Objective: 

To evaluate spring wheat experimental lines for wheat midge resistance and agronomic performance in environments and cropping systems where the wheat midge is prevalent. 

Results:

Four experimental spring wheat lines were evaluated for resistance to the wheat midge in comparison to the midge resistant and susceptible check varieties, Egan and Hank, respectively. This nursery was established at Kalispell and Conrad, MT. Midge populations were low to non-existent at both locations with the susceptible variety, Hank, having an average of only 0.7 and 4.6 larvae per spike at Conrad and Kalispell, respectively. As a result, it was not possible to assess the level of resistance expressed in the experimental lines. However, the agronomic performance of the entries was determined.

At Kalispell, significant differences were observed for heading, height, stripe rust, yield, protein, test weight, and number of wheat midge per spike (Table 2). Heading averaged 178 days. Plant height averaged 33.1 inches and ranged from 30.2 inches for MT 1573 to 37.0 inches for Egan. Stripe rust was present in the nursery despite having been treated with a fungicide. Stripe rust infection averaged 13.4% and ranged from 4.3% for Egan to 35.0% for Hank. Tan spot also was present, and was significant at a probability level of 0.054 percent. Tan spot infection averaged 13.8% and ranged from 0.0% for Egan, to 31.7% for MT1573. Yield averaged 91.1 bu/A, and ranged from 82.8 bu/A for Hank to 101.6 bu/A for Egan. Protein averaged 14.15%, and ranged from 13.47% for MT 1570 to 15.59% for Egan. Test weight averaged 59.9 lb/bu and ranged from 58.1 lb/bu for Hank to 61.3 lb/bu for MT 1570. The number of wheat midge per spike averaged 0.8. The susceptible variety Hank had 4.6 wm/spike while the resistant varieties afforded complete mortality.

At Conrad, no significant differences were observed for height, lodging, yield, test weight, protein or the number of larvae per spike (Table 3). Yields averaged 65.9 bu/A , but test weights were low, averaging 55.3 lb/bu. Proteins averaged 14.49 and all entries exceed 14% except for MT 1574. Egan had the highest protein at 15.08 percent.

Summary:

The four experimental lines provided 100% midge control in Kalispell. However, in Conrad there was less than 1% infestation. Additionally, the experimental lines are significantly shorter than Egan in Kalispell but no differences were observed in Conrad. However, they produced lower yields than Egan. Efforts should continue to identify short stature, high yielding, and midge resistant wheat lines.

Table 1. Materials and Methods

Kalispell
Seeding Date: 5/2/2016 Harvest Date 8/26/2016
Julian Date: 123 Julian Date 239
Seeding Rate: 80 lb/A Soil Type Creston SiL
Previous Crop: Spring wheat Soil Test: 99-32-432-10
Tillage: Conventional Fertilizer: 235-40-60
Herbicide:  Huskie 11 oz/A + Axial 16.4 oz/A + NIS 1 qt/100 gal + UAN 28%
Fungicide Tilt at 4 oz.
Conrad
Seeding Date: 5/4/2016 Harvest Date: 9/15/2016
Julian Date: 125 Julian Date: 259
Seeding Rate N/A Soil Type: Silty Clay
Previous Crop: Spring wheat Soil Test: N/A
Tillage: No-till
Fertilizer: 100 lb. ammonium sulfate, 381 lb. urea, 60 lb. N
Herbicide:

Preplant: RT3 18 oz/A + Hellfire 1 qt/A

Postplant: 4 oz/ac Rimfire Max, 16 oz/ac Brox M, 4 oz/ac propiconazole

Table 2. Agronomic data from the evaluation of Sm1 advanced spring wheat lines, Kalispell, MT - 2016

Cultivar HD Julian HT in. SR% TS% LOD% YLD bu/A1 PRO%2 TWT lb/bu1 WM no/spk
Egan 179 37.0 4.3 0.0 0.0 101.6 15.59 58.6 0.0
Hank 178 32.4 35.0 3.3 0.0 82.8 13.48 58.1 4.6
MT 1570 178 31.9 14.0 11.7 2.3 94.8 13.47 61.3 0.0
MT 1572 178 32.6 10.0 19.3 0.0 89.5 14.64 60.8 0.0
MT 1573 178 30.2 7.3 31.7 0.0 93.9 13.72 60.9 0.0
MT 1574 179 34.5 10.0 16.7 0.0 83.8 14.02 59.5 0.0
Mean 178 33.1 13.4 13.8 0.4 91.1 14.15 59.9 0.8
CV 0.2 2.0 38.1 80.5 424.3 3.8 1.16 0.3 80.2
LSD 0.7 1.2 9.3 20.2 ns 6.2 0.30 0.4 1.1
PR>F 0.0042 0.0001 0.0003 0.0538 0.4651 0.0004 0.0001 0.0001 0.0001

HD: heading date; HT: height; SR: stripe rust; TS: tan spot; LOD: lodging; YLD: yield; PRO: protein; TWT: test weight; WM: wheat midge; no/spk: number/spike; ns: non-significant

1adjusted to 13% moisture; 2adjusted to 12% moisture

Table 3. Agronomic data from the evaluation of Sm1 spring wheat lines, Conrad, MT - 2016

Cultivar HT in. LOD % YLD bu/A1 PRO %2 TWT lb/bu1 WM no/spk
Egan 32.3 3.7 73.8 15.08 56.6 0.0
Hank 31.7 0.5 56.2 14.10 53.4 0.7
MT 1570 30.3 0.5 64.4 14.61 54.2 0.3
MT 1572 32.3 0.5 69.5 14.95 55.6 0.3
MT 1573 28.3 0.5 61.4 14.43 56.6 0.0
MT 1574 31.0 6.8 70.1 13.77 55.2 0.3
Mean 31.0 2.1 65.9 14.49 55.3 0.3
CV 6.1 144.2 13.8 6.07 2.7 182.0
LSD ns ns ns ns ns ns
Pr>F 0.1704 0.1191 0.2673 0.4846 0.1247 0.6113

HD: heading date; LOD: lodging; YLD: yield; PRO: protein; TWT: test weight; WM: wheat midge; no/spk: number/spike; ns: non-significant

1adjusted to 13% moisture; 2adjusted to 12% moisture