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Maize Growth in East and South-east
Asia – Challenges and Opportunities
Chinese Academy of Agricultural Sciences
Zhang Shihuang, Qiu Huanguang, Lu Kaiyv, Ci Xiaoke, Li Mingshun, Zhang Degui,
Liang Xiaoling, Xu Jiashun
National Maize Industrial Technology RD Center, MOA
Chinese Academy of Agricultural Sciences, Beijing, China
cshzhang2000@yahoo.com.cn
We Are Facing the Same
Challenges
demand and imports
production
breeding
seed industry
Chinese Academy of Agricultural Sciences
in Asia
Maize production in East and SE
Asia
Chinese Academy of Agricultural Sciences
Maize production in East and SE Asia (1961-2009) M
aiz
e o
ut
pu
t (m
illio
n t
on
)
y = 0.54x + 1.4
R2 = 0.91
y = 3.0 x + 3.9
R2 = 0.96
y = 3.0 x + 6
R2 = 0.96
0
20
40
60
80
100
120
140
160
180
1961
1964
1967
1970
1973
1976
1979
1982
1985
1988
1991
1994
1997
2000
2003
2006
2009
Eastern Asia South-Eastern Asia China
Maize production
in Asia has been
accelerating
during the past 2
decades due to
the increasing
and diversifying
demands for
maize
Maize Production in East and SE Asia
Asia 29%
71%
E Asia 165.89 71%
SE Asia 36.83 16%
other 31.58 13%
818.82
234.30 165.89
36.83
164.11
0.0
100.0
200.0
300.0
400.0
500.0
600.0
700.0
800.0
900.0
World Asia Eastern Asia
South-Eastern
Asia
China
Maize production (million ton) in East and SE Asia (2009) M
aiz
e p
rod
uc
tio
n (
mil
lio
n t
on
) East Asia is the
main producer of
maize in Asia
166 million tons
in 2009
20.2% of the
world’s total
maize production
Total maize output in Asia reached 234 million tons in 2009
accounted for one-fourth of the world total production
Maize production (million ton) in different areas M
aiz
e o
utp
ut
(milli
on
to
n)
0.00
100.00
200.00
300.00
400.00
500.00
600.00
700.00
800.00
900.00
1961 205.03 31.60 19.40 4.71 18.03
1990 483.34 132.47 101.33 16.44 97.21
2009 818.82 234.30 165.89 36.83 164.11
World Asia Eastern AsiaSouth-
Eastern AsiaChina
•Maize production in
East Asia comes
mainly from China
•accounted for 99%
of East Asia’s total
out put and 20% of
the world output in
2009
Maize Production in East and SE Asia
• Indonesia, the Philippines, Thailand,
and Vietnam are some other main
production countries of maize in
Southeast Asia
Incre
ment
(%)
Increment of maize production in the world, East and
SE Asia during 1961-2009 and 1990-2009
299
69
755
64
124
682
0
100
200
300
400
500
600
700
800
1961-2009 1990-2009
World
Eastern Asia
South-Eastern Asia
the average
growth rate of
maize
production in
East and SE
Asia is faster
than that of the
world average
Maize Production in East and SE Asia
• 1961~2009
• maize production and area increased by
2.99 times and 50% in the world
• but by 7.55 times and 101% in East Asia
• and by 6.82 times and 88% in SE Asia
Maize Production in East and SE Asia
• The growth rates of both yield and area have
been slowing down in the last 2 decades
• maize production increased by 69% in the
world, but increased by 64% and 124% in East
and SE Asia
• Maize area increased 21% in the world, but
43% and 7% in East Asia and SE Asia
Maize yield in East and SE Asia (1961-2009) M
aiz
e yie
ld (
To
n/h
a)
The trend of
maize yield
change in
East Asia was
contrary to
that in SE
Asia 0.0
1.0
2.0
3.0
4.0
5.0
6.0
Eastern Asia South-Eastern Asia China
y=0.11x+0.974
y=0.11x+1.0
y = 0.04x + 4.59
y = 0.03x + 4.58
y=0.03x+0.790
y = 0.1x + 1.64
Maize Yield in East and SE Asia
• Maize yield increased faster before 1990,
and have been slowing down since then
in East Asia (esp in China)
• However, it has increased faster in SE
Asia after 1990
• So the gap between East and SE Asia
has been being narrower after 1990
Maize Yield in East and SE Asia
• Maize yield increment was due to the:
– adoption of hybrids
– increase of inputs
Maize Yield in East Asia
• In East Asia (especially in China)
• maize yield increased by 220% with an
annual gain of 104 kg/ha during 1969-
1989
• but increased by 15% with an annual
gain of 35 kg/ha during 1990-2009
Maize Yield in SE Asia
• In SE Asia
• Maize yield increased by 99% with an
annual gain of 31 kg/ha before 1990s
• but after that, increased by 110% with
an annual gain of 99 kg/ha
Maize Yield in East and SE Asia
• Both the growth rate and the absolute
growth of maize yields in decades
showed a clear difference between East
and SE Asia
Yield gains of maize decreasing in China
Chinese Academy of Agricultural Sciences
(Data from FAO)
5.9%
4.5%
3.2%
0.2%
1960
1970
1980
1990 1.7%
2000
East Asia
4.4%
3.8%
2.7%
2.3%
1.9%
1960
1970
1980
1990
2000
SE Asia
Maize production in China
Chinese Academy of Agricultural Sciences
Year
kg/ha Maize yields since 1950s
OPVs
b=14
b=89 Double-cross hybrids
Single-cross hybrids
b=126 b=23
Stress tolerance
Chinese Academy of Agricultural Sciences
Maize Production in China
• Maize yield in China increased by 3.4
times, with an annual gain of 93 kg/ha
during the past 5 decades
Maize Production in China(略)
• It should be noted that maize yield in China
increased at 104 kg/ha/year before 1990s,
which was even higher than that in Argentina
• but after 1990, maize yield increased at 38
kg/ha/year which was much lower than the
growth of 152 kg/ha/year in US and 180
kg/ha/year in Argentina
• it was even lower than the gains in Vietnam,
Myanmar, Indonesia and Brazil (more than
100 kg/ha/year)
Maize yields in US, Argentina and China
0
2
4
6
8
10
12
America Argentina China
y=0.7x+1.6
y=0.11x+4.0
y=0.15x+7.0
y=0.11x+1.0
y=0.04x+4.6
y=0.18x+3.8
Maize Production in SE Asia
• On the contrary, maize yields have
increased sharply since the mid-1990s in
several SE Asian countries
• the annual gains of maize yield in
Indonesia, Vietnam and Myanmar are
4.1%，4.6% and 6.7%
• and annual gains of 107 kg/ha，143
kg/ha and 110 kg/ha
Maize Trade in the Region
Maize Trade in the Region
• Over the past half-century, the world
maize trade has increased significantly
• East Asia has been importing maize for
a long time, and the imports continue to
increase
• but some of the SE Asian countries
turned into maize exporters in the mid-
1980s
East Asia is a Net Importer (2009)
2008
54970-
9021-
16460-
220
-60000 -50000 -40000 -30000 -20000 -10000 0 10000
China
Japan
Korea
other part of the word
2008
South-east
Asia
7%
13%
South Korea
28%
Japan
52%
East Asia is a Net Importer (2009)
Maize Trade in the Region （略）
• Japan, Korea and China were the main
importers
• Maize imports in Japan (16-17 million tons
annually) accounted for more than half of
Asia’s total imports
• Korea (8-9 million tons) accounted for 28% of
Asia’s total imports
Maize Trade in the Region
• Imports of Japan and South Korea have
been relatively stable since 1990s
• China was a net export country in most
years
• but its export has been steadily
declining in the last decade
• China has become a net importer of
maize in 2010 (1.5 million tons)
Conclusion--1
• Asia is a big importer of maize
• Demand for maize will continue to
increase in Asia
Increase the Maize Production
to meet tremendous challenges
Small tractors for more
than 20 years and made
the soil hardpan
top fertility soil is
16.5 cm only
Prof. Zhang Dongxing
Soil Improvement
Improve the Soil
soil deep loosing tillage
to use subsoiler to break soil
hardpan
to increase top fertility soil
to return farm residue and crop
straw to the soil
Population density and machine
increase the population density in maize production
45,000/ha 60,000/ha
farming machine
new hybrids with stress tolerance and suitable to harvest machine
irrigation works
farmer collectives
36
Maize Yield and Population Density
t/ha bu/ac plants/ha plants/ac
1 16 10,000 4,047
2 32 20,000 8,094
3 48 30,000 12,141
4 64 40,000 16,188
5 80 45,000 18,211
6 96 50,000 20,235
7 112 55,000 22,258
8 128 60,000 24,282
9 144 65,000 26,305
10 160 70,000 28,329
11 176 75,000 30,352
12 192 80,000 32,376
13 208 85,000 34,399
14 224 90,000 36,423
Lamkey, 2007, Beijing
Stress tolerance
Suitable to harvest with machine
Maize Breeding Strategies in
East and SE Asia
• The rate of maize yield gains in China
has been reducing although the yield
potential has been increasing since
1960 when single cross hybrids were
introduced
Maize Breeding in China
• What is yield? -- questioned by Duvick
• Yield is stress tolerance !
• Stress tolerance of hybrids has been
ignored for almost three decades due to
the central planning economic
constitution of RD management
What is Yield?
40
Risky variety
Breeders tend to
develop hybrids
with tall stature, too
much leafy, late
maturity or full
season, and big
ears
most of this kind of
hybrids are risky
under stress
Plant and ear height (Beijing and Wulumuqi，2007-2008)
y = 3.71x + 249.5
R2 = 0.50
240
250
260
270
280
1950 1960 1970 1980 1990 2000
Pla
nt
heig
ht
(cm
)
Ear
heig
ht(
cm
)
Year of release
y = 1.15x + 105.4
R2 = 0.10100
110
120
130
1950 1960 1970 1980 1990 2000Year of release
Linear regression suggested that plant and ear height increased.
Maturity of hybrids delaied
66.0
67.0
68.0
69.0
70.0
71.0
72.0
1960 1970 1980 1990 2000 2010
Era (Year)
Matu
rity
(d
ay)
Low Mid High
Shelling percentage（2008）
y = -0.19x + 82.2
R2 = 0.03
75.0
80.0
85.0
1950 1960 1970 1980 1990 2000
Year of release
Sh
ell
ing
(%
)
Shelling percentage showed a trend to reduction during
1950s-2000s, especially reduced greatly during 1980s-2000s.
44 秃尖长度
y = 0.0889x + 0.6097
0.00
0.20
0.40
0.60
0.80
1.00
1.20
1.40
1950s 1970s 1980s 1990s 2000s
Year
Barr
ent tip (
cm
)
45 Pioneer hybrids 2006
46 Pioneer hybrids 2006
47
150,000/ha
Sept. 2011
have to change
row spacing
from 76 cm to 50
cm, to increase
the population
density
redesigning the
farming machine
Stine Seeds, Iowa
• Breeders also tend to develop hybrids
with excessive stay green and late
maturity during the past 4 decades
• caused application of chemical
fertilizers in a non-judicious manner
• reducing the efficiency of N utilization
Risky variety
Heterosis
• The contribution of heterosis to yield
gains is higher in China than that
reported in American hybrids
• the contribution of heterosis to yield gains showed
weak increase with the year of hybrids release
y = 0.09x - 107
R2 = 0.02
0
10
20
30
40
50
60
70
80
90
1960 1970 1980 1990 2000 2010
Het(%)
Year of release
66% 69%
Re
lative h
ete
rosis
(%
)
Heterosis incerased (1970-2000)
Chinese Academy of Agricultural Science
(11 environments, 2007-2009)
Schnell, F.W. 1974. Trends and problems in breeding methods for hybrid corn. p. 86–98.
In Proc. of the British Poultry Breeders Roundtable, 16th. Birmingham, England. 51
Duvick, D.N. 1999. Heterosis: Feeding people and protecting natural resources. p. 19–29. In J.G.
Coors and S. Pandey (ed.) The genetics and exploitation of heterosis in crops. ASA, Madison, WI. 52
Campbell, B.T., D.T. Bowman, and D.B. Weaver. 2008. Heterotic eff ects in topcrosses of modern and obsolete cotton cultivars. Crop Sci. 48:593–605. 53
Reorienting the Strategy
• Maize breeders both in China and SE
Asian countries are now actively
reorienting the strategy of maize
breeding, and develop stress resilient
and input responsive hybrids
Reorienting the Strategy
• increase yield potential
• enhance stress tolerance
• increase population density in both
crop production and breeding nursery
Strategies for breeding in Asia--1
• continue to introduce, improve and
utilize exotic germplasm to broaden the
genetic base in maize breeding
programs
• to enhance genetic variance in breeding
populations
• strengthen the pre-breeding efforts
Strategy --2
• germplasm should be divided into 2
heterotic groups or 2 alignments
• based on the current genetic
backgrounds, which will keep the SCA
effects in two groups
58
NSS
SS
Duvick, 2005
Strategy --3
• improve the germplasm within each
group and push them to the opposite
directions in terms of gene frequency
• which will enhance and accumulate
GCA effects in breeding populations of
germplasm
Strategy -- 4
• improve germplasm and select inbred
lines under high population density and
other stress conditions based on G×E
effects to enhance stress tolerance
• double density for inbred line
development
• plus 15,000/ha for evaluation of new
hybrids (Troyer,1981)
Strategy -- 5
• multi-location testing and information
management
• science and art
• data and experience
• modern machine and IP technology
• pipeline and profolio
Conclusion--2
• public
• private
• pre-breeding
• pipeline
• profolio
Conclusion--3
• improve the soil and infrastruture
• improve hybrids to meet challenges
• stress tolerance is more important than
heterosis for hybrid yields
• GCA is more important than SCA
• reorient the strategy of maize breeding
programs
Chinese Academy of Agricultural Sciences
Demand for maize in China - 2020
• 230 million tons by 2020
• Processing 58 mt (26%)
• Feeding stuff 151 mt (70%)
Chinese Academy of Agricultural Sciences
• Genetic yield (maximum) —The highest yield
record
• Attainable yield —average yield in Maize
Variety Regional Evaluation Trials
• Actual yield — statistic data issued by MOA
Three concepts of yield
227/120/127 860/95/30 Dr. RF Hu
Genetic yield Attainable yield Actual yield Attainable yield Actual yield Genetic yield Attainable yield Actual yield Genetic yield Attainable yield Actual yield
The differences between yields and yield potential
great
Attainable yield Actual yield Attainable yield Actual yield Genetic yield Attainable yield Actual yield Genetic yield Attainable yield Actual yield Genetic yield Attainable yield Actual yield Genetic yield Attainable yield Actual yield Attainable yield Genetic yield Actual yield Attainable yield Genetic yield Actual yield Attainable yield