INTRODUCTION
For many years farmers have been trying to improve their crops, through the selection of desirable characters from the crops at the field. This system of selection from the best or desirable characters is the same principle that plant breeders also do. The cross breeding was the first method and it is still the most widely used technique of crops improvement. As the world population is increasing the demand of food is also increasing. Due to this problem, scientists have developed another method of crops improvement by isolating the desirable genes from the crops or any other organism which to be transferred in to the plant in order to improve the quality and yield of their desirable crop.
This isolation and transfer of genes that scientists (Biotechnologiest) do, is what referred as Genetic Modification (GM) is a technology that used to change the genetic information (genome) of plants, animals or bacteria which it gene is altered to exhibit trait that are not naturally theirs.
GENETIC MODIFIED CROPS
This paper will focus on some few types of GM crops that Nigerian would like to grow and the benefits they could bring. Some of the desirable characters that will be highlighted are;
1) Insect-resistant crops
2) Biofortified crops
3) Drought tolerant crops
4) herbicide resistant crop
Insect- Resistant Crops
For many years farmers experiences losses of about 40% of their harvested crops due to insect pests. The damage is usually cause by insect pests at the field or during the storage. Due to this problem biotechnologies provided the solution of this problem by producing crops that are resistant to insect pest with the use of bacteria which is not virulence that is Bacillus thuringiensis (Bt). Usually the Bt crops produce a toxic compound which affects insect, the compound is produced in an inactive form in the plant and will be activated when ingested by the insect and destroys them by affecting the insect gut.
However some of the crops that are insect resistant are Bt maize, maize is one of the most important sources of calories for the poor in our African countries. But insect (Stem-boring) causes significant yield losses of about 15 to 40% every year. If the maize were infected by this insect it produces life threatening toxic (Mycotoxins). The effect of this toxin to human being includes oesphageal cancer, liver cancer and also neural tube defects. It could be possible that when insect-resistant GM maize was planted all over the effects of this mycotoxin will be drastically decreases. Furthermore there is also Bt cotton and virus resistant cassava, which is resistant to cassava mosaic virus which causes great losses on cassava and Nigeria is one of the Africa’s most important cassava producers.
Biofortified Crops
Most of the developing countries depend on staple diet rice, maize, fresh fruit, vegetables meat and fish as their source of nutrient. These staple crops usually do not provide the essential nutritional (diet) needed by humans, which causes the problem of malnutrition in developing countries. Because of the high increase in human population in the world the problem of malnutrition is also increasing in the developing countries like Nigeria. In order to overcome these problem biotechnologies take strategy to enhance the nutrient content of some staple crops by the process known as biofortification. It has been noted by biotechnologies that the cereal grains planted in developing countries are poor source of lysine, vitamin A, folic acid, iron, zinc and selenium, which very essential for human growth and metabolism.
Nigeria is the fifth exporter of sorghum in the world. About 40 million Nigerians consumed sorghum as their source of energy food and also it was recognized as a potentially valuable industrial crop by the brewing industries, but it lacks protein and essential amino acids which can lead to malnutrition. Biofortified sorghum with macro and micro-nutrients, therefore, is considered a major step at resolving the nutritional challenge.
Drought Tolerant Crops
Plants are usually subjected to some physiological or morphological changes (biotic and abiotic stress) that affect the growth and development of the plant. This climatically changes are terms as abiotic stress (drought or high temperature) which affect the yield and quality of the crops.
Usually these environmental stresses lead to the formation of some radical (osmolyte) and reactive oxygen species. The basic strategies for engineering resistance to water-deficit stress have therefore focused on the production of osmoprotectants as a mechanism for overcoming the osmotic stress generated by water deficit.
Herbicide Resistant Crop
Famers have experienced great losses of about 50 to 70% in their crop yield and quality, due to the presence of weeds in their farm which they competed with their cultivated crops in terms of light and nutrients and also weeds harbor pests and diseases to their crops. Due to this problem biotechnologies provided an efficient way to tackle the problem of weeds by producing herbicide (weed killers). Some of most useful of these are broad-spectrum herbicides because they are active against a wide range of weeds. However, these can only be used at times when the crops is not itself vulnerable to herbicide action, this gives the opportunity to spray the herbicide at the most effective time to kill weed species without damaging the crop plants.
The Importance of GM crops in Nigeria
GM crops currently under undergoing field trials Nigeria are major staple crops in the country and possess significant importance in improving the economic situation by combating hunger s well as malnutrition and deploying safer agricultural practice in Nigeria. GM crops also ensure better and safer agricultural practices.
Set-Backs on GMO Crops
The major concern about the GM crops is based on the impact of the technology on the environment, human health and food safety. Some of the problems of transgenic crops are the development of super weeds, which could be due to frequent use of same herbicide-tolerant markers or transfer of herbicide-resistance genes to the wild population of weeds through cross pollination to related weedy types (gene flow). Moreover, it has been noted that due to increase in the use of herbicides will also increase the widespread of GM herbicide tolerance crops, which can cause contamination of the soil, ground water and unwanted impact to with non-GM crops in a given environment which can lead to genetic interchange with the wild species.
However there are two major types biosafety laws on GM crops labeling which will give the consumers choice either to use GM crops or not. The positive labeling which indicates the product has GM content (organic) in it and negative labeling which are GM free (non organic).
Conclusion
The GM crops play an important role in keeping and sustaining the growth of crops and also increases in yield and profit for the farmers. The benefit of GM crops is not only on the aspect of yield, quality and profit to the farmers but also help to protect the environment, human and animal health. The objection and concerns about the GMOs are important constraints to GM research and the commercialization of GM products. GM crops are not the only solution to the agricultural problem in Nigeria and Africa at large, but they do give farmers a tool to deal with those major problems.
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