Emerging opportunity in agri biotechnology : Hemang Baxi and Dr. Pranjivan Zaveri

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

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	Swain and Abhijita, 2013
GS1  tobacco	enhanced grain yield and biomass as well as improved nitrogen content in wheat, tobacco and maize	Oliveira et al., 2002
AS1 Arabidopsis	improved soluble seed protein content, total protein content, and better growth in nitrogen-limiting medium	Lam et al., 2003
Dof1  maize	improved growth under nitrogen limiting conditions as well as enhanced nitrogen assimilation	Yanagisawa, 2000
OsNADH-GOGAT1 rice	increase in spikelet weight of up to 80% in rice	Yamaya et al., 2002
AlaAT  barley	production and degradation of alanine (functions as an intercellular nitrogen and carbon shuttle) in rice	Shrawat et al., 2008
STP13 Arabidopsis	improved plant growth and nitrogen use	Schofield et al., 2009

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. 

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.

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.

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%.

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. 

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. 

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)