'Ripper' Winter Wheat
	Ripper Field Plot Orchard, Colorado June 2006	Ripper Field Plot Julesburg, Colorado July 2004

• High dryland yield, excellent yield stability
• Excellent milling and bread-baking characteristics
• Awned (bearded), white-chaffed, early maturing, semidwarf
• Heading about one-half day later than 'Prairie Red', three days earlier than 'Hatcher'
• Height about one inch taller than 'Prairie Red' and 'Hatcher, similar to 'Akron'
• Medium-long coleoptile, good shattering tolerance, good straw strength
• Test weight slightly below average, similar to 'Jagger' and 'Yuma'
• Grain protein content slightly below average, similar to 'Prairie Red' and 'Hatcher'
• Moderately resistant to stem rust, susceptible to both stripe and leaf rust, resistant to biotype 1 RWA, susceptible to biotype 2 RWA, moderately susceptible to wheat streak mosaic virus

Description

'Ripper' hard red winter wheat was developed by the Colorado Agricultural Experiment Station and released to seed producers in August 2006. Ripper was released based on its superior adaptation under non-irrigated production in eastern Colorado and its' superior bread baking quality characteristics. 

Ripper is an awned, white-chaffed, early maturing, semidwarf hard red winter wheat (Table 1). Ripper is early maturing, 140.5 days to heading from 1 January, and is 0.7 days later than Prairie Red, 3.2 days earlier than 'Hatcher', and 5.2 days earlier than 'Prowers 99'. Plant height of Ripper is short (24.0 inches), and is 1.1 inch taller than Prairie Red and Hatcher (22.9 inches) and 2.6 inches shorter than Prowers 99. Coleoptile length of Ripper (84.1 mm, n=8 observations) is longer than that of Prairie Red (82.9 mm) and Hatcher (76.9 mm) but shorter than that of Prowers 99 (99.2 mm). Shattering tolerance of Ripper is good (3.7 score, 1=no shatter to 9=severe shatter, n=3 observations), slightly greater than that of Prairie Red (4.0 score), similar to that of Hatcher (3.7 score), and better than that of 'Jagger' (6.3 score) and Jagalene (7.7 score). Under non-irrigated conditions, the straw strength of Ripper was good (2.7 score, 1=erect to 9=flat scale, n=3 observations), slightly less than that of Prairie Red and Hatcher (2.0 score), similar to that of Ankor (2.7 score), and better than that of Prowers 99 (5.3 score).

Selection History

Ripper was selected from the cross 'CO940606/TAM107R-2' made in 1996. CO940606 is an unreleased sib-selection of KSWGRC29, a germplasm release from Kansas State University with the pedigree PI220127/P5//'TAM-200'/KS87H66. TAM107R-2 is an unreleased sib-selection of the hard red winter wheat cultivar 'Prairie Red'.

Ripper was selected in 2000 as an F3:4 line following early generation advanced from the F2 to the F3 generations using the bulk breeding procedure. Ripper was assigned experimental number CO00016 and evaluated in non-replicated preliminary yield trials in 2001, replicated advanced yield trials in 2002, replicated statewide variety trials from 2003 to 2006, and the Southern Regional Performance Nursery (SRPN) in 2004 and 2005. Seed purification of Ripper was done by visual identification and manual removal of tall and red-chaffed off-types from bulk seed increases. Breeder seed (F3:10) was grown in 2005 under irrigation in Colorado. 

Yield Performance

Ripper was tested at 32 trial locations of the Colorado Dryland Uniform Variety Performance Trial (UVPT; Table 2) during 2003 (6 locations), 2004 (5 locations), 2005 (10 locations), and 2006 (11 locations). Mean grain yields of Ripper (39.9 bu/a) were higher than those of all other entries tested including Hatcher (39.0 bu/a), Prairie Red (35.7 bu/a), Ankor (35.5 bu acre), and Prowers 99 (33.0 bu acre). Average grain volume weight of Ripper (57.5 lb/bu) was lower than that of Hatcher (58.4 lb/bu) and Prairie Red (58.0 lb/bu), similar to that of 'Yuma' and Jagger (57.6 lb/bu), and greater than that of 'Bond CL' (57.6 lb/bu).

Ripper was tested at five locations of the Colorado Irrigated Variety Performance Trial (IVPT; Table 3) during 2004 (two locations) and 2005 (three locations). In these trials, Ripper (89.2 bu/a) had a lower mean grain yield than that of Bond CL (99.0 bu/a), Hatcher (94.5 bu/a), and Yuma (93.0 bu/a), but a higher mean yield than that of Prairie Red (81.7 bu/a). Average grain volume weight of Ripper (57.6 lb/bu) was lower than that of Hatcher (59.6 lb/bu), Bond CL (58.3 lb/bu), and Yuma (58.5 lb/bu) but greater than that of Prairie Red (56.8 lb/bu). The straw strength of Ripper in these irrigated trials was good (2.0 score, 1=erect to 9=flat scale, n=3 observations), slightly weaker than that of Yuma (1.7 score) but stronger than those of Bond CL (4.0 score) and Hatcher (5.0 score).

Disease and Insect Resistance

On the basis of evaluations through the USDA Regional Testing Program, Ripper is moderately resistant to stem rust and susceptible to leaf rust. Based on natural field infection in Colorado, Ripper is susceptible to stripe rust. Based on cooperative evaluations through the USDA Regional Testing Program, Ripper is moderately susceptible to wheat streak mosaic virus, susceptible to the Great Plains Biotype of Hessian fly, and susceptible to greenbug Biotype E. Ripper is resistant to Russian wheat aphid Biotype 1 and susceptible to Russian wheat aphid Biotype 2. Resistance to Russian wheat aphid Biotype 1 in Ripper is conditioned by the Dn4 resistance gene from the TAM 107R-2 parent, the resistance gene from the CO940606 parent (originating from PI 220127), or both.

End-Use Quality Characteristics

Milling and bread baking characteristics of Ripper were determined from one multi-location composite grain sample in 2002 and six single-location evaluations in 2004 and 2005 (Table 4). Above, Ankor, and Hatcher were used as checks in these evaluations.

Values for milling-related variables were generally superior for Ripper compared to the three check entries. On the basis of Single Kernel Characterization System (SKCS) analysis, Ripper had higher kernel weight than Above, Hatcher, and Ankor; higher SKCS kernel diameter than Above, Hatcher, and Ankor; and lower SKCS kernel hardness index than Ankor, Hatcher, and Above. Ripper had higher Quadromat Senior flour extraction than Above, Hatcher, and Ankor and lower wheat ash than Hatcher, Above, and Ankor.

Values for baking-related variables were generally superior for Ripper compared to the three check entries. Ripper had similar grain protein content as Hatcher, Above, and Ankor. In mixograph tests optimized for water absorption, Ripper had similar water absorption as Above, Hatcher, and Ankor; lower tolerance score than Hatcher and higher than Ankor and Above; and shorter mixing time than Hatcher and Ankor and longer than Above. In straight-grade pup loaf baking tests, Ripper had higher bake water absorption than Hatcher, Ankor, and Above; similar bake mixing time as Ankor and longer than Above and shorter than Hatcher; larger pup loaf volume than Ankor, Above, and Hatcher; and higher loaf crumb grain score than Ankor, Hatcher, and Above.

Development Team

Scott D. Haley, Jerry J. Johnson, Frank B. Peairs, James S. Quick, John A. Stromberger, Sally R. Clayshulte, Hayley Miller, Emily Heaton, Jeff B. Rudolph, and Bradford W. Seabourn

Affiliations

• S.D. Haley, J.J. Johnson, J.S. Quick, J.A. Stromberger, S.R. Clayshulte, J. Butler, H. Miller, E. Heaton, Soil and Crop Sciences Dep., Colorado State Univ., Fort Collins, CO 80523
• F.B. Peairs, and J.B. Rudolph, Bioagricultural Sciences and Pest Management Dep., Colorado State Univ., Fort Collins, CO 80523
• B. W. Seabourn, USDA-ARS-GMPRC-GQSRU, 1515 College Ave., Manhattan, KS 66502-2736

References and Notes

Breeder seed of Ripper will be maintained by the Colorado Agricultural Experiment Station. Hatcher has been submitted for U.S. Plant Variety Protection under P.L. 91-577 with the certification option.

Acknowledgements

Ripper was developed with financial support from Colorado Agric. Exp. Stn. Projects 795 and 646, the Colorado Wheat Administrative Committee, and the Colorado Wheat Research Foundation.