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a Dep. of Agronomy and Horticulture, Univ. of Nebraska, Lincoln, NE 68583
b USDA-ARS and Dep. of Agronomy and Horticulture, Univ. of Nebraska, Lincoln, NE 68583
c Dep. of Plant Pathology, Univ. of Nebraska, Lincoln, NE 68583
d Dep. of Agronomy and Horticulture, West Central Research and Extension Center, Univ. of Nebraska, North Platte, NE 69101
e Dep. of Agronomy and Horticulture, Univ. of Nebraska, Lincoln, NE 68583, current address: Soil and Crop Sciences Dep., Texas A&M Univ., College Station, TX 77843
f USDA-ARS and Dep. of Plant Pathology, Univ. of Minnesota, St. Paul, MN 55108
g USDA-ARS-PSERU and Dep. of Entomology, Kansas State Univ., Manhattan, KS 66506
h USDA-ARS-PSERU and Dep. of Agronomy, Kansas State Univ., Manhattan, KS 66506
* Corresponding author (pbaenziger1{at}unl.edu).
ABSTRACT
‘Camelot’ (Reg. No. CV-1036, PI 653832) hard red winter wheat (Triticum aestivum L.) was developed cooperatively by the Nebraska Agricultural Experiment Station and the USDA–ARS and released in 2008. In addition to researchers at the releasing institutions, USDA–ARS researchers at Manhattan, KS, and St. Paul, MN, participated in the development of Camelot. Camelot was selected from the cross KS91H184/‘Arlin’ Sib//KS91HW29/3/NE91631/4/VBF0168 that was made in 1995. Camelot was selected as an F3:4 line (F3–derived line in the F4 generation) in 1999, and in 2001 it was assigned experimental line number NE01604. Camelot was released because of its superior grain yield performance, disease resistance, and end-use quality under nonirrigated production in Nebraska and adjacent states.
Abbreviations: NESVT, Nebraska State Variety Trial • NIN, Nebraska Intrastate Nursery • NNA, nearest neighbor • NRPN, Northern Regional Performance Nursery
‘Camelot’ (Reg. No. CV-1036, PI 653832) hard red winter wheat (Triticum aestivum L.) was tested under experimental line number NE01604 and was developed cooperatively by the Nebraska Agricultural Experiment Station and the USDA–ARS and released in April 2008 by the developing institutions. Camelot will be marketed through the NuPride Genetics Network, which continues its naming process based on regal names. Camelot was released because of its superior grain yield, disease resistance, and end-use quality performance under nonirrigated production in Nebraska and adjacent states.
Camelot was selected from the cross KS91H184/‘Arlin’ (PI 564246, Sears et al., 1997) Sib//KS91HW29/3/NE91631/4/VBF0168 that was made in 1995. KS91H184 is an experimental line from Kansas and is a selection from a random mating population involving CI17884 (Wells et al., 1982; as cited by Haley et al., 2005). The pedigree of KS91HW29 is 84WS164/2157. The pedigree of NE91631 is NE82761/‘Redland’ (PI502907, Schmidt et al., 1989) where the pedigree of NE82761 is CO725082 2*/‘Roughrider’ (CI17439, Erickson et al., 1977) where CO7250582 was derived from IL21183/2643//‘Lancer’ (CI13457, Schmidt et al., 1965)/3/KS62. The line VBF0168 was originally developed by Pioneer Hi-Bred International, Inc. and given to Kansas State University; however, the pedigree has been lost.
Methods
Early Generation Population Development
Camelot was developed using a bulk breeding procedure. The initial cross (made in spring 1995) and F1 plants were grown over the winter in the greenhouse and the F2 seed was harvested in bulk in May 1996. The F2 bulk generation was grown in an unreplicated breeding nursery at Mead, NE, that was planted in September 1996 and harvested in July 1997 with a small plot combine. Each F2 bulk was planted in a four-row plot with each row being 2.4 m long with 30 cm between rows. The seeding rate was 54 kg ha–1. After a mild culling selection of less than 5% to remove very poor bulks (usually based on poor winter survival, although also on poor disease resistance, extreme lateness, or lodging), F3 bulks were planted in September 1997, in an unreplicated F3 bulk nursery, each as a four-row plot that was 6.6 m long with 30 cm between rows. Of F3 populations, approximately 50% were visually selected on the basis of winter survival, disease resistance, and general agronomic appearance (mainly plant height, flowering date, standability, and visually estimated yield potential). Each selected population was advanced by random sampling of approximately 100 spikes, although especially meritorious bulks had a sample of 200 to 300 spikes selected in July 1998. Selected spikes were threshed individually and planted in a headrow nursery in September 1998. Headrow selections were planted as a single row in a four-row set that was 0.9 m long with 30 cm between rows.
Line Selection and Evaluation
On the basis of visual appraisal of uniformity and agronomic appearance, Camelot was selected from the headrow nursery as an F3:4 line in July 1999. Three lines were selected from the population. In August 1999, before planting, all headrow harvested seed was visually inspected for kernel plumpness and discoloration indicating diseased or stressed plant growth. Less than 5% of the harvested head rows were normally discarded; in this case, however, one of the three selections was discarded. In September 1999, Camelot and 1518 other headrows were advanced to an unreplicated observation nursery with replicated check cultivars ‘Alliance’ (PI 573096; Baenziger et al., 1995) planted at plot numbers ending in 25 (i.e., 15025, 15125, 15225, etc.), ‘Arapahoe’ (PI 518591; Baenziger et al., 1989) planted at plot numbers ending in 50, ‘Jagger’ (PI 593688; Sears et al., 1997a) planted at plot numbers ending in 75, and ‘2137’ (PI 592444; Sears et al., 1997b) planted at plot numbers ending in multiples of 100. The observation nursery was planted at Lincoln and Mead, NE. At Lincoln, each line was planted in a four-row plot with each row being 2.4 m long with 30 cm between rows. At Mead, each line was planted in a single row that was 2.4 m long with 30 cm between it and adjacent rows. Over the winter, all of the lines were evaluated in the greenhouse for their resistance to stem rust (caused by Puccinia graminis Pers.:Pers. f. sp. tritici Eriks & E. Henn.) using race TPMK. Four hundred twenty-seven experimental lines and 18 plots of the check cultivars were harvested in July 2000, on the basis of winter survival (determined at Mead, NE), resistance to stem rust and other diseases prevalent in the field, uniformity, general agronomic appearance (mainly plant height measured from the soil surface to the tip of the spikes, excluding the awns; flowering date measured as the number of days to when 50% of the emerged spikes had extruded anthers; standability, measured using a scale of 1 to 10, with 1 being little to 10% lodging and 10 being 100% lodged; and visually estimated grain yield potential at maturity). At harvest, the center two rows of each selected four-row plot in Lincoln were cut using a two-row sickle bar cutter and threshed using a stationary thresher (to ensure pure seed). After harvest, the actual grain yields of the visually selected experimental lines were compared to the check cultivar grain yield mean and specifically to those check cultivar plots closest to the harvested experimental line. The lowest grain yielding lines were discarded. For the remaining lines, 40 g of grain were tempered to a moisture content of 152 g H2O kg–1 grain and milled in a Brabender Junior Laboratory mill (C.W. Brabender Instruments, Inc., South Hackensack, NJ). The flour was separated from the bran using a shaker (Strand, Minneapolis, MN) at 225 rpm for 90 s with a U.S. Standard Sieve No. 70 and weighed to estimate the flour yield per 40-g sample of grain. Flour protein concentration was determined by near-infrared reflectance spectroscopy using flour samples from each plot following Method 39-70 (American Association of Cereal Chemists, 2000). Flour mixing characteristics were evaluated on a 10 g flour sample using a Mixograph (National Manufacturing Co., Lincoln, NE) according to the Approved Method 54-40 (American Association of Cereal Chemists, 2000) with a constant water absorption of 610 g H2O kg–1 of flour. Mixograph mixing time (hereafter referred to as mixing time) was determined as the time in minutes required to reach peak dough resistance. Mixograph mixing tolerance (hereafter referred to as mixing tolerance) was rated based on the comparison against standard curves in the Nebraska Wheat Laboratory using a scale from low (0) to very high tolerance (7), with higher scores indicating greater tolerance of dough to overmixing using Approved Methods 54-40 (American Association of Cereal Chemists, 2000; Baenziger et al., 2001b). Wheat lines with a mixing time of >3 min and a mixing tolerance scores of >3 are considered as having an acceptable end-use quality (Baenziger et al., 2001b), although year-to-year variation as seen in the check cultivar values can lead to selecting lines with lower mixing times and tolerance scores.
On the basis of high agronomic performance and acceptable end-use quality, 280 hard red winter wheat lines were planted in an unreplicated trial with replicated checks (Alliance, Millennium, ‘Pronghorn’ [PI 593047; Baenziger et al., 1997], ‘Wesley’ [PI 605742; Peterson et al., 2001], and 2137 planted every 100 plots at 20-plot intervals) and 30 hard white winter wheat lines (including ‘Nuplains’ [PI 612576] and ‘Trego’ [PI 612576; Martin et al., 2001] as checks) for a total of 330 plots. The hard red wheat lines were sorted on the basis of flowering date, with those having the earliest flowering dates being first in the nursery. This trial was planted in September 2000 at six locations (Lincoln, Mead, Clay Center, Grant, Sidney, and Alliance, NE). Each line was planted in a four-row plot with each row being 2.4 m long with 30 cm between rows, and all four rows were harvested using a small plot combine, with the exception of North Platte, which was abandoned due to hail. Over the winter, all of the lines were evaluated in the greenhouse for their resistance to stem rust using race TPMK. The lines were also evaluated at the USDA–ARS Cereal Disease Laboratory, St. Paul, MN, for stem rust resistance. The name Camelot (NE01604) was derived from this nursery as the line was harvested in 2001 (e.g., the 01) and it was entry 604 (the entries ranged from 401 to 730).
On the basis of grain yield, grain volume weight, plant height, flowering date, stem rust resistance, mixograph mixing time and tolerance, and agronomic appearance, Camelot and 56 other lines (19% selection intensity) were selected and planted in advanced yield trials with three check cultivars (Alliance, Pronghorn, and Wesley) in September 2001. These trials were planted in three replications at five locations (Lincoln, Mead, Clay Center, Sidney, and Alliance) and two replications at three locations (McCook, North Platte, and Grant) with the same plot size as the preliminary yield trials. The lines were evaluated for stem rust resistance in the University of Nebraska greenhouses and at the USDA–ARS Cereal Disease Laboratory, and remnant grain samples from western Nebraska (e.g., those harvested locations other than Lincoln or Mead, which were harvested for seed) were composited and analyzed for milling and bread-baking properties using 100-g pup loaves where the bake sample mix time, water absorption, baked loaf volume, and external and internal grain and texture were measured (using AACC approved methods; American Association of Cereal Chemists, 2000; Baenziger et al., 2001b). The lines were also evaluated for their resistance to Hessian fly (Mayetiola destructor Say) by the USDA–ARS Plant Science and Entomology Research Unit and Kansas State University.
On the basis of grain yield and other characteristics as described above, Camelot and 17 other lines (30% selection intensity) were selected and planted in the Nebraska Intrastate Nursery (NIN) in September 2002 using plot methods similar to previous trials. The NIN is the elite rainfed (nonirrigated) trial for the breeding program and was planted with three replications at Mead, Clay Center, North Platte, Sidney, and Alliance and with four replications at Lincoln. Lines continue in this nursery until they are released or dropped from further consideration. The lines were evaluated for winter survival, agronomic performance, stem rust resistance, Hessian fly resistance, and bread-making properties as previously described. The trial at Alliance was abandoned, but all other sites were harvested.
In September 2003, Camelot and nine lines (55% selection) continued testing in the NIN as described previously. All locations were harvested. In September 2004, Camelot and seven lines continued to be tested in the NIN (all locations were harvested and evaluated as described previously). Camelot was also entered into the cooperative USDA–ARS Hard Winter Wheat Northern Regional Performance Nursery (NRPN). In September 2005 Camelot continued testing in the NIN and NRPN and was entered into the Nebraska State Variety Trial (NESVT), the official rainfed and irrigated state variety trial for Nebraska. The number of replications in the NESVT varied from as low as three to as many as five harvested replications. The plot size (2.4 m by 1.2 m to three times that size) and row spacing (17.5 to 35 cm between rows) varied with the region of the state. The NESVT is planted at 13 to 15 rainfed and two to three irrigated locations in Nebraska or combined with close locations in Wyoming. Normally, one to three locations are lost yearly due to hail, freezes, drought, or severe disease. Camelot continued to be evaluated in the NIN and NESVT in 2006 and 2007 as described above.
Seed Purification and Increase
Seed purification of Camelot began in the 2004 crop year using visual identification and manual removal of variants (primarily tall and red-chaffed off-types) from bulk seed increases grown under rainfed conditions at Lincoln, NE. Seed harvested from the advanced yield trials at Lincoln, NE, in 2003 was planted in a short, unreplicated strip plot (1.2 m wide, 15 m long) in fall 2003. During grain filling and again at harvest, strips were rogued to remove tall, red-chaffed, and other variants. A subsample of seed harvested from these strips was planted in a longer strip plot (1.2 m wide, 45 m long) in fall 2004. This strip was rogued as in 2004. In fall 2005, a subsample of seed from this strip was planted at Mead, NE, in a Breeder seed (F3:11) increase block (approximately 0.2 ha) and rogued as in previous years. In 2007, Foundation seed was produced by planting all of the Breeder seed harvested in 2006, in a 5-ha rainfed seed increase block at Mead, NE. The Foundation seed increase block (F3:12) was rogued as in previous years. Camelot has been uniform and stable since 2005. Less than 0.5% of the plants were rogued from the Breeder seed increase in 2005. The rogued variant plants were taller in height (5–15 cm) or were awnless and/or with red chaff. Up to 1% (10:1000) variant plants may be encountered in subsequent generations. The Nebraska Crop Improvement Association and Mr. Roger Hammons provided technical assistance in describing the cultivar characteristics and accomplishing technology transfer.
Statistical Analyses
To analyze data during the development of Camelot, replicated trials with two replications were analyzed as randomized complete blocks and replicated trials with three or more replications were analyzed using the nearest neighbor (NNA) procedure of Agrobase 21 (Agronomix Software, Inc., Winnipeg, Canada; Stroup et al., 1994). Because Nebraska has three major wheat-producing regions (Peterson, 1992), the data were analyzed within a location within region and rarely over locations for the advanced and NIN trials. Location means and ranks were studied and lines were selected by having excellent performance within a location, across locations within a region, and all locations within a year based on the arithmetic mean of the NNA adjusted means, or across locations and years based on the arithmetic mean of the NNA adjusted means. A truncated selection procedure was used as a risk avoidance strategy (basically if a line did well in one or 2 yr and then poorly in the next year, the line was not continued because it might perform poorly in a producer's field). Analyses of the NRPN data used SAS (SAS Institute Inc., Cary, NC) for a randomized complete block design within locations and across locations within a year. Entries changed greatly between years in the NRPN, making over-year comparisons difficult. For the NESVT, the trials were analyzed using SAS using a row and column correction (PROC MIXED) for each location and analyzed across years within a region. Entries varied greatly across regions; hence, analysis across regions and locations was not done using SAS, but the arithmetic mean for lines in common were considered. Only entries common to the trials across years within a region in the NESVT (2004–2006) were analyzed using randomized complete block designs.
Characteristics
Agronomic and Botanical Description
While considerable data is available from the breeding nurseries during the line development, the majority of data presented here will be from the NESVT (Tables 1
, 2
, and 3
) and NRPN as their complete reports are readily available (http://varietytest.unl.edu/winterwheat.html, verified 17 June 2009; http://www.ars.usda.gov/Research/docs.htm?docid=11932, verified 17 June 2009. The mature plant height of Camelot (87 cm) is 1.3 cm shorter than widely grown semidwarf cultivar Millennium (PI 613099; Baenziger et al., 2001a) and 9.5 cm taller than Wesley (Table 1). Camelot has moderate straw strength (14% lodged), similar to Agripro Jagalene (Plant Variety Protection Office Certificate 200200160, 12%), but less than Wesley (7%), and Millennium (7%). The winter hardiness of Camelot (80%) is good to very good, slightly less than Nuplains, a nursery check cultivar, (86%), similar to ‘Nudakota’ (Plant Variety Protection Office Certificate 200600235, 79%), and comparable to other winter wheat cultivars adapted and commonly grown in Nebraska (data not shown but can be found at http://www.ars.usda.gov/Research/docs.htm?docid=11932, verified 17 June 2009). In irrigated environments, Camelot (6.8%) had higher scores than Jagalene (0.8%), Wesley (0.1%), and Millennium (4.7%) for lodging (Table 2). Other measurements of performance from comparison trials show that Camelot is moderately late in maturity (143 d after 1 January, data from 6 observations in eastern Nebraska), about 1 d later flowering than Alliance, similar to Wesley, and 1 d earlier than NE01643 and Millennium. Using data from the NRPN averaged over 2005 and 2006, Camelot is 6 d earlier than Nuplains and 7 d earlier than ‘Harding’ (a nursery check cultivar, PI 608049, Haley et al., 2000) for heading. The winter hardiness of Camelot (80%) is good to very good, similar to, but less than Nuplains (86%), and comparable to other winter wheat cultivars adapted and commonly grown in Nebraska.
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Disease and Insect Resistance
Camelot is moderately resistant to stem rust in field nursery tests inoculated with a composite of stem rust races (RCRS, QFCS, QTHJ, RKQQ, and TPMK) and superior to NE01643 (http://www.ars.usda.gov/SP2UserFiles/ad_hoc/54402000HardWinterWheatRegionalNurseryProgram/05nrpn.xls, verified 17 June 2009). In greenhouse tests, it is moderately resistant to races QFCS, MCCF, RKQQ, TPMK, and TTKS but susceptible to race TTTT (postulated genes are Sr6 and Srtmp). It is moderately resistant to leaf rust (caused by P. triticina Eriks), stripe rust (caused by P. striiformis Westendorp f. sp. tritici; data obtained from field observations in the Great Plains), and Hessian fly. On the basis of seedling infection to different races of P. triticina, Camelot was postulated to have leaf rust resistance gene Lr41. Camelot also is slightly more tolerant to Fusarium head blight (caused by Fusarium spp.; data obtained from misted screening nurseries in Nebraska and South Dakota) than many widely grown lines. It is moderately susceptible to wheat soilborne mosaic virus, and susceptible to barley yellow dwarf virus and wheat streak mosaic virus (data obtained from the NRPN, 2005–2006 and field observations in Nebraska).
Field Performance
Camelot was evaluated in Nebraska replicated yield nurseries starting in 2002, in the NRPN in 2005 and 2006, and in NESVT in 2005 to 2007. In the NESVT, it is widely adapted and consistently among the top grain-yielding cultivars throughout the state (Table 1) with better performance in western Nebraska. In irrigated (Table 2) and organic (Table 3) trials, it performs well, although it tends to lodge more than popular irrigated cultivars such as Wesley and Agripro Jagalene. The average Nebraska rainfed yield of Camelot of 3855 kg ha–1 (36 environments from 2005 to 2007) was greater than or similar to the yields of other popular cultivars such as ‘Antelope’ (PI 633910; Graybosch et al., 2005; 3467 kg ha–1), ‘Infinity CL’ (PI 639922; Baenziger et al., 2006; 3869 kg ha–1), Agripro Brand Jagalene (3541 kg ha–1), Millennium (3843 kg ha–1), ‘Wahoo’ (PI 619098; Baenziger et al., 2002; 3669 kg ha–1), and Wesley (3628 kg ha–1). The highest-yielding cultivar in those years was ‘NE01643’ (PI 647959; Baenziger et al., 2008), which is sold under the name Husker Genetics Brand ‘Overland’ (4119 kg ha–1). Although we have only 2 yr (seven environments) of data, Camelot performed well in irrigated environments where its grain yield (6133 kg ha–1) is similar to the popular cultivars Wesley (6234 kg ha–1) and Agripro Jagalene (6187 kg ha–1). Camelot (3968 kg ha–1) has also performed well in organic production systems (two environments), similar to Wahoo (3968 kg ha–1) and slightly superior to Millennium (3833 kg ha–1) and Wesley (3800 kg ha–1). Camelot is broadly adapted to the Northern Great Plains, as was evident by its performance in the NRPN, where it ranked 12th in 2005 (out of 32 lines tested) and 2006 (out of 30 lines tested) and consistently above the nursery mean (3858 kg ha–1). Compared with the check cultivars in the NRPN, Camelot (4222 kg ha–1) was higher yielding than Harding (3507 kg ha–1) and Nuplains (3719 kg ha–1).
In positioning Camelot, on the basis of performance data to date, it should be well adapted to most rainfed wheat production systems in Nebraska and in adjacent areas of the northern Great Plains. Being a broadly adapted wheat line may explain its good agronomic performance in the NRPN. Where it is adapted, Camelot should be a replacement for 2137, Wahoo, and Wesley (for rainfed production), although Wesley has better straw strength. Camelot is genetically complementary (meaning the compared lines do not have recent parents in common and there is less likelihood to have genes identical by descent) to Husker Genetic Brand Overland, Millennium, Infinity CL, and Antelope. It is noncomplementary (meaning they share common recent parents and may have a higher likelihood of having genes identical by descent) to Hatcher and 2137. To avoid genetic vulnerability caused by biotic and abiotic stresses, growers in Nebraska who grow more than one wheat cultivar are recommended to grow complementary cultivars.
End-Use Quality
The milling and baking properties of Camelot were determined for 5 yr by the Nebraska Wheat Quality Laboratory (Table 4
). In these tests, Millennium, an excellent milling and baking wheat, was used for comparison. All reported values were measured at a 140 g H2O 1000 g–1 flour basis. The average wheat and flour protein concentration of Camelot (135 and 127 g kg–1) were similar to Millennium (138 and 125 g kg–1) for the corresponding years. The similar grain protein content was confirmed by the Nebraska cultivar performance trials where Camelot had 122 g protein kg–1 compared with Millennium with a value of 120 g kg–1. The average flour extraction on the Buhler Laboratory Mill for Camelot (712 g kg–1) was slightly lower than Millennium (721 g kg–1). The flour ash content (44 g kg–1) was higher than Millennium (43 g kg–1). Dough mixing properties of Camelot were acceptable (mixtime peak was 3.6 min, and mixtime tolerance was scored as 3.5), which was weaker than Millennium (mixtime peak of 3.8 min, and mixtime tolerance scored as 3.5). Average baking absorption (618 H2O g kg–1) was slightly higher than Millennium (612 g H2O kg–1) for the corresponding years. The average loaf volume of Camelot (879 cm3) was lower than Millennium (890 cm3). The scores for the external loaf score, internal crumb grain, and texture ranged from 3.6 to 4.5, where 5 is excellent, which was better than Millennium, which ranged from 3.9 to 4.1. The overall end-use quality characteristics for Camelot (scored as 4.3, where 5 is excellent) was better than Millennium (4.0) and superior to many commonly grown wheat cultivars. Camelot should be acceptable to the milling and baking industries.
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The Nebraska Foundation Seed Division, Department of Agronomy and Horticulture, University of Nebraska–Lincoln, Lincoln, NE 68583 had Foundation seed available to qualified certified seed enterprises who are members of the NuPride Genetics Network in 2008. The U.S. Department of Agriculture will not have seed for distribution. The seed classes will be Breeder, Foundation, Registered, and Certified. The Registered seed class will be a nonsalable seed class. Camelot will be submitted for plant variety protection under P.L. 10577 with the certification option. A research and development fee will be assessed on all certified seed sales. Small quantities of seed for research purposes may be obtained from the corresponding author for at least 5 yr from the date of this release according to the provisions of the Wheat Worker's Code of Ethics (National Wheat Improvement Committee, 1995). A seed sample has been deposited in USDA–ARS National Center for Genetic Resources Preservation and in the USDA–ARS National Small Grains Collection, Aberdeen ID, and seed is freely available to interested researchers.
Acknowledgments
Camelot was developed with partial financial support from the Nebraska Agricultural Experiment Station and the Nebraska Wheat Development, Utilization, and Marketing Board. Partial funding for P.S. Baenziger is from Hatch project NEB-22-328, USDA, IFAFS competitive grant 2001-04462, USDA, NRICGP 00-353000-9266, 2004-35300-1470, and 2007-51300-0375, USDA, CSREES NRICAP grant number 2006-55606-16629, and USDA under Agreement No. 59-0790-4-092 which is a cooperative project with the U.S. Wheat & Barley Scab Initiative. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the authors and do not necessarily reflect the view of the USDA. Cooperative investigations of the Nebraska Agric. Res. Div., Univ. of Nebraska, and USDA–ARS.
Footnotes
All rights reserved. No part of this periodical may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. Permission for printing and for reprinting the material contained herein has been obtained by the publisher.
Received for publication May 15, 2009.
References
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| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
