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The use of Bt cotton to enhance crop yield
Ijaz Ahmad Rao
Pakistan is an agriculture-based country. So agriculture remains the dominant sector of its economy. Pakistan is the world's fourth largest producer of cotton after China, the USA and India.
Cotton, or white gold as it is aptly called, is grown for its lint and seed. Till the end of August cotton crop was in perfect condition in most part of the country, but in September many types of bollworm like Pink, Spotted and American attacked cotton in the Sindh and Punjab provinces.
The "Lashkari Sundi" Army worm and "American Sundi" heliothis are badly damaging the cotton crop.
Although pressure of pests, especially bollworms, is not a new phenomenon to the crop in the country, at present the use of pesticides is the only way out to keep these bollworms under control, while surprisingly this year pesticides needed to fight bollworms in cotton fields are not working effectively.
So, dismayed over this failure of insecticides the cotton growers started making excessive use of pesticides in terms of higher dose and frequency of spray interval.
But even with 3-4 times higher than recommended use of pesticides the bollworms continue to devastate the cotton crop in different parts of Sindh and Punjab.
According to some farmers in Bahawalpur and Lodhran this is for the first time that pest can be seen crawling in the village streets.
On the one hand excessive use of pesticides has caused shortage of pesticides in the market, on the other it has increased the costs of cotton production apart from the negative impact on the environment and human health.
Currently market is surrounded by different speculations and rumours like the quality and quantity of pesticides available.
Farmers are blaming the government bodies, pesticide traders and others for not taking steps promptly in such circumstances.
The growers want to know why the pesticides are not controlling bollworms as it used to do? How they can confront with such a challenge in future?
The fact is that it is natural that under regular exposure to insecticides, the insects are likely to develop resistance to insecticides rendering even these poisons ineffective.
So this is the time when tools of biotechnology can help us overcome such a catastrophe caused by different pests, which are injurious economically to all of our industries.
Role of Biotechnology: Biotechnology existed long before such a terminology was coined. But in modern times, the word "biotechnology" has become a household word because of its application in the fields of agriculture, health, environment and industries.
In the agriculture biotechnology for many years, scientists have used traditional plant-breeding techniques to develop improved plant varieties with higher yields and greater resistance to pests, diseases and environmental stresses.
However, traditional plant-breeding techniques can be time-consuming. Sometimes it may take up-to 15 years or more before a new plant variety reaches the market.
Biotechnology or genetic engineering enables scientists to breach the reproductive barriers between species.
Through the use of genetic engineering techniques, genes from one plant, animal, or micro-organism can be incorporated into an unrelated species, thus increasing the range of traits available for developing new plants.
So the question is what is Bt cotton? And how it will prevent our crops from the attack of different pests?
Bt Cotton is not a variety, but a type of cotton, which carries a special gene derived from soil born bacterium "Baccillus thuringiensis". Such a gene can be added to any other crop like maize, rice wheat or rather any living organism through the technology of genetic engineering to produce the so-called GMO's "genetically modified organisms" or transgenics.
Bt gene in such cotton type produces a special type of protein called cry protein.
When an insect feeds on Bt cotton the cry protein is ingested and causes death of the insect.
The most important property of this protein is that it only kills group lepidopteron insects and particularly cotton bollworms, while other insect species, including beneficial insects, wild life, marine life are not affected.
Moreover, the insecticidal protein in the plant begins to break down immediately after the plant dies so there is no danger of its toxic effect in soil or underground water.
The Bt cotton has thus in-plant system of protection against bollworms without any harmful effect on other insects or living organisms.
Current Status of Bt Cotton in the world The work on transgenic cotton was started in the USA during 1990s first to develop herbicide resistant and then bollworm-resistant cotton.
A multinational company Monsanto commercialised the first Bt cotton in the USA in 1996. Since then it has been adopted in Mexico, Australia, China, Argentina, Indonesia, India, Egypt and South Africa.
At present Bt cotton covers over 70 percent of area under cotton in the USA and 40 percent in South Africa and its share is increasing in China and India.
The world-wide acreage devoted to Bt crops has grown steadily from only about 5 million acres in 1996 to nearly 200 million acres in 2003.
This trend is likely to continue with increased planting of transgenic crops in China, India and several other countries. The total market for transgenic seed now exceeds $3 billion.
Pakistan faces too many challenges and problems to be denied the wonderful tool of biotechnology. Agricultural biotechnology holds a great promise for Pakistan. Tissue culture and marker-assisted selection are already in widespread use across the country.
In Pakistan government research began on genetic engineering (GE) cotton in the mid 1990s by the National Institute for Biotechnology and Genetic Engineering (NIBGE) after pests caused extensive damage to the bumper cotton crop.
Government scientists said that at the laboratory level, Pakistan has developed Bt cotton, GE sugarcane, Bt soybean, Bt rice and Bt tomatoes, but these cannot be used in the absence of bio-safety laws.
Dr Kauser Abdullah Malik, Member (Bio-Sciences), Pakistan Atomic Energy Commission (PAEC), said while addressing the "World Cotton Bio-tech Moot" held at International Centre for Biosaline agriculture, Dubai, on 9th October 03, that PAEC has developed genetically engineered virus resistant cotton variety against Cotton Leaf Curl Virus "CLCV", (which caused heavy losses to cotton crop in 1991-92) at NIBGE.
It is wroth noting that in view of the above claims by our scientists quantification and evaluation of these Bt or GE crop varieties cannot be ascertained unless these GE varieties are released and tested in the field.
Pakistan is produced 10.50 million cotton bales in 2003-04 in the area sown on 6.50 million acres as compared to 4.95 million acres in 2002-03.
The expected yield is 8 million bales from Punjab, while 2.4 million bales from Sindh and the rest from Balochistan and NWFP.
But according to some growers due to the severe attack of bollworms, cotton yield may decline by 20 to 40 per cent in Sindh and Punjab.
However, the effects of bollworms attack will start reflecting in the face of cotton "phutti" arrival between the month of November and December because the menace may have damaged the cotton bolls, which grew after September, affecting the second and third pick of cotton.
It is notable that each year, the non-Bt cotton has to be sprayed every week just to keep the bollworms out.
Therefore, Pakistan has to import pesticides worth around $90 million per year while the entire pesticides market hovers between Rs11 and Rs14 billion. With Bt cotton, however, farmers can reduce the number of applications by two or three a season.
Because Bt Cotton or transgenic crops with in-built resistance to insect pests and diseases can be extremely useful as this would result in the reduction of insecticide use apart from making pest management simple for the farmer.
Introduction of the boll worm resistant transgenic cotton is expected to reduce the use of chemicals used to control bollworm, specially Helicoverpa, importantly at a time when resistance to most insecticides, including pyrethrolids, is on the increase all over the world.
On the one hand genetic engineering promises benefit to the society, on the other it has raised some ethical, social, environmental and trade issues, among certain nations.
A significant socio-economic issue that can arise from the introduction of transgenics into the Pakistani farming system is that high priced seeds may benefit the prosperous and large farmers, thus providing a negative externality on small and marginal farmers.
On the other hand it can also be argued that the developments from the application of biotechnology would be beneficial to low input farming practices wherein the cost of chemical inputs can be minimised.
It is now only a matter of time before we experience the full social, economic and environmental impact of transgenics in our country.
However, an effective and appropriate regulatory system is required like bio-safety guidelines, which will set up legal requirements for import, export, development and release of Bt cotton and other GE crops into our environment.
Therefore through activating Bio-Safety regulations as soon as possible either by adopting American model or European regulations our farmers can enjoy the benefits offered by biotechnology.
Plant biotechnology is helping today to provide people with more and better food by controlling pest attack on the crops.
It holds even greater promise for the future. Whether cotton farmers in China, India and South Africa, canola farmers in Canada, soybean farmers in Argentina or corn farmers in Spain and the United States, millions of farmers around the world are using biotech seeds to boost yields, improve their livelihoods and preserve the environment.
Having considered all of the technologies known to us today, and various arguments of the anti-biotechnology lobby, I remain more convinced than ever that plant biotechnology is still the best hope not only for meeting the food needs of the ever-growing human population, but also for conserving our precious but dwindling land and water resources and preventing or even reversing environmental degradation.
Pressure of pests, especially of bollworms, is not a new phenomenon to the crop in the country, most of cotton growers remembered that in 1991-92 after picking an all-time bumper crop of 12 million bales, the cotton crop had to confront with the challenge of cotton leaf curl virus (CLCV).
Although this year we expected a bumper crop, the menace of pest infestation, especially of American, Army and Spotted bollworms, coupled with shortage of pesticides, has created doubts even about achieving the official cotton production target of 10.50 million bales.
In short despite the controversy on GMO, Pakistani scientists have long held that Bt cotton varieties will ensure American, Army and Spotted bollworms free crop that would result in low costs for farmers and greater predictability in export earnings.
Clearly, Pakistan has a great deal to gain economically from moving down the GM path if there are no environmental externalities and no adverse consumer reactions. Bt cotton, Bt Rice and Bt maize will contribute to Pakistani economic welfare in billions each year.
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Pakissan.com;
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