 |
| H C Baxi Consultant, Agri Biotech Gujarat |
Emerging opportunity in agri biotechnology
The
biotech research and development toward genetic resistance to bollworm insect
in the form of Bt cotton is regarded as a milestone to have an impact in
raising the world production of this fibre crop besides reduction in use of
deadly insecticides to the extent of 45–50%. It was done by transferring Cry Ac
genes encoding the toxic crystal δ - endo toxin protein from the soil bacterium
Bacillus thuringiensis for the first time by Monsanto of USA, which has
the ability to control the bollworms during crop growth effectively. Use of
this technology is also helpful in improving wild life population, reduced
run-off of insecticides, reduced air pollution and improved safety to farm
workers and neighbourhood. Much has been done to improve cotton as GMO by way
of inserting many genes targeting insects. The efforts are underway all across
the world to tape newer sources of resistance and other traits in several crops.
The agriculture biotech facts in 2013:
The Year
2013
is the 18th year of commercialization of biotech crops worldwide. Its
commercialization confirmed the promise of biotech crops to deliver substantial
agronomic, environmental, economics, health and social benefits to large- and small-scale
farmers worldwide. The growth of biotech crops was from 1.7 million hectares in
1996 to 175.1 million hectares in 2013.
In the last 18 years, millions of farmers in ~30 countries worldwide have
made more than 100 million independent decisions to plant an accumulated
hectarage of 1.6 billion hectares of biotech crops.
Of
the 27 countries that planted biotech crops in 2013, nineteen were developing
and eight were industrial countries. The five lead developing countries in
Latin America (Brazil, Argentina), Asia (India, China) and Africa (South Africa) grew 47% of global
biotech crops.
Brazil
is top among countries in 2013 to plant 40.3 million hectares of three biotech
crops. Around 7.5 million farmers in China and 7.3 million farmers in India
grew 15.2 million hectares of Bt cotton during 2013.
The top biotech crops in order of hectare are soybean, maize, cotton and
canola, alfalfa, sugar beet, papaya, squash, poplar, tomato and sweet pepper in
2013.
Developing
countries planted eight biotech crops in 2013 with accumulated hectarage of
91.1 million hectares. Bangladesh is the first country to grow GMO brinjal
(eggplant).
Farmers
from Latin America, Asia and Africa collectively grew 94.1 million hectares (
54% of the global 175.2 million hectares) of biotech crops in 2013, compared
with industrial countries at 81.1 million hectares ( 46% of the global total).
The top five countries planting biotech crops are USA, Brazil, Argentina,
India and Canada. The USA continued to be the lead producer of biotech
crops globally with 70.1 million hectares, and average adoption rate of 90%
across all biotech crops. Biotech Canola had high adoption rate of 96% in 2013
in Canada.
In Africa, Burkina Faso and Sudan continued to make progress in increasing
their Bt cotton hectarage in 2013, whereas South Africa maintained at 2.9
million hectares.
Five countries in the European Union planted 148,013 hectares of biotech
maize in 2013. The countries are Spain (with high adoption rate of 31%), Portugal,
Czech Republic, Romania and Slovakia.
Biotech crops helped 16.5 million farmers and their families in 2013
worldwide.
Biotech crops contribute to food security, sustainability and climate
change. From
1996 to 2012, economic gains at the farm level of US$116.0 billion were
generated globally by biotech crops, owing to reduced production costs and
substantial yield gains. Biotech crops
have reduced the amount of pesticides used by 497 million kilograms. In 2012
alone, fewer insecticides spray reduced CO2 emissions by 26.7 billion
kilograms, equivalent to taking 11.8 million cars off the road for a year.
The outlooks for biotech crops in the second decade of commercialization
looks encouraging. These crops have the potential to make a
substantial contribution to cutting poverty in half and optimizing crop
productivity. Biotech crops can serve as engine of rural economic growth for
the alleviation of poverty for the world’s small and resource-poor farmers.
Emerging technology requiring attention in
biotechnology:
Climate change and
its effect in agriculture
The continuing
increase in greenhouse gas emissions raises the temperature of the earth’s
atmosphere. This results to melting of glaciers, unpredictable rainfall
patterns and extreme weather events. The accelerating pace of climate change,
combined with global population and depletion of agricultural resources
threatens food security globally.
The over-all
impact of climate change as it affects agriculture was described by the
Intergovernmental Panel on Climate Change (IPCC, 2007), and cited by the US EPA
(2011) to be as follows:
- Increases in average
temperature will result to: i)
increased crop productivity in high latitude temperate regions due
to the lengthening of the growing season; ii) reduced crop
productivity in low latitude subtropical and tropical regions where summer
heat is already limiting productivity; and iii) reduced productivity due
to an increase in soil evaporation rates.
- Change in amount of
rainfall and patterns will affect soil erosion rates and soil
moisture, which are important for crop yields. Precipitation will increase
in high latitudes and decrease in most subtropical low latitude regions—some
by as much as about 20%, leading to long drought spells.
- Rising atmospheric
concentrations of CO2 will boost and enhance the growth of some
crops but other aspects of climate change (e.g. higher temperatures and
precipitation changes) may offset any beneficial boosting effect of higher
CO2 levels.
- Pollution levels of troposphere
ozone (or bad ozone that can damage living tissue and break down
certain materials) may increase due to the rise in CO2 emissions.
This may lead to higher temperatures that will offset the increased growth
of crops resulting from higher levels of CO2.
- Changes in the frequency
and severity of heat waves, drought, floods and hurricanes remain a key uncertain factor that may
potentially affect agriculture.
- Climatic changes will
affect agricultural systems and may lead to emergence of new pests and
diseases.
Contribution of biotech
crops in mitigating effects of climate change:
Green
biotechnology offers a solution to decrease green house gases and therefore
mitigates climate change. Biotech crops for the last 16 years of
commercialization have been contributing to the reduction of CO2 emissions.
They allow farmers to use less and environmentally friendly energy and
fertilizer, and practice soil carbon sequestration.
- Herbicide-tolerant
biotech crops such as soybean and canola facilitate zero or no-till, which
significantly reduces the loss of soil carbon (carbon sequestration) and
CO2 emissions, reduce fuel use and significantly reduce
soil erosion.
- Insect resistant biotech
crops require fewer pesticide sprays that results in savings of
tractor/fossil fuel and thus less CO2 emissions. For 2011,
there was a reduction of 37 million kg of active ingredients, decreased
rate of herbicide and insecticide sprays and ploughing reduced CO2 emission
by 23.1 billion kg of CO2 or removing 10.2 million
cars off the road.3
Biotech crops adapted to climate
change
Crops can be
modified faster through biotechnology than conventional crops, thus hastening
implementation of strategies to meet rapid and severe climatic changes. Pest
and disease-resistant biotech crops have continuously developed as new pests
and diseases emerge with changes in climate. Resistant varieties will also
reduce pesticide application and hence CO2 emission.
Crops tolerant to various abiotech stresses have been developed in
response to climatic changes.
Salinity-tolerant crops
Biotech salt-tolerant crops
have been developed and some are in the final field trials before
commercialization. In Australia, field trials of 1,161 lines of genetically
modified (GM) wheat and 1,179 lines of GM barley modified to contain one
of 35 genes obtained from wheat, barley, maize, thale cress, moss or yeasts are
in progress since 2010 and will run till 2015. Some of the genes are expected
to enhance tolerance to a range of abiotic stresses including drought, cold,
salt and low phosphorous. Sugarcane that contains transcription factor
(OsDREB1A) is also under field trial from 2009 to 2015.
More than a
dozen of other genes influencing salt tolerance have been found in various
plants. Some of these candidate genes may prove feasible in developing salt
tolerance in sugarcane, rice, barley, wheat, tomato and soybean.
Drought-resistant
crops
Transgenic
plants carrying genes for water-stress management have been developed.
Structural genes (key enzymes for osmolyte biosynthesis, such as proline,
glycine/betaine, mannitol and trehalose, redox proteins and detoxifying
enzymes, stress-induced LEA proteins) and regulatory genes, including
dehydration–responsive, element-binding (DREB) factors, zinc finger proteins,
and NAC transcription factor genes, are being used. Transgenic crops carrying
different drought tolerant genes are being developed in rice, wheat, maize,
sugarcane, tobacco, arabidopsis, groundnut, tomato, potato and papaya.
An important
initiative for Africa is the Water Efficient Maize for Africa (WEMA) project of
the Kenyan-based African Agricultural Technology Foundation (AATF) and funded
by the Bill and Melinda Gates Foundation (BMGF) and Howard G. Buffet
Foundations. Drought tolerant WEMA varieties developed through marker assisted
breeding could be available to farmers within the next 2 or 3 years.
Drought-tolerant and insect-protected varieties developed using both advanced
breeding and transgenic approaches could be available to farmers in the later
part of the decade. In 2012, a genetically modified drought tolerant maize
MON 87460 that expresses cold shock protein B has been approved in the US for
release in the market.
Biotech crops for
cold tolerance
By using genetic
and molecular approaches, a number of relevant genes have been identified and
new information continually emerges. Among which are the genes controlling
the CBF cold-responsive pathway and together with DREB1 genes,
integrate several components of the cold acclimation response to tolerance low
temperatures.
Cold tolerant GM
crops are being developed such as GM eucalypti, which is currently being field
tested in the US by Arborgen LLC since 2010. Thale cress has been improved to
contain e DaIRIP4 from Deschapsia antarctica, a
hairgrass that thrives in frosts down to -30C, and sugarcane are being
introgressed with genes from cold tolerant wild varieties.
Biotech crops for heat stress
Biotech crops for heat stress
Expression of
heat shock proteins (HSPs) has been associated with recovery of plants under
heat stress and sometimes, even during drought. HSPs bind and stabilize
proteins that have become denatured during stress conditions, and provide
protection to prevent protein aggregation. In GM chrysanthemum containing
the DREBIA gene from Arabidopsis thaliana, the
transgene and other heat responsive genes such as the HSP70 (heat shock
proteins) were highly expressed when exposed to heat treatment. The transgenic
plants maintained higher photosynthetic capacity and elevated levels of
photosynthesis-related enzymes.
Forward looking for biotech in
climate change
Improved crops
resilient to extreme environments caused by climate change are expected
in a few years to a decade. Hence, food production during this era
should be given another boost to sustain food supply for the doubling
population. Biotech research to mitigate global warming should also be
initiated to sustain the utilization of new products. Among these are: the induction
of nodular structures on the roots of non-leguminous cereal crops to fix
nitrogen. This will reduce farmers’ reliance on inorganic fertilizers. Another
is the utilization of excess CO2 in the air by staple crop rice
by converting its CO2 harnessing capability from C3 to C4
pathway. C4 plants like maize can efficiently assimilate and convert CO2 to
carbon products during photosynthesis.
Genetic
engineering for nitrogen use efficiency (NUE):
Nitrogen is one of primary macronutrients that plants need for
survival, aside from phosphorus and potassium. It is important for plant growth
and development, particularly in metabolic processes such as production of
nucleic acids, proteins and other helper molecules. It is a basic component of
plant’s green pigment known as chlorophyll, which is vital for photosynthesis.
Nitrogen is abundant in the atmosphere but is not readily available
for plants. It can be used up by plants when it is converted into ammonia from
fixation by bacteria to make nitrogen-containing molecules.
Biological nitrogen fixation occurs in some plants through
metabolic activities of free-living or symbiotic bacteria. One common symbiotic
bacterium involved in nitrogen fixation is known as Rhizobium which
attacks and reproduces in the legume plants' roots to get their nutrition.
After about a week of infection, white or grey nodules form in the roots. The
bacteria through the action of the enzyme nitrogenase, convert the nitrogen gas
(N2) into ammonia (NH3).
Since the discovery of nitrogen fertilizer, use of synthetic
nitrogen has increased dramatically leading to significant boost in crop
yields. However, only 30–50% of the applied nitrogen is absorbed by the plants
and the wasted nitrogen cause considerable impacts on the environment. It can
contribute to algal bloom and hypoxia (reduced oxygen in water) leading to
significant loss of aquatic life and diversity and contribute to depletion of
the ozone and global warming. Thus, scientists seek for more
environment-friendly and cost-effective strategies to improve nitrogen use
efficiency of crops. One of these strategies is to use genetic engineering.
Improving the nitrogen use efficiency of plants requires
manipulation of several genes involved in nitrogen uptake, translocation and
remobilization; carbon metabolism; signalling targets; and regulatory elements.
Several genes (Table 1) from different sources have been found to control these
processes and were investigated if the manipulation of the genes can lead to
improved nitrogen use of plants.
Table
1. Genes studied for improvement of nitrogen use
Gene(s) and source
|
Result(s)
|
Reference
|
nif genes
Klebsiella pneumoniae |
activated nitrogenase
function in Escherichia coli
|
|
GS1
tobacco |
enhanced grain yield
and biomass as well as improved nitrogen content in wheat, tobacco and maize
|
|
AS1
Arabidopsis |
improved soluble seed
protein content, total protein content, and better growth in
nitrogen-limiting medium
|
|
Dof1
maize |
improved growth under
nitrogen limiting conditions as well as enhanced nitrogen assimilation
|
|
OsNADH-GOGAT1
rice |
increase in spikelet weight of up to 80% in rice
|
|
AlaAT
barley |
production and
degradation of alanine (functions as an intercellular nitrogen and carbon
shuttle) in rice
|
|
STP13
Arabidopsis |
improved plant growth
and nitrogen use
|
Status of NUE crops
Corn
One of the crops under study for improvement of nitrogen use efficiency is corn, an important global food crop that requires intensive amount of nitrogen fertilizer. However, like most crops, corn only absorbs a small amount of the nitrogen that is applied to it, leading to economic problems to growers. In 2008, DuPont and Arcadia Biosciences announced that they have completed five years of multiple field trials of corn which resulted to improved nitrogen use efficiency and thus can lead to improvement in farm economics as well as environmentally positive effects.
One of the crops under study for improvement of nitrogen use efficiency is corn, an important global food crop that requires intensive amount of nitrogen fertilizer. However, like most crops, corn only absorbs a small amount of the nitrogen that is applied to it, leading to economic problems to growers. In 2008, DuPont and Arcadia Biosciences announced that they have completed five years of multiple field trials of corn which resulted to improved nitrogen use efficiency and thus can lead to improvement in farm economics as well as environmentally positive effects.
Wheat
In 2012, Australian Centre for Plant Functional Genomics (ACPFG) and Commonwealth Scientific and Industrial Research Organisation (CSIRO) announced their collaboration with Vilmorin & Cie in developing nitrogen use efficient wheat with the aim of reducing nitrogen fertilizer use in Australia. Developing NUE wheat will significantly impact 35% of the world population where wheat is a staple crop and represents 20% of the total protein intake.
In 2012, Australian Centre for Plant Functional Genomics (ACPFG) and Commonwealth Scientific and Industrial Research Organisation (CSIRO) announced their collaboration with Vilmorin & Cie in developing nitrogen use efficient wheat with the aim of reducing nitrogen fertilizer use in Australia. Developing NUE wheat will significantly impact 35% of the world population where wheat is a staple crop and represents 20% of the total protein intake.
CSIRO has applied for a licence for dealings involving 17 wheat
lines and 10 line of barley, which have been genetically modified for improved
nutrient utilization efficiency on a limited scale and under controlled
conditions.
Rice
Rice is the second largest crop and a staple for more than half of the global population. Arcadia Biosciences, African Agricultural Technology Foundation (AATF) and the International Center for Tropical Agriculture (CIAT) reported that in 2013, two years of field trials of nitrogen use efficient rice was completed in Colombia. The researchers integrated the nitrogen use efficiency technology with New Rice for Africa (NERICA) varieties developed by Africa Rice Center. Results of the trials showed that with an application of 50% of usual amount, the transgenic rice lines out-yielded the conventional NERICA variety by 22% on the first year of trial and 30% by the following year.
Rice is the second largest crop and a staple for more than half of the global population. Arcadia Biosciences, African Agricultural Technology Foundation (AATF) and the International Center for Tropical Agriculture (CIAT) reported that in 2013, two years of field trials of nitrogen use efficient rice was completed in Colombia. The researchers integrated the nitrogen use efficiency technology with New Rice for Africa (NERICA) varieties developed by Africa Rice Center. Results of the trials showed that with an application of 50% of usual amount, the transgenic rice lines out-yielded the conventional NERICA variety by 22% on the first year of trial and 30% by the following year.
Canola
Canola is one of the world's most important oilseed crops. The seeds contain 44% oil, which is more than double the oil content of soybeans. Canola oil has heart-healthy characteristics and can also be used as biodiesel because of its exceptional cold weather performance. As of 2007, Arcadia Biosciences have completed five seasons of field trials of canola. The results of the trials showed that the canola plants had the same yield as the conventional varieties, but only half of the required nitrogen input was used. When the same amount of nitrogen with the conventional plants was used, the yield increased by about 15%.
Canola is one of the world's most important oilseed crops. The seeds contain 44% oil, which is more than double the oil content of soybeans. Canola oil has heart-healthy characteristics and can also be used as biodiesel because of its exceptional cold weather performance. As of 2007, Arcadia Biosciences have completed five seasons of field trials of canola. The results of the trials showed that the canola plants had the same yield as the conventional varieties, but only half of the required nitrogen input was used. When the same amount of nitrogen with the conventional plants was used, the yield increased by about 15%.
Sugarbeet
SES VanderHave and Arcadia Biosciences have conducted three years of field trials to assess the yield performance of NUE sugar beet varieties. Results show that the experimental varieties produce higher yields than controls under various fertilizer applications over multiple years. They are now preparing regulatory data which will become available for all NUE technology licensees.
SES VanderHave and Arcadia Biosciences have conducted three years of field trials to assess the yield performance of NUE sugar beet varieties. Results show that the experimental varieties produce higher yields than controls under various fertilizer applications over multiple years. They are now preparing regulatory data which will become available for all NUE technology licensees.
Sugarcane
Sugarcane is cultivated to 25 million hectares worldwide, making it the world's largest sugar crop. Nitrogen fertilizer is an important factor in increasing the yields of sugarcane. South African Sugarcane Research Institute and Arcadia Biosciences announced in 2011 their collaboration in producing high-yielding sugarcane varieties that requires half the amount of the nitrogen fertilizer needed by conventional sugarcane varieties.
Sugarcane is cultivated to 25 million hectares worldwide, making it the world's largest sugar crop. Nitrogen fertilizer is an important factor in increasing the yields of sugarcane. South African Sugarcane Research Institute and Arcadia Biosciences announced in 2011 their collaboration in producing high-yielding sugarcane varieties that requires half the amount of the nitrogen fertilizer needed by conventional sugarcane varieties.
Future
Outlook on Nitrogen Use
A long-term tracer study revealed that 30 years after
application of nitrogen fertilizer to agricultural soils in 1982, around 12–15%
of the fertilizer-derived nitrogen was still residing in the soil organic
matter, while 8–12% of the fertilizer had already leaked toward the
groundwater. Part of the remaining nitrogen fertilizer present in the soil is
predicted to continue to be taken up by crops and to leak toward the
groundwater in the form of nitrate for at least another 50 years, much longer
than previously perceived. The 13% with the development of nitrogen use
efficient crops, environmental concerns such as what the study found out would
be dispelled or at least reduced. At the same time, farmers would lessen
economic losses for nitrogen fertilizer, and use their resources for other farm
inputs or even more crop seeds to get more harvest.
References:
Clive James (2013) “Global Status of
Commercialized Biotech/GM Crops: 2013”.
http://www.isaaa.org/.
(References are being complied and will be added later)
Authors
Hemang Baxi
Agriculture
Business Consultant. Working since last 24 years with Indian Agriculture input
Industry. Working experience with DOW-Nocil, Plant Genes, Vikram Seed Ltd.,
(Now take up by Mahyco Group of Bombay).
Dr. Pranjivan Zaveri
CEO
of Biogene Agritech, a company developing premium quality seeds.
Secretary
of GSPA (Gujarat State Seed Producer Association)
