View Full Table | Close Full ViewTable 1.

Description of test sites at Coalhurst and Nobleford, AB, Canada, and summary of agronomic practices performed during the study period 2006 to 2009.

 
Variable
Location Coalhurst, AB, Canada
Nobleford, AB, Canada
Latitude and longitude 49°44' N, 112°57 W
49°54'N, 112°58' W
Soil zone/series/texture Orthic Dark Brown Chernozemic Clay Loam (Typic Boroll)
Orthic Dark Brown Chernozemic Clay Loam (Typic Boroll)
Crop year 2006 2007 2008 2009 2006 2007 2008
Sowing date 6 May 25 Apr. 30 Apr. 4 May 17 May 17 Apr. 30 May
Harvest date 1 Sept. 5 Sept. 9 Sept. 11 Sept. 12 Sept. 28 Aug. 30 Sept.
Mean temperature and light intensity (Lm m−2) × 1000 °C Lux °C Lux °C Lux °C Lux °C Lux
June 19.3 26.8 21.9 26.4 20.5 28.4 22.1 49.7
July 25.2 29.3 20.8 27.2 20.8 30.6 26.2 28.8 20.9 42.7
August 21.3 28.4 20.8 20.4 19.4 25.0 20.7 24.8 20.9 37.1
Precipitation, mm
1 May to 15 Sept. long-term avg. = 251 150 164 380 241 150 164 380
Annual long-term avg. = 398 331 342 525 417 331 342 525



View Full Table | Close Full ViewTable 2.

Insect data summary of LSmeans for main effects variety and seeding rate, collected from sites near Nobleford and Coalhurst, AB, Canada 2006 to 2009.

 
Factor Treatment WSS† infestation Parasitism of WSS Pith rating (1 = hollow; 5 = solid) Stem diameter
% mm
Variety (main plot) AC Avonlea 30 8 2.4 2.62
Lillian 43 16 3.0 2.46
1:1 Blend of Lillian:Go 51 22 2.1 2.52
CDC Go 52 28 1.4 2.65
SED‡ 5.02 4.58 0.182 0.043
Pr > F 0.002 0.003 <0.0001 0.0011
LSD (0.05)§ 10 9 0.38 0.09
Seed rate (subplot) 150 seeds m−2 49 21 2.4 2.69
250 seeds m−2 44 18 2.2 2.57
350 seeds m−2 42 18 2.2 2.51
450 seeds m−2 41 18 2.2 2.49
SED 3.62 1.54 0.054 0.026
Pr > F 0.109 0.224 0.006 <0.0001
LSD (0.05) 0.12 0.05
Linear trend Linear equation (Y) −0.0288x+52.49 −0.006x+2.43 0.0007x+2.763
Regression value (R2) 0.91 0.60 0.90
Contrasts Linear 0.021 0.162 0.002 <0.0001
Pr > F Quadratic 0.449 0.138 0.046 0.026
Cubic 0.949 0.616 0.811 0.934
Variety × Seed rate Pr > F 0.003 0.261 0.391 0.353
WSS, wheat stem sawfly.
SED, Standard error of the difference.
§LSD, Fisher's protected least significant difference.



View Full Table | Close Full ViewTable 3.

Agronomic summary of mean responses for main effects of variety and seeding rate, collected from sites near Nobleford and Coalhurst, AB, Canada 2006 to 2009.

 
Factor Treatment Grain yield Stand establishment Spike density Seed mass Grain bulk density Grain protein Spikes per plant
Mg ha−1 plants m−2 heads m−2 g 1000−1 kg hL−1 %
Variety (main plot) AC Avonlea 3.15 163 281 39.9 76.7 12.2 2.1
Lillian 2.75 183 367 30.1 75.7 13.4 2.5
1:1 Blend of Lillian:Go 2.93 169 344 32.5 76.2 13.4 2.5
CDC Go 2.90 169 335 34.5 76.7 13.2 2.5
SED† 0.107 7.57 11.80 0.713 0.392 0.254 0.117
Pr > F 0.0138 0.109 <0.0001 <0.0001 0.044 0.0004 0.011
LSD (0.05)‡ 0.23 26 1.50 0.82 0.53 0.26
Seed rate (subplot) 150 seeds m−2 2.56 115 288 34.3 75.3 13.5 2.8
250 seeds−2 2.98 157 323 34.3 76.4 13.0 2.5
350 seeds m−2 3.02 196 354 33.9 76.6 12.9 2.2
450 seeds m−2 3.16 214 362 34.1 76.9 12.8 2.1
SED 0.118 10.87 10.69 0.226 0.176 0.121 0.097
Pr > F 0.0005 <0.0001 <0.0001 0.207 <0.0001 0.0002 <0.0001
LSD (0.05) 0.24 24 21 0.37 0.25 0.21
Linear trend Linear equation (Y) 0.0018x+2.378 0.337x+70.15 0.253x+255.85 0.0046x+74.97 −0.0022x+13.71 −0.0024x+3.12
Regression (R2) value 0.85 0.97 0.97 0.82 0.84 0.96
Contrasts Linear 0.0001 <0.0001 <0.0001 0.107 <0.0001 <0.0001 <0.0001
(Pr > F) Quadratic 0.099 0.133 0.068 0.651 0.003 0.058 0.277
Cubic 0.205 0.608 0.581 0.179 0.080 0.517 0.506
Var. × seed rate Pr > F 0.0003 0.399 0.082 0.011 0.310 0.496 0.183
SED, Standard error of the difference.
LSD, Fisher's protected least significant difference.



View Full Table | Close Full ViewTable 4.

Correlation matrix of insect-related variables, grain yield, yield components, and grain protein in spring wheat grown in areas prone to wheat stem sawfly (WSS) attack.

 
Pearson correlation coefficients
Variable Stem solidness Rate of parasitism on WSS Stems infested by WSS Grain yield Stand establishment Spike density Spikes per plant Grain protein
Stem diameter –† −0.53 0.27 0.49
Stem solidness 1 −0.42 −0.22
Rate of parasitism 1 0.77 0.23 −0.53 0.42
Stems infested by WSS 1 −0.42 −0.26 −0.26
Grain yield 1 −0.48 0.71 0.70 −0.23
Stand establishment 1 −0.22 −0.82 0.25
Spike density 1 0.56
Spikes per plant 1
Grain protein 1
‘-’ = P > 0.05; all other r values presented at P ≤ 0.05.