**1. Introduction**

Chemical substances have been used excessively in order to increase the agricultural productivity since the 1940s. Applications initially led to an apparent increase in yield. However, in the later process, effectiveness of these substances decreased due to the development of resistance against chemicals, particularly used in combating agricultural pests, thus this situation resulted in either excessive use of them to obtain better response or development of new drugs with high expenses. Moreover, in this course, human, animal and environmental health problems are reached much more serious extent besides the economic losses [1]. This situation, particularly, in the developed countries has led people to consume more safe products. The current approach is more comprehensive, which ensure the dissemination of sustainable practices in every production area in order to leave a healthier world for future generations.

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© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, © 2017 The Author(s). Licensee InTech. This chapter is 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.

Organic farming, emerged in this context, is accepted as the farming not allowing the use of any of the substances/applications such as growth promoters, antibiotics, genetically modified organisms and irradiation, which are considered to be harmful to human health, and providing safer foods concerning nitrates, pesticides and harmful elements (heavy metals, particularly cadmium) and rich in phenolic compounds and vitamins [2, 3].
