**1. Introduction**

The necessity of ever increasing agricultural production has induced farmers to use insec‐ ticides to improve yields and profits. The current agricultural mode of production is therefore based on intensive use of insecticides in order to ensure the high productivity by eliminating pests and diseases. Otherwise, others xenobiotics are often used as fertiliz‐ er to replace nutrients carried out in agroecosystems. However, in many places, the indis‐ criminate, prolonged and inappropriate use of these xenobiotics has been affecting the ecosystem and farmers health. Concerning insecticides on agroecosystems, the frequent applications can often cause pest resurgence, environmental pollution and human intoxi‐ cations, eliminate beneficial insects and enables the emergence of the phenomenon of pest resistance. Under this scenario, the search for other control methods aiming to decrease insecticides use, consequently reducing environmental pollution, the ecological imbalance and human intoxications is required. For this purpose, the understanding of the relation‐ ship between the various living organisms in the agroecosystems is essential to provide effective pest control. Living organisms present in the fields of production and its sur‐ roundings areas feature between them relationships for survival and preservation. In the specific case of insects, the study of chemical ecology focusing on the intra-and interspe‐ cific processes of choice and location of partners, hosts, food sources and shelter have had an important role in the pursuit of a sustainable agriculture. In order to offer more alternatives to control pests, early in the second half of the twentieth century studies were initiated for the development of pest management techniques based on behavioral manipulation of the target organism. When it became clear that insects use their senses to communicate with conspecific and other species of animals or plants, it was possible to

develop pest behavior research for the benefit of farmers and the environment. What compounds can be used to manipulate the pests and keep them below their level of dam‐ age? What behavior can be explored in Integrated Pest Management to reach sustainabili‐ ty in agriculture?

caused by pests. This determination allows knowing if the insects population density found in the crop can be tolerated. For this reason, one of the major uses of monitoring is the determination of early pest incidence; determine if the pest population has reached levels that will cause economic damage; as well as the detection of infested areas; inspection of quarantine

The Use of Behavioral Manipulation Techniques on Synthetic Insecticides Optimization

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The Integrated Pest Management (IPM) which recommends the use of control methods when the pest population reaches the Economic Injury Level (EIL) depends on the monitoring for an effective decision making. Pest monitoring is an extremely important tool, for through it, the proper time to use a control method is defined. If the adopted is chemical control, the insecticides application should be done only when the pest population density reaches control level. Thus, monitoring allows defining the spatial and temporal distribution of the insect. This strategy makes pest control more efficient and economic, reducing costs and time sampling, rationalizing sprayings and preserving biodiversity in the agroecosystems. In pest monitoring, several devices, such as traps, can be used spread out in the fields aiming to quantify specific insects. The number of insects measured is important in the decision making for determine whether the pest population has reached the EIL. At this stage of pest management, assessment is, therefore, qualitative. The important in this case is to obtain a correlation between the number of insects measured and its real population density. For monitoring, a large number of tools can be used as beat cloth, trays or traps. In the case of traps, several attractants can be

Pheromones are widely used in pest monitoring (Wyatt 1998) due to their specificity, selectivity and mainly for not affecting the health of workers and environment. They are chemicals used in conspecific communication, acting both in physiology, on individuals development; as in behavior, with a domino effect, prompting immediate action. The domino effect is what is explored in pest monitoring. Among the various existing types of pheromones, the sexual is the most widely studied in insect pest management (Vilela & Della Lucia 2001). The detection and recognition of pheromone molecules by insects are closely related to the olfactory system. The pheromone molecules reach the pores of the antenna sensilla, which are present in the thousands on antenna surface, vertically oriented and capture molecules in the air (Mustaparta 1984). Inside the antenna, the odor molecules collide with the dendritic membrane translating the chemical signal into electrical potential. The nervous impulse is transmitted to the central nervous system to produce a particular behavior in insects. These selective attractants are used in traps spread in the field that are to be monitored. Traps baited with pheromones must be sensitive enough to capture insects selectively, consistently and at low densities. Therefore, the knowledge of the target insect flight behavior is crucial when choosing the type of traps. Trap location and its height in the field, the most appropriate format and the most suitable pheromone mix for the site should be determined from studies of insect reproductive behavior. Additionally, the choice of the trap should be appropriate to the features of the land where the crop is located. Traps which have liquids as surface retention of insects are more difficult to be handled in a land of accentuated incline. In this case, models of traps where the insects are trapped by surfaces impregnated with adhesive glue would be more appropriate. These monitoring tools should be efficient enough to capture the target pest at low population

pest presence, among other uses.

used, such as pheromones, food and attractive colors.

At this current scenario of sustainable development, behavioral control is therefore ap‐ propriate by enabling to reduce the use of synthetic insecticides, which usually have broad spectrum and side effects to humans, beneficial insects and environment. Com‐ pounds and molecules involved in behavioral pest management such as feeding stimu‐ lants and semiochemicals, mostly sex pheromones, can be very useful to reduce synthetic insecticides dosage.

Practical applications of semiochemicals, including the sex pheromones, can lead to modifi‐ cation of pest communication permitting mating disruption, attraction to pint-source lures for monitoring, control by mass trapping, push-pull and attract-and-kill. Attractant lures can also be used for insect population control, in combination with large-capacity traps or a contact insecticide (Witzgall *et al*. 2008). The idea of controlling insect populations through speciesspecific manipulation of sexual communication, without adversely affecting other organisms, has been a driving force for pheromone research. According to Foster & Harris (1997) manip‐ ulation is defined as the use of stimuli that either stimulates or inhibits a behavior and thereby changes its expression. This has been achieved and technological shortcomings have been overcome through a joint effort between researchers, industry, and growers. Adoption of semiochemical-based pest management has increased in the face of dwindling conventional options, such as insecticides, increased government regulations and improved cost-competi‐ tiveness.

There are severals main elements of the behavioral manipulation method on which the tactics and strategies targeting the pest management should be based: knowledge about the behavior of the pest, identification of behaviors that should be handled, the ways in which the behavior is manipulated appropriately and the development of methods and tools that are used in the behavioral management of pests. This chapter will discuss pest monitoring and different behavioral manipulation techniques that can be used alone or in combination with other control methods and enable the optimization of synthetic in‐ secticides use in agriculture.
