Integrated Pest Management (IPM) is a sustainable approach to minimize the negative impacts of pests on crops while reducing the reliance on synthetic pesticides. This study was conducted in Kwara State Nigeria in 2023, to investigate the implementation of IPM practices and the occurrence of pesticide residues in okra among the farmers in Kwara State, Nigeria. A sample of 245 okra farmers were selected across 4 agricultural zones of Kwara State using a multistage sampling technique. An interview schedule was used to collect information from the farmers. Also, okra samples were collected from the farmers from each community of the Local Government Areas sampled. Data collected from the farmers were analyzed using descriptive and inferential statistics including frequency count, percentage, mean, standard deviation and Pearson Product Moment Correlation (PPMC). The Okra samples collected were taken to the laboratory for pesticide residue extraction using quick, easy, cheap effective rugged and safe (QuEChERS) technique and analysis was done using Gas Chromatography (GS)-Gas Mass spectrometer (MS). Results showed that most okra producers in Kwara State were smallholder farmers who, although practicing IPM, have limited knowledge of the technology. Some pesticide residues were detected in okra, two of which were present in quantities above the maximum residue limit, while others had quantities below the maximum residue limit. Therefore, This study recommends that the government improve extension services in the State by providing adequate funds and training extension agents who will provide comprehensive training to farmers on the types and application of IPM as an eco-friendly technology for preventing pesticide residue in okra.
Research Article
Integrated pest management practices and pesticide residue in okra among farmers in Kwara State
https://doi.org/10.21203/rs.3.rs-4712950/v1
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Extension services
Fipronil pesticide
Herbicide
Insecticide
Pest Control
Southern Guinea savanna
Okra (Abelmoschus esculentus (L.) Moench) is a crop widely grown in Nigeria and whose fruits are highly valued. (Ofuya et al., 2023). It is grown in other parts of the world including, West Africa, India, Brazil and the United States (Nath et al., 2020). It was reported that India is the world's largest producer of okra, followed by Nigeria and Sudan, and about 2 million hectares are cultivated annually in Nigeria (Idowu et al., 2022).
Okra is put to many uses in Nigeria. It is used as a soup thickener and to prepare relished slimy soups and sauces. The dried okra seeds contain nutrients and are used to prepare vegetable curds. It can also be roasted and ground as a coffee additive or substitute (Khoso et al., 2017). Okra leaves serve as good fodders for cattle and its mucilage is used for both medicinal and industrial purposes as it has been reported to serve as a plasma replacer or blood volume expander, for the glazing of papers and confectionery uses (Mohankumar et al., 2016).
Pesticides have been reported to increase crop yields, however, the possibility of causing health hazards as a result of misuse has been a major subject of concern. Reports of both acute and chronic pesticide toxicity experienced by people have been documented (OMAF, 2004). This is further corroborated by the report of Best-Ordinohia and Ataga (2017) that the indiscriminate application of the residual concentration of pesticides and their metabolites increased in harvested maize cobs due to inappropriate application of pesticides. Also, the higher levels of pesticide residues present in the imported Nigerian beans lead to the ban of this commodity from the European Union (The Guardian Newspaper, 2016). According to Jensen et al. (2011), the continuous ingestion of toxic pesticides, though in trace amounts, could accumulate in body tissues with adverse health consequences.
Integrated Pest Management (IPM) is a technology involving a strategic combination of available pest control techniques including the use of minimum rates of synthetic pesticides to effectively control pests below the economic threshold levels (Ofuya et al., 2023). This technique is considered to be the best approach for preventing pesticide residue in crops (Avav et al., 2006; Imoloame et al., 2021). According to (El-shafie, 2018), IPM was originally developed for agricultural pest management, but its scope has now expanded to include diseases, weeds and other pests. The aims of IPM are three folds, to sustain a safe ecosystem and environment through the reduced use of pesticides, to save money and increase profitability by reduced application rates of chemicals and to protect human and animal health through the provision of safe food devoid of pesticide residue (Dhawan & Peshin, 2009 ).
The amount of pesticides imported into Nigeria has increased over the years, suggesting increased use of these chemicals by farmers for the control of pests. Most farmers prefer pesticides to other methods for controlling pests (insects and weeds), due to ease of application and effectiveness (Sharifzadeh et al., 2018). However, pesticides are applied indiscriminately by Nigerian farmers, given their lack of relevant education (Imoloame, 2013). There is therefore the danger of pesticide excessive application which may lead to pesticide contamination and residues in the crops. To the best knowledge of the authors, no study has been conducted in the southern Guinea savanna zone of Nigeria to investigate the extent of pesticide contamination in okra resulting from pesticide usage and the adoption of IPM among the farmers. This justified this study.
Therefore, the general objective of this study was to investigate the use of Integrated Pest Management (IPM) techniques among okra farmers in Kwara State, Nigeria and to determine the presence of pesticide residues in okra samples, while the specific objectives were to describe the socioeconomic characteristics of respondents, find out the types of pesticides farmers use in the study area, determine to what extent okra grown by farmers is contaminated, examine the use of IPM practices for pest control among respondents and identify factors affecting the use of IPM practices for pest control in okra production.
Study area
The study area for this research was Kwara State made up of 16 Local Government Areas. The study is expected to cut across all the okra farmers in Kwara state as shown in Fig. 1.
Population, sampling technique, and sample size
The population of this study consisted of all the okra farmers in Kwara State. A total of 245 okra farmers were selected across the four zones of the Kwara Agricultural Development Project (KWADP), using a Multi-Stage sampling technique. The sample size was determined using Cochran’s sample size formula. The first stage involved the random selection of 30% of LGAs in each agricultural zone which gave 6 selected LGAs; viz: Baruten from Zone A; Edu from Zone B, Ilorin-south and Asa from Zone C and lastly, Ifelodun and Oyun LGAs from Zone D. At stage two, 30% of number of districts were randomly chosen from the selected LGAs, making 7 districts as listed in Table 1. After that, 10 communities were proportionately selected from these districts. Finally, 24 and 25 respondents were selected per community, making a total of 245 respondents, sampled for the study.
n = \(\:\frac{{Z}^{2}\:.\:\:P\left(1-P\right)}{{e}^{2}}\)
n = desire sample size
z = standard normal distribution = 95%
p = Estimated proportion of the population of interest = 155
e = desired margin of error = 0.05
n = 245.86
| Zone | LGAs | District | Communities | Respondents |
|---|---|---|---|---|
| A | Baruten | Ilesha | Shemga | 25 |
| B | Edu | Tsaragi | Saragi & Songa | 48 |
| C | Ilorin South Asa | Gaa Akanbi Owode Omupo | Tanke Budo Gambari, Bala, Ayegunle, Ayekale | 25 72 25 |
| D | Ifelodun Oyun | Idofian Okeogun | Ganmo Ijagbo | 25 25 |
| 6 | 7 | 10 | 245 | |
| Source: Field Survey, 2023 | ||||
An interview schedule was used to collect primary data from the farmers. Data collected were analyzed with descriptive and inferential statistics. These include frequency count, percentage, mean, standard deviation and Pearson Product Moment Correlation (PPMC).
Okra samples collection and pesticide residue extraction
Samples of okra fruits were procured from three farmers randomly selected in each of the communities in the six Local Government Areas. All the okra samples from the three points within each Local Government Area were gathered together and taken to the laboratory for pesticide residue extraction and analysis. The pesticide residues were extracted using the quick, easy, cheap effective rugged and safe (QuEChERS) method described by Anastassiades et al. (2003). About 100 g of the collected okra samples were homogenized with a blender and an aliquot of 5 g was then transferred into a 50 ml centrifuge tube, followed by the addition of 5 g of acetonitrile. The mixture was vortexed for 1 minute and was allowed to stand for 10 min. After, 10 min, 4 g of anhydrous MgSO4 and 1 g of NaCl were added to the mixture and the mixture was centrifuged for 5 min at 5000 rpm. Thereafter, 6 ml of the supernatant (upper organic layer) was transferred into another centrifuge tube (Supel QuE® dSPE) containing pre-weighed 900 mg of MgSO4 and 150 mg of PSA and was centrifuged at 5000 rpm for 5 min. About 5 ml of the supernatant was then acidified with 50 µl of 5% formic acid (10 µl/ml of extract) in acetonitrile to stabilize the extract and the extract was analyzed using GC-MS. All samples were analyzed in triplicate.
GC-MS Analysis for pesticide residue in okra
The separation of target analytes was achieved on a DB- 5MS fused capillary column containing 5% diphenyl and 95% dimethylpolysiloxane (30 m x 0.25 mm i.d x 0.25 µm film thickness). Helium (carrier gas) was set to a constant flow rate of 1.3 mL/min with a linear velocity of 42 cm/sec.
The GC column oven temperature program was set as follows. Initially set at 60 ℃ for 2 min, ramped at 30 ℃/min to 180 ℃, then ramped to 210 ℃ at 3 ℃/min, and finally to 280 ℃ at 20 ℃/min held for 5 min, for a total runtime of 24.50 min. The MS operation condition includes a transfer line of 300 ℃, an ion source of 200 ℃, and electron ionization (EI) of 70 eV. Determining the pesticides was done by matching the retention time of the standard and relative abundance and comparing the mass spectra of the standards and unknown with a mass spectra library (Ogah et al., 2011). The NIST library provided a list of the best matches based on the abundant mass-to-charge ratio.
Socio-economic characteristics of respondents
Table 2 presents results on socioeconomic characteristics of the okra farmers including age, marital status, and religion, among others. Results showed that the majority (92.2%) of the respondents were males, 38.0% of them were young adults between 31 to 40 years, and 31.4% were between 41 to 50 years. The aged and old comprised the lowest percentage (26.9%) of the respondents. A greater population (75.9%) of the respondents were full-time farmers, 35.1% were degree holders, 31.4% were diploma holders, and 20.4% had the first school leaving certificate (FSLC). These findings are consistent with the report by Adewole (2018) that okra farmers in Kwara State are mostly males and are married with formal education. Additionally, Imoloame et al. (2021) reported that the majority of farmers in Kwara State are young, between the ages of 31 and 40 years and are employed in the agricultural sector due to the high unemployment rate in Nigeria. This is in line with the report of (NBS, 2020), that 13.9 million youths were unemployed in Nigeria in 2020. Most of the farmers are still in their active and productive stages in life. They are also educated, a factor that will inspire them to be more open to accepting innovation such as IPM. The findings of Uwagboe et al. (2012) and Ejechi (2015) give credence to this because most of the farmers who were and adopted IPM were still in their prime age.
| Variables | Frequency | Percentage (%) |
|---|---|---|
| Gender | ||
| Male | 226 | 92.2 |
| Female | 19 | 7.8 |
| Age (years) | ||
| 18–30 | 9 | 3.7 |
| 31–40 | 93 | 38.0 |
| 41–50 | 77 | 31.4 |
| Above 50 | 66 | 26.9 |
| Farming status | ||
| Full time | 186 | 75.9 |
| Part-time | 59 | 24.1 |
| Qualifications | ||
| Degree | 86 | 35.1 |
| Diploma | 77 | 31.4 |
| FSLC | 50 | 20.4 |
| Others | 32 | 13.1 |
| Source: Field survey, 2023 | ||
Table 3 shows that a greater percentage of farmers (93.5%) applied insecticides to okra. In a review by Ofuya et al. (2023), Cypermethrin is the recommended insecticide for controlling insects in okra farms. However, it has been reported that synthetic chemicals are often indiscriminately used giving rise to health and environmental concerns (Stoll, 2001; Avav & Ayuba, 2016; Best-Odinohia & Ataga, 2017). Similarly, 73.1% of respondents applied 200ml /15 l or less of a knapsack sprayer on the volume of insecticides applied. This dose is considered to be significantly higher than the recommended rate which is 1.2ml/l. A higher dosage of the insecticide used by farmers in Kwara State could have toxic effects on both target and non-target organisms including man, especially when used in high concentrations (Agwu et al. 2016). Ekoja et al. (2023) believe that cypermethrin application on okra plants at the rate of 1.0 ml/ L at both vegetative and reproductive growth stages achieved significantly lower fruit damage by insects and consequently higher yields. The frequency of applications of insecticides by the respondents was mainly once (47.8%) and twice (42.5%). Furthermore, 60.0% of the respondents applied the insecticides at the early stage of growth and flowering. A great number of farmers in developing countries consider pesticide use as the panacea to protecting their crops from pest attacks, however, these pesticides are not utilized properly with the potential of resulting in pesticide residue or may increase insecticide resistance in the vectors as also reported by Matowo et al. (2020).
| Variables | Frequency | Percentage |
|---|---|---|
| Use of insecticides | ||
| Yes | 229 | 93.5 |
| No | 16 | 6.5 |
| Quantity of insecticide used (ml) | ||
| Not used | 19 | 7.8 |
| ≤ 200 | 179 | 73.1 |
| > 200 | 47 | 19.2 |
| Effectiveness of insecticide used for okra | ||
| Yes | 229 | 93.5 |
| No | 16 | 6.5 |
| Frequency of insecticide application for okra | ||
| Once | 117 | 47.8 |
| Twice | 104 | 42.4 |
| Thrice | 11 | 4.5 |
| Nil | 13 | 5.3 |
| Stage of insecticide application | ||
| Early stage of growth only | 37 | 15.1 |
| Early stage of growth and flowering | 147 | 60.0 |
| Early stage of growth, flowing and fruiting | 48 | 19.6 |
| Nil | 13 | 5.3 |
| Source: Field survey, 2023 | ||
Table 4, shows that herbicide is highly used among okra farmers in the study as 93.5% of them use the product, while 6.5% do not, for okra production. The brand of herbicide used by more than half of the respondents (56.1%) was Force Up (glyphosate). Other herbicides include Champion (12.6) and Para Force (6.7%). On the quantity of herbicides used, 90.2% of the farmers applied above 200ml per 15-liter knapsack sprayer for pre-emergence herbicides (82.0%). It has been reported that most farmers in different ecological zones in Nigeria use herbicides more than the other methods of weed control and that the most used herbicide by the farmers in Kwara and Niger States of Nigeria, is Force Up, mostly applied pre-emergence (Kolo, 2004; Imoloame 2013; Imoloame et al., 2021). The dose of herbicide applied may be higher than the recommended rates. Furthermore, the herbicides may be poorly applied as farmers are known not to calibrate their sprayers before use, resulting in insufficient or excessive application of herbicides (Imoloame et al., 2021)
| Variables | Frequency | Percentage |
|---|---|---|
| Use herbicides | ||
| Yes | 229 | 93.5 |
| No | 16 | 6.5 |
| Names of some herbicides used (*) | ||
| Champion | 45 | 12.6 |
| Force Up (Glyphosate) | 201 | 56.1 |
| Uproot | 10 | 2.7 |
| Gramazone | 16 | 4.5 |
| 4D | 11 | 3.1 |
| ParaForce | 32 | 8.9 |
| Gobara | 22 | 6.1 |
| Atrazine | 21 | 5.9 |
| Quantity of Herbicides used (ml)/knapsack sprayer | ||
| Nil | 16 | 6.5 |
| < 200 | 8 | 3.3 |
| > 200 | 221 | 90.2 |
| Types of herbicides used | ||
| Pre-emergence | 201 | 82.0 |
| Post-emergence | 4 | 1.6 |
| Pre and Postemergence | 24 | 9.8 |
| Not applicable | 16 | 6.5 |
| Source: Field Survey, 2023 | ||
Responses of the okra farmers regarding their level of knowledge about the use of IPM are detailed in Table 5. The majority of the farmers, 41.6% had limited knowledge, 35.1% indicated good knowledge, 10.6% indicated moderate knowledge, 9.4% indicated no knowledge and 3.3% indicated excellent knowledge. This finding implies that okra farmers in the study area had limited knowledge about the use of IPM. This may not be unconnected with the limited Knowledge of the extension staff, who are supposed to educate farmers, due to insufficient training (Agbamu, 2005). There may therefore be a need for farmers to be trained on IPM.
| IPM | Frequency | Percentage |
|---|---|---|
| No knowledge | 23 | 9.4 |
| Limited knowledge | 102 | 41.6 |
| Moderate knowledge | 26 | 10.6 |
| Good knowledge | 86 | 35.1 |
| Excellent knowledge | 8 | 3.3 |
| Source: Field Survey, 2023 | ||
Results presented in Table 6 indicate that the majority (98.4%) of respondents apply IPM for the management of pests in okra farms, despite their limited knowledge of the use of the technology (Table 5). A similar finding of IPM adoption among the majority of farmers was reported by Olasunkanmi et al. (2021). The type of IPM adopted in this study by a majority of the respondents (88.5%), was the combination of chemical and cultural methods (hoeing + insecticide + herbicide) while a few (4.5%) each, adopted chemical method only, herbicide and insecticides, cultural and chemical (hoeing + mulching + insecticide) and Cultural + biological (hoeing + insect-resistant variety) respectively. This implies that the combination of chemical and cultural methods (hoeing + insecticide + herbicide) was the highly adopted IPM practice for the control of pests in okra farms in the study area, despite their limited knowledge about this technology. This high adoption of IPM among farmers in Kwara State is a departure from the findings of Afuoku et al. (2012) that only 15.6% of the farmers in Central Agro-Ecology of Delta State Nigeria, adopted IPM and that there was a need to increase awareness of this technology and its benefits among the farmers. More than half of the population of the farmers (55.9%) depend on the extension workers for their source of information on agricultural innovation. However, such information may be inadequate, stale and unreliable due to the limited knowledge of the extension workers in Nigeria resulting from inadequate training and retraining (Ikuenobe et al. 2005; Imoloame et al., 2021)
| Variables | Frequency | Percentage |
|---|---|---|
| Do you apply IPM practices? | ||
| Yes | 241 | 98.4 |
| No | 4 | 1.6 |
| Types of IPM applied | ||
| Chemical method only: herbicide and insecticides | 11 | 4.5 |
| Chemical and cultural methods (hoeing + insecticide + herbicide) | 212 | 88.5 |
| Cultural and chemical (hoeing + mulching + insecticide) | 11 | 4.5 |
| Cultural + biological (hoeing + insect resistance variety) | 11 | 4.5 |
| Sources of information on IPM | ||
| Researcher | 58 | 23.7 |
| Extension | 137 | 55.9 |
| Intuition | 14 | 5.7 |
| Friends | 36 | 14.7 |
| Source: Field Survey, 2023 | ||
Constraints to use of IPM for okra production
The constraints to the utilization of IPM for okra production are presented in Table 7. Findings show that inadequate information on IPM from extension agents (mean = 4.24) ranked 1st, inadequate demonstration of new technologies (mean = 4.11) ranked 2nd, lack of proper training (mean = 4.06) ranked 3rd, inadequate irrigation facilities (mean = 3.88) ranked 4th, while the high cost of execution (mean = 3.58) ranked the least constraints to the use of IPM for okra production in the study area. These findings show that inadequate information on IPM from extension agents, inadequate demonstration of new technologies and lack of proper training were the leading constraints facing farmers on the use of IPM for okra production in the study area. The extension services offered in Nigeria have been described as weak and ineffectual depriving the extension workers of adequate training (Agbamu, 2005). Since extension is the bedrock of agricultural development, Imoloame and Olarewaju (2013) have suggested the need for the government of Kwara State to inject adequate resources towards the training of extension agents for better service delivery.
| Constraints | SA (%) | A (%) | SD (%) | D (%) | N (%) | Mean | Rank |
|---|---|---|---|---|---|---|---|
| Inadequate information on IPM from extension agents | 105(42.9) | 112(45.7) | 14(5.7) | 10(4.1) | 4(1.6) | 4.24 ± .874 | 1st |
| Inadequate demonstration of new technologies | 72(29.4) | 152(62.0) | 8(3.3) | 3(1.2) | 10(4.1) | 4.11 ± .856 | 2nd |
| Lack of proper training | 54(22.0) | 167(68.2) | 14(5.7) | 5(2.0) | 5(2.0) | 4.06 ± .736 | 3rd |
| Inadequate irrigation facilities | 46(18.8) | 150(61.2) | 28(11.4) | 17(6.9) | 3(1.2) | 3.88 ± .858 | 4th |
| High cost of execution | 25(10.2) | 127(51.8) | 66(26.9) | 20(8.2) | 7(2.9) | 3.58 ± .886 | 5th |
| Source: Field Survey, 2023 | |||||||
HO1: There is no significant relationship between gender, age and the use of IPM for okra production among respondents. However, farming status (r = 0.229), qualification (r = 0.235), years of experience (r = 0.132) and okra farm size (r = 0.228) showed a significant positive correlation with the use of IPM among okra farmers (Table 8). These findings suggest that that higher level of education, years of experience and farm size will lead to greater use of IPM for okra production in the study area. The result on the farm size of okra is consistent with the finding of Olasunkanmi et al. (2021) who also reported a positive relationship between farm size and the adoption of IPM practices among farmers in Nigeria. The significant relationship between education and the adoption of IPM implies that highly educated people are more inspired and open-minded to learn about innovations that will help to improve their farming practices and productivity. This category of people can be appointed to act as contact farmers for the diffusion of IPM in Kwara State of Nigeria.
| Do you apply IPM (for usage) | Pearson correlation (r) | Sig. (p-value) |
|---|---|---|
| Gender | 0.037 | 0.561 |
| Age | -0.27 | 0.673 |
| Farming status | 0.229 | 0.000** |
| Qualification | 0.235 | 0.000** |
| Years of experience | 0.132 | 0.039** |
| Okra farm size | 0.228 | 0.000** |
| Source: field survey, 2023 ** significant | ||
Pesticide residue analysis of okra
Table 9 presents the GC-MS okra analysis results. It shows that pesticide residues were not detected in the samples of okra obtained from Ilorin South, while in Ifelodun Local Government Area, only spiromesifen (0.38 mg/kg) was detected. In the case of Asa Local Government area, fipronil (0.02 mg/kg), propiconazole (0.006 mg/kg), phosmet (0.004 mg/kg), imidacloprid (0.29 mg/kg) and acetamiprid (0.21 mg/kg) residues were detected, while only imidacloprid (0.37 mg/kg) residue was detected in samples obtained from Oyun Local Government Area. Imidacloprid (0.24 mg/kg), phosmet (0.003 mg/kg) and propiconazole (0.04 mg/kg) residues were detected in samples from Baruten Local Government, while diazinon (0.008 mg/kg), imidacloprid (0.34 mg/kg) and propiconazole (0.004 mg/kg) were also detected in samples obtained from Edu Local Government Area. Acetamiprid and fipronil were detected at concentrations higher than the maximum residue levels of 0.2 mg/kg and 0.01 mg/kg, respectively. Other pesticides were detected at concentrations lower than the MRLs (spiromesifen 0.5 mg/kg; propiconazole, 0.01 mg/kg; phosmet, 0.05 mg/kg; imidacloprid, 0.5 mg/kg; and acetamiprid,02 mg/kg) (EU, 2024; FAO/WHO, 2024). The above result demonstrates that only insecticide residues were present in okra produced in Kwara State and no herbicide residues were found. This could be because herbicides were applied pre-emergence and all of it could have been metabolized in the plant system before the ripening stage. Previous research has shown that residues of herbicides in food are generally low and human intakes are normally below acceptable levels (Dewhurst, 2014). This finding is consistent with the report of Sondhia (2014), that at harvest, herbicides in various commodities were found either below the maximum residue limit or below detectable limits. According to Yiran et al. (2021), as soon as herbicides are applied, considerable processes immediately begin to impact the residue of those compounds in crops such as rainfall, and photodegradation. e.t.c. The indiscriminate application and poor use of insecticides could have resulted in the above maximum residue limits of Acetamiprid and fipronil insecticide in okra. This corroborates the report of Ellionet et al.,2000; Mukherjee and Gopal, 2003 that the indiscriminate use of pesticides leads to an undesirable load of pesticide residues in marketable vegetables, sometimes residues exceed their maximum limit and pose health hazards to customers. Similarly, Bempah et al. (2011), reported the presence of Gamma HCH, Endrin,,; DDE, Fenvalerate, Deltamethrin, Cyfluthrin, Cypermethrin and; DDE in okra obtained from the local market of Kumasi, in Ghana at different concentrations levels. Pesticide residues, such as Lindane, HCB, HCH, Aldrin, p,p; DDE and DDT, were also detected at different concentrations in okra obtained from Nigeria markets (Adeyeye & Osibanjo, 1999), although the levels were found below the maximum residue levels (MRLs). Although in this study, the other residues in okra are in trace quantities, below acceptable maximum residue limits, the accumulation of this residue in the human body over time could be toxic and dangerous. It is reported that many of the chemical residues, especially derivatives of chlorinated pesticides, exhibit bio-accumulation which could build up to harmful levels in the body as well as in the environment (Jayaraj et al., 2017). Irrespective of where the pesticide residue of okra was found to be high or low, farmers in Kwara State must be trained on integrated pest management (IPM) and its proper application as it is the best approach for preventing pesticide residue in crops. It is a strategy that integrates available pest control techniques including the minimum application of pesticides to minimize risks to human health and the environment.
| Agricultural Zones | Types of Residue | Quantity of Residue (Mg/kg) |
|---|---|---|
| Ilorin South | None | 0 |
| Ifelodun | Spiromesifen | 0.38 |
| Asa Local Government | Fipronil | 0.02 |
| Propiconazole | 0.006 | |
| Phosmet | 0.004 | |
| Oyun | Imidacloprid Acetamiprid Imidacloprid | 0.29 0.21 0.37 |
| Baruteen | Imidacloprid Phosmet Propiconazole | 0.24 0.003 0.04 |
| Edu | Diazinon Imidacloprid Propiconazole | 0.008 0.34 0.004 |
| Source: Field Survey, 2023 | ||
It can be concluded that Okra producers in the Kwara State were smallholder farmers who used both insecticides and herbicides for pest control. Glyphosate was the most commonly used herbicide for okra production. Although most of the farmers have adopted IPM practices consisting of the application of a combination of chemical and cultural methods (hoeing + insecticide + herbicide), their knowledge of this innovation was limited. This is because the okra farmers were not subjected to adequate training on IPM practices by the extension agents, who in turn lacked sufficient training. Lack of training and field demonstrations on IPM were implicated as the leading constraints facing okra farmers in adopting IPM practices. The GC-GM analysis conducted detected two pesticide residues Fipronil and acetamiprid that were above acceptable maximum residue limits in the okra samples collected from the Asa agricultural zone but the okra samples from other zones recorded traces of pesticide residues less than the maximum residue limits. There is therefore an urgent need to educate and train farmers on the application of IPM which advocates the use of minimum quantities of pesticides in combination with cultural and biological methods. There was a significant positive relationship between the adoption of IPM and farming status, educational qualification Years of experience and farm size
Recommendations
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Researchers must develop IPM strategies that are adaptable and tailor-made to fit local requirements. This is because IPM differs based on crop type, area and location.
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Extension agents should organize awareness, training and demonstration programmes on IPM practices for okra farmers. Such programmes should focus on the minimal use of pesticides in combination with other pest control options.
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The extension agents who are the major source of information to the farmers must be trained on the principles and practices of IPM. This can be achieved if the Kwara State Government adequately funds the Kwara State Agricultural Development Programme (KWADP). This will empower the latter to organize regular fortnightly and monthly meetings between the extension agents and researchers from the Universities and research Institutes for the transfer of technology and innovations.
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During the planning stage of an extension programme on IPM, full-time vegetables/okra farmers with higher levels of formal education, years of experience and large farm sizes should be selected as contact farmers who will facilitate and help in the diffusion of IPM technology.
Declaration of Interest: None
Author Contribution
Authors Name ContributionsE.O. Sought for funds, Administration of funds, Conceptualization, literature review, Methodology, Supervision, editing and writing of the first draft,Editing and writing of the final manuscriptO.Y. Review of literature, Methodology, Supervision, Data Analysis editing and writing of the first draft editing.L. B. Review of literature, Methodology, Supervision, Data Analysis, writing and editing of the first draft, editing. T.H. Methodology, Supervision,writing and editing of the first draft, editing.Review of literature, Methodology, Supervision, Data Analysis, writing and editing of the first draft, editing. Methodology, Supervision,writing and editing of the first draft, editing.
Acknowledgement
The authors want to thank the Tertiary Education Fund for the research grant awarded to the authors to carry out this study. We also appreciate the Laboratory Assistants, Mr. Mohammed Usman and Omotayo Jimoh for the role they played in collecting field and laboratory data.
Funding Declaration
This study was funded by the Tertiary Education Fund (TETFUND) of Nigeria
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No competing interests reported.