Applications of Biotechnology in Agriculture

Growing of crops for food has been done since the beginning of mankind the processes to achieve this only changed over the centuries, the advent of technology brought new and improved ways to produce crops giving rise to agriculture which has enabled development of civilisation. Agriculture evolved through different historic periods, it went through the prehistoric, Roman feudal and where we are now, the scientific period applying several technologies to achieve its aims. Activities went from domestication of crops, use of metal tools, trading of food products, selecting traits like pest control through animal (conventional) breeding, mutation breeding, green revolution and presently genetically modified crops (GMOs).

Agriculture is the process of utilising land for producing crops, rearing animals also referred to as farming with practices like mulching, flooding, fallowing, crop rotation and multiple cropping. As the world population grows the need for more food puts an increase in its production and agricultural land resources making comments made by Robert Malthus ‘ Human population will over strip food production ‘ a reality. The change in climate contributes to loss of land due to rising sea levels, use of harmful pesticide to control pest adds severe contaminants to the environment from the use of organophosphorous compounds to DDT (Gatehouse, A. M. R., 2010) allowed the market of agriculture to seek alternative measures which are less harmful, cheap, sustainable and environment friendly.

Biotechnology as defined by The Convention on Biological Diversity. Article 2. UNEP 1992 is ‘Any technological application that uses biological systems, living organisms, or derivatives, to make or modify products or processes for specific use’. Biotechnological principles have been applied to industrial processes, food production and husbandry. It began with ‘zymotechnology’ used to describe the application of fermentation in wine brewing, leather curing, extraction of cream from milk and making of citric acid (Robert Bud, 1994). This developed over the years from using bacteria and yeast for making foods like bread, yogurt and producing drugs like penicillin. These applications resulted to the birth of Genetic Engineering in the search for greater crop productivity, improved yield, cures to diseases and enhanced animal growth which involves the process of manipulating DNA in living organisms creating a ‘transgenic’ organism. Advances in the twentieth century were based on the application of Mendelian genetics and principles (Ruttan, 1999) taking into account physiological traits while the twenty first century is based on biotechnology and its applications such as Bacillus thuringiensis (Bt) crops, and herbicide resistant crops.

This essay discusses the contributions of biotechnology in the world today, the past and present applications as regards to agriculture. It gives the general view of its applications high lightening the advantages (benefits) and disadvantages (risks) of this technology in agriculture and mentions the future trends of the technology.

BIOTECHNOLOGY AS A SCIENCE

Traditional agricultural practices of cross breeding different crop variety to develop a desired trait like disease resistance is an example of the application of biotechnology in agriculture, this had been practiced since 1970s and shows biotechnology has been around for a while. Biotechnology as a science is applied in modern day agriculture which has coined the word ‘agricultural biotechnology’ also referred to as ‘green biotechnology’. It presently entails processes in genetic engineering and molecular biology to create new food, produce transgenic plant and animals and involves applications in agricultural practices like developing biofertilizers, pest resistant crops, herbicide tolerant plants and selection in animal breeding. The connection of this field lies in the interaction between food processing techniques and living systems for food and animal agriculture such as production of vaccines to address pest, disease and viruses.

Genetic engineering enables the isolation and characterisation of genes to understand and produce proteins which gives primary clues to altering the genetic make up of the organism to produce the desired benefit or produce new genes which enable food and improved animal production which is the ultimate aim of agriculture. It uses molecular markers to characterise genetic diversity to select breeding type and ensure intra-specific variation (Dawson et al, 2009).

The Need

Conventional breeding brought about uncontrolled crosses and results as the genetics of the crossing was not fully understood or predicted, an example of this is the production of desirable traits with unwanted ones such as pest resistance with poor quality (Wieczorek, 2003). It was labour intensive and time consuming which sparked a need for a more productive and effective approach. This is answered by current applications of agricultural biotechnology as genetic engineering allow for proper and specific characteristics to be attributed to the transgenic organism.

The constraints on crop productivity by biotic stress such as pest, insect and pathogens like corn ear worm and by abiotic stress like drought, frost brought about research to produce solutions like pest resistant maize and drought tolerant crops. Genetically engineered crops are answering these constraint allowing herbicide tolerance, insect, virus resistance to be conferred on crops.

Also there is an economic need for effective and less harmful insecticide as farmers require a cheaper way to protect crops in the field and engage in sustainable methods of practicing agriculture.

Applications and Contributions of Biotechnology to Agriculture

Biotechnology has contributed to plant and animal productivity, the manipulation of genes in plant and animals has conferred protection against stress, pest, diseases and insects. This has created opportunities and benefits for both farmers and the economy to improve crop yield indirectly by the reduction of these factors and to produce more sustainable methods and food products. As the genes that confer these traits are from naturally occurring organisms using their insecticidal properties they use for survival (Carlini et al, 2002) such as the Cry proteins of Bt used in cotton.

In Plants

The commercialisation of Bacillus thuringiensis (Bt) crops in countries like United States, India and Australia is a huge benefit to both farmers and the economy as this has enables the control of insect pest and improved crop yield by reducing pest. For example Bt cotton used in India for bollworm control is leading to increased production and reduced costs (Barwale, et al 2004). The toxins exert pathological effect by forming lytic pores in cell memebrane of insect gut (Maagd, et al, 2001).

Herbicide resistance trait in plant like in the case of glyphosate resistant soybeans used for weed control allows farmers kill yield reducing weeds, confer greater safety to multiple glyphosate application (Green, J., 2009) and maximise crop productivity. Varieties have been developed since its first introduction in 1993 (Carpenter, 1999). This application allows broad spectrum of herbicide with environmental benefit to be used without affecting the plant as the gene produces a glyphosate-tolerant form of EPSPS which is needed for amino acid synthesis and is blocked by glyphosate in non transgenic plants. (ISSSA, 2006).

In Animals

In animals, biotechnology has contributed to agriculture by the genetic improvement of livestock without crossbreeding (Wheeler, 2007) such as the production of trangenic animals with improved growth rate, quantity and quality of meat and milk. An example is the use of Bovine Somatotropin (bST ) in cows to enable changes in animal body tissue to allow more nutrients in their metabolism to be used in milk synthesis (Bauman, 1992). However applications in disease control of animals, vaccines for disease resistance such as tick vaccines, transgenic salmon for enhanced growth using sockeye salmon growth hormone gene (Devlin et al, 1994 and 1995) are all potentials of the technology in agriculture with some level of commercialisation in some part of the world with regulatory approval pending in others.

BENEFITS

Increase in crop protection: Agricultural biotechnology has improved crop protection by enabling the use of fewer pesticides creating a sustainable way to practice agriculture and protect land as a natural resource. The built-in protection for crop plant against insects and their diseases has significantly reduced the need to use conventional insecticides which have broad spectrum with no specificity. It in turn reduces environmental contamination and the risk it confers to humans. For example the approval and commercialisation of Bacillus thuringiensis (Bt) crops like cotton, canola and maize proves the enormous advantage GMO crops can do for the world. The toxins used are specific, beneficial insects are not affected and chances of evolutional resistance building are significantly low.

Increased Food Production and quality: The effective controls of pest, insects and weeds have produced an indirect effect on the increase of yields with added unexpected benefits such as reduction of specific fungal mycotoxin in Bt Zea mays (maize) (Shelton et al, 2002). It has created variety in food we find in the market today.

Economic Benefit to Farmers: Farmers are able to make more profit with cheaper methods of pest control. The use of Bt crops will positively affect the livelihood of small farmers by improving their net incomes (Barwale, et al 2004) decreasing the cost of purchasing chemical, as they are getting biological control in the transgenic seeds used for farming.

Improved Nutrition: The improvement of food quality by genetically modified crops has an added benefit of improving nutrition. For the developing world where the main diet is rice the production of ‘golden rice’ with beta carotene to meet the required vitamin A requirement is a benefit towards reducing vitamin A deficiency in children.

Sustainable, safe and clean: GMO crops are the most scrutinised and regulated crops rendering them safe. Applications are clean and neat proving to be more sustainable for our resources. Bt genes are available and proven safe as a bio-pesticide and allows the exploitation of plant biotechnology for agricultural biotechnology.

Efficient use of farmland: The improvement of crops by agricultural biotechnology creates the advantage of utilising less land for farming which in turn reduces erosion (Mannion, A. M., 1995) and helps with biodiversity in the ecosystem.

RISKS

Evolution of Resistance: There is the potential for transgenic crops to develop evolutional resistance (Zhao et al, 2003) and studies carried out by Zhao et al (2003), Gould, F., (1998), Roush, R. T., (1998) show ways such as use of different toxins in different varieties and pyramiding to delay this effect. Also there is the risk in the use of markers genes conferring antibiotic resistance from bacteria vectors to plant which can be addressed by use of natural markers and techniques like florescent markers from jelly fish. The potential of weeds becoming resistant specific herbicide due to constant exposure creating the ‘super weed’.

Undesirable and unintended effects: Just like in conventional cross breeding in plants and animals there is the risk of getting an undesirable or unintended effect in the use of agricultural biotechnology.

CONCLUSION

Biotechnology is a tool for advancement in agricultural practices with important and beneficial applications. It is enabling global solutions to the problems created by human population. Like any other technology it should be checked for risks without downplaying or overlooking its potential and benefits as a result of lack of understanding or the scare of the unknown. Furture trends in agricultural biotechnology are promising with research and studies performed frequently to address its disadvantages and enable global commercialisation and application of this technology.