**6. The safety of the use of Btplants**

These days, according to the annual report of 2011 on the use of transgenic crops, the nonprofit organization International Service for the acquisition of AgriBiotech Applications (ISAAA) observed an increase of 94 times in planted area of 1.7 million hectares in 1996 to 160 million hectares in 2011 (Table 1), allowing biotech crops become more agricultural tech‐

The endless search for alternative methods of insect control-Prague has been held strongly by several research groups worldwide, due to the need of a more sustainable agriculture

In this way, farmers have adopted this technology Bt targeting an increasing effective pro‐ duction to sustainable agriculture in [36]. The benefits of this technology are: reduction of environmental effects on toxins, safety in use, efficiency, conservation of natural enemies

The first advantage is the production of protein *Cry*, by plants-Bt, which is not affected by environmental factors such as atmospheric fallout, light incidence, and high temperatures in [37]. In addition, the homogeneity of the protein, in plant tissues, allows a more efficient use of insecticide effect than the application (spraying) of biopesticides, Bt, based on plants. The second advantage is the possibility of a higher level of security in relation to insecticide for‐ mulated because the proteins and does not accumulate in fatty tissues, are not toxic to hu‐ mans and pets. Tied to these characteristics, the protein Cry, has no activity by contact, being necessary, the ingestion of the toxin by the insect, to have the effect of insecticide. The third advantage is the *Heliothisvirescens*control significant and *Pectinophoragossypiella*, for ex‐ ample, in Bt cotton culture, between 95 and 99% efficiency in [38]. The fourth advantage is the preservation of natural enemies, therefore, secondary pests can become a problem if the population of beneficial insects is reduced by the use of chemical insecticides of low selectiv‐ ity. The fifth benefit, no less important, is the reduction of fungal diseases. The lesions caused by insects, in the organs of plants, fungi infection, create opportunities mainly in the genus *Fusarium e Aspergillus*in [39]. The primary importance of these fungi is the presence of micotoxins, particularly fumosinsandaflatoxins produced by them. The fumosins can be fa‐ tal to horses and pigs in [40]. And aflatoxinis extremely toxic to animals and humans in [39]. The dramatic reduction of insect attack, leads to reduction of insect attack, and consequent‐

Currently the insect resistant transgenic plants expressing genes, inductors, an insectici‐ dal protein called Cry, derived from the bacterium *Bacillus thuringiensis*(Bt). The mecha‐ nisms by which proteins exert their effect are *Cry* elucidated by pore formation model

The mode of action of Cry proteins, produced by the plant, it is accomplished, orally, by susceptible insect. The process begins by solubilization of crystals in alkaline pH

nology adopted in the history of modern agriculture.

510 Insecticides - Development of Safer and More Effective Technologies

and reduction of fungal diseases.

ly, decreases the production of micotoxins.

**5. Mode of action of protein Cry**

discussed below:

and more committed to environmental preservation in [35].

In relation to the safety of the use of Bt corn plants as an example, several tests are conduct‐ ed to certify the safety of its use in the environment and in food and feed. Initially, the pro‐ tein *Cry* is tested in animal models, such as rats and mice, for the verification of the toxic potential. One of these tests, called acute toxicity consists in forced ingestion of a pure ani‐ mal protein by solution and on the observation of effects of this. The product only goes to the next steps of assessment if no effect is observed and diagnosed.

We can cite as an example the test performed with Safety, this protein in maize Herculex®. This protein was tested on mice to the level of 576 mg per kilogram of live weight and no side effect was observed. To be exhibited at similar level, a person weighing 70 kg would take almost 5 tons of raw corn grains. This without taking into consideration the aspect that the human digestive tract, not to have alkaline pH, would not be able to downgrade this protein crystal.

Other reviews include the potential to cause allergies as well as the corn grain consumption by other animals such as chicken and fish, and what is called substantial equivalence, which is comparing the nutritional profile of the genetically modified maize with conventional maize. The corn will only be released commercially and, therefore, will go to the market when, in these analyses, the nutritional content between the conventional and transgenic corn were exactly the same, except, of course, the presence of protein inserted.

In the analysis of environmental safety, non-target organisms, how insects from another or‐ der, class or species, natural enemies and beneficial insects like bees, for example, are ex‐ posed to proteins inserted or the pollen grains that express and are evaluated its effects.

If all tests present results within expected ranges and be proven that there is no risk of harm or damage to health and the environment, these damages are compiled and submitted to the competent authorities of the country where you intend to market the product for analysis and approval of use and consumption. In Brazil these analyses are made by the national technical Commission on Biosafety (CTNBio) and the approval of a product in one country does not guarantee that the same is approved in another. For example, the event MON810 (Yield Gard®) was approved in 1996 in the United States, in 1998 in Argentina and only in 2007 in Brazil.

China is one of the only exceptions in the world to require shelters, although this may be changing. Even though the refuges were a way to reduce the accumulation of resistance to Bt toxin, the large number of small properties makes this strategy is difficult to apply.

Use of Biotechnology in the Control of Insects-Prague

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

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The use of refuge in a developing country such as China becomes a challenging activity. Studies on policies of refuge on a large scale, in extensive agricultural systems of the United States of America, show that monitoring and implementation costs are negligible. Although this practice is reasonable in extensive production systems and with a small number of farms, they may not be suitable in developing countries. In developing countries like China, the agriculture sector is fragmented into millions of smallholdings, where each family has a

As a result, it is likely that the implementation of the strategy of refuge to the style (IE, all farmers planting Bt cotton are forced to grow cotton non-Bt with refuge) would re‐ quire a large implementation effort, making these types of strategies of refuge becomes unviable unless farmers received individual incentives to implement refuges based on self-interest. This is unlikely, since the build-up of resistance to Bt technology is a collec‐ tive evil (compared to the more common public as well) that is unlikely to be account‐

The area of refuge is the sowing of 10% of the area planted with Bt corn hybrids using Btnot equal size and cycle, preferably their isogenic hosts. The area of refuge should not be more than 800 m away from the transgenic plants. This is the average distance by dispersion of

All these recommendations are in order to synchronize the intersections of potential adults surviving in area of Bt corn with which emergency in the area of refuge. The structured refuge must be drawn according to the acreage with the Bt corn to plots di‐ mensions above 800 m in the shortest side (or Ray), cultured with Bt corn refuge will be needed in their tracks internal plots. Yet, according to the recommendation, in the area of refuge CTNBiois allowed the use of other methods of control, provided that they are

The worst drought in more than half a century in corn-producing region of the United States should reduce the crop in that country at the lowest level in five years, where their stocks will be reduced to the lowest level in 17 years. The initial productivity is bad in the few fields harvested in areas of the Midwest, which represents 75 percent of the area with corn and soybeans in the United States. With this the world, returned his eyes to the Brazilian

Brazilian agriculture won in the early 1980, an important milestone and helped the country to assume the rank among the major food producers in the world. Called when the off-sea‐

corn crop this year had one of the largest capacities of the whole story.

diverse set of cultures in [43].

ed for by individuals in [43].

adults of LCM in the field in [44].

not used Btbased bioinsecticide.

**7. Future trends for the Bt technology**

For the use of Bt corn, just the producer, in addition to using the seeds of biotech corn, fulfill two rules: the coexistence, required by law, and the rule of Insect Resistance management (MRI), recommended by (CTNBio).

The coexistence rule requires the use of a 100 m isolating surround of transgenic maize plan‐ tations of corn to retain without transgenic contamination. Alternatively, you can use a sur‐ round of 20 m, provided they are sown maize transgenic not 10 ranks (equal-sized and transgenic maize cycle) isolating the area of transgenic maize.

The CTNBiorecommendation for Insect Resistance management is the use of the area of refuge. This recommendation is the result of consensus that the cultivation of Bt corn in large areas will result in the selection of biotypes of target pests resistant to Bt toxins. Obviously, the monitoring of the infestation of plants is also important because, depend‐ ing on the used hybrid and intensity of infestation, the producer may need to adopt ad‐ ditional control measures.

The biggest concern with the use of Bt corn is on transgenic crops and coexistence of trans‐ genic crops do not. Coexistence is the set of agricultural practices allowing farmers grain production from conventional transgenic and organic crops, according to standards of puri‐ ty and to meet legal requirements for labeling. The adoption of the rules of coexistence is essential to preserve the freedom of choice of producers and consumers. Coexistence is also a topic particularly relevant when there is market incentive for the provision of non-trans‐ genic maize. Evidence of their practical viability is the coexistence of a considerable number of different varieties of open pollination still in use.

Showed that companies in possession of this technology must guide growers on the rules of coexistence. The producer also held technical information, stick to them proper‐ ly and conscious.

Information on packages of seed of Bt corn, there is a contract in which the producer, to open it, assumes the responsibility of following the rules of coexistence and the resistance management. Therefore, it is incumbent upon the producer responsibility of use of these rules. It is important to remember that the incorrect use of technology can take it to ineffec‐ tiveness in little time. If the producer is interested in paying more for Bt corn seed, is be‐ cause he believes in the benefits that this technology is bringing to your production system. Therefore, it must be motivated to use this technology in a responsible way (using the area of refuge), to take ownership of this benefit for much longer.

In relation to Bt cotton to China is the leader in this technology. In 2006 6.3 million farmers, or more than 60% of the number of farmers who have sown transgenic in the world in [42].

China is one of the only exceptions in the world to require shelters, although this may be changing. Even though the refuges were a way to reduce the accumulation of resistance to Bt toxin, the large number of small properties makes this strategy is difficult to apply.

The use of refuge in a developing country such as China becomes a challenging activity. Studies on policies of refuge on a large scale, in extensive agricultural systems of the United States of America, show that monitoring and implementation costs are negligible. Although this practice is reasonable in extensive production systems and with a small number of farms, they may not be suitable in developing countries. In developing countries like China, the agriculture sector is fragmented into millions of smallholdings, where each family has a diverse set of cultures in [43].

As a result, it is likely that the implementation of the strategy of refuge to the style (IE, all farmers planting Bt cotton are forced to grow cotton non-Bt with refuge) would re‐ quire a large implementation effort, making these types of strategies of refuge becomes unviable unless farmers received individual incentives to implement refuges based on self-interest. This is unlikely, since the build-up of resistance to Bt technology is a collec‐ tive evil (compared to the more common public as well) that is unlikely to be account‐ ed for by individuals in [43].

The area of refuge is the sowing of 10% of the area planted with Bt corn hybrids using Btnot equal size and cycle, preferably their isogenic hosts. The area of refuge should not be more than 800 m away from the transgenic plants. This is the average distance by dispersion of adults of LCM in the field in [44].

All these recommendations are in order to synchronize the intersections of potential adults surviving in area of Bt corn with which emergency in the area of refuge. The structured refuge must be drawn according to the acreage with the Bt corn to plots di‐ mensions above 800 m in the shortest side (or Ray), cultured with Bt corn refuge will be needed in their tracks internal plots. Yet, according to the recommendation, in the area of refuge CTNBiois allowed the use of other methods of control, provided that they are not used Btbased bioinsecticide.
