Crop ScienceVolume 45, Issue 4 p. 1666-1667 Registrations of Germplasm Registration of Star Lake Indian Ricegrass Germplasm T.A. Jones, Corresponding Author T.A. Jones tomjones@cc.usu.edu USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300 Corresponding author (tomjones@cc.usu.edu)Search for more papers by this authorD.C. Nielson, D.C. Nielson USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Search for more papers by this authorS.L. Caicco, S.L. Caicco Formerly USDI-BLM, currently U.S. Fish and Wildlife Service, 1340 Financial Boulevard, Suite 234, Reno, NV, 89502Search for more papers by this authorG.A. Fenchel, G.A. Fenchel USDA-NRCS, 1036 Miller Street, S.W., Los Lunas, NM, 87031Search for more papers by this authorS.A. Young, S.A. Young Utah Crop Improvement Association, Utah State Univ., 4820 Old Main Hill, Logan, UT, 84322Search for more papers by this author T.A. Jones, Corresponding Author T.A. Jones tomjones@cc.usu.edu USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300 Corresponding author (tomjones@cc.usu.edu)Search for more papers by this authorD.C. Nielson, D.C. Nielson USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Search for more papers by this authorS.L. Caicco, S.L. Caicco Formerly USDI-BLM, currently U.S. Fish and Wildlife Service, 1340 Financial Boulevard, Suite 234, Reno, NV, 89502Search for more papers by this authorG.A. Fenchel, G.A. Fenchel USDA-NRCS, 1036 Miller Street, S.W., Los Lunas, NM, 87031Search for more papers by this authorS.A. Young, S.A. Young Utah Crop Improvement Association, Utah State Univ., 4820 Old Main Hill, Logan, UT, 84322Search for more papers by this author First published: 01 July 2005 https://doi.org/10.2135/cropsci2004.0469 Registration by CSSA. Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume45, Issue4July–August 2005Pages 1666-1667 RelatedInformation

(Roem. & Schult.) Barkworth] (Reg. no. GP-91, PI tion.SeedthroughtheG5generationwillbeeligibleforcertifi-636100)wasreleased1June2004asaselectedclass,genetically cation, but sale of Star Lake seed beyond G5 is prohibited tomanipulated track, pre-variety germplasm. This class of pre- limit genetic shift. Small quantities of seed will be providedvarietygermplasmiseligibleforseedcertificationunderguide- toresearchersonrequesttothecorrespondingauthor.Appro-lines developed by the Association of Official Seed Certifying priate recognition should be made if this material contributesAgencies (2001). This alternative release procedure is being to the development of a new breeding line or cultivar.utilized because propagation material of specific ecotypes isneeded for ecosystem restoration, potential for immediate T.A. Jones,* D.C. Nielson, S.L. Caicco,use is high, and potential for commercial use beyond specific G.A. Fenchel, and S.A. Youngrestoration and reclamation objectives is probably limited(Young, 1995). Participating in the release are the USDA-

Crop ScienceVolume 44, Issue 5 p. 1879-1880 Registrations of Germplasms Registration of Fish Creek Bottlebrush Squirreltail Germplasm T.A. Jones, Corresponding Author T.A. Jones [email protected] USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Corresponding author ([email protected])Search for more papers by this authorD.C. Nielson, D.C. Nielson USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Search for more papers by this authorS.R. Larson, S.R. Larson USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Search for more papers by this authorD.A. Johnson, D.A. Johnson USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Search for more papers by this authorT.A. Monaco, T.A. Monaco USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Search for more papers by this authorS.L. Caicco, S.L. Caicco U.S. Fish and Wildlife Service, 1340 Financial Blvd., Suite 234, Reno, NV, 89502Search for more papers by this authorD.G. Ogle, D.G. Ogle USDA-NRCS, 9173 West Barnes Dr., Suite C, Boise, ID, 83709Search for more papers by this authorS.A. Young, S.A. Young Utah Crop Improvement Assoc., Utah State Univ., Logan, UT, 84322-4820Search for more papers by this author T.A. Jones, Corresponding Author T.A. Jones [email protected] USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Corresponding author ([email protected])Search for more papers by this authorD.C. Nielson, D.C. Nielson USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Search for more papers by this authorS.R. Larson, S.R. Larson USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Search for more papers by this authorD.A. Johnson, D.A. Johnson USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Search for more papers by this authorT.A. Monaco, T.A. Monaco USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Search for more papers by this authorS.L. Caicco, S.L. Caicco U.S. Fish and Wildlife Service, 1340 Financial Blvd., Suite 234, Reno, NV, 89502Search for more papers by this authorD.G. Ogle, D.G. Ogle USDA-NRCS, 9173 West Barnes Dr., Suite C, Boise, ID, 83709Search for more papers by this authorS.A. Young, S.A. Young Utah Crop Improvement Assoc., Utah State Univ., Logan, UT, 84322-4820Search for more papers by this author First published: 01 September 2004 https://doi.org/10.2135/cropsci2004.1879Citations: 7 Registration by CSSA. Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Citing Literature Volume44, Issue5September–October 2004Pages 1879-1880 RelatedInformation

Crop ScienceVolume 44, Issue 3 p. 1031-1031 Registration of Germplasm Registration of Cucharas Green Needlegrass Germplasm T.A. Jones, Corresponding Author T.A. Jones tomjones@cc.usu.edu USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Corresponding author (tomjones@cc.usu.edu)Search for more papers by this authorD.C. Nielson, D.C. Nielson USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Search for more papers by this authorS.A. Young, S.A. Young Utah Crop Improvement Association, Utah State Univ., Logan, UT, 84322-4820Search for more papers by this author T.A. Jones, Corresponding Author T.A. Jones tomjones@cc.usu.edu USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Corresponding author (tomjones@cc.usu.edu)Search for more papers by this authorD.C. Nielson, D.C. Nielson USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Search for more papers by this authorS.A. Young, S.A. Young Utah Crop Improvement Association, Utah State Univ., Logan, UT, 84322-4820Search for more papers by this author First published: 01 May 2004 https://doi.org/10.2135/cropsci2004.1031 Registration by CSSA. Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Volume44, Issue3May–June 2004Pages 1031-1031 RelatedInformation

Crop ScienceVolume 44, Issue 3 p. 1031-1032 Registration of Germplasm Registration of Ribstone Indian Ricegrass Germplasm T.A. Jones, Corresponding Author T.A. Jones tomjones@cc.usu.edu USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Corresponding author (tomjones@cc.usu.edu)Search for more papers by this authorD.C. Nielson, D.C. Nielson USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Search for more papers by this authorS.A. Young, S.A. Young Utah Crop Improvement Association, Utah State Univ., Logan, UT, 84322-4820Search for more papers by this authorA. Phan, A. Phan Ducks Unlimited-Canada, 1255 Clarence Ave., Winnipeg, MB, R3T 1T4Search for more papers by this author T.A. Jones, Corresponding Author T.A. Jones tomjones@cc.usu.edu USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Corresponding author (tomjones@cc.usu.edu)Search for more papers by this authorD.C. Nielson, D.C. Nielson USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Search for more papers by this authorS.A. Young, S.A. Young Utah Crop Improvement Association, Utah State Univ., Logan, UT, 84322-4820Search for more papers by this authorA. Phan, A. Phan Ducks Unlimited-Canada, 1255 Clarence Ave., Winnipeg, MB, R3T 1T4Search for more papers by this author First published: 01 May 2004 https://doi.org/10.2135/cropsci2004.1031a Registration by CSSA. Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Volume44, Issue3May–June 2004Pages 1031-1032 RelatedInformation

Squirreltail (Elymus elymoides, E. multisetus) is a complex of 5 taxa whose systematic interrelationships are uncertain. Our objectives were to determine whether the 3 taxa studied here, Elymus elymoides ssp. elymoides, E. elymoides ssp. brevifolius, and E. multisetus, can be distinguished by several ecological and physiological traits and whether geographical origin is correlated with these traits across accessions within taxa. A multivariate principal component analysis of materials collected in the 10 contiguous western states successfully distinguished taxa, but no pair of the 3 taxa appeared to be more ecologically similar than any other pair. Elymus elymoides ssp. elymoides, which prevails in the semi-arid cold desert, was shortest and exhibited the lowest total plant dry-matter, earliest phenology, and lowest seed mass. Elymus elymoides ssp. brevifolius, which prevails in the Rocky Mountains, exhibited slowest emergence, highest specific root length, lowest nitrate reductase activity, and lowest root-to-shoot ratio. Elymus multisetus, which is most common in areas with relatively warm springs, exhibited fastest emergence (particularly from deep seeding), greatest root length, and greatest root-to-shoot ratio. Elymus elymoides ssp. brevifolius accessions clustered into 3 groups: late-maturing high-seed mass accessions originating in Colorado, New Mexico, and Arizona (Group A), early-maturing low-seed mass accessions originating in Colorado and Utah (Group B), and intermediate-maturing low-seed mass accessions originating in the Snake River Plain of southern Idaho (Group C). The ecologically distinct subspecies and groups within ssp. brevifolius are indicative of the highly ecotypic nature of the squirreltails, suggesting that restoration practitioners should match site with genetically and ecologically appropriate plant material for these species.

P-7 bluebunch wheatgrass [Pseudoroegneria spicata (Pursh) A. Löve] germplasm (Reg. no. GP-7, PI 619629) was released 28 Feb. 2001 as a selected class of Certified seed (genetically manipulated track). This class of prevariety germplasm is eligible for seed certification under guidelines developed by the Association of Seed Certifying Agencies (2001). Participating in the release are USDA-ARS and the Utah Agricultural Experiment Station. P-7 is a multiple-origin polycross generated by intermating 23 open-pollinated, native-site collections and two cultivars from Washington, Oregon, Nevada, Utah, Idaho, Montana, and British Columbia. Breeder seed of P-7 was bulked across the 25 populations in direct proportion to their seed yield in 1995 in a replicated test at the Utah State University Blue Creek Farm, Box Elder County, UT (5). Two of the populations are the cultivars Whitmar and Goldar (both originating in southeastern Washington), released by the USDA-SCS in 1946 and 1989, respectively (3; 2). Whitmar is an awnless cultivar developed from a population collected near Colton, Whitman County, WA, and Goldar is an awned cultivar developed from a population collected near Anatone, Asotin County, WA. Nine of the remaining populations were collected by T.A. Jones (PI 537368, Pollock, ID; PI 537370, Riggins, ID; PI 598821, Wawawai Park, WA; PI 537374, Steptoe Butte, WA; PI 537375, Durkee, OR; PI 537378, Lone Mountain Junction, NV; PI 516185, Seneca, OR; PI 537388, Dayton, WA; PI 563870, Green Canyon, UT), seven by K.H. Asay (PI 563872, New Meadows, ID; PI 563867, Colton, WA; PI 563868, Wawawai Road, WA; PI 563874, Wawawai Park, WA; PI 562050, Wawawai Park, WA; PI 598816, Connell, WA; PI 562056, Lind, WA), and seven were obtained from miscellaneous sources (PI 595192, Wawawai Road, WA; PI 595193, Almota Road, WA; PI 595196, Darby, MT; PI 236670, Slocan, BC; P-3, Grande Ronde River, OR; P-5, unknown; KJ-10, Salina Canyon, UT). Twenty-four of the constituent populations are diploid (2n = 2x = 14) and one (PI 537374) is tetraploid (2n = 4x = 28). The inclusion of the tetraploid PI 537374 in the polycross was inadvertent. The representation of this tetraploid is expected to decline dramatically through generations of seed increase. Therefore, P-7 can be considered to be predominately diploid, the dominant ploidy level of bluebunch wheatgrass. P-7 is intended to provide genetic diversity within a single germplasm for semiarid to mesic sites where bluebunch wheatgrass was an original component of the vegetation. Bluebunch wheatgrass is a cross-pollinated species widely distributed in the Intermountain West. The proportion of total nucleotide variation among the two cultivars of this species (GS = dA/dXY) was 0.07 (5), an order of magnitude lower than reported among northern California populations of self-pollinating purple needlegrass [Nassella pulchra (Hitchc.) Barkworth] (6). P-7 was developed to reflect the large proportion of genetic variation packaged within natural bluebunch wheatgrass populations, e.g., 93% within Whitmar and Goldar, as well as the small proportion of genetic variation typically found between natural populations, e.g., 7% between Whitmar and Goldar (5). Sixteen of the P-7's 25 component populations are predominately awned and 9 are predominately awnless (5). Because the awnless state is dominant and the awned state is recessive in bluebunch wheatgrass and its relatives (4), P-7 individuals are predominately awnless. More amplified fragment length polymorphic (AFLP) alleles (99) were found to be unique to P-7, i.e., present in P-7 but absent in Goldar and Whitmar, than were found to be unique to Whitmar (59) or Goldar (49) (5). P-7 also had fewer fixed loci (233) than Whitmar (385) or Goldar (318). Overall nucleotide-sequence diversity [π ± SE(1000)], i.e., within-population variation, was greater for P-7 (38.7 ± 1.6) than for Whitmar (34.2 ± 1.5) or Goldar (33.9 ± 1.5). Average net nucleotide-sequence divergence (dA), i.e., between-population variation, was 0.3 ± 0.2 between P-7 and Goldar, 1.3 ± 0.2 between P-7 and Whitmar, and 2.6 ± 0.3 between Goldar and Whitmar. Therefore, P-7 is genetically intermediate between the two cultivars but more similar to Goldar than to Whitmar. G-0 (the separate 25 populations), G-1 (first intermating), and G-2 (second intermating) generations will be maintained by the USDA-ARS Forage and Range Research Laboratory, Logan, UT. G-2 seed will be made available to growers for production of G-3 and G-4 generations of seed (third and fourth intermating) by the Utah Crop Improvement Association. Sale of P-7 seed beyond generation G-4 is expressly prohibited to limit genetic shift. Small quantities of seed will be provided to researchers upon request to the corresponding author.

Session 4 Conventional and Novel Methodologies for Plant Improvement Lethbridge, Alberta, Canada X Acc:641 beardless wildrye of Jamieson, Oregon, USA), its reciprocal (L4PX-3R), L4PX-5 (‘Trailhead’ Basin wildrye of Roundup, Montana, USA X Acc:641 beardless wildrye), and its reciprocal (L4PX-5R), using a modified ryegrass (Lolium spp.) procedure (Arnold J.P. vanWijk of D.J. van der Have B.V. [Rilland, The Netherlands], pers. comm.). Seedlings with radicles just emerging were placed into a 5-cm petri dish lined with a single disk of Whatman #2 filter paper soaked with 0.3 ml of 0.2% colchicine solution. Seedlings were arranged to ensure radicle contact with the filter paper. After 2 h in the dark at 30°C, seedlings were gently rinsed twice with water and plated on moist blotter paper before planting in the greenhouse.

Indian ricegrass (Achnatherum hymenoides [Roem. & Schult.] Barkw. = Oryzopsis hymenoides [Roem. gr Schult.] Ricker = Stipa hymenoides Roem. & Schult.) may buffer its seed banks over time via morphological (lemma and palea) and physiological (seed coat) seed dormancy. However, Indian ricegrass seed dormancy has usually not been examined from a genetic perspective. Because a positive relationship between seed dormancy and seed size has long been noted within Indian ricegrass populations, we wanted to determine if genetic variation for seed dormancy was present among seed morphs. We also wanted to determine if genetic variation for seed dormancy was present in material without polymorphism. The T-593 population from McKinley Co., N.M., has 3 seed morphs produced on genetically distinct plants,'elongate' (2.24 mg/seed), 'globose' (3.00 mg/seed), and 'jumbo' (8.70 mg/seed). Following a 3-week prechill, elongate seed showed higher germination (66%) than globose seed (20%) over 6 tests (pairs of seed lots), while jumbo seed did not germinate without scarification. Jumbo seed had thicker (181 mu g) lemmas than globose (93 mu g) or elongate (52 pg) seed. Individual plants of the nonpolymorphic cultivar, Rimrock, were selected for high or low germination following a 3-week prechill. The spring following seed harvest, germination with prechill was greater for progeny lines of the high-germination selections (45.5%) than low-germination selections (3.8%) with Rimrock intermediate (11.8%). This heritable difference in germination was accompanied by only small differences in lemma and palea thickness and no difference in seed mass. Genetic variation in seed dormancy may be found both between morphs (interpreted as variation for morphological dormancy) and within morphs (interpreted as variation for physiological dormancy). Genetic variation for seed dormancy can be as great within a population as between populations.

Crop ScienceVolume 38, Issue 1 cropsci1998.0011183X003800010064x p. 286-286 Registration of Germplasm Registration of Sand Hollow Squirreltail Germplasm T. A. Jones, Corresponding Author T. A. Jones tomjones@cc.usu.edu USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Corresponding author (tomjones@cc.usu.edu).Search for more papers by this authorD. C. Nielson, D. C. Nielson USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Search for more papers by this authorD. G. Ogle, D. G. Ogle USDA-NRCS, 3244 Elder St., Rm. 124, Boise, ID, 83705-4711Search for more papers by this authorD. A. Johnson, D. A. Johnson USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Search for more papers by this authorS. A. Young, S. A. Young Utah Crop Improvement Association, Utah State Univ., Logan, UT, 84322-4820Search for more papers by this author T. A. Jones, Corresponding Author T. A. Jones tomjones@cc.usu.edu USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Corresponding author (tomjones@cc.usu.edu).Search for more papers by this authorD. C. Nielson, D. C. Nielson USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Search for more papers by this authorD. G. Ogle, D. G. Ogle USDA-NRCS, 3244 Elder St., Rm. 124, Boise, ID, 83705-4711Search for more papers by this authorD. A. Johnson, D. A. Johnson USDA-ARS Forage and Range Research, Utah State Univ., Logan, UT, 84322-6300Search for more papers by this authorS. A. Young, S. A. Young Utah Crop Improvement Association, Utah State Univ., Logan, UT, 84322-4820Search for more papers by this author First published: 01 January 1998 https://doi.org/10.2135/cropsci1998.0011183X003800010064xCitations: 9AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume38, Issue1January–February 1998Pages 286-286 RelatedInformation

Crop ScienceVolume 38, Issue 2 cropsci1998.0011183X003800020057x p. 539-540 Registration of Cultivars Registration of ‘Rimrock’ Indian Ricegrass T. A. Jones, Corresponding Author T. A. Jones [email protected] USDA-ARS Forage and Range Res. Lab., Logan, UT, 84322-6300Corresponding author ([email protected]).Search for more papers by this authorM. E. Majerus, M. E. Majerus USDA-NRCS Plant Materials Center, Rt. 1, Box 1189, Bridger, MT, 59014-9718Search for more papers by this authorJ. G. Scheetz, J. G. Scheetz USDA-NRCS Plant Materials Center, Rt. 1, Box 1189, Bridger, MT, 59014-9718Search for more papers by this authorL. K. Holzworth, L. K. Holzworth USDA-NRCS, 10 E. Babcock St., Bozeman, MT, 59715 North Carolina State Univ., Raleigh, NC, 27695Search for more papers by this authorD. C. Nielson, D. C. Nielson USDA-ARS Forage and Range Res. Lab., Logan, UT, 84322-6300 North Carolina State Univ., Raleigh, NC, 27695Search for more papers by this author T. A. Jones, Corresponding Author T. A. Jones [email protected] USDA-ARS Forage and Range Res. Lab., Logan, UT, 84322-6300Corresponding author ([email protected]).Search for more papers by this authorM. E. Majerus, M. E. Majerus USDA-NRCS Plant Materials Center, Rt. 1, Box 1189, Bridger, MT, 59014-9718Search for more papers by this authorJ. G. Scheetz, J. G. Scheetz USDA-NRCS Plant Materials Center, Rt. 1, Box 1189, Bridger, MT, 59014-9718Search for more papers by this authorL. K. Holzworth, L. K. Holzworth USDA-NRCS, 10 E. Babcock St., Bozeman, MT, 59715 North Carolina State Univ., Raleigh, NC, 27695Search for more papers by this authorD. C. Nielson, D. C. Nielson USDA-ARS Forage and Range Res. Lab., Logan, UT, 84322-6300 North Carolina State Univ., Raleigh, NC, 27695Search for more papers by this author First published: 01 March 1998 https://doi.org/10.2135/cropsci1998.0011183X003800020057xCitations: 11AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL No abstract is available for this article.Citing Literature Volume38, Issue2March–April 1998Pages 539-540 RelatedInformation

We compared the effectiveness of generalist predators in reducing populations of the Russian wheat aphid, Diuraphis noxia (Mordvilko), on range grasses that differ in leaf architecture. Crested wheatgrass, Agropyron desertorum, produces relatively broad leaves and, like wheat, provides aphids with rolled leaves as potential refuges from natural enemies; Indian ricegrass, Oryzopsis hymenoides, bears linear, involute leaves that are usually too narrow to permit aphid aggregations within leaf rolls. We established aphid populations on each host and then introduced either neonate larvae of the lacewing Chrysoperla plorabunda (Fitch) or adults of the ladybird beetle Propylea quatuordecimpunctata L. On seedlings, there was an interaction between the effects of predator species and host-plant species; beetles were less effective on crested wheatgrass than on Indian ricegrass, but lacewings eliminated or nearly eliminated aphid populations on both hosts. On whole plants in the field, both predators tended to be more effective on Indian ricegrass than on crested wheatgrass. In all experiments, lacewing larvae were superior to beetles in causing extinction of aphid populations. These results are consistent with behavioral observations of foraging predators, and suggest that the host-plant effects on the 3rd trophic level can depend on predator species as well as plant stage.

Bluebunch wheatgrass [Pseudoroegneria spicata (Pursh) A. Love] has long been noted for poor tolerance to grazing during culm elongation in the spring. Bluebunch wheatgrass is an autoploid series of diploids (2x) and tetraploids (4x). In the mid-1980s, a group of populations were found to be allotetraploid and are now commonly referred to as Snake River wheatgrass. Relative grazing tolerance of 2x and 4x bluebunch wheatgrass and of Snake River wheatgrass is unknown. This study evaluated the effect of multiple defoliation on these grasses to simulate one consequence of grazing, removal of photosynthetic tissue. Fifteen entries representing the three taxa were established at North Logan, UT, on a Millville silt loam (coarse-silty, carbonatic, mesic Typic Rendolls; 2-4% slope) during 1988. Seedlings were vegetatively propagated into two clones apiece and transplanted adjacent to one another; one clone was subjected to multiple defoliation and the other served as an undefoliated control. Multiple defoliation at 10 cm was applied from late spring to midsummer from 1990 to 1992 at 4-wk intervals and dry matter yield was measured in late fall 1991, early spring 1992, late fall 1992, and late spring 1993. We used the defoliated-to-control ratio of plant response to estimate defoliation tolerance. The defoliated-to-controI ratio for dry matter yield of Snake River wheatgrass (0.17 and 0.38 in late fall 1991 and early spring 1992, respectively) was greater than for 4x (0.06 and 0.18) or 2x (0.06 and 0.19) bluebunch wheatgrasses after the first year of multiple defoliation. The defoliated-to-contro1 ratio for dry matter yield did not differ among taxa in late fall 1992, but the ratios for Snake River wheatgrass (0.20) and 4x bluebunch wheatgrass (0.21) were both greater than for 2x bluebunch wheatgrass (0.13) in late spring 1993. Less variation was seen among Snake River than bluebunch wheatgrass entries. Because Snake River wheatgrass had both higher yield and greater defoliation tolerance than bluebunch wheatgrass, Snake River wheatgrass is more likely to survive defoliation over the long term.

We measured the grazing preference of 3 castrated male Rocky Mountain elk (Cervus elaphus nelsoni) for 2 crested (Agropyron desertorum [Fischer ex Link] Schultes), 5 thickspike (Elymus lanceolatus ssp. lanceolatus [Scribner &J.G. Smith] Gould), 3 Snake River (proposed name E. lanceolatus ssp. wawawaiensis), and 2 bluebunch wheatgrass (Pseudoroegneria spicata [Pursh] A. Love) entries. Number of bites and visits were highly correlated in early May (r2=0.77) and late May (r2=0.83). 'Critana' and 'Elbee' thickspike and 'Hycrest' and 'Nordan' crested wheatgrasses can be recommended for seedings for elk spring grazing where these grasses are adapted.

Greenhouse and field experiments were conducted to determine whether host-plant species affects the ability of a generalist predator to reduce populations of the Russian wheat aphid, Diuraphis noxia (Mordvilko). Aphid colonies were allowed to develop on six species of cool-season grasses for 10 days, after which half of the plants received five neonate larvae of the common green lacewing, Chrysoperla carnea (Stephens). Lacewing larvae substantially reduced aphid density on both grass seedlings (in the greenhouse) and mature plants (in the field). The level of control varied among grass species, however. Aphid populations were reduced to zero or near zero on two slender-leaved grasses (Indian ricegrass and bluebunch wheatgrass), but were maintained at moderate densities on a pubescent cultivar of intermediate wheatgrass. Mechanisms underlying this tri-trophic interaction are unknown, but plant morphology may play an important role because of the ''leaf-galling'' habit of D. noxia.

We compared the preference of cattle for 12 entries, 2 of crested wheatgrass [Agropyron desertorum (Fischer ex Link) Schultes], 5 of thickspike wheatgrass [Elymus lanceolatus (Scribner & J.G. Smith) Gould ssp. lanceolatus], 3 of Snake River wheatgrass (proposed name E. lanceolatus spp. wawawaiensis), and 2 of blue-bunch wheatgrass [Pseudoroegneria spicata (Pursh) A. Love] in May 1989 and 1990 at Logan, Utah. Spaced plants were randomly arranged in 4 paddocks which were grazed once by 2 animals in late spring each year. Number of bites and number of visits were recorded for each entry in each paddock for the 2 animals individually. Cattle preferred Hycrest and Nordan crested wheatgrasses both years. Number of bites per plant for crested, thickspike, Snake River, and bluebunch wheatgrasses averaged 9.1, 4.3, 3.1, and 4.1, respectively, in 1989 and 6.7,3.3, 3.5, and 3.6, respectively, in 1990. Number of visits was highly correlated with number of bites across entries. Grazing preference among entries was more highly correlated with biomass score and canopy height than basal area or maturity. Cattle preferred crested wheatgrass over the native wheatgrasses tested here during the spring grazing season.

Seed dormancy is the primary factor limiting stand establishment of Indian ricegrass [Oryzopsis hymenoides (Roem. & Schult.) Ricker] in rangeland reseedings in western North America. Our objective was to determine if irrigation or bagging of plants during seed production affected dormancy of two Indian ricegrass accessions, the cultivar Paloma and the experimental population PI 478833. Bagging of inflorescences for research purposes is practiced because of susceptibility to shattering. In 1989, irrigated and nonirrigated treatments were applied, and seed was harvested on 28 July. In 1990, irrigation was applied as in 1989, but approximately half of each plant's panicles were enclosed in a brown paper bag. Seed was harvested 5 July from spring growth [seed production interval (SPI) 1], 10 August from regrowth since 7 June (SPI 2), and for Paloma unbagged only, on 10 August from regrowth since 5 July (SPI 3). In 1989, germination of Paloma relative to PI 478833 was greater (P < 0.01) with irrigation (76% versus 39%) than without (63% versus 51%). In 1990, SPI 1 irrigation and accession did not interact, but at SPI 2, germination of Paloma relative to PI 478833 was again greater (P < 0.05) with irrigation (74 versus 50%) than without (60 versus 46%). Irrigation did not affect germination of Paloma at SPI 3. In 1990, SPI 1 germination of PI 478833 relative to Paloma was greater (P < 0.01) with bagging (61% versus 40%) than without (41% versus 39%). The same trend was evident at SPI 2, where germination of PI 478833 relative to Paloma was greater (P < 0.01) with bagging (52% versus 62%) than without (44% versus 72%). Germination of Paloma was enhanced by irrigation, while germination of PI 478833 was favored by bagging. Researchers should be aware that these environmental factors may interact with accession to affect seed dormancy in Indian ricegrass.

We conducted a series of field experiments to assess whether cool-season grasses were important in maintaining populations of the Russian wheat aphid, Diuraphis noxia (Mordvilko), between the summer harvest and fall sowing of winter cereals. All six grass species in a common garden in northern Utah supported aphid population growth from May to September 1991, although aphid densities were unusually low on mature foliage in july. Under conditions of little or no plant competition, each grass species produced at least a few fall tillers before mature shoots had senesced completely and hence provided a continuous source of food for aphids. Indian ricegrass was a consistently good host and bluebunch wheatgrass was a consistently poor one, but the relative suitabilities of the six hosts varied considerably over the season. Neither plant water content nor total nitrogen was correlated with differences in aphid performance among hosts. We conducted a greenhouse experiment to compare estimates of plant quality under field and greenhouse conditions. Differences in aphid performance among hosts in the greenhouse resembled those observed in the field early in the season, but not during the critical ''oversummering'' period.

Grazing at the boot stage can severely damage stands of bluebunch wheatgrass [Pseudoroegneria spicata (Pursh) A. Love]. Snake River wheatgrass [proposed name Elymus lanceolatus ssp. wawawaiensis (Scribner & Gould) J.R. Carlson & D.R. Dewey] has recently been recognized as a taxon distinct from bluebunch wheatgrass, based on cytological data, and placed in the same species as thickspike wheatgrass [Elymus lanceolatus ssp. lanceolatus (Scribner & J.G. Smith) Gould]. Grazing tolerance of Snake River wheatgrass is unknown. This study was conducted to evaluate the effect of clipping at the boot stage on vigor of 'Secar' Snake River wheatgrass, 'Elbee' and T-21076 thickspike wheatgrass, and hybrid populations D30 (50% Snake River wheatgrass/50% thickspike wheatgrass) and D38 (75% Snake River wheatgrass/25% thickspike wheatgrass). Plots were established at North Logan, UT (mollisol) and near Stone, ID (aridisol) in 1987, clipping treatments (clipped or unclipped at the boot stage) were applied in 1988 and 1989, and treatments were compared in 1990. Regardless of spring-clipping treatment, all plants were clipped once in the summer at both locations and again in the fall at North Logan both in 1988 and 1989. Spring clipping reduced Secar dry weight 21%, spike number 27%, and plant basal area (above-ground area occupied by tillers) 17% at North Logan, while the other populations were unaffected. Spring clipping reduced dry weight 26 and 31%, spike number 37 and 36%, and plant basal area 24 and 33%, of Secar and D38, respectively, near Stone, while the other populations were unaffected. Spring clipping was more detrimental at the Stone aridisol than the North Logan mollisol site. Currently available germplasm of the rhizomatous thickspike wheatgrass appears to be more tolerant of spring clipping than that of the caespitose Snake River wheatgrass. It should be possible to make substantial genetic progress for spring-clipping tolerance in hybrid populations.

In a 4-year field study, 25 perennial triticeae grasses, representing a wide range of genomes and genome combinations, were evaluated as potential hosts for the bluegrass billbug (Sphenophorus parvulus Gyllenhal [Coleoptera: Curculionidae]). Root-sample data suggested that Russian wildrye (Psathyrostachys juncea [Fischer] Nevski) was unsuitable for billbug reproduction. Numbers of immatures varied significantly among remaining entries. Rhizomatous entries were more tolerant of billbug injury than caespitose entries. Plant mortality rates were frequently 50% or higher for self-pollinated caespitose entries with the SH genome complement (Elymus spp.). Losses to billbugs among the remaining species, particularly those with the J, N, and P genomes, were insigificant. Billbugs did not discriminate between native and introduced grasses, as resistant and susceptible entries were identified in both groups. The results obtained here may aid in selecting triticeae grasses for reseeding in areas where billbugs have damaged stands in the past.