Cost-Bene t Analysis of Integrated Pest Management in Soybean Crops in the Midwest Region of Brazil

Denise Wochner UFGD: Universidade Federal da Grande Dourados Juliana Simonato Fundação MS José Jurca Grigolli Fundação MS Maycon Saraiva Farinha UFGD: Universidade Federal da Grande Dourados Luciana Mario Bernardo UNIOESTE: Universidade Estadual do Oeste do Parana Clandio Ruviaro (  clandioruviaro@ufgd.edu.br ) Universidade Federal da Grande Dourados https://orcid.org/0000-0003-3117-5359 Régio Toesca Gimenes UFGD: Universidade Federal da Grande Dourados


Introduction
The purpose of this study is to analyze the economic cost and benefit of using 150 integrated pest management in soybean production. Among the most severe pests to 151 soybean are bedbugs. They cause damage to crops because they suck the grains and pods, 152 thus decreasing the quality of grains (Fritz et al., 2008;Thancharoen et al., 2018). 153 Soybean is the most traded agricultural commodity in the world and the main agricultural   In this study, this parasitoid was used in an integrated pest management. In addition, this 166 study was conducted in the Midwest region of Brazil. This region is a productive highlight 167 in the production of monocultures such as soybeans (IBGE, 2020).

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Weekly samplings were carried out in all experimental areas at ten random points 209 per area. At each point, sampling was performed using the tapping cloth technique. The 210 number of pests per meter of line was recorded. In addition, the number of insecticide 211 applications used to control the caterpillar and the bedbug complex was recorded. This 212 sampling was carried out in both areas in order to quantify the pests in each treatment. In 213 the area of conventional pest management, monitoring was carried out as described 214 above. The control was carried out in accordance with previously established control 215 levels. This area was called conventional management because the pest control used 216 exclusively chemical insecticides.

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All applications were carried out with the help of a trailed sprayer with a capacity 218 of 2,000 liters of syrup. In the area of biological control, whenever necessary, applications 219 were made three days before each release or five days after the release of natural enemies 220 to avoid any interference from the released agents and possible interactions with the 221 sprayed broth. The data obtained were used to plot population fluctuation graphs of 222 soybean pests in the three areas of the assay. The data were subjected to analysis of 223 variance, and the treatment means were compared by Tukey test (p<0.05).

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The cost information for the investments made in each area was estimated  To carry out the cost-benefit analysis, it was decided to use the equation CB is the cost-benefit, PI is the price of the insecticide (price of the product at 238 the dosage used), EC is the environmental cost, PP is the product's performance, ECP is 239 the effective control period, and AL is the avoided loss.

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The equivalences of this analysis are: Score 1 = EPF between zero and one week; 294 Score 2 = EPF between one and two weeks; Score 3 = EPF between two and three weeks;

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After collecting this information, the environmental cost is estimated using the   There were no differences in the number of chemical insecticide applications 348 between areas. It is worth mentioning that, in this case, the management of the producer 349 followed the control levels and that the applications were carried out when they reached 350 the control level. Probably due to this characteristic, there was no change in applications.

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As for grain yield, there were no significant differences between treatments (Table 1). ------7.23 Note: Means followed by the same lowercase letter on the row do not differ statistically from each other by 356 t test at 5% probability. ns not significant; * and ** significant at 5% and 1% probability, respectively.

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Area 2: In this area, the releases of T. podisi contributed to a smaller population

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As for the number of chemical insecticide applications for the control of  ------9.45 Note: Means followed by the same lowercase letter on the row do not differ statistically from each other by 386 t test at 5% probability. ns not significant; * and ** significant at 5% and 1% probability, respectively.     There was a positive effect of IPM and a reduced use of insecticides. As for grain yield, 412 there were no significant differences between treatments (Table 3).  ------9.71 Note: Means followed by the same lowercase letter on the row do not differ statistically from each other by 417 t test at 5% probability. ns not significant; * and ** significant at 5% and 1% probability, respectively.

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There are singularities in each evaluated area. In Area 1, producer management 420 and IPM were similar, with no need for chemical insecticide applications in any of the 421 areas and five chemical applications to control bedbugs. However, in Area 2, the producer 422 management area required ten chemical applications, five for the control of caterpillars 423 and five for the control of bedbugs, while in the IPM area, using biological control, no 424 chemical application was necessary to control caterpillars and only four were necessary 425 to control bedbugs.

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In Area 3, no chemical application was necessary to control caterpillars.

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The IPM reduces the use of pesticides and consequently reduces costs in pest 506 management, but the adoption of biological control replacing chemicals is still more 507 expensive. One of the probable reasons for this scenario is the lack of public policies 508 seeking a sustainable agriculture in Brazil. In Brazil, there is no fiscal incentive for the 509 creation, commercialization, and use of biological agents, hindering the market 510 competition for this type of management. For environmental cost analysis, the cost and benefit components were analyzed 515 separately to clearly demonstrate the results obtained in the model used. As Table 5 516 shows, the pesticides are arranged by active ingredient; some names are repeated because 517 the doses used in different areas were not the same, thus being necessary to present each 518 product according to the dose used.

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The items presented are price per dose in US dollars, general index (the sum of 520 scores of operator safety, toxicity to natural enemies, environmental persistence, and 521 toxicity to biological indicators -birds, bees, and aquatic organisms -the arithmetic mean 522 was calculated and rounded to the nearest whole number), and environmental and total 523 cost. Table 5 shows all results of calculations.  As Table 5 shows, the price is the amount the producer pays for the product per In Area 1, the difference in values for conventional and IPM management is 547 considerably great, indicating a low cost-benefit ratio for the use of biological control 548 (Table 6). It is noteworthy that this farmer adopts IPM, with sampling and decision-549 making of application based on control indexes, so that this is probably the reason for the 550 great difference observed. In Area 2, the difference between conventional management 551 and IPM with biological control decreased in relation to Area 1 and amounted to US$ 552 29.20/ha (applied by the producer) or US$ 7.54/ha (applied by the third party company).

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In Area 3, the difference in the results between the conventional area and the area with 554 IPM and biological control varied between US$ 8.70/ha (applied by the producer) and 555

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Due to the use of more aggressive products, which consequently obtained the 565 highest environmental cost, Area 3 had an increase in costs, showing that environmental 566 cost analysis is essential for the decision making by the producer, who opts for products 567 that are less harmful to the environment, besides this being one of the principles of IPM.

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Another aspect observed in this work is the economic impact of using IPM. Area 1 569 showed the biggest difference between producer management and IPM with biological 570 control. This happens because the producer performs the applications only when 571 necessary, underestimating the effects of the release of biological control agents.

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Estimating the economic costs of environmental risks is essential to weigh 573 differences between risks and to integrate environmental and economic data. Taking 574 environmental risks into account is an important analysis to improve decision-making 575 when using IPM (Higley, Wintersteen, 1992).

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The indirect costs of using pesticides for the environment and public health need breaking the paradigm that only agrochemicals generate high productivity. These results

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show that the producer can be highly productive and still reduce environmental impacts.

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As for the feasibility of adopting biological pest control in soybean crops to 619 replace conventional management, the use of agrochemicals is still more economically 620 viable than the biological control. This result shows that the lack of public policies, associated with the encouragement of commercialization, use of biological control, and 622 adoption of IPM practices, discourages the adoption of sustainable practices.

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The environmental cost analysis model proposed in this study is able to assist 624 the producer in choosing the products for the farm, prioritizing the reduction of 625 environmental impacts. It is hoped that this study serves as a basis for future research 626 seeking to promote the adoption of IPM practices associated with biological control.