Denomination: 'Snowhite476'
Previously Proposed Denomination: 'HY476'
Botanical Name: Triticum aestivum
Applicant/Holder: Agriculture & Agri-Food Canada, Swift Current Research and Development Centre
1 Airport Road
P.O. Box 1030
Swift Current, Saskatchewan
S9H 3X2
Breeder: Ron De Pauw, Agriculture & Agri-Food Canada, Swift Current, Saskatchewan
Agent in Canada: FarmPure Seeds Inc.
426 McDonald Street
Regina, Saskatchewan
S4N 6E1
Tel: 306-791-0500 ext 223
Application Date: 2004-04-26
Application Number: 04-4179
Grant of Rights Date: 2007-08-13
Certificate Number: 2823
Date rights surrendered: 2008-08-14

Variety Description

Varieties used for comparison: 'AC Karma' and 'AC Vista'

Summary: 'Snowhite476' has medium anthocyanin on the coleoptile while 'AC Vista' has no anthocyanin. 'Snowhite476' has a shorter flag leaf than 'AC Vista' and a wider flag leaf than the reference varieties. 'Snowhite476' has stronger anthocyanin colouration on the auricle than 'AC Karma'. 'Snowhite476' has stronger glaucosity on the flag leaf sheath than 'AC Vista'. 'Snowhite476' heads later and has a taller plant height than 'AC Vista'. 'Snowhite476' has stronger glaucosity on the culm neck and on the spike than 'AC Vista'. 'Snowhite476' has a less spreading awn attitude than 'AC Vista'. 'Snowhite476' has a shorter spike length than 'AC Karma' and a longer spike than 'AC Vista'.


PLANT: spring type, growth habit intermediate between erect and prostrate (at booting)

SEEDLING (at four leaf stage): medium anthocyanin on the coleoptile, sparse pubescence on lower leaf sheath and blade

FLAG LEAF: medium frequency of plants with recurved flag leaves, very sparse pubescence on blade and sheath, medium to strong anthocyanin colouration on auricles, medium to strong glaucosity on sheath

CULM: neck with medium to strong glaucosity and very slight curvature

STRAW: pith thin in cross section, very weak anthocyanin at maturity

SPIKE: parallel sided to tapering in shape, medium density, incline to nodding at maturity, medium to strong glaucosity, white in colour

AWNS: present, medium to long, spreading attitude, white colour

GLUME: lower glume glabrous, shoulder straight to elevated with some slightly sloping, shoulder width ranging from very narrow to narrow, beak slightly curved to straight, beak length short to medium

KERNEL: hard white, large to medium in size, long in length, midwide in width, elliptical to broad elliptical in shape, cheek angular to rounded, brush hairs midlong, germ midsize to large in size and oval in shape, crease midwide and shallow to middeep

DISEASE REACTION: susceptible to Fusarium head blight (Fusarium graminearum, Fusarium species), resistant to Common bunt (Tilletia caries, Tilletia foetida), resistant to races T2, T10, T39 and susceptible to race T9 of Loose smut (Ustilago tritici), moderately resistant to moderately susceptible to Leaf rust (Puccinia triticina) and resistant to Stem rust (Puccinia graminia f.sp.tritici).

Origin & Breeding History: 'Snowhite476' originated from the cross HY398/HY423//5*HY393, made in 1997 at the Semiarid Prairie Agricultural Research Centre of Agriculture & Agri-Food Canada, Swift Current, Saskatchewan. The BC5F1 seed was inoculated with common bunt and planted as individual plants in the greenhouse. Seed from uninfected heads were grown in the greenhouse and as head rows in an out of season nursery near Christchurch, New Zealand. The BC5F3 and BC5F5 were screened for quantitative and qualitative traits in Saskatchewan and Manitoba. A single row of each BC5F3 line was grown in a bunt nursery from which bunt free heads were collected for inbreeding. Reaction to leaf and stem rust was measured in an epiphytotic nursery near Glenlea, Manitoba. Remnant seed from the yield trials was used to assess grain quality and kernel characteristics. Selected lines BC5F5 were inoculated with common bunt. An experimental line designated, P9711-PAE03B1 was evaluated in the High Yielding Wheat 'A' test in 2000. It was later designated as HY476 and evaluated in the High Yielding Wheat Cooperative test from 2001 to 2003.

Tests & Trials: 'Snowhite476' was tested for morphological characteristics at the Semiarid Prairie Agricultural Research Centre of Agriculture & Agri-Food Canada, Swift Current, Saskatchewan in 2003 and 2004. The trials consisted of four replications containing four rows, three metres in length. Spacing between rows was 23 cm and the seeding rate was 220 seeds per m2. A completely Randomized Block experimental design was used. Measured characteristics were based on 40 measurements.

Comparison tables for 'Snowhite476' with reference varieties 'AC Karma' and 'AC Vista'

Flag leaf length (cm)

  'Snowhite476' 'AC Karma' 'AC Vista'
mean 17.9 17.6 21.4
std. deviation 2.0 1.9 3.6

Flag leaf width (mm)

  'Snowhite476' 'AC Karma' 'AC Vista'
mean 16.5 14.8 15.1
std. deviation 1.3 1.1 1.0

Number of days to heading

  'Snowhite476' 'AC Karma' 'AC Vista'
days 61 61 57

Plant height (cm)

  'Snowhite476' 'AC Karma' 'AC Vista'
mean 87 86 82
std. deviation 5.4 5.9 7.6

Spike length (cm)

  'Snowhite476' 'AC Karma' 'AC Vista'
mean 9.8 10.2 9.3
std. deviation 0.5 0.6 0.6

Click on image for larger view
Wheat: 'Snowhite476' (left) with reference varieties 'AC Karma' (centre) and 'AC Vista' (right)

Date modified: