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'Newhy' Hybrid Wheatgrass Long Range Field Planting PlanScientific Name'NewHy' hybrid wheatgrass, Elytrigia repens (L.) nevski x Pseudoroegneria spicata (PURSH) A. Love Origin and Method of DevelopmentThe parental population of the RS hybrid was initially established in 1962 (Dewey 1967). The initial 'F1' hybrid was pentaploid (2n=35), meiotically irregular, beset with chlorophyll deficiencies, and in general, had poor vegetative vigor. Although the hybrid plants were only partially fertile, adequate seeds were produced for generations to be advanced without chromosome doubling. From the 'F1' to 'F5' generation, selection was based largely on fertility (seeds/spike) and was restricted to plants with characteristics of both parental species. Plants with excessive rhizome development were excluded. More intense selection was initiated in the 'F5' generation. The objectives were to combine the vigor, productivity, salinity tolerance, and persistence of quackgrass with the drought resistance, caespitose growth habit, seed quality, and forage quality of bluebunch wheatgrass. Two 'F7' to 'F8' germplasm pools, designated RS-1 and RS-2, were released to breeders in 1980 (Asay and Dewey 1981). These two lines were morphologically similar with the exception the RS-2 was slightly more rhizomatous than RS-1. Two additional cycles of selection were completed with the combined RS-1 and RS-2 breeding populations to develop the parental lines of the 'NewHy' cultivar. DescriptionThe chromosome number of the 'NewHy' has stabilized at 2n=42 meiotic stability and good fertility has been achieved. Rate of phenological development is intermediate to the parental species and anthesis occurs from mid to late June in nurseries near Logan. The hybrid produced 560 kg of seed per ha on an irrigated site near Miles City, Montana. (Currie unpublished) Degree of rhizome development in the Rs breeding population readily responds to selection pressure (Asay and Hansen 1984). Essentially caespitose types have been derived after two cycles of selection. Rhizome development of the 'NewHy' cultivar ranges from less than 0.1 m to slightly over 1.0 m per year on range sites receiving from 33 to 38 cm annual precipitation. On these sites, over 85 percent of the plants develop rhizomes of less than 0.4 m during the season and the population averages approximately 0.3 m. Superior Characteristics, Site Adaptation, and Potential Uses'NewHy' has demonstrated excellent resistance to excess soil salinity. In trials on a saline meadow near Miles City, Montana, the hybrid was more salt tolerant than 'Garrison' creeping foxtail (Alopecurus arundinaceus), Altai wildrye (Leymus angustus), and Russian wildrye (Psathyrostachys juncea) (Currie et al. 1986). In greenhouse trials (Horton unpublished), 'NewHy' was more tolerant of salinity than intermediate wheatgrass (Thinopyrum intermedium), western wheatgrass (Pascopyrum smithii), tall fescue (Festuca arundinacea), and 'Garrison' creeping foxtail. Tall wheatgrass (Thinopyrum ponticum) was the only entry in these tests to have greater tolerance to salinity than 'NewHy'. The forage yield and quality of the RS hybrid has been evaluated on several range sites in the Intermountain West and to a lesser extent in the Great Plains. It is most productive on slightly saline or alkaline range sites receiving at least 33 cm of precipitation annually. Results from the Utah State University Experiment Station in northwest Utah are typical. Poor seed germination resulted in stands of less than 50 percent during the establishment year. Consequently, dry matter yield of the hybrid was significantly (P < 0.05) less than 'Greenar' intermediate wheatgrass and 'Hycrest' crested wheatgrass during the following season. As stands improved through tillering and rhizome development during the third and fourth years, 'NewHy' produced more forage than any of the other 16 entries included in the trial. It is noteworthy that 'NewHy', unlike its quackgrass parent, did not spread beyond its plot borders into adjacent plots. Similar trends were observed in a trail established in the foothills of the LaSal Mountains in Southern Utah, at an altitude of 1,900 m and with an annual average of 33 cm precipitation. Although initial stands were better than at Blue Creek, forage yield of 'NewHy' during the first production year was significantly less than the mean of the rest of the entries in the trial. In the two subsequent years, however, the productivity of the hybrid improved dramatically and was equivalent to the most productive entries in the trial. Quality of the RS hybrid forage was evaluated at the Blue Creek Station on six harvest dates, at three-week intervals beginning in late April. Neutral detergent fiber (NDF) of RS was 33.4 percent in April and 60 percent on the final date in August. In comparison, NDF of 'Greenar' intermediate wheatgrass was 32.8 percent in April and 63.2 percent in August. The average NDF of 'Greenar' (55.1%) was significantly higher than the hybrid (52.4%). Percent crude protein of the hybrid was significantly lower than 'Greenar' (21.5% vs 24.4%) in April; however, comparable values were obtained at the remaining five harvests. Percent crude protein of the hybrid at the six dates were: 21.5; 16.6; 11.1; 9.1; 7.6; and 6.8, respectively, with an average 12.1 percent. Although 'NewHy' begins growth early in the spring, it remains more succulent and palatable for livestock later in the growing season than most other wheatgrasses, especially on dryland range sites. In a trail in Central Utah, cattle grazed 'NewHy' in preference to all other entries in the trial including intermediate and crested wheatgrass. The hybrid recovers rapidly after grazing or defoliation and once established, it has excellent resistance to grazing pressure. 'NewHy' has been evaluated to a limited extent under irrigation. As in the range trials, problems with initial stand establishment were encountered, although these deficiencies were less pronounced under irrigation. During the second and third seasons after the year of establishment, however, the productivity of the hybrid compared favorably with other entries such as orchardgrass (Dactylis glomerata) and smooth bromegrass (Bromus inermis). Although considerable variation exists among seedlots, seed quality tends to be somewhat lower than grasses such as crested and intermediate wheatgrass. Improved seed quality continues to be a breeding objective; however, until this deficiency is corrected, it is recommended that seeding rates from 9 to 12 kg/ha (8 to 10.5 lbs/acre) be used in its areas of adaptation. It should be noted that after emergence, seedlings are vigorous and establish themselves rapidly under relatively harsh conditions. Insect ProblemsThe hybrid has shown moderate susceptibility to injury by the grass billbug (Sphenophorus parvulus) under soil and moisture conditions where this insect is a potential problem. Seed Increase and DistributionBreeders seed will be maintained by the USDA-ARS at Logan, Utah. Foundation seed will be produced from breeders seed by USDA-ARS at Logan and USDA-SCS at Los Lunus, New Mexico. Foundation seed is distributed by the Utah Crop Improvement Association and the USDA-SCS. Certified seed my be produced only from Foundation seed. For information regarding supplies of Foundation seed contact:
Because of the morphological similarity of 'NewHy' seed to that of quackgrass, protection has been applied for under the Plant Variety Protection Act of 1970. Conditions of this license specifies that 'NewHy' seed can be marketed only as a class of certified seed. Sale of non-certified seed of this protected cultivar to anyone, including neighbors or friends, is in violation of the Plant Variety Protection Act. Planting InformationCulture and Management 1In accordance with applicable practice standards and specifications as stated in Section IV of the Field Office Technical Guide. Planting SizeMinimum five (5) acres each, featured cultivar and standard of comparison entry. Seeding RateEight (8) pounds pure live seed (PLS) per acre in pure stands. Adjust accordingly for mixtures. Standard of Comparison
EvaluationHerbaceous plant performance will be requested annually for the first five (5) years and the tenth (10th) year following establishment. Standard evaluation forms will be provided. 1 Seedbed preparation, planting methods, seed placement depth, weed control, and stand establishment management. 2 Field office location managed by the respective Area Plant Materials Committees. < Back to Long Range Plans for Field Plantings Last Modified: 07/05/2007 |
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