MONTANA

Montana State University

Department of Plant, Soil & Environmental Sciences, Bozeman, MT 59717, USA.

L.E. Talbert, P.L. Bruckner, S.P. Lanning, J.E. Berg, W.L. Morrill (Entomology Research Laboratory), R. Qu, and K.A. Tilley.

1994 wheat crop.

Although the growing season ended up very dry, Montana's wheat crop was near average in 1994. The year began with good moisture supplies, which resulted from reserves of the very wet 1993 season. In most areas, precipitation ended after mid-June, and yields declined as stress intensified till harvest. Winter wheat production was down 37 % from 1993, primarily because of wet conditions at planting that resulted in a 700,000 acre decline in planted acreage. Spring wheat acreage increased 650,000 acres from 1993, and the 1994 Montana spring wheat crop was the largest ever, over 100 million bushels. In 1994, Montana producers harvested 1.85 and 3.35 million acres of winter and spring wheat, respectively. Winter wheat averaged 35 bu/acre and spring wheat 30 bu/acre. Primary cultivars in Montana are Neeley, Tiber, Rocky, Redwin, and Judith winter wheat and Amidon, Rambo, Grandin, Fortuna, Lew, and Newana spring wheat.

Breeding objectives.

Objectives of both the HRW and HRS wheat programs include sawfly resistance, Russian wheat aphid resistance, wheat streak mosaic virus resistance, end-use qualities, and development of hard white wheats adapted to Montana. In addition, the winter wheat program has initiated an anther culture program and a selection program for enhanced cold tolerance under controlled conditions.

Wheat streak mosaic virus. In 1994, interdisciplinary research was initiated to develop methods for prevention and control of the wheat curl mite (WCM) and WSMV through support of the Montana Wheat and Barley Research and

Marketing Committee. Objectives of this research include: 1) varietal evaluation of WSMV tolerance; 2) identification of oversummering reservoirs important to WSM epidemiology, cultivar resistance to WCM, and efficacy of soil-applied insecticides; 3) identification of molecular markers for WSMV and WCM resistance and transfer of these genes into adapted Montana wheats; and 4) development of resistant wheat lines by transformation with viral coat protein and replicase genes.

Wheat stem sawfly. Wheat stem sawfly continues to be the most destructive insect pest of wheat in Montana. It adapted from wild grasses to spring wheat in the early 1900s and, by 1980, infested winter wheat as well. Currently, in some fields, all stems large enough to produce heads are infested. Sawfly infestation results in reduced head weight, lower grain quality, and lodging prior to harvest. Solid-stemmed wheats are infested as well, although they are less prone to yield reduction from sawfly feeding and more resistant to lodging from stem cutting at wheat maturity. Two species of parasitoids are prevalent in wheat. Parasitoid activity is enhanced by long, cool growing seasons, as occurred in 1993 and 1994. The level of parasitism near Conrad, MT, is currently about 99 %. Effects of this level of parasitism on field populations of sawfly will be determined in 1995. Insecticides are being tested on field borders to kill wasps that are dispersing from infested stubble to standing crops. A key factor for successful control using insecticides is timing. Several types of emergence cages are being tested to assist in determining wasp emergence.

Cultivar release.

`Vanguard' (Lew/Tiber//Redwin) hard red winter wheat with stem solidness and resistance to feeding and cutting damage of wheat stem sawfly was approved for release in 1995. Vanguard has winter hardiness similar to that of Rocky and yield potential similar to that of Redwin in the absence of sawfly. Vanguard is the first sawfly-resistant winter wheat cultivar released in Montana since 'Rego' in 1957 and 'Sawmont' in 1965. Vanguard is targeted for sawfly-infested areas of the southern golden triangle where high levels of winter hardiness are not required.

Personnel.

Dr. Kathy A. Tilley was hired as cereal chemist and director of the Cereal Quality Laboratory in 1994. Jim E. Berg was hired as a research associate with the winter wheat breeding program in August, 1994.

Publications.

Chen HB, Martin JM, Lavin M, and Talbert LE. 1994. Genetic diversity in hard red spring wheat based on sequence-tagged-site PCR. Crop Sci 34:1628-1632.

Morrill WL, Kushnak GD, Bruckner PL, and Gabor JW. 1994. Wheat stem sawfly (Hymenoptera: Cephidae) damage, rates of parasitism, and overwinter survival in resistant wheat lines. J Econ Ent 87:1372-1376.

Riesselman J, Bruckner PL, Carlson G, and Brastrup R. 1994. Effect of WSMV on yield in commercially grown hard red winter wheat relative to comparable long term averages, 1993. Biol and Cult Tests for Control of Plant Dis 9:129.

Talbert LE, Blake NK, Chee PW, Blake TK, and Magyar GM. 1994. Evaluation of sequence-tagged-site PCR markers as molecular markers in wheat. Theor Appl Genet 87:789-794.

NEBRASKA

University of Nebraska and the USDA-ARS

Lincoln, NE 68583, USA.

Growing conditions and production.

P.S. Baenziger, C.J. Peterson (USDA-ARS), R.A. Graybosch (USDA-ARS), D.R. Shelton, L.A. Nelson, D.D. Baltensperger, D.J. Lyons, and G.L. Hein, University of Nebraska and USDA-ARS.

As opposed to previous years, the 1994 state wheat crop, though variable, had a more "normal" season. The estimated production was 71.4 million bushels from 2.1 million harvested acres with a state average yield of 34.0 bu/acre. This is a slightly lower average yield than last year (35 bu/acre) and would have to be considered less than should be expected in an average production year. Winterkilling was minimal throughout the state. As compared to the previous 2 years, this growing season would have to be considered as being cooler in the fall and early spring, followed by warmer than normal temperatures with less moisture. The general effect was the season was earlier, drier, and warmer. Wind damage was significant in western Nebraska and a long drought and heat were the main limitations to wheat production. Insects (Russian wheat aphid and Hessian fly) and diseases (viruses and rusts) were minor.

New cultivars. Two new wheat varieties, Nekota and Niobrara, were released in 1994.

Nekota (P.I. 584997, also known as NE88427) was developed cooperatively by the South Dakota Agricultural Experiment Station, Nebraska Agricultural Experiment Station, and the Northern Plains Area, Agricultural Research Service, U. S. Department of Agriculture. The name was chosen in recognition of Nekota's adaptation to both South Dakota and Nebraska. Nekota is an increase of a hard red winter wheat F₃-derived line from the cross `Bennett/TAM107', which was made in 1982. Nekota was identified in 1988 and tested as NE88427 in Nebraska yield trials starting in 1989 and the Southern Regional Performance Nursery in 1991 and 1992. The current breeder seed originated from a purification program in 1991-1992, 1992-1993, and 1993-1994 designed to remove off-types by roguing.

Nekota in Nebraska is a white chaffed, awned, winter hardy, moderately early, semidwarf wheat (similar in anthesis date to Alliance, later than TAM107, earlier than Arapahoe) that is 6 cm taller than Vista and 2 cm shorter than Alliance in plant height. Nekota (79 mm) has an intermediately long coleoptile (longer than Alliance (66 mm), similar to TAM107 (80 mm)). It is moderately susceptible to leaf rust and is susceptible to soilborne and wheat streak mosaic viruses and Hessian fly. Nekota is heterogeneous for secalins encoded by the Sec-1 locus, which is indicative of the Amigo translocation (1A-1R) derived from TAM107. Plants containing the Amigo translocation have been reported as being a nonpreferred host for wheat curl mite, the vector of wheat streak mosaic virus. Hence, in the field, it may have less wheat streak mosaic virus than varieties that do not contain this nonpreference trait. It is moderately resistant to stem rust (contains genes Sr6 and is heterogeneous for the Amigo gene). Nekota (75.6 kg/hl) has good test weight characteristics (superior to those of Siouxland (74.5 kg/hl), Redland (73.4 kg/hl), Arapahoe (73.8 kg/hl), Vista (73.6 kg/hl), and Alliance (73.8 kg/hl)) and winter hardiness. The straw strength of Nekota is adequate (superior to that of Arapahoe, but less than that of Redland).

In 3 years of testing in the Nebraska Fall Sown Cereal Variety Trials (37 environments), Nekota (3,610 kg/ha) was lower yielding than Alliance (3,680 kg/ha), but superior to Redland (3,510 kg/ha), Rawhide (3,350 kg/ha), and Siouxland (3,270 kg/ha). In the 2 years (1991 and 1992) that it was tested in the Southern Regional Performance Nursery, Nekota (3,640 kg/ha) averaged 8% lower grain yield than TAM107, a broadly adapted cultivar. However, in the northern high plains region of the testing site, Nekota (3,080 kg/ha) had a slightly higher yield than TAM107 (3,040

kg/ha). The recommended growing region for Nekota needs further refinement, but would include southeast, southcentral, and southwest Nebraska in the absence of leaf rust or if fungicide applications were used to control this disease. It also has done well in South Dakota. Nekota would be considered genetically similar to TAM 107, Bennett, and Niobrara.

Nekota's performance in the South Dakota Crops Performance Testing Variety Trial (1993, 1994; 22 environments) has been similar to its performance in Nebraska. Nekota is an early (3 days later than TAM107 and 1 day earlier Alliance) semidwarf (2.5 cm taller than TAM107 and Vista and 2.5 cm shorter than Alliance) wheat. Nekota had exceptional test weight characteristics (78.4 kg/hl) and was to superior Abilene (77.9 kg/hl), Arapahoe (76.5 kg/hl), Vista (76.2 kg/hl), and Alliance (76.0 kg/hl). The yield of Nekota (3,400 kg/ha) was slightly less than that of Alliance (3,460 kg/ha), but was superior to those of Arapahoe (3,340 kg/ha), Seward (3,300 kg/ha), Vista (3,290 kg/ha), and TAM107 (3,140 kg/ha).

The milling and baking properties of Nekota were determined using 6 years of testing by the Nebraska Wheat Quality Laboratory with Arapahoe and Scout 66 as check cultivars. The average wheat and flour protein contents of Nekota are lower than those of Arapahoe, but higher than those of Scout 66. The flour yield is less than that of Scout 66, but higher than that of Arapahoe. The dough mixing properties were weaker than those of Arapahoe and similar to those of Scout 66. Although the baking absorption of Nekota was similar to that of Arapahoe and less than that of Scout 66, average loaf volumes were greater than those of Scout 66 and less than those of Arapahoe. The external appearance and internal attributes of the baked bread loaf indicated generally acceptable quality characteristics.

The South Dakota Foundation Seed Division, Department of Plant Science, South Dakota State University, and the Nebraska Foundation Seed Division, Department of Agronomy, University of Nebraska-Lincoln will have foundation seed available to qualified certified seed producers in 1994. The seed classes will be breeder, foundation, registered (salable only among crop improvement members), and certified.

Niobrara (P.I. 584996, also known as NE89522) was developed cooperatively by the Nebraska Agricultural Experiment Station and the Northern Plains Area, Agricultural Research Service, U. S. Department of Agriculture. Niobrara is an increase of a hard red winter wheat F₃-derived line from the cross `TAM 105*4/Amigo//Brule sel', which was made in 1983. Niobrara was identified in 1989 and tested as NE89522

in Nebraska yield trials starting in 1990, and the Northern Regional Performance Nursery in 1993. The current breeder seed originated from a purification program in 1991-1992 and 1992-1993 designed to remove off-types by roguing.

Niobrara is a white chaffed, awned, winter hardy, moderately early, semidwarf (2 days later than Alliance and 2 days earlier than Redland) wheat that is 11 cm taller than Vista (74 cm), 5 cm taller than Alliance (80 cm) and similar in height to Redland (84 cm). It is susceptible to Hessian fly and soilborne mosaic virus and moderately susceptible to leaf rust. In greenhouse tests, it appears to be slightly less tolerant to wheat streak mosaic virus than Redland. It is heterogeneous for secalins, encoded by the Sec-1 locus, which is indicative of the Amigo translocation (1A-1R). Plants containing the Amigo translocation have been reported as being a nonpreferred host for wheat curl mite, the vector of wheat streak mosaic virus. Hence, in the field, the line may have both some tolerance to the virus and nonpreference to the virus vector. Niobrara is moderately resistant to stem rust (contains genes Sr6 and is heterogeneous for the Amigo gene). Using data from the 1993 and 1994 Nebraska Fall Sown Cereal Variety Trials (26 environments), Niobrara is a lower test weight wheat (73.4 kg/hl) similar to that of Alliance (73.3 kg/hl), slightly superior to that of Redland (73.1 kg/hl), but lower than Arapahoe (73.6 kg/hl), Siouxland (74.5 kg/hl), and Nekota (75.4 kg/hl). The straw strength is adequate (superior to Arapahoe, but less than Redland).

Niobrara has had an excellent yield performance record in Nebraska. It was the highest grain-yielding line in the Nebraska Fall Sown Cereal Variety Trials State Variety Trial in each year that it was tested (1993 and 1994). The average grain yield was 3,890 kg/ha which was superior to those of Alliance (3,830 kg/ha), Vista (3,700 kg/ha), Redland (3,690 kg/ha), and Siouxland (3,450 kg/ha). Niobrara also had the highest average yield of the 15 lines tested in both

1992 and 1993 in the Uniform Northern Regional Performance Nursery. In the 4 years (1991-1994) that Niobrara (3,180 kg/ha) has been tested in the Nebraska Intrastate Nursery, only Alliance (3,260 kg/ha) had a superior yield record. For comparison, the grain yields of Redland, Vista, Arapahoe, and TAM107 were 3,070; 3,040; 3,000; and 2,840 kg/ha, respectively. The primary growing region is southwest Nebraska, northern Nebraska, and the panhandle, where its winter hardiness, plant height, tolerance for cooler weather, and disease resistance are most effective. On the basis of parentage, Niobrara would be considered genetically similar to Brule, Redland, Arapahoe, Vista, and Nekota.

The milling and baking properties of Niobrara were determined using 5 years of testing by the Nebraska Wheat Quality Laboratory, with Arapahoe and Scout 66 as check cultivars. The average wheat and flour protein contents of Niobrara is lower than Arapahoe and Scout 66. The flour yield is less than that of Scout 66, but higher than that of Arapahoe. The dough mixing properties were similar to those of Arapahoe and stronger than those of Scout 66. Although the baking absorption of Niobrara was less than those of Arapahoe and Scout 66, average loaf volumes were greater than those of the two check cultivars. The external appearance and internal attributes of the baked bread loaf indicated generally acceptable quality characteristics.

The Nebraska Foundation Seed Division, Department of Agronomy, University of Nebraska-Lincoln will have foundation seed available to qualified certified seed producers in 1994. The seed classes will be breeder, foundation, registered (salable only among crop improvement members), and certified. Niobrara will be submitted for registration and plant variety protection under P.I. 910577 with the certification option.

Increase of new experimental lines. Three experimental wheats are in large-scale increase for possible release in 1995. They are NE88584 (Centura/Dawn//Colt sib), NE90479 (KS83H2510 (H11)/Brule 83 Composite), and NE90524 (Brule field sel. #5/5/Bez1/3/Ctk78//Arthur/Ctk78/4/Cody).

NE88584 is a tall, long coleoptile wheat with adequate straw strength. It has very good test weight characteristics and moderate sized kernels. It would be considered as a medium early wheat. It has good stem rust resistance (contains Sr6) and moderate resistance to leaf rust. It is susceptible to Hessian fly, wheat streak mosaic virus, wheat soilborne mosaic virus, and Russian wheat aphid. It has been tested for 2 years in the state variety trials, and the target area for best adaptation would be western Nebraska and Wyoming. In this area, its yield is similar to that of Buckskin, but NE88584 has better disease resistance. The overall milling and baking quality would be considered as above average.

NE90479 is a moderately tall, intermediate coleoptile length wheat (similar to TAM107) with average straw strength. It has large kernels and very good test weight characteristics. It would be considered a medium maturity wheat. It is moderately resistant to stem rust and wheat soilborne mosaic virus. It is moderately susceptible to leaf rust, Hessian fly, and wheat streak mosaic virus. It is susceptible to Russian wheat aphid. In its first year of testing in the state variety trial, it seems to do particularly well in eastern and southeastern Nebraska. This is the first wheat in many years with good wheat soilborne mosaic virus resistance, which will help its adaptation in its targeted area of southeastern and southcentral Nebraska. The overall milling and baking quality would be considered as well above average. This is a good quality wheat. Of the three mentioned here, NE90479 probably has the highest likelihood of release in 1995.

NE90524 is a moderately tall, long coleoptile wheat with average straw strength. It has average sized kernels and good test weight characteristics. It would be considered a medium maturity wheat. It is moderately resistant to stem rust (contains Sr6) and moderately susceptible to leaf rust. It is susceptible to wheat streak mosaic virus, wheat soilborne mosaic virus, Hessian fly, and Russian wheat aphid. In its first year of testing in the state variety trial, it seemed to have an average performance throughout the state. Hence, it will need an additional year of testing to determine its target area, should it be released. The overall milling and baking quality would be considered as average for Nebraska released varieties.

The following lines are under small-scale increase with earliest possible release in 1996: NE90625 (TX79a2729//Caldwell/Brule field sel # 6/3/Siouxland), NE91631 (NE82761/Brule 84 sel.), NE91648 (NE82671/2/Ctk78*2/Lov 13), and NE91651 (NE82671/2/Ctk78*2/Lov 13).