AAC Icefield

Wheat

Variety Description

Varieties used for comparison: 'Flourish', 'AAC Gateway' and 'Whitebear'

Summary: At booting, the frequency of plants with recurved flag leaves is medium for 'AAC Icefield' whereas the frequency is absent or very low for 'Flourish', absent or very low to low for 'AAC Gateway' and high to very high for 'Whitebear'. The anthocyanin colouration of the flag leaf auricle is weak to strong for 'AAC Icefield' whereas it is absent or very weak for 'AAC Gateway' and 'Whitebear'. The flag leaf of 'AAC Icefield' is wider than that of 'Flourish' and 'AAC Gateway'. The plants of 'AAC Icefield' head later than those of 'Whitebear'. At maturity, the spike for 'AAC Icefield' is longer than the spike of 'Flourish' and 'AAC Gateway'. The lower glume shoulder shape is sloping to slightly sloping for 'AAC Icefield' whereas it is elevated to strongly elevated for 'AAC Gateway'. The kernel is white for 'AAC Icefield' whereas it is medium red for 'Flourish' and 'AAC Gateway'. The kernel size is medium for 'AAC Icefield' whereas it is large for 'Whitebear'.

Description:

PLANT: winter type, hard white, common wheat, semi-erect to intermediate growth habit at the 5 to 9 tiller stage, medium frequency of plants with recurved flag leaves, matures mid-season

SEEDLING (4-leaf stage): absent or very weak intensity of anthocyanin colouration of the coleoptile, glabrous sheath and blade of the lower leaves

FLAG LEAF: weak to strong intensity of anthocyanin colouration of the auricles, medium glaucosity of sheath, glabrous blade and sheath

CULM: strong glaucosity, slightly curved neck
STRAW: very thin pith in cross-section, no anthocyanin colouration at maturity

SPIKE: medium glaucosity, tapering, medium density, white to yellow at maturity, inclined to nodding attitude
AWNS: shorter than length of spike, white to light yellow at maturity
LOWER GLUME SHOULDER: absent or very narrow to narrow, sloping to slightly sloping
LOWER GLUME: medium to long, narrow to medium width, glabrous
LOWER GLUME BEAK: short to medium length, slightly curved shape

KERNEL: white, medium sized

AGRONOMIC CHARACTERISTICS: good resistance to lodging, fair winter hardiness

DISEASE REACTIONS: resistant to Stem rust (Puccinia graminis f. sp. tritici); moderately resistant to Leaf rust (Puccinia recondita) and Stripe rust (Puccinia striiformis); moderately resistant to moderately susceptible to Fusarium head blight (Fusarium species and specifically Fusarium graminearum); and susceptible to Common bunt (Tilletia caries, Tilletia foetida)

Origin & Breeding History: 'AAC Icefield' (experimental designations LF1706W and W530) was selected from the cross 'McClintock'/'W349' conducted in 2000 at the Agriculture and Agri-Food Canada Lethbridge Research and Development Centre, Lethbridge, Alberta. In 2001-2002, 279 F1 derived, double haploid lines were produced. In 2003, 219 lines were evaluated with selection based on winter survival, plant type, plant vigor, plant height, straw strength, seed colour, test weight, protein contentration and SDS sedimentation volume. The resulting 19 selections were planted in a stem and leaf rust nursery at the University of Manitoba in Winnipeg, Manitoba and the line LF1706W was identified for evaluation in a single replicate preliminary trial in Lethbridge in 2005. Further agronomic, disease resistance and end-use quality evaluations took place in replicated, multi-location trials and supplementary nurseries in 2006 and 2009. LF1706W was tested as W530 in the Western Winter Wheat Cooperative Registration Trials from 2012/13 to 2016/17.

Tests & Trials: The comparative trials were conducted during the 2016 and 2018 growing seasons at the Agriculture and Agri-Food Canada Lethbridge Research and Development Centre, Lethbridge, Alberta. Plots consisted of 4 rows, with a row length of 3.5 metres and a row spacing of 23 cm. There were 4 replications arranged in an RCB design. Measured characteristics were based on a minimum of 20 measurements per variety per year. Mean differences are significant at the 5% probability level based on a Student's t-test. Disease reaction ratings were provided from the Western Canada Winter Wheat Cooperative Registration trials conducted from 2013 to 2017.

Comparison tables for 'AAC Icefield' with reference varieties 'Flourish', 'AAC Gateway' and 'Whitebear'

Flag leaf width (cm)

Days to heading (days from planting to when 50% heads are fully emerged from boot)

Spike length (excluding awns) (cm)

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Wheat: 'AAC Icefield' (centre left) with reference varieties 'Flourish' (left), 'Whitebear' (centre right) and 'AAC Gateway' (right)

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Wheat: 'AAC Icefield' (top left) with reference varieties 'Whitebear' (top right), 'AAC Gateway' (bottom left) and Flourish' (bottom right)