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Project information
»Funding dates
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Original grant (2001-2005)
Yr 1: 12/1/2001-11/30/2002
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First renewal (2005-2009)
Yr 5: 12/1/2005-11/30/2006
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Yr 2: 12/1/2002-11/30/2003
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Yr 6: 12/1/2006-11/30/2007
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Yr 3: 12/1/2003-11/30/2004
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Yr 7: 12/1/2007-11/30/2008
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Yr 4: 12/1/2004-11/30/2005
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Yr 8: 12/1/2008-11/30/2009
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Great scientific, ecological,
and human effects are expected from this research project. |
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»The problem
Food legumes have a unique potential to improve both human
nutrition and agricultural sustainability; they provide a
high-quality source of nutrients, N inputs through biological
nitrogen fixation, and are considered a high-value crop for
marketing. However, their potential frequently goes unrealized
in some of the poorest regions of the world, where the predominance
of highly weathered tropical soils constrains legume productivity.
Most legumes perform poorly under low fertility conditions,
especially where acid soil conditions cause free iron (Fe)
and aluminum (Al) oxides to bind soil phosphorus (P) into
forms unavailable to plants. Legumes are especially sensitive
to low P availability since biological nitrogen fixation has
a high P requirement. Application of P fertilizer is only
a partial solution since P fertilizers are resource-dependent
and expensive, and subject to the same chemical processes
that immobilize native soil P. Besides phosphorus, nitrogen
could be another important limiting factor for soybean growth
due to the lack of effectively native rhizobial strains in
most tropical and subtropical areas. Application of N fertilizer
not only wastes resources but also causes environmental pollution.
»The approach
Year 2 workplan: 
English
There has been significant progress in genetic improvement
of common beans (Phaseolus vulgaris) and soybeans (Glycine
max) for better adaptation to low soil P. Research at
both Penn State University (PSU) and South China Agricultural
University (SCAU) has demonstrated the central importance
of root morphology (esp. root hair characteristics) and architecture
in conferring P-efficiency in common bean. These root traits
have been used at SCAU to screen for P-efficiency among soybean
landraces and bred lines, as well as create new genotypes
with improved P efficiency and enhanced nitrogen fixing capacity.
The current project represents the second phase of an earlier
CCRP project (2002-2005), which targeted the development of
P-efficient soybean varieties P-deficient soils of South China.
During phase one, collaborators at SCAU and PSU validated
that the same traits that are important for P-efficiency in
common bean are also important in soybean. The team also developed
new P-efficient soybean varieties for the low P soils of South
China, some of which have been commercially released to farmers
in South China. These new genotypes have shown substantial
yield gains in low P soil compared with conventional genotypes,
in some trials doubling yield without additional inputs, thereby
demonstrating the potential of this approach.
During phase two, collaborators from Mozambique have joined
the research team and the project's mandate area have been
expanded to include this southern African country where more
P-efficient soybean and bean varieties could help to improve
the health and well-being of some of the world's most economically
disadvantaged rural communities. Evaluating legume performance
under Mozambique conditions will also be important for looking
more closely at potentially important genotype-by-environment
interactions for P-efficient root traits. For example, shallow-rooted
genotypes are able to acquire more P from the soil since in
most soils P availability is greatest in the topsoil and declines
with depth. However, shallow-rooted genotypes are more sensitive
to drought, which is also an important constraint in many
agroecosystems, especially those in Southern Africa. In such
systems, genotypes with root systems that balance both deep
and shallow soil exploration may be required. This project
are currently evaluating ecological tradeoffs for root architectural
and morphological traits in the specific contexts of South
China and Mozambique.
Phosphorus-efficient soybeans and beans are likely to be extremely
useful in the low fertility soils of South China and Mozambique.
In order to realize the potential of this technology, Phase
2 of the project is focusing on the following activities:
(1) continue the soybean breeding program in China and begin
a bean and/or soybean breeding program in Mozambique with
specific focus on P efficiency, (2) develop a better understanding
of how traits conferring P efficiency in legumes affect crop
responses to other environmental factors, (3) determine how
P efficient legumes will affect agroecosystem productivity
and sustainability, as well as the economic well being of
rural communities, and (4) develop African scientific capacity
in plant nutrition so that this effort can be sustained.
»The goal
The overall goal of the project is to improve food security
and agroecosystems sustainability in tropical-subtropical
regions of China and Africa through increased productivity
of soybean and common bean on low P soils.
»Back to top
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Phosphorus trial in Yingde. The
two rows show the difference between our varieties with
the check variety on a low-P soil. |
Project impact
Grain legumes play a key role in the food security of developing
countries because of their unique importance to human nutrition
and agricultural sustainability. Low soil fertility, particularly
low phosphorus (P) availability, is the primary limiting factor
to legume production in many of the developing countries.
The CCRP project on legume adaptation to marginal soils, led
by Xiaolong Yan at South China Agricultural University, addresses
this problem by breeding and deployment of more P-efficient
soybean and common bean that yield better than conventional
cultivars in low-P soils, thereby improving the health, income,
and productivity of rural communities.
In the first phase of project (2002-2005), the team developed
improved soybean germplasm with superior root characteristics
that enable better adaptation to low-P conditions and more
efficient utilization of applied fertilizers. After an integrated
effort over four years, the team has gained insights into
the physiological, genetic and molecular basis of P efficiency
and the agroecological dimensions of efficient P utilization
in the soybean production system, while at the same time developing
a number of P efficient soybean genotypes that have passed
the Chinese national regional variety trials. These improved
soybeans have been released to farmers in South China. These
new genotypes show substantial yield gains in low P soils
compared with conventional genotypes, indicating a great potential
for future impacts. Continued efforts are being made to realize
the long-term objective of the project in developing new germplasm
and technical innovations that may have great impacts on food
security both in China and other developing nations, particularly
in Africa.
For the second phase of the project (2006-2009), a new partnership
has been formed for an extended effort in increasing P efficiency
and production of grain legumes in China and Africa. In the
new phase, the project team has included partners in Mozambique
while maintaining core activities in South China. The team
continues to breed soybean for P efficiency and other important
agronomic traits with the existing materials that we have
developed and test the newly developed genotypes (varieties)
under various soil/climatic conditions through Chinese National
Field Trials. Cropping systems are being optimized (using
intercropping, rotation, etc) through large-scale experimentation
and farmer participatory research. The project is creating
effective and reliable legume (particularly soybean) processing
facilities that can be used in households of the rural areas.
These research outcomes will not only generate great impacts
in South China but will also serve as the technical reserve
for generating impacts in Africa through training and collaborative
research proposed for the second phase of the project. Project
collaborators in Mozambique have launched a breeding program
for more P efficient common beans and/or soybean, and are
rigorously assessing the biophysical and socioeconomic impacts
of P-efficient legumes on rural communities in Africa.
»Back to top
___________________________
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Dr. Jonathan Lynch, Dr. Hong
Ma, Dr. Leon Kochian and Dr. Xiaolong Yan. |
Investigators
»Partner institutions
»Investigators at SCAU
(*=project leaders)
Dr. Hong Liao
Dr. Hai Nian
Ms. Huixia Cui
»Investigators at IIAM
Mr. Magalhaes Miguel
»Investigators at PSU
Dr. Jonathan Lynch
Dr. Jill Findeis
»Back to top
Annual progress reports
Click the links below for annual progress reports.
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»Original grant
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»First renewal
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»Back to top
Publications
CCRP supported publications
File date: 8/2006
»Back to top
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