Denomination: 'HW620'
Botanical Name: Pyrus communis
Applicant/Holder: Agriculture & Agri-Food Canada, Vineland
Research Farm - Vineland
4902 Victoria Avenue North, P.O. Box 6000
Vineland, Ontario
L0R 2E0
Breeder: David Hunter, Agriculture & Agri-Food Canada, Vineland, Ontario
Agent in Canada: Agriculture & Agri-Food Canada
Office of Intellectual Property and Commercialization
6000 C&E Trail
Lacombe, Alberta
T4L 1W1
Tel: (403) 782-8126
Application Date: 2010-04-30
Application Number: 10-6952
Grant of Rights Date: 2012-09-06
Certificate Number: 4401
Grant of Rights Termination Date: 2030-09-06

Variety Description

Varieties used for comparison: 'Bosc', 'Harrow Sweet', 'AC Harrow Crisp' and 'Bartlett'

Summary: The fruit of 'HW620' is large to very large whereas the fruit of 'Harrow Sweet' is medium sized and 'Bartlett' is medium to large. There is no overcolour on the fruit of 'HW620' whereas there is an orange red overcolour of a small to medium amount on 'Harrow Sweet', medium amount on 'AC Harrow Crisp' and very small amount on 'Bartlett'. 'HW620' has no russetting around the eye basin, on the cheeks or around the stalk attachment whereas 'Bosc' has a large to very large amount on these areas of the fruit. The fruit stalk of 'HW620' is shorter than those of the reference varieties. The fruit of 'HW620' has a thick stalk whereas it is thin to medium on 'Bosc' and medium thickness on 'Harrow Sweet' and 'AC Harrow Crisp'. 'HW620' has no curvature of the stalk whereas it is medium to strong on 'Bosc', weak to medium on 'Harrow Sweet' and medium on 'AC Harrow Crisp'. 'HW620' is harvested very late whereas 'AC Harrow Crisp' is harvested mid to late season and 'Bartlett' is harvested mid-season. 'HW620' is resistant to moderately resistant to Erwinia amylovora whereas 'Bosc' is moderately susceptible and 'Bartlett' is susceptible.


TREE: medium to strong vigour, medium to strong branching, semi-upright habit, starts flowering early to mid-season, very late maturity for consumption

ONE YEAR OLD SHOOTS: wavy growth, predominantly brown red colour on sunny side, medium to many lenticels
VEGETATIVE BUD: acute apex, slightly held out in relation to the shoot, medium size bud support
YOUNG SHOOTS: strong intensity of anthocyanin colouration of growing tip, weak to medium density of pubescence on upper third

LEAF: downwards attitude in relation to shoot, medium size length/width ratio, right angled to obtuse base, right-angled apex, very short pointed tip, bluntly serrate margin, shallow incisions, medium curvature of longitudinal axis
STIPULES: present, short to medium distance from basal attachment

FLOWER: mainly on spurs, stigma positioned below level of stamens
SEPALS: recurved in relation to corolla
PETALS: touching, small, circular shape, rounded base, short to medium length claw

FRUIT: medium length/diameter ratio, position of maximum diameter slightly towards calyx, large to very large size, mainly slightly asymmetric in longitudinal section with some symmetric, concave profile of sides
SKIN: mainly green with some yellow green ground colour, no over colour, absent or very small area of russetting around eye basin, on cheeks and around stalk attachment
STALK: thick, absent or very weak curvature, straight to oblique attitude in relation to axis of the fruit, shallow to medium depth of stalk cavity
EYE BASIN, AT HARVEST: converging sepals, shallow to medium depth, narrow, embossed relief around eye
FLESH: very fine texture, soft to medium firmness, juicy to very juicy
SEED: ovate

DISEASE REACTIONS: resistant to moderately resistant to fire blight (Erwinia amylovora)

Origin & Breeding History: 'HW620' arose from the controlled cross of 'Devoe' and 'Potomac' made in 1972 by Dr. H. A. Quamme at the Agriculture and Agri-Food Canada Research Station in Harrow, Ontario. It was selected by Dr. F. Kappel as a hybrid seedling in 1984 and propagated by budding on pear seedling rootstocks. Trees were planted in an evaluation orchard at the Harrow Research Centre in 1993 and in November, 1999, trees in this orchard were relocated to the Agriculture and Agri-Food Canada Research Farm at Jordan Station, Ontario. This selection was advanced by Dr. D. M. Hunter and made available for testing, as 'HW620', in regional trials in cooperation with the Western Ontario Fruit Testing Association beginning in 1994.

Tests & Trials: The tests and trials for 'HW620' were conducted during the 2009-2010 growing seasons at the Jordan Farm of Agriculture and Agri-Food Canada Research Centre in Jordan Station, Ontario. The trials consisted of a minimum of 4 trees per variety spaced 3 metres apart in the row and 4.5 metres apart between rows. The trees were grafted on standard 'Bartlett' rootstock and were originally established during the 1999 growing season.

Comparison tables for 'HW620' with reference varieties 'Bosc', 'Harrow Sweet', 'AC Harrow Crisp' and 'Bartlett'

Fruit length (cm)

  'HW620' 'Bosc' 'Harrow Sweet' 'AC Harrow Crisp' 'Bartlett'
mean 9.8 10.2 9.1 9.1 9.0
std. deviation 1.0 0.9 0.9 0.8 0.9

Fruit maximum diameter (cm)

  'HW620' 'Bosc' 'Harrow Sweet' 'AC Harrow Crisp' 'Bartlett'
mean 7.1 7.0 6.6 6.8 6.8
std. deviation 0.6 0.5 0.6 0.6 0.6

Length of fruit stalk (cm)

  'HW620' 'Bosc' 'Harrow Sweet' 'AC Harrow Crisp' 'Bartlett'
mean 2.3 5.0 3.4 3.7 2.8
std. deviation 0.5 0.7 0.6 0.9 0.6

Click on image for larger view
Pear: 'HW620' (left) with reference varieties 'Bosc' (top centre), 'AC Harrow Crisp' (top right), 'Harrow Sweet' (bottom centre) and 'Bartlett' (bottom right)

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