MN55

Apple

Variety Description

Varieties used for comparison: 'Honeycrisp' and 'Minneiska'

Summary: The pubescence on the one-year-old shoots of 'MN55' is dense whereas that for 'Honeycrisp' is of medium density and that for 'Minneiska' is sparse. The one-year-old shoots of 'MN55' have many lenticels whereas those of 'Minneiska' have a few to medium number of lenticels. The fruit of 'MN55' is shorter than that of 'Minneiska'. The fruit of 'MN55' is ellipsoid to conic whereas that of both reference varieties is globose. The relative area of over colour on the fruit of 'MN55' is large whereas for 'Honeycrisp' it is small to medium sized and for 'Minneiska' it is medium sized. The intensity of the over colour for 'MN55' is strong whereas that for 'Honeycrisp' is weak to medium intensity and that for 'Minneiska' is of medium intensity. The fruit of 'MN55' has very few to few small lenticels whereas that of 'Honeycrisp' has medium to many medium sized lenticels and that of 'Minneiska' has many to very many large lenticels. The time of harvest and eating maturity for 'MN55' is early whereas for 'Honeycrisp' it is mid-season to late.

Description:

TREE: medium to strong vigour, ramified, spreading growth habit, fruit bearing on spurs and long shoots, begins flowering late, early fruit harvest and eating maturity

ONE-YEAR-OLD SHOOT: thin to medium thickness, reddish brown on side facing sun, dense pubescence on distal half, many lenticels

PETIOLE: very small to small extent of anthocyanin colouration from base
LEAF BLADE: outwards attitude in relation to shoot, medium to large length to width ratio, medium to strong intensity of green on upper side, serrate type 1 incisions of margin on distal half, medium density of pubescence on lower side

FLOWER: predominantly dark pink at balloon stage, overlapping arrangement of petals, stigmas positioned at same level as anthers

YOUNG FRUIT: absent or very small extent of anthocyanin over colour
FRUIT: medium sized, large height to diameter ratio, ellipsoid to conic shape, absent or weak degree of ribbing, absent or weak crowning at calyx end, medium length sepal
FRUIT SKIN: absent or weak degree of bloom, absent or weak degree of greasiness, yellow green ground colour, large relative area of over colour, strong intensity of brown red over colour, over colour distributed as solid flush with weakly defined stripes, narrow to medium width stripes, absent or small area of russet around stalk attachment, absent to small area of russet on cheeks, absent or small area of russet around eye basin, very few to few small lenticels
FRUIT STALK: thin to medium thickness
FRUIT STALK CAVITY: shallow to medium depth, narrow to medium width
FRUIT EYE: medium sized
FRUIT EYE BASIN: shallow, narrow
FRUIT FLESH: soft to medium degree of firmness, white coloured, moderately open aperture of locules in transverse section

Origin & Breeding History: 'MN55' originated from a cross conducted by the breeders, David Bedford and James Luby, in Excelsior, Minnesota, USA in 1997. The cross was made between the female parent variety 'Honeycrisp' and the male parent variety 'Monark' (also known as AA-44). 'MN55' was selected in 2003 based on time of harvest maturity, storage capability, fruit texture and flavour. Asexual reproduction of the new variety was first conducted by budding in 1998.

Tests & Trials: The comparative trial for 'MN55' was conducted from 2020 to 2021 at Summerland Varieties Corp. test plots, in Summerland, British Columbia. The trial consisted of 10 trees of 'MN55' planted in 2016 on MM111 rootstock, 10 trees of 'Honeycrisp' planted in 2012 on M9 rootstock and 10 trees of 'Minneiska' planted in 2008 on EMLA 26 rootstock. Trees were planted approximately 0.61 metres apart within a row and the rows were 3 metres apart. Observations and measurements were taken on 10 trees or 10 parts of trees for all varieties. Mean differences were significant at the 5% confidence probability level based on a paired Student's t-test.

Comparison table for 'MN55' with reference varieties 'Honeycrisp' and 'Minneiska'

Fruit height (cm)

Click on image for larger view

Apple: 'MN55' (top) with reference varieties 'Minneiska' (centre) and 'Honeycrisp' (bottom)