USE OF PESTICIDES IN THE IRRIGATION DISTRICT 075 OF NORTH SINALOA, MEXICO

The state of Sinaloa is known to be a large agricultural producer in Mexico. The use of pesticides in this region is in large quantities, which affects a large number of agricultural workers due to exposure to these chemicals. The objective of this work to identify the main crops, pests and pesticides used in the Irrigation District 075 for this research work a convenience sampling was carried out and 100 surveys were applied with questions related to the pests, crops and pesticides used by the workers agriculture in this region of northwestern Mexico. According to the results, the main crops planted and harvested are corn and beans, the main pests are the fall armyworm ( Spodoptera frugiperda ) and the whitefly ( Trialeurodes vaporariorum ) and the main pesticides are Tamaron and Cypermethrin. In conclusion, agricultural workers in Irrigation District 075 use pesticides considered of medium and high toxicity and have a preference for chemical control over biological control.


Introduction
In the north of the state of Sinaloa, highly technical agriculture is practiced, making it the country's breadbasket as it is the main producer of corn.As part of this intensive agriculture, the use of agrochemicals is in large quantities, always seeking the highest yield per hectare in crops and, above all, taking care of them from pest attacks.Although the pesticides used play an important role in controlling diseases in crops, some of them are considered moderately to highly dangerous due to their toxicity, which implies damage to people's health and the environment.(Del Puerto, 2014).
According to agricultural production statistics for the year 2020 from the Agricultural and Fisheries Information Service (2020), agricultural production in the state of Sinaloa represents 30% of the total at the national level, and grain corn production in the state represents 45.2%  2).According to INEGI (2020), the most produced pesticides are fungicides with an average of 45,290 tons in the last 14 years, followed by herbicides with an average of 31,239 tons in this same period.Although there are research works that used different methodologies that result in the main pesticides used in agriculture in the state of Sinaloa, this research work seeks to know the main crops, pests and pesticides used by agricultural workers in the Irrigation District.075 using as research instruments the interviews and application of surveys with the agricultural workers of this irrigation district.

Study area.
This Irrigation District 075 has an area of 228,337 hectares of irrigation and a total of 21,600 producers (CONAGUA, 2016), distributed in 13 irrigation modules as follows (Table 3).
Convenience sampling was applied taking into account the following characteristics of the agricultural workers surveyed: they work directly in the application of chemical pesticides, they know basic aspects about their preparation and application, they are committed to providing clear and reliable information, and they establish and work in the towns of Irrigation District 075, Sinaloa.were in the afternoon with the objective of being able to find the agricultural laborers in their homes.Tamaño y distribución de la muestra.
To determine the number of surveys to be applied, the population of the number of agricultural producers in Irrigation District 075 was taken as a basis, which according to the CNA is approximately 21,600.
According to López (2004), a formula to determine the number of surveys in qualitative research is: For a population size of 21,600 agricultural producers, and a margin of error of 10%, a sample size of 100 was obtained, distributed in the 13 modules.

Information collection.
Some considerations that were taken into account for the interview stage in which the questionnaire was applied are the following: • First, the reasons for the interview were explained, and it was clarified that the information provided was exclusively for research work, on the main pests and pesticides in irrigation district 075.
• It was also emphasized that the information is handled confidentially, even the name of the people interviewed was not requested, this gave greater confidence to the interviewees to freely answer the questions asked.
• The interview was ensured that it was in a place without noise and without distractions, in the same way that other people who wanted to intervene in the answers were not physically present or that the respondent did not feel free to answer.
• In the case of open questions, the interviewee's response was recorded faithfully, even when the answers were very absurd.The interviewee was not corrected or induced to give an answer, they were quick and concrete.If the question was not understood by the interviewee, the question was repeated.
• The questions were written in a simple way, without very technical terms, in which they did not have to make mental effort and/or calculations.They were also written in an objective and concrete way so as not to give rise to different interpretations.

Analysis of the data obtained.
To prepare the database and its analysis, the EXCEL 2013 program was used, each of the survey responses were captured, for each variable (question) the frequencies of the responses were added in order to identify the prevalence of these. .Likewise, bar or pie graphs were made to represent the prevalence of the responses of the variables.
The design used in the research was exploratory, transversal and descriptive, since information was collected at a single moment.
The information obtained in the interviews was coded in the following codes: -Causes of the presence of pests in crops.
Chart 2. Percentages of the number of hectares cultivated by agricultural workers.

Main crops
Of the agricultural workers surveyed, 57% plant only corn, 13% plant corn and beans, and 13% of them plant beans (Chart 3).The planting of corn predominates, since farmers state that its sale in the market is safer, and in which they can obtain greater profits.
Chart 3. Percentage of main crops in Irrigation District 075.
Agricultural workers do not risk planting other types of crops because they do not know if there will be demand for the product in the market or because they do not know its price.Corn, being the predominant crop and the only one for many farmers, becomes a monoculture practice, so insects find constant food, few predators and reproduce intensely, thus becoming a pest.Agriculture teaches us that plant diseases, insect pests and weeds became more severe with the development of monoculture (Altieri, 1994), which implies the use of more concentrated pesticides and in greater quantities to control them.

Main pests
The main pest that attacks corn is the fall armyworm (Spodoptera frugiperda) (Chart 4), which when found in the larva (worm) stage causes damage to the cornfields.The fall armyworm in its larval state feeds mainly on the buds of corn, which when the leaves spread appear with perforations like rows.(Negrete and Ángulo, 2000).
Chart 4. Percentages of the main pests in crops.
The fall armyworm, "It is the most voracious pest of corn crops since the worms are located in the buds of the plants.The early attack promotes a delay in development, and also causes damage to the tissues that form the cob" State Plant Health Committee of Guanajuato (CESAVEG, 2007).The main pests that attack the crops of Irrigation District 075 are presented in Table 5.

Conclusion
The pesticides used in irrigation district 075 are not within the group of pesticides prohibited in Mexico according to the 2016 COFEPRIS pesticide catalog, and comply with the regulations for their use in Mexico.
On the other hand, the main pesticides that are frequently used in Irrigation District 075 by agricultural workers are agrochemicals considered of medium and high toxicity, thus increasing the risks of damage to health and environmental contamination.
The agricultural worker uses the agrochemical with the objective and hope that it is effective, that it guarantees the control of pests, regardless of the degree of toxicity and the risk it represents to his health, as well as to the environment.Occasionally they use Trichogramma spp.As a biological control, chemical control is the one that predominates with 73% within the District.
Tabla 1. Porcentajes de los principales cultivos en los municipios de El Fuerte, Ahome y Chart 1. Hectáreas sembradas en el distrito de riego 075 Chemical fertilizers and pesticides are the most used in the state of Sinaloa, more than 60% of fertilizers, herbicides and insecticides are chemical (INEGI, 2019) (Table

Table 2 .
Percentage of technologies used in agriculture in the state of Sinaloa from October 2018 to September 2019.
/Kg), 4.7% were very dangerous (LD50 20 -200 mg/Kg) and 0.2% were extremely dangerous (LD50 < 20 mg/Kg).It is very important to control the use of pesticides in Mexico by the authorities, so that prohibited and/or restricted pesticides are not used in agricultural fields and in this way reduce damage to the environment and health of agricultural workers.In a study carried out by Hernández and Hansen (2011) in irrigation district 063, which mainly includes the area of Guasave Sinaloa, it was found that the pesticides applied to corn were Paraquat in 116,055 hectares, Abacmetina in 5,247 hectares of tomato, Chlorpyrifos in 14,523 hectares.hectares in chickpeas and Benomylo in 17,590 hectares of beans.

Table 3 .
Irrigation modules of Irrigation District 075.The survey and interviews with agricultural workers were used as research instruments.The survey was structured with multiple choice and open questions.In total, each survey consisted of 11 questions: irrigation module to which it belongs, age, education, daily hours of work.work,age at which they began to work in the crops, number of hectares worked, main crops, main pests, pesticides used in pest control, stage of agricultural activity in which pesticides are applied and use of biological control.The research instruments were applied in the months of September to February, which corresponds to the autumn-winter crop cycle.The visits made to the communities of Irrigation District 075 for the application of the surveys and interviews

Table 5 .
Main crop pests in Irrigation District 075.Although studies have shown that well-applied biological control can control pests efficiently, the culture of farmers, the promotion of chemical pesticides by agrochemical Chart 6. Analysis by irrigation modules.Use of biological control.