Three main factors contribute to low yield.First, young trees do not bear as early as they should.
In China under excellent care young apple trees can reach yields of 10 MT/ha in 4 to 5 years
after planting.However, many young trees delay fruiting until 5 to 6 years, some even longer.
The initial output is less and the rate of yield increase is slower. Second, alternate bearing is a
serious problem in some orchards with an over 20% differential between on- and off-years.
Third, non-uniform trees exist in orchards, with a low proportion of trees which bear annually
and many low-yielding trees.

There are six reasons for low yields.First, inferior cultivars are within an orchard which are
either out-of-date or local low-yielding cultivars.Second, poor establishment practices are
common.Lack of soil improvement, noncertified nursery trees, poor orchard layout and
negligent care after planting cause a lower survival rate, a longer time for young trees to start
growing, inconsistent growth and weak tree vigor.Third, young trees are not managed properly
during the winters in the first several years after planting, causing freezing injury or “branch
drying”of some trees and resulting in inconsistent growth.Fourth, in some high-density
orchards, it is common to still use the training and pruning techniques for large canopies.By
using heavy pruning, too much heading-back pruning and maintaining upright branches, flower
bud formation is delayed.Heavy pruning results in a high proportion of long branches and
vigorous growth, delaying the beginning of bearing and reducing yield potential.There are
many orchards which become heavily shaded by intercrossing branches.With inferior air
circulation and sunlight distribution as soon as they start to bear, fruiting moves to the outer parts
of a canopy.The branches inside the canopy become weak, further affecting yield and fruit
quality.Fifth, the crop load is not controlled appropriately and thinning techniques are not
carried out carefully.Overcropping occurs commonly although fruit thinning has been done to
some extent.In this way, alternate bearing occurs because of the effect of overcropping on
flower bud differentiation.Sixth, poor fertilization and neglect of the balance of different
elements has affected the normal growth and flower bud formation of young apple trees.
Nitrogen use has been overemphasized, and phosphorous, potassium and other minor elements
have been overlooked.Low content of organic matter in soil, salinization and physiological
disorders due to deficiencies of Fe, Zn, B and Ca are also problems.

Inferior Quality
As the output of apples increases and living standards are raised, there is a higher demand for top
quality fruit.At present, the consumption is mainly fresh fruits, and the proportion of processed
apples is limited.Both external and internal qualities of fresh fruit are important as they
influence sales and grower profits.In addition to natural conditions and cultural measures which
control fruit quality, handling after harvest is also critical.Harvesting, sorting, packing, storing,
shipping, and selling are all important factors which affect fruit quality.

There are many causes of inferior quality in China.Many undesirable varieties are produced
with poor appearance and flavor.Some newer promising cultivars do not show their best
characteristics.For example, Red Fuji often produces an asymmetrical fruit with poor color,
rough appearance, small size, poor flavor, strong acidity, and coarse flesh.In the marketplace
there are fruits of different sizes, coloration, shape, even a mixture of different cultivars,
mechanically damaged, diseased, pest injured, or rotted fruits, so as to reduce market
acceptability and income.

The reasons for inferior quality include the following:1) excessive application of nitrogen, with
lower organic content in soil (at present the average organic content is only 0.6 to 0.8%); 2) poor
training and pruning, resulting in excessive growth with inferior air circulation and sunlight
within the canopy; 3) thinning of flowers and fruits is not done properly, resulting in serious
overcropping and uneven distribution of fruits in a tree; 4) diseases and insects are not controlled
in a timely way so that fruits, leaves, branches and limbs are injured seriously; 5) poor handling
after harvest, including poor sorting, packaging, shipment and storage; 6) lack of enough
advanced techniques (e.g., CA) and facilities for storage and transportation.

Popularizationand Extension of Growing Techniques
Apple is a species that needs much more care than other crops in order to obtain high yield and
top fruit quality at the same time.As the most important fruit crop in China, the apple industry
has a huge potential to develop further, considering its extensive acreage, production, and mature
growing technology.What is required now is to narrow the management difference between low
and high yielding orchards by improving the technical factors contributing to production.A new
extension education system must be established quickly because the original education system
for growers has broken down as a market economy has developed.Much work needs to be done
in the near future to establish social services and raise growers’ specialized skills by training and
guiding them in order to keep up with and surpass the advanced production levels in the world.

IMAGE 03_Zhang01.gif

Table 1.China apple acreage and production by province in 1996.

Land area
____________________________
(ha)(million acres)

Production

Yield

IMAGE 03_Zhang01.gif

Provinces

(metric ton)

(MT/ha)

Shandong
Shaaxi
Henan
Hebei
Liaoning
Shanxi
Gansu
Jiangsu
Xinjiang
Anhui
Beijing
Sichuan
Ningxia
Heilongjiang
Tianjin
Yunnan
Jilin
Hubei
Inner Mongolia
Qinghai
Guizhou
Xizang
Zhejiang
Fujian
Total

663,300
470,200
341,300
384,800
261,400
191,700
211,500
78,900
45,400
42,400
23,100
34,500
31,500
31,230
13,200
47,200
20,500
13,500
35,800
4,500
7,200
1,400
400
200
2,986,930

1.639
1.161
.843
.950
.646
.474
.523
.195
.112
.105
.057
.085
.078
.077
.033
.117
.050
.033
.088
.011
.018
.003
.001
.0005
7.380

6,056,428
2,958,884
1,820,507
1,566,759
1,505,993
919,660
515,083
440,737
247,444
218,354
172,088
138,831
109,159
78,073
71,164
65,763
57,618
42,984
39,200
18,935
4,785
3,049
611
137
17,052,246

9.10
6.29
5.30
4.07
5.76
4.79
2.44
5.59
5.45
5.15
7.45
4.02
3.47
2.50
5.39
1.39
2.81
3.18
1.09
4.21
0.66
2.18
1.53
0.69
5.70

IMAGE 03_Zhang01.gif

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