Registration of "Orca" Barley

"Orca" (Reg. No. ___, PI ______) spring barley (Hordeum vulgare L.) was developed by the Oregon Agricultural Exp. Stn. and released in 1998. The University of Idaho Agric. Exp. Stn. and the Washington State University Exp. Stn. participated in the release.

Orca, tested as BSR45 and "Icaro", was derived from the cross of "Calicuchima-sib" x "Bowman-derivative". Calicuchima-sib is a six-row spring barley germplasm line developed by the International Center for Agricultural Research in the Dry Areas (ICARDA) barley breeding program based in Mexico. The pedigree of Calicuchima-sib is "LBIran/UNA8271//Gloria/Comanche". Calicuchima-sib is resistant to the spectrum of stripe rust (Puccinia striiformis f.sp. hordei), leaf rust (Puccinia hordei) and scald (Rhynchosporium secalis) virulence currently encountered in Mexico and the Andean zone of South America. Bowman (PI483237, Reg. No. 197) is a two-row spring barley released by the North Dakota State University Exp. Stn. in 1984. The pedigree of Bowman is ND2685/ND1156//"Hector". The Bowman-derivative (ND586/CIho 2376//ND4880)4*Bowman) carries the Ryd2 gene for resistance to Barley Yellow Dwarf Virus (BYDV) from CIho 2376 and was kindly provided by Dr. Jerry Franckowiak of North Dakota State University. Orca is one of 110 doubled haploid lines derived from the F₁ of Calicuchima-sib/Bowman- derivative. The doubled haploids were developed by the Hordeum bulbosum technique, as described by Chen and Hayes (1989). The doubled haploid population was used to map genes conferring resistance to barley stripe rust and other diseases (Chen et al., 1994; Hayes et al., 1996). Five hundred heads of Orca were selected from a phenotypically uniform block in New Zealand in 1997 and were grown in head rows by the Washington State Crop Improvement Association in 1997. This seed was harvested in bulk for breeder seed.

Orca is a two-row, rough-awned, white-aleurone spring barley with short rachilla hair. Additional genotype identifiers are 35 Restriction Fragment Length Polymorphisms (RFLPs) and 15 Simple Sequence Repeats (SSRs) (Hayes et al., 1996; Korte et al., 1997).

Orca is resistant to barley stripe rust under field conditions in Mexico, South America, and the Pacific Northwest. There is limited symptom development on adult plants (average 10% severity on a plot basis in >100 tests). This may indicate that Orca has adult plant, quantitative resistance (sensu Sandoval et al., 1998). The primary determinants of stripe rust resistance in Orca were mapped as Quantitative Trait Loci (QTLs) to chromosomes 4 (4H) and 7 (5H) (Hayes et al., 1996). Orca is resistant to Barley Yellow Dwarf Virus (BYDV). On a 1 - 9 scale (1 = resistant, 9 = susceptible) Orca received a mean symptom score of 1.7 in a test for reaction to the PAV isolate of BYDV conducted by A. Comeau (Agriculture Canada, Quebec, Canada). In the same test, the resistant parent (Bowman-derivative) received a score of 1.3 and the susceptible parent (Calicuchima-sib) a score of 8.2. BYDV resistance mapped to chromosome 3 (3H). This chromosome location corresponds to published reports on the location of the Ryd2 locus (Collins et al., 1996).

Orca was tested under both irrigated and dryland conditions in Oregon, Washington, and Idaho. It was also tested in the Western Regional Spring Barley Nursery (WRSBN) in 1997 and 1998. Orca has the highest yield potential under irrigated conditions. The yield of Orca was 5814 kg ha^-1, a 7% advantage over "Harrington" (the North American malting barley standard) and a 4% disadvantage relative to "Baronesse" (the most popular feed variety in the Pacific Northwest USA), in 21 station-years of irrigated tests. Averaged over 30 station-years of dryland tests, the yield of Orca was 4369 kg ha^-1, similar to Harrington and 17% lower than Baronesse. "Steptoe" is the feed barley check in the WRSBN. The yield of Orca was 5168 kg ha^-1 , a 1% disadvantage relative to Steptoe and a 4% advantage over Harrington, averaged over 23 station-years in the WRSBN. Orca has large, plump seeds and high test weight. In 10 station-years of dryland and 12 station-years of irrigated tests, the average percentages of plump seed (seeds remaining on a 2.4 mm slotted sieve) were 97 and 96, respectively. These represent advantages over Harrington of 22% (dryland) and 10% (irrigated). The advantages over Baronesse were 20% (dryland) and 9% (irrigated). The percentage of plump seed of Orca was 93%, a 13% advantage over Steptoe and a 20% advantage over Harrington, averaged over 17 station-years in the WRSBN. In 30 station-years of dryland and 19 station-years of irrigated tests, respectively, the average test weight of Orca was 67 kg hL^-1. This represents a 3% advantage over Harrington and performance comparable to Baronesse. Averaged over 21 station-years in the WRSBN, the test weight of Orca was 66 kg hL^-1, an 10% advantage over Steptoe and a 2% advantage over Harrington. Orca is earlier, somewhat taller, and more lodging-resistant than Harrington and Baronesse under irrigated and dryland conditions. In 16 station-years of dryland and irrigated tests, the average Julian heading dates of Orca, Harrington, and Baronesse were 173, 179, and 179 d respectively. In 19 station-years of testing in the WRSBN, the average Julian heading date of Orca was 175 d, as compared to 176 d for Steptoe and 180 d for Harrington. Averaged over 29 station-years of dryland and irrigated tests, the average plant heights of Orca, Harrington, and Baronesse were 86, 85, 83 cm, respectively. In 20 station-years of testing in the WRSBN, the plant height of Orca was 87 cm, as compared to 85 cm for Steptoe and 87 cm for Harrington. Averaged over 13 station-years of dryland and irrigated tests, the average lodging percentages (on a plot basis) for Orca, Harrington, and Baronesse were 25, 48, and 41%, respectively. Orca has some malting quality and was entered into the American Malting Barley Association Pilot Scale Malting Program. It was not advanced in this program due to its high enzyme properties.

Breeder and Foundation seed will be maintained by the Washington State Crop Improvement Association. Seed for experimental purposes may be obtained from the corresponding author.

P.M. HAYES*, A.E. COREY, R. DOVEL, R. KAROW, C.MUNDT, K. RHINART, and H. VIVAR (6)