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

more than 8,000 kg ha-1 showed that, among the crops sampled, 15% received from 4 to 5

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

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

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‐

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

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‐

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

cost, because are usually required multiple applications.

506 Insecticides - Development of Safer and More Effective Technologies

applications of insecticides and 6% received 6 to 8 applications for pest control.

borer (*Diatraeasaccharalis*).

ly in corn culture.

modern agriculture.

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‐ ously unknown bacterium.

The bacterium entomopathogenic (Bt) stands out on the world stage since 1938, when the first product formulated with this pathogen was released in France.

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

Since then more than 100 products were launched on the market and currently constitute more than 90% of gross revenues with biopesticides in [6, 7].

genetic features introduced were herbicide tolerance, product quality, virus-resistance and

Use of Biotechnology in the Control of Insects-Prague

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

509

**hectares) Biotech Crops**

<sup>1</sup> USA\* 69.0 Maize, soybean, cotton, canola, sugarbeet, alfafa, papaya, squash

**Area (million**

2 Brazil\* 30.3 Soybean, cotton, maize 3 Argentina\* 23.7 Soybean, cotton, maize

 South América\* 2.3 Maize, soybean, cotton Uruguay\* 1.3 Soybean, maize Bolivia\* 0.9 Soybean Australia\* 0.7 Canola, cotton Philippines\* 0.6 Maize Myanmar\* 0.3 Cotton Burkina Faso\* 0.3 Cotton

16 Mexico\* 0.2 Cotton, soybean

28 Costa Rica <0.1 Cotton, soybean

\* 17 biotech mega-countries growing 50,000 hectares, or more, of biotech crops.

**Table 1.** Global Area of Biotech Crops in 2011: by Country (Million Crops)\*\*.

29 Germany <0.1 Potato

**Total 160.0**

Source: in [34].

\*\* Rounded off to the nearest hundred thousand

19 Chile <0.1 Maize, soybean, canola

17 Spain\* 0.1 Maize 18 Colombia <0.1 Cotton

 Honduras <0.1 Maize Portugal <0.1 Maize Czech Republic <0.1 Maize Poland <0.1 Maize Egypt <0.1 Maize Slovakia <0.1 Maize Romania <0.1 Maize Sweden <0.1 Potato

5 Canada\* 10.4 Canola, maize, soybean, sugarbeet

6 China\* 3.9 Cottton, papaya, poplar, tomato, sweet paper

4 India\* 10.6 Cotton

7 Paraguay\* 2.8 Soybean 8 Pakistan\* 2.6 Cotton

resistance to insects in [33].

**Rank Country**

In some studies, this bacterium was considered inefficient in controlling *S. frugiperda*in [8, 9]. However, with the advances provided by new laboratory techniques and greater interest of researchers' positive results were obtained in [10]

The Bt a soil bacteria present in various continents, Gram-positive, aerobic and family Bacil‐ laceae, when environmental conditions become adverse can sporulate to survive these con‐ ditions in [11]. Are found in every terrestrial environments and also in dead insects, plants and debris in [12, 13, 14, 15, 16, 17, 18, 19]. The methods to isolate this pathogen are power‐ ful and usually easy to perform in [20, 21, 22, 23]. The number of cells obtained from Bt var‐ ied between 102 and 104 colony-forming units (CFU) per gram of soil, while in plants this number varies between 0 and ufc 100 cm-2 in [24].

Produces sporangia containing a endospore and crystalline inclusions of proteins that are re‐ sponsible for their action entomopathogenic, among which stands out the protein CRY. This crystal is composed of a protein polypeptide called endotoxin in [25]. When larval forms of insects feed on such proteins, initiates a series of reactions that culminate with the death of the same.
