# Myths and Realities about Genetically Modified Food: A Risk-Benefit Analysis
## 4 The Application of GMOs to Agriculture and Food Production
### Protection against Insects and Tolerance to Herbicides  
In the 1970s, when it became evident that overusing chemical pesticides could pose serious negative consequences for human health and the environment, the FAO defined the Integrated Pest Management (IPM) concept. IPM is internationally recognized as a desirable plant protection standard that takes into account all the available pest control techniques and maintains pesticides and other interventions at levels that reduce or minimize risks for human health and the environment [88; 94]. The plants that have been genetically modified to resist pests are a cornerstone of IPM and can be used in conjunction with other pest management techniques. As previously stated, most GE crops provide tolerance to herbicides (e.g., glyphosate, 2-4 D, or glufosinate-ammonium), protection against lepidopteran and/or coleopteran pests, or a combination of both traits [80]. Some advantages of adopting GM crops for insect management are generally acknowledged, such as the potential to minimize pesticide use or high pest specificity [88; 95].  
Halfway through the 1990s, the introduction of GM crops led to substantial pest control system modifications [96]. For a long time, _Bacillus thuringiensis_, a Gram-positive bacterium that produces endogenous crystals upon sporulation, has been employed as a biological pesticide. The proteins contained in these crystals are poisonous for some insect larvae,mostly dipteran and lepidopteran species. Under the alkaline conditions of the insect midgut, the crystals break down and release proteins, which are proteolytically digested by proteases into less hazardous fragments (Figure 6). In 1985, the Belgian company Plant Genetic Systems was the first to develop GM plants with a tolerance to insects by inserting the crystal protein gene (bt2). This company created engineered tobacco plants that defend themselves from sensitive lepidopteran insects to the _B. thuringiensis_ toxin [97; 98]. This is how Bt-transgenic crops have been developed and cultivated since 1996 [96]. GM maize was one of the first transgenic crops to be commercialized. Resistant maize variants to glyphosate herbicides were produced by Monsanto, as well as Bt maize, a GM known to express one Bt toxin or more. Today, several crops show both glyphosate resistance, such as GM soybean, canola, cotton, sugar beet, and alfalfa, and insect resistance, which is conferred primarily by _B. thuringiensis_ toxins and is found primarily in cotton, soybean, and maize. Furthermore, eggplant (_Solanum melongena_ L.) is one of the most widely produced and consumed vegetables in Asia for its low cost, and Bt-transgenic eggplant crops have been grown in Bangladesh since 2014 [88].  
Nowadays, farmers and consumers demand more guaranteed food safety. The main purpose of an IPM strategy is to support the sustainable production of high-quality crops while reducing environmental impacts attributable to pests. Although GM crops may seem a potential short-term solution to control pests, a long-term vision is necessary because, by means of herbicide and Bt tolerance traits, weeds and insects will inevitably display resistance with time. For this reason, one of the IPM plan objectives is to limit dependence on a single technology. The application of an IPM strategy offers fairly clear benefits, including reduced risks to human health and the environment, fewer applications of chemical pesticides, and more durable pest management in crop production systems. GM crops are a powerful tool in these sustainable and eco-rational IPM strategies. However, it is important to collect all the information and experiences acquired with GM crops to understand the limitations of technology to enhance the durability and versatility of IPM plans for future crops [88; 96].