders.
Other aphids
A small scale replicated study was conducted in the greenhouse on 10 barley lines
previously identified in the literature as either susceptible or resistant to Bird cherry oat
aphid (BCO) or resistant to Barley yellow dwarf mosaic virus. Seedlings were infested
with BCO at the 1 leaf stage and measurements on shoots and roots were made in an
attempt to determine the effect of Bird cherry oat aphid feeding on these lines as
seedlings. Identical measurments were made on an identical planting which was grown
in the same greenhouse at the same time but kept aphid free by repeated insecticide
applications. Analysis of data is ongoing.
Personnel
Germplasm Enhancement
Dolores W. Mornhinweg, Geneticist
David R. Porter, Research Geneticist