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INITIAL
REPORT ON CHINA NATIONAL SRI WORKSHOP
Hangzhou,
March 2-3, 2003
by Norman Uphoff, CIIFAD
A more extensive
report is being prepared by the China National Rice Research Institute
(CNRRI) which organized this workshop in Hangzhou. It was cosponsored
by the China National Hybrid Rice Research and Development Center
(CNHRRDC) and the Zhejiang Provincial Department of Agriculture,
the province in which CNRRI is located.
Opening Session:
The workshop chairman, Dr. Zhu Defeng (CNRRI), opened the event
by thanking the participants from various research institutes, universities
and extension departments for coming. He noted that SRI research
has already demonstrated the system's validity in many different
ecosystems in China and then reviewed the purpose and mission of
the workshop.
The workshop
was opened with several introductory talks, starting with Dr. Wang
Qingli from the Ministry of Agriculture in Beijing. He discussed
changes going on in the agricultural sector, particularly with China's
entry into the WTO, and the Ministry's growing concern for impacts
on the environment. He suggested that SRI would be very compatible
with China's planned "adjustment of the agriculture structure and
eco-agriculture." This strategy includes the use of best varieties
and reductions in the use of fertilizer and water. He suggested
that participants consider how to make SRI easier for farmers to
learn. He said that the Ministry would continue supporting research
and work on SRI according to its results.
Prof. Zhang
Hongfang, deputy director of the Zhejiang Department of Agriculture,
spoke next, discussing how the rice sector is changing in Zhejiang
province. About 80% of the rice area is now single-cropped, with
other crops being grown in alternation with rice. This is a favorable
situation for SRI since such crop rotation is ideal for this system.
SRI can give a higher yield from a single crop of rice in part because
growing vegetables or pulses in between rice crops improves soil
fertility for rice.
Dr. Zhu Deqi
from the Zhejiang Department of Science and Technology emphasize
that rice is the biggest crop in the province. SRI, he said, should
be especially good for non-rich farmers, being a "simple" technology
and one that should be easier to disseminate than more complicated,
input-dependent technologies. He said that his department looked
forward to getting information on SRI from other provinces and other
countries from the workshop.
Prof. Liao Xiyuan,
deputy director of CNRRI, standing in for the Institute's director-general
who had to be in Beijing, observed that good land area for rice
production is declining because of urban expansion and soil degradation,
so it is important to raise yields. He said that increased quality
of rice is also sought, adding that there is need for more support
of research. He put in a plug for my presentation on SRI scheduled
for the afternoon, saying it would "open our minds."
Dr. Ma Guohui,
deputy director of CNHRRDC, then spoke on behalf of his Center,
apologizing that its director, Prof. Yuan Longping, could not be
present since he is attending the People's Consultative Congress
in Beijing. He said Prof. Yuan is very happy about this workshop.
This was an important endorsement for SRI since Prof. Yuan, regarded
as "the father of hybrid rice," is China's best known rice scientist.
Dr. Ma said that SRI is showing that the management of rice is as
important as breeding.
Dr. Zhang Hongcheng
from Yangzhou University also spoke in this opening session, but
I had no translation of his comments. After his comments, we adjourned
for a group picture.
Morning
Technical Session: When the workshop regrouped, I made a brief
comment to introduce the subject of SRI. I underscored that this
system is not a single thing and should be seen as 'a work in progress.'
I suggested a historical comparison between SRI development and
the development of aviation, noting that Fr. de Laulanié's
first SRI harvest in 1983-84 in Madagascar was like the Wright Brothers'
flight at Kitty Hawk 100 years ago. This was the equivalent for
rice of breaking the constraint of gravity by a heavier-than-air
craft. After 20 years, SRI is now a serviceable system, reliable
enough to be compared with the old DC3 aircraft that was the workhorse
of the aviation industry for many years. But it was still a propeller-driven
craft, as with current SRI methods we can get an average yield around
8 t/ha.
Airplanes were
rapidly and variously developed during the first part of the 20th
century, with improvements in wing design, engine power, navigation
systems, etc. There were British planes, French planes, Russian
planes, Chinese planes, etc., and different models within each country.
We can see SRI similarly proliferating today, to everyone's advantage.
No single model is needed or desirable.
The biggest
advance in aviation during the past century came with the development
of jet propulsion, to power larger planes faster. I suggested that
this kind of transition is still to be made with SRI, though some
of the "super-yields" attained with SRI show that much better performance
is still possible. Better understanding and management of soil microbial
activity could give SRI a large further boost, equivalent to jet
propulsion. But this remains conjecture, not established scientifically.
I said that I would discuss this subject more in the afternoon.
Dr. Zhu Defeng
of CNRRI, who had taken the initiative to organize the workshop,
then started the session off with a report on his institute's SRI
research. He said that the rice sector should seek (a) to overcome
the problem of declining yields, (b) to reduce the requirements
for water and for fertilizer and chemicals (the latter adversely
affecting water quality), (c) to improve the environment (including
reduction in methane emissions from flooded paddies), (d) to increase
resource efficiency in rice production. He briefly reviewed the
history of SRI, starting from Fr. de Laulanié's experiments
in 1983, saying that SRI had been introduced to China by Prof. Uphoff.
Results so far have ranged from 10.6 to 16.0 t/ha, showing that
SRI has great potential.
Dr. Zhu then
focused on his own research on phyllochrons in rice, also referred
to as leaf number. It was exciting to see his confirmation of Laulanié's
work 15 years earlier, showing the different numbers and contributions
of primary, secondary and tertiary tillers. He presented data showing
different patterns of light penetration into the rice canopy with
SRI vs. conventional spacing. It was clear that SRI practices give
greater illumination to all levels of the canopy.
Dr. Zhu acknowledged
that SRI requires more labor at the beginning, but this can be reduced
with experience. Water control is another requirement, though this
should not be a great problem in much of China, where reducing water
off-takes for agriculture is becoming an imperative. There does
need to be more knowledge for effective SRI, both on the part of
farmers and researchers.
Improvements
in SRI that he envisioned as being are particularly relevant for
China are:
- use of plastic
trays for planting and transplanting seedlings (minimizing root
disturbance and saving labor);
- finding optimum
combinations of chemical fertilizer and compost;
- developing
raised-bed cultivation and furrow irrigation;
- identifying
the best rice varieties with high tillering ability; and
- innovations
in spacing, such as the triangular pattern already devised in
Sichuan.
Dr. Ma Guohui
of CHNRRDC then reported on his Center's evaluation of SRI used
together with its hybrid varieties. The Center began evaluating
SRI since 2000-2001. The triangular pattern of planting that Dr.
Zhu had referred to was developed by a seed farm associated with
the Hybrid Rice Center. It has given better results than single
seedlings in a grid pattern in 7 out of 10 trials. The Center finds
that using various seedbed media with plastic trays or paper containers
gives good results. It has also experimented with a paper template
when planting seedbeds to space single seeds more evenly. This offers
some advantages. He showed a picture of a weeder that piles up a
little soil around the culm (base) of the plant, and this appears
to reduce senescence of leaves. Dr. Ma reported a similar range
of yield results for SRI methods as did Dr. Zhu.
The improvements
he suggested were also similar to Dr. Zhu's:
- use of trays
for seedling planting and transplanting;
- combining
compost and chemical fertilizer;
- combining
herbicides with use of the mechanical hand weeder that aerates
the soil;
- mechanization
for transplanting and weeding; and
- finding ways
to increase tillering, through breeding and/or soil and water
management.
In the discussion
that followed, one of the questions raised was whether SRI affects
the quality of the grain. Someone responded that using organic fertilization
improves rice quality, and someone else added that his evaluations
have shown that SRI methods reduce chalkiness. A question was asked
about possible changes in the harvest index with SRI. Dr. Ma said
that no decrease had been found, and that with modified SRI, there
are both more roots and more sink capacity. The morning session
concluded promptly at noon, and we adjourned for a splendid lunch
upstairs.
Afternoon
Technical Session: Dr. Ma Jun from the Rice Research Institute
of the Sichuan Agricultural University began with a report from
this province which has the most practical experience with SRI so
far. The Sichuan Academy of Agricultural Sciences is in its third
year of evaluations. Its field trials in four locations during 2002
gave an average yield of 13 t/ha. Dr. Ma said that rice breeding
efforts in China have produced and released many improved varieties,
but there has been little impact on overall productivity from this.
In Sichuan,
they have encountered some difficulties with SRI when 15-day-old
seedlings are still too young for the colder temperatures. Also,
sometimes it is difficult to get enough organic fertilizer to use
instead of chemical fertilizer. They have been using weedicides
with SRI because of labor constraints. He said that the seed-set
rate with SRI has often been lower (though in my view this could
be because chemical fertilizer and herbicides are being used). The
various trials have shown a 6.4-16.3% increase with SRI methods,
and in one case, a 7.7% decrease, compared with control plots.
Dr. Ma showed
data confirming that younger seedlings give higher yield, other
things being equal (not reflecting the synergies that are possible
when using the full set of SRI practices). Also data showed better
results with a combination of chemical and organic fertilization,
though the best results reported came from using organic fertilizers
together with microorganisms. He showed a picture of a farmer "swimming"
in his rice field, with plants up to his shoulders. He commented
that although biomass is greatly increased, there was no evident
problem of lodging.
Dr. Ma then
showed data on reduced chalkiness of rice grains with SRI methods
and on increased length of panicle (147 vs. 114 cm), adding also
that less disease was seen with SRI. There are larger root systems
with SRI, and increased quality of root exudation. He concluded
with some economic data from their demonstration areas. With SRI
methods, the increase in profitability/hectare was between 1,135
and 3,567 yuan, i.e., between $150 and $450/hectare.
Dr. Ma summarized
the "essence" of SRI as single plants, wide spacing, less water,
and more attention to the root system. He said they have already
formed an organization in Sichuan to promote work on SRI with 5
institutes cooperating. They want to focus on how to make it easy
for farmers to learn and use SRI.
The next speaker
was Dr. Yao Kemin from the Nanjing College of Meteorology, who had
done an analysis of SRI's suitability for different regions within
China according to temperature and other factors. His data did not
show much or any advantage to using SRI methods. According to him,
SRI should reduce harvest index and yield. His conclusion was that
SRI will be suitable only in the south of China such as Hainan,
Guangdong and Guizhou, where the climate is more like that in Madagascar.
This was at variance with the report just made from Sichuan province,
where SRI was being used successfully despite a colder climate.
Indeed, the highest SRI yield so far achieved in China, 16 t/ha
officially certified, is from Sichuan province, not Hainan.
Dr. Jin Xueyong,
director of the Research Institute of North East Agricultural University
(NEAU), reported on SRI experimentation and evaluation in Heilongjiang
province. His pictures of vigorous SRI rice growing in the north
also contradicted Dr. Yao's climatological assessment. At NEAU they
have made, appropriately, some modifications in SRI practices because
of the colder temperatures. Pictures were shown of rice seedbeds
being started in plastic-covered greenhouses. The data presented
were shown quickly and I did not have translation of their explanation,
but they appeared to show yields in the range of 10.3-11.68 t/ha.
Dr. Tao Longxing
from CNRRI made a presentation on the physiological characteristics
of SRI, which he has been studying at the Institute. Like Dr. Zhu,
he contributed a very interesting paper to the international SRI
conference held in April 2002 at Sanya. It was interesting that
Dr. Tao's data showed leaf area greater with SRI than the control,
but leaf area index greater with the control than with SRI.
Root dry weight was greater both at heading (13.2 vs. 8.2 g/hill)
and at ripening (7.6 vs. 5.2 g/hill). Root penetration reached to
55 cm vs. 35 cm. The root pictures shown by Dr. Tao gave visual
evidence of the large differences in root development with SRI.
There were big
differences in tillers/hill: at the peak, 50 with SRI (single seedlings)
vs. 20 with the control (multiple seedlings). The SRI plants showed
greater height throughout the growth cycle. There were similarly
large differences in size of shoots and panicles, with seed-set
remaining high with SRI plants and falling to zero with the control.
Dr. Tao's research did not evaluate yield differences, only measuring
and documenting the physical differences in plant growth patterns
that correlate closely with the yield results that others were reporting.
My presentation
reviewed briefly the principles and practices of SRI, and then its
history and spread beyond Madagascar. China was the first country
outside of its country of origin where SRI was evaluated: at Nanjing
Agricultural University in 1999. Then, in 2000-2001, the China National
Hybrid Rice Center under its director Prof. Yuan tried out SRI methods
and encouraged CNRRI, the Sichuan Academy of Agricultural Sciences
and other institutions to do their own evaluations. This workshop
has grown out of the encouraging results of these trials and reflects
a increasing interest in SRI in China.
In the time
I had been given, I focused on kinds of changes in soil microbiology
that could be contributing to the higher yields being achieved with
SRI methods. These increase root growth through the use of young
seedlings, wider spacing and aerated soil. These conditions are
in turn probably supporting soil microbial abundance and diversity
through root exudation. I showed one data set from Madagascar that
supported this tentative conclusion. I suggested that:
- Biological
nitrogen fixation (BNF) can occur in rice roots and the rhizosphere,
contrary to the idea that BNF occurs only with leguminous plants;
there is research showing that BNF increases when aerobic and
anaerobic soil horizons are mixed (Magdoff and Bouldin 1970);
- P solubilization
increases in soil that is wetted, dried and rewetted, by very
large percentages (Turner and Haygarth 2001);
- Mycorrhizal
fungus "infections" of plant roots greatly increase the amount
and variety of nutrients accessed by roots; this symbiotic association
benefits 80-90% of plants, but not continuously irrigated rice
because soil fungi cannot grow under hypoxic conditions;
- Rhizobia
in the rhizosphere of rice increase yield and protein content
per hectare, not through BNF, as these bacteria do in the nodules
of legumes, but through production of auxins and other growth-promoting
substances (Yanni et al. 2001);
- Protozoa
that "graze" on bacteria living on the roots of plants exude N
on the roots' surface because they require a lower C/N ratio than
contained in the bacteria (Pinton et al. 2000).
Root exudation
is probably a key factor in these various processes, as with SRI
methods of plant, soil, water and nutrient management, canopies
and root systems of rice are much larger. These should produce more
exudate and increase rhizodeposition. There is little scientific
research on these processes in rice, however, mainly because rice
has been grown mostly under flooded conditions. In anaerobic soil,
many of these processes are inhibited or suppressed. Consideration
of soil microbiological contributions to increased rice production
opens up some promising areas for research and for improved production
practices. We think a better understanding of soil microbiological
contributions to rice could also help improve the production of
other crops.
Ms. Mao Guoquan
from the Zhejiang Department of Agriculture spoke next. She said
that 9 institutes in her province have been doing SRI experiments,
with yield increases of 13-34%. I did not get all of her points
because her remarks were not completely translated for me, but her
conclusions were that SRI is very suitable for Zhejiang Province;
it is very good for the environment, a growing concern; it gives
good grain quality, and there is less cost of production. Finally,
she commented that the system is "easy" for farmers to adopt. I
could not tell whether this was a statement of experience in Zhejiang
or a prediction based on what they know of SRI.
Dr. Zhang Hongcheng
from Agricultural College of Yangzhou University reported on three
years of trials. These have shown that one plant per hill is best,
and that SRI methods produce more grains per panicle. I could not
get all of the information he presented, but the yield of 674.7
kg/mu that he reported with SRI methods amounts to a yield of 9.7
t/ha, a 13.1% increase over the control shown. Another result reported
with 20x30 cm spacing represents a yield of 10.5 t/ha.
Dr. Zhang Yuzu
from the Hainan Rice Research Institute reported that with SRI methods
in direct-seeded rice, weeds become a problem and need to be controlled
by chemicals or by hand. Sparser planting (lower plant density)
gives higher yield. He said that with the merits of SRI being clear,
the next step is to develop improved and simplified methods of SRI.
His institute recognizes that root growth is particularly important
and is trying to promote this by SRI. It is now working on methods
for raised beds and ridging.
Dr. Wang Xiehui
from the Anqing Regional Agricultural Institute in Anhui spoke next.
I did not get much from this presentation because I had no translation,
but the Anhui presentation at the Sanya conference in April 2002
provided some of the strongest Chinese evidence of benefits from
SRI practices.
To conclude
the afternoon, Mr. Liu Zhibing, farm manager of the Meishan Seed
Company in Sichuan province, reported on his experience with SRI.
He has had yields of 15.996, 15.572 and 15.6 t/ha with seed-set
rates around 90%, with panicles having 185-190 grains each. He discussed
the "triangular" method of seed transplanting that he has devised,
planting three seedlings per hill but having only half as many hills
as in a standard SRI grid pattern because the hills are alternated.
This gives 50% more tillers per hectare than with usual SRI practice
of single seedlings per hill. His rice plants averaged 80 tiller
at 60 DAT, half of which became fertile with an average of 250 grains
per panicle. He rotates his rice crop with a potato crop, and he
is now experimenting with inserting a crop of rape into the cycle
as well. The photographs of his rice crops were very impressive,
and his enthusiastic presentation held participants' attention even
though, with so many reports, his report did not finish until after
5 o'clock.
With the workshop
was well beyond its scheduled time to conclude, Dr. Ma Guohui gave
a very clear and concise summary of the afternoon's presentations
before the participants adjourned for the workshop's gala supper,
with good food, drinks and camaraderie.
Planning
Session: The next morning, the participants reconvened in two
discussion groups, one focusing on research issues and priorities,
and the other on extension strategies and methods. (Since I could
not follow the discussions in Chinese, I went to Zhejiang University
to make a presentation on SRI to students and staff in the College
of Environmental and Natural Sciences.) In the afternoon, each group
reported the results of its discussion in a plenary meeting, and
Dr. Zhu summarized the workshop conclusions before closing. There
were workshop participants from 11 provinces who contributed to
the planning efforts.
CNRRI already
has a web site for SRI. This will be further developed. There should
be a lot more data on SRI experience generated during the present
year 2003 to put on it. Various modifications and innovations in
the basic SRI methodology will need to be made to suit different
Chinese conditions. The web site will disseminate innovations and
evaluations thereof.
There is agreement
that reduced water application and good water control, young seedlings,
wider spacing, and soil improvement with changes in fertilization
to improve soil microorganisms will lead to greater and more sustainable
rice production in China. One of the objectives of SRI development
will be to reduce water pollution by reducing the use of chemical
fertilizers and agrochemicals and to increase water use efficiency.
There is need to devise a better rice agroecosystem that can be
adapted to local conditions.
The creation
of a national SRI network was agreed upon. It will be coordinated
by Dr. Zhu Defeng of CNRRI and will have a steering committee headed
by Dr. Zhu and Dr. Ma Guihui of CNHRRDC. Its membership includes:
- Prof. Ma
Jun from Sichuan Agricultural University,
- Prof. Zhang
Hongcheng, chairman of the College of Agriculture of Yangzhou
University in Jiangsu Province,
- Prof. Jin
Xueyong, director of the Rice Research Institute of the Northeast
Agricultural University in Heilongjiang province, and
- Prof. Sun
Jian, director of the Crop Management Division, Zhejiang Department
of Agriculture.
The steering
committee on behalf of the network will seek to mobilize increased
financial support from government sources and donor agencies for
research and extension work on SRI, will set up research priorities,
and will organize meetings and other activities as needed.
It was agreed
that all participants will undertake research and demonstration
activities on SRI in different ecosystems and will develop adaptations
of SRI suitable for their environments using whatever resources
can be obtained at present, so that the understanding and practice
of SRI in China begins to expand. Any increased support that can
be obtained from government and other sources will accelerate this
process and enable participating institutions to spread faster the
benefits of SRI for people and for the environment.
POSTSCRIPT:
After the Hangzhou workshop, I spent a week with the College of
Humanities and Development of China Agricultural University in Beijing,
since I serve on its external advisory committee. I was able to
meet with Prof. Qu Dongyu, vice president of the Chinese Academy
of Agricultural Sciences, who oversees the work of CNRRI and many
other research institutions, to brief him on the workshop and tell
him more about SRI. I was not able to meet the president of the
Academy, Prof. Zhai Huqu, formerly president of Nanjing Agricultural
University, and the first sponsor of SRI trials in China, because
the Chinese People's Consultative Congress was in session. But I
provided Prof. Zhai with a copy of the Sanya conference proceedings.
I also met with
Prof. Jin Yimin, director in the Department of Rural and Social
Development in the Ministry of Science and Technology, and Ms. Meng
Jiandong, deputy chief of staff in the Ministry, whom I had told
about SRI in August 2002 when she visited Cornell with a MOST delegation.
They are now also interested in SRI. Dr. Zhu from CNRRI will follow
up with both CAAS and MOST as well as the Ministry of Agriculture.
I was also able
to speak at length by phone with Dr. Cao Weixing, senior administrator
at Nanjing Agricultural University, who actually did the first SRI
trials with Dr. Ding Yanfeng in 1999. Cao had planned to attend
the Hangzhou workshop, but he is now a member of the People's Consultative
Congress, as vice-president of the Jiangsu Provincial Consultative
Congress. His presence was required in Beijing. He expressed his
strong interest in continuing to work with SRI and with colleagues
in the SRI network both in China and internationally. Dr. Ding is
now back at NAU after doing a PhD program in Japan, and he will
provide leadership for SRI research in Nanjing.
After the workshop,
Mr. Liu, farm manager of the Meishan Seed Company in Sichuan, gave
me a beautiful, full-color, plasticized sheet with pictures of his
spectacular SRI plots, one of which was certified by the Provincial
Department of Agriculture as having produced a yield of 16 t/ha.
The sheet also had pictures of him with the trophy and certificate
he received for his accomplishment, of him with Prof. Yuan who introduced
SRI methods to him, of him with me during a visit to his farm last
September, and of President Zheng Zimin addressing the International
Rice Congress last year, talking about the need to increase rice
productivity in China. Liu is promoting SRI within his province
and beyond. With someone so motivated and talented publicizing SRI
at his own initiative, and with results like his to publicize, the
prospects for SRI look good in China, over and above what the new
SRI network will be able to achieve.
*
* * * *
Following the
workshop, I spent a week in Beijing with the College of Humanities
and Development at China Agricultural University, for which I serve
as chair of its external advisory committee. During this time, I
had an opportunity to meet with Dr. Qu Dongyu, vice-president of
the China Academy of Agricultural Sciences (CAAS), who has oversight
for CNRRI and a number of other such institutions. I briefed him
on the workshop and said that Dr. Zhu would follow up with more
information. Because the National People's Consultative Congress
was in session, I was not able to meet with Dr. Zhai Huqu, president
of SAAS and former president of Nanjing Agricultural University
(NAU). He hosted the first seminar I was able to give on SRI at
that university, and as a prominent rice breeder he took an interest
in SRI, supporting the first trials in China. We hope to have his
continuing interest.
I was also able
to meet with Dr. Jin Yimin, director in the Department of Rural
and Social Development of the Ministry of Science and Technology
(MOST), and Ms. Meng Jiandong, deputy chief of staff in MOST, to
report on the workshop. Madam Meng visited Cornell in August 2002
with a MOST delegation and took an interest in SRI. We hope that
this ministry as well as the Ministry of Agriculture will give support
to the expanding work on SRI in China.
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