Under the C. Axis method, Fuji tends to assume “willowy”pendulous growth habit, particularly
on weak growing sites, dwarf rootstocks and under minimal pruning.From the general
observations in experimental and commercial plantings, uncontrolled C. Axis does not produce
satisfactory fruit quality.This decline in quality can be due to poor color, increased russet and
sunburn.

Properly spaced structural wood and fruiting laterals along the center leader in a pyramid shape
canopy contribute to good fruit quality.The main limbs are best positioned above horizontal and
up to 45º to allow more even light distribution for good color development.The incidence of
russet is also less apparent under this style of canopy management.

Preliminary observations in Tasmania to three levels of pruning on 10-year-old Fuji trees on
MM.106 showed no effect on fruit numbers and size.The light pruning treatment was equal to
an underpruned C. Axis.The medium pruning treatment was identical to normal chunk pruning,
shoot thinning and replacement of fruiting wood as usually practiced with C. Axis.The severe
pruning treatment included more vigorous chunk pruning, detailed shortening of all fruiting
wood and complete removal of 1-year-old shoots.

The medium and severe pruning levels had a beneficial effect on the level of russet (Table 8).
This effect could be due to changes in the position of main limbs and general tree shape, and an
increase in shoot regrowth, thus better protection for young fruits with larger foliage cover.
Flowers on young wood prolong the bloom period and provide an extended period for damage
by sprays and unfavorable weather during sensitive phases of fruit growth.General observations
in mature commercial plantings do indicate that more detailed hard pruned Fuji trees produce
better fruit quality in respect to skin finish.

In a number of hail-prone apple producing districts in Australia, hail netting is regularly installed
as a standard component of the production system.It has been observed in Queensland that the
netting can reduce russet, sunburn and limb rub due to the modifying effects of the hail netting
enclosure.

FERTILIZATION OF FUJI
A fertigation trial conducted at Grove Research Station has demonstrated some effects of
nitrogen and potassium on red color development in Naga-Fu 1 (Table 9).The area of red color
decreased with high nitrogen and under high nitrogen/potassium ratio.In addition to well-
established direct influence of nitrogen and potassium on red color in apples there is an indirect
effect.High nitrogen stimulates excessive shoot growth and causes poor color via reduced light
distribution within the tree canopy.

Nitrogen has generally been linked with the incidence of russet in Golden Delicious.This has
not been found to be the case in Tasmanian experiments on Fuji.

FRUIT MATURITY
In Australia, harvest of Fuji occurs during early to mid-April depending on location.In
Tasmania, it has been found that Fuji Naga-Fu 2 ripens 175 to 185 days after full bloom.This
occurs at about 145 days after the “T”stage of the fruit although, in warmer climates, harvest is
reported to occur after 115 days after “T”stage.“T”stage of fruit development is when the top
of the fruit is at right angles to its stalk.

Taste tests have determined that Fuji fruit harvested prior to optimum maturity have very poor
flavor and are unacceptable to the market.These results highlight the need for this cultivar to be
harvested at the correct maturity.

As with other apple cultivars, it has been found that the green background color, or ground color
of the fruit, changes from green to yellow as the fruit matured.It has been found, however, that
optimal harvest of Fuji occurs when the ground color is more yellow than other commercial
cultivars of apple.

A problem commonly encountered with Australian grown red Fuji is a dull brown skin color,
especially on young trees.This brown color decreases dramatically with increasing harvest
maturity which highlights the need to harvest Fuji apples as mature as possible to ensure
consumer satisfaction.

At optimum maturity there is a significant level of honey core (watercore) present in Fuji fruit.
Honey core has not been found to be associated with overmaturity or breakdown in storage of
Fuji.Indeed, it is now recommended that slight honey core be present in at least half the fruit at
the start of harvest.

Other indicators of fruit maturity such as fruit firmness, sugar levels and starch have not been
very useful in determining harvest maturity in Australia due to seasonal differences.Research
on predicting when to harvest Fuji is currently focusing on weekly changes in sugar, firmness
and starch levels rather than the actual values.

Sugar levels at optimal harvest maturity vary from 12% to 15%. Unlike Red Delicious, sugar
levels do not increase during storage because at optimal harvest maturity most of the starch in
the fruit has already been converted to sugars.

FUJI STORAGE
The Australian experience is that Fuji apples store extremely well, remaining crisp after
7 months of storage even in conventional coldrooms.Storage in a controlled atmosphere at 2%
oxygen and between 1 and 2% carbon dioxide has provided superior quality with fruit remaining
firmer than in air.Fuji fruits tolerate oxygen levels in storage below 1%, however, it is essential
to maintain carbon dioxide at lower levels than oxygen.

Australian grown Fuji fruit do not appear to suffer from bitter pit during storage.They are prone
to superficial scald especially if harvested early. Australian grown Fuji apples, harvested at the
end of the optimum period, are subject to increased incidence of core rot problems during
storage and appropriate control strategies must be employed.

CONCLUSIONS
Red Fuji is relatively widespread in new commercial plantings across all major growing regions
of Australia.It is grown in a diverse range of climatic and soil conditions which contributes to
variability in fruit quality and inconsistency in quality.The variety is site sensitive and can
produce unsatisfactory packouts of high quality fruit in some locations.

Fuji is a “high tech”cultivar that requires detailed and precise management and is not well suited
to the “ranch”style of management practiced in most countries outside Japan and Korea.

The most common Fuji selections in Australia are Naga-Fu 2 and Naga-Fu 1.Naga-Fu 6 and
Naga-Fu 12 are being used in most recent orchard developments.Further improved striped
strains will be adopted in future plantings.Medium vigor rootstocks MM.106 and N. Spy are
most frequently used by growers for semi-intensive C. Axis growing systems.

Fuji has some excellent characteristics which have encouraged growers to continue new
plantings.Excellent eating and keeping quality, time of harvest, wide window of harvest, fruit
size and productivity are its strongest points.Red Fuji appeals to consumers who prefer a firm
but sweet apple.It retains its firmness and its flavor during long-term storage.Early harvested
fruit, however, lack flavor and are prone to superficial scald.The best indicator of harvest
maturity is honey core (watercore) with harvest when at least 50% of the crop displays slight
honey core.

Inconsistent coloring characteristics, russet and, to an extent, crop regulation present the biggest
problems for the Australian growers.

IMAGE 02_Jotic01.gif

Table 1.The distribution in 1996 of apple varieties in Australia (Australian Bureau of Statistics).

Tree numbers
___________________
(x 1,000)%

Production
______________________
(metric tons)%

IMAGE 02_Jotic01.gif

Variety

Red Delicious and Delicious
Granny Smith
Golden Delicious
Fuji
Red Gala
Pink Lady
Others

3,008
1,114
510
735
821
809
1,546

35.2
13.0
6.0
8.6
9.6
9.5
18.1

103,303
77,286
26,512
9,073
8,767
7,646
47,634

36.9
27.6
9.5
3.2
3.1
2.7
17.0

IMAGE 02_Jotic01.gif

Total

8,543

280,221

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