**1. Introduction**

Productivity gains in agriculture are satisfactory with the use of genetically modified plants and the dependency of application of insecticides on crops becomes smaller over the years. The consequences of the development and marketing of corn genetically modified (GM) have been profound, and in 2011 the area planted in the United States of America (USA) with at least one GM trait corresponded to more than 88% of was over acreage.

In addition, the efficiency gains in the production chains were only possible thanks to the entrepreneurship and management of rural producers, who adopted the most modern tech‐ nologies available for science. Among these, stand: the tillage, fertilization and soil correc‐ tion, the techniques of integrated management of invasive plants, diseases and insect pest and the growing adoption of improved seeds with high productive capacity. It is observed that the simple hybrids corn came to dominate the market of seeds embedded in technolo‐ gies and seeds are more easily adopted by producers. This is the case of transgenic seeds, which in the culture of corn were widely adopted, including the major world producers of this cereal USA and Argentina.

In crops of corn, the losses caused by pests are limiting factor to achieve high productivity. The fall armyworm (*Spodopterafrugiperda*) is the main plague of corn in Brazil culture, caus‐ ing severe damage. The attack on the plant occurs since its emergence to the booting and the silking.However, the critical period is flourishing. Losses due to Caterpillar attack may re‐ duce production in up to 34%. Survey conducted among some 1,100 farmers who produce

© 2013 Piccinin et al.; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2013 Piccinin et al.; licensee InTech. This is a paper distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

more than 8,000 kg ha-1 showed that, among the crops sampled, 15% received from 4 to 5 applications of insecticides and 6% received 6 to 8 applications for pest control.

ques of direct modification of the DNA of a plant or a living organism, in order to change

Use of Biotechnology in the Control of Insects-Prague

http://dx.doi.org/10.5772/53302

507

Agricultural biotechnology varieties are used as a tool for agricultural research character‐ ized by gene transfer of agronomic interest (and, consequently, of desired characteristics) between a donor agency (which may be a plant, a bacterium, fungus, etc.) and plants, safely.

Studies dating this year in India and China show that the Bt cotton production in‐ creased 10% to 50%, respectively, and the use of insecticides has reduced in both coun‐ tries by 50%. In India, the producers have increased the income up to \$ 250 or more per hectare, the farmer's income increasing national \$ 840 million to \$ 1.7 billion last year. Chinese farmers saw similar gains with increasing yields on average \$ 220 per hectare, or more than \$ 800 million nationwide. It is important to emphasize the trust farmer in technology, with 9 of 10 Indian farmers reseeding the biotech cotton 100% year after

It is important to recognize the need for scientific research that point on the General mode of action of Bt toxins and also that their toxicity is influenced by several factors. However, it is known that, in General, the toxicity of the Bt toxin on target organisms depends on factors such as certain pH, proteases, and the receivers in [4]. On the other hand, and more specifi‐ cally, the extrinsic factors can also influence and co-factors in specific efficacy of Bt toxin on target organisms resistant and/or can also have an impact on the selectivity and toxicity to

Therefore, the emergence of modern biotechnology marks the beginning of a new stage for agriculture and reserves a starring role to molecular genetics. The advances in the field of plant genetics have the effect of reducing the excessive reliance on agriculture mechanical and chemical innovations, which were the pillars of the green revolution. In addition to increased productivity, modern biotechnology can contribute to the reduc‐ tion of production costs, better quality foods and for the development of less aggressive

The *Bacillus thuringiensis*, was discovered in 1901, by the occurrence of an epidemic of mor‐ tality of larvae of the silkworm in Japan. Researchers found that it was caused by a previ‐

The bacterium entomopathogenic (Bt) stands out on the world stage since 1938, when the

In 1911, in Germany, the Berliner managed to isolate and characterize this bacterium, baptiz‐ ing it *Bacillus* (by its cylindrical shape*) thuringiensis* (named after the German region of Tu‐ ríngea). In 1938, France formulations containing right-handed bacteria colonies were sold as

first product formulated with this pathogen was released in France.

insecticides and, in 1954, its mode of action was discovered and its use today.

precisely the characteristics of that organism in [3].

year and Chinese farmers using the technology.

non-target organisms in [5].

to the environment in [3].

ously unknown bacterium.

**3. The** *Bacillus thuringiensis* **(Bt)**

Other recent surveys, conducted by Embrapa maize and sorghum, have shown that in some regions the number of applications of insecticides for the control of Caterpillar-cartridge can reach 10. In addition, there is no efficient method of chemical control for at least two other important species: or the control of the corn earworm (*Helicoverpazea*) and the Maize stalk borer (*Diatraeasaccharalis*).

The insects have been one of the biggest causes of damage in food production being these losses of the order of 20 to 30% of world production in [1]. It is estimated that approximately 67,000 species of insects cause damage to plantations and tropical regions, usually the poor‐ est in the world, those who suffer most from the high incidence of insects-Prague in [2].

The attack of any pest depends on the development of culture, as well as the intensity of the attack, which can significantly affect the performance of the same. Chemical control is the primary measure used to prevent the immediate damage that reach the level of economic damage. Many times, the insecticides do not have the desired effectiveness and have a high cost, because are usually required multiple applications.

The insecticides used in pest control as an example in corn culture are often of low selectivi‐ ty, therefore can affect the population of natural enemies, favoring the proliferation of pests and even resurgence of others. Due to these factors, the search for alternatives that can mini‐ mize or even replace the conventional insecticides was intensified and, currently, the new tactics comprise a series of alternatives: resistant plants, selective insecticides, parasitoids and entomopathogenic microorganisms. Among the entomopathogenic *Bacillus thuringiensis* (Bt), notable for its wide use in the control of pest insects of the order Lepidoptera, especial‐ ly in corn culture.

Currently, transgenic production is widespread in almost all agricultural regions of the planet and with the adoption of biotechnology by greater productivity with the producers reaches lower use of insecticides. An example of this is the use of gene technology (Cry) of bacteria (Bt) in control of the main pests of maize culture. The Bt gene technology diffusion aims to make the environment more sustainable, decreasing the concentration of inert prod‐ ucts in foods using insecticides rationally. However, many challenges must still be over‐ come, with that biotechnology has as a fundamental role, seek new research, sustainable in modern agriculture.

### **2. Importance of biotechnology in the control of insects-prague**

Biotechnology is defined as a set of techniques for manipulation of living beings or part thereof for economic purposes. This broad concept includes techniques that are used on a large scale in agriculture since the early 20th century, such as tissue culture, the biological fixation of nitrogen and organic pest control. But the concept includes also modern techni‐ ques of direct modification of the DNA of a plant or a living organism, in order to change precisely the characteristics of that organism in [3].

Agricultural biotechnology varieties are used as a tool for agricultural research character‐ ized by gene transfer of agronomic interest (and, consequently, of desired characteristics) between a donor agency (which may be a plant, a bacterium, fungus, etc.) and plants, safely.

Studies dating this year in India and China show that the Bt cotton production in‐ creased 10% to 50%, respectively, and the use of insecticides has reduced in both coun‐ tries by 50%. In India, the producers have increased the income up to \$ 250 or more per hectare, the farmer's income increasing national \$ 840 million to \$ 1.7 billion last year. Chinese farmers saw similar gains with increasing yields on average \$ 220 per hectare, or more than \$ 800 million nationwide. It is important to emphasize the trust farmer in technology, with 9 of 10 Indian farmers reseeding the biotech cotton 100% year after year and Chinese farmers using the technology.

It is important to recognize the need for scientific research that point on the General mode of action of Bt toxins and also that their toxicity is influenced by several factors. However, it is known that, in General, the toxicity of the Bt toxin on target organisms depends on factors such as certain pH, proteases, and the receivers in [4]. On the other hand, and more specifi‐ cally, the extrinsic factors can also influence and co-factors in specific efficacy of Bt toxin on target organisms resistant and/or can also have an impact on the selectivity and toxicity to non-target organisms in [5].

Therefore, the emergence of modern biotechnology marks the beginning of a new stage for agriculture and reserves a starring role to molecular genetics. The advances in the field of plant genetics have the effect of reducing the excessive reliance on agriculture mechanical and chemical innovations, which were the pillars of the green revolution. In addition to increased productivity, modern biotechnology can contribute to the reduc‐ tion of production costs, better quality foods and for the development of less aggressive to the environment in [3].
