Misuse Of Pesticides Research Articles

Pilot Educational Intervention to Promote Safe Pesticide Use Practices Among Farmworkers in Nepal.

The misuse of pesticides among farmworkers in Nepal is commonplace. To address this, we implemented a pilot educational intervention (three modules delivered over 3 days and lasting approximately 3 h each) in Kavre District of Nepal. Modules included: (i) health and environmental effects of pesticides, (ii) use of personal protective equipment, and (iii) label literacy and behavioral factors that influence pesticide exposure. In addition, 10 posters with key messages from each of the modules were hung throughout communities. Surveys were administered to cross-sectional convenience samples of farmworkers at baseline (n = 106) and 1 year later (n = 98). Practices relating to pesticides at baseline and endline were compared using multivariable logistic regression to adjust for differences in demographic and socioeconomic characteristics between the samples. Compared with the baseline sample, farmworkers in the endline sample were significantly more likely to report: getting information regarding the amount of pesticides to use from experts or pesticide labels (versus personal judgment); wearing gloves while mixing pesticides; wearing boots while working in the field; using personal hygiene practices after handling pesticides such as bathing or washing hands and feet; changing clothes after handling pesticides; checking the wind direction before spraying; and delaying entry for a longer period of time after spraying. These results suggest that a simple educational intervention can improve pesticide handling practices among farmworkers in Nepal. Future research should explore the impact of such interventions on pesticide exposure levels and health outcomes, and the potential to scale up these programs nationally.

Use of Insecticides in Agriculture and the Prevention of Vector-Borne Diseases: Population Knowledge, Attitudes, Practices and Beliefs in Elibou, South Côte d'Ivoire.

People’s knowledge, attitudes, practices and beliefs (KAPB) pertaining to malaria are generally well described. However, little is known about population knowledge and awareness of insecticide resistance in malaria vectors. The aim of this study was to investigate KAPB related to insecticide resistance in malaria vectors due to the use of insecticides in agriculture and the prevention against mosquitoes. In mid-2017, we carried out a cross-sectional survey in Elibou, South Côte d’Ivoire, employing a mixed methods approach. Quantitative data were obtained with a questionnaire addressed to household heads. Interviews were conducted with key opinion leaders, including village chiefs, traditional healers, heads of health centres and pesticide sellers. Focus group discussions were conducted with youth and elders. A total of 203 individuals participated in the questionnaire survey (132 males, 65%). We found that people had good knowledge about malaria and mosquitoes transmitting the disease, while they felt that preventing measures were ineffective. Pesticides were intensively used by farmers, mainly during the rainy season. Among the pesticides used, insecticides and herbicides were most commonly used. While there was poor knowledge about resistance, the interviewees stated that insecticides were not killing the mosquitoes anymore. The main reason given was that insecticides were diluted by the manufacturers as a marketing strategy to sell larger quantities. More than a third of the farmers used agricultural pesticides for domestic purposes to kill weeds or mosquitoes. We observed a misuse of pesticides among farmers, explained by the lack of specific training. In the community, long-lasting insecticidal nets were the most common preventive measure against malaria, followed by mosquito coils and insecticide sprays. The interviewees felt that the most effective way of dealing with insecticide resistance was to combine at least two preventive measures. In conclusion, population attitudes and practices related to insecticides used in agriculture and the prevention against mosquitoes could lead to resistance in malaria vectors, while people’s knowledge about insecticide resistance was limited. There is a need to raise awareness in communities about the presence of resistance in malaria vectors and to involve them in resistance management.

Pesticides handling practices among potato growers in Kavrepalanchok, Nepal

The rate of pesticide application in the agricultural field is surging. Farmers are getting exposed to pesticide hazards from the misuse and unsafe handling of pesticides. The study was conducted among 101 potato growers in Kaverpalanchok district of Nepal in 2018. The objective of the study was to assess the knowledge, status, and pesticide handling practices among potato growers. Around 94% farmers applied pesticides against early and late blight. Only 5% growers treated seed before potato sowing. About 93 and 73% farmers sprayed pesticides 2-10 times/season into the field and spent 2-6 hours/pesticide spray respectively. More than 2/3rd growers did not read the pesticide labels, and nearly 95% growers received information on pesticide applications from agrovet rather than authorized government bodies. Only 13% farmers had received Integrated Pest Management (IPM) training. However, 1/4th of them had practiced IPM techniques. The majority of the growers used masks, rubber boots, and long-sleeved clothes during pesticide handling. Nearly 2/3rd growers threw pesticide containers anywhere in the environment. Concerned authorities should provide IPM training, skill-building programs on pesticide handling and awareness on waiting period and environmental hazards to avoid pesticide risk.

Managing the root rot disease of sunflower with endophytic fluorescent Pseudomonas associated with healthy plants

Use of pesticides is an effective way to control plant diseases but their excessive or misuse of chemical pesticides can cause environmental pollution. Whereas, biological control of plant diseases with saprophytic bacteria and fungi still giving inconsistent results, utilization of endophytic bacteria in plant disease management has been appeared as a new hope. In current study, 40 isolates of endophytic fluorescent Pseudomonas (EFP) were isolated from 20 healthy plants grown in experimental field of Karachi University and agricultural fields of Karachi and its suburb and identified according to Bergey's manual. Identification of ten potential isolates was also confirmed using genus-specific primer set i.e. PA-GS-R F 5′-CACTGGTGTT- CCTTCCTATA-3′ and PA-GS-F 5′-GACGGGTGAGTAATGCCTA-3’. Phylogenetic reconstruction associated the fluorescent Pseudomonas as a descendent of P. monteilii and P. aeruginosa. Out of 40 isolates, 10 caused growth inhibition of all 4 test root rotting fungi Macrophomina phaseolina, Rhizoctonia solani, Fusarium solani and F. oxysporum in vitro. Most of them were found to produce hydrogen cyanide, volatile antifungal metabolites, ammonia and indole acetic acid besides solubilizing phosphate. In field plot experiments five selected isolates of EFP were applied as soil drench, significantly suppressed root rotting fungi of sunflower. EFP-121 was found highly effective in improving plant height and fresh shoot weight, than other isolates and carbendazim, a fungicide. Endophytic fluorescent Pseudomonas associated with healthy plants are seems to be an effective alternate to chemical fungicides.

Investigation of pesticide residues in water, sediments and fish samples from Tapi River, India as a case study and its forensic significance

This research is a case study on detection of pesticides in river water, sediment as well as fish samples from Tapi River, among the major rivers of Gujarat, India. To investigate the misuse, concentration level and occurrence patterns of persistent pesticides, samples were collected from the river. Chlorpyrifos, methyl parathion, hexachlorocyclohexane (HCH), dichloro diphenyl trichloroethane (DDT) and endosulfan were analyzed by gas chromatography technique with flame ionization detector (FID). Scanty reports are available, but after 1999, no such data are reported as some of these pesticides have been banned. Although these pesticides are still in use which we observed from the obtained results. In this river, the amount of endosulfan, chlorpyrifos, and methyl parathion was observed in surface water with concentrations of 37.56 µg/L, 0.86 µg/L and 0.43 µg/L, respectively. Endosulfan, DDT and methyl parathion detected in sediment were 38.38 ng/g, 0.65 ng/g and 0.77 ng/g, respectively. In fish samples, levels of endosulfan, chlorpyrifos, and methyl parathion detected were 101.28, 0.392, and 3.49 ng/g correspondingly. Results showed that highly toxic pesticides are still being used in the surrounding area, and there is an urgent need for enforcement of rules to control the production and application of such pesticides.

Pesticides used by farmers in the arabica coffee growing regions of Uganda

Coffee is generally stressed by several biotic constraints including insect pests, diseases, weeds, nematodes among others, due to its nature. In response, farmers use all sorts of pesticides so as to manage these problems. However, detailed studies to determine the types of pesticides used in the diverse Arabica coffee agro-ecologies of Uganda are yet to be conducted. This information is vital for guiding research, policy and other agendas on pesticide issues, since their misuse can cause serious negative effects on humans, livestock and environment. A questionnaire was therefore, administered to 325 households in the 3 major Arabica coffee growing regions of Uganda (Mt. Elgon, West Nile and southern), with the aim of determining which pesticides are commonly being used by farmers. The study specifically aimed at investigating which pesticides have been banned in Uganda but still being used by farmers in these Arabica coffee agro-ecologies. Results showed that pesticides use in the Arabica coffee growing regions of Uganda was limited, with only 23% of the farmers using them. The highest percentage of farmers (39%) using pesticides was recorded in the southern region, while the lowest percentage of farmers (11%) was observed in West Nile region. A total of 22 of pesticides namely, 13 insecticides (59%), 5 fungicides (23%) and 4 herbicides (18%) were being used by farmers. Most of the pesticides recorded (64%) belonged to class II chemicals which are defined as moderately hazardous. Farmers should, therefore, be encouraged to use these pesticides instead of the class I chemicals which are defined as highly hazardous. The commonest insecticide was cypermethrin, being used by 15.4% of the farmers, while mancozeb was the most common fungicide, used by 7.7%. On the other hand, glyphosate was the most commonly used herbicide, by 15.4% of the farmers. The study further revealed that three insecticides - carbofuran (Furadan 5), dichlorvos 100% (Lava 100% EC) and fenitrothion (Sumithion/Fenitrothion) and one herbicide, gramoxone (Paraquat), which were being used by farmers, have been banned from use in Uganda. However, none of the fungicides observed has been banned from use in Uganda. Thus, farmers in all coffee growing agro-ecologies should be educated on pesticide use particularly those that have been banned from use. This will reduce pesticide misuse, toxicity and exposure.

Long-term Cultivation and Fertilizer Changes Soil Chemicals

This paper briefly summarizes the effects of long-term cultivation and fertilizer on soil chemistry in recent years. The effects of different topography, long- term fertilization, different farming patterns, and different drainage modes on the dynamic changes of soil pH, large amounts of elements (effective phosphorus, quick- impact potassium), and medium and small elements (exchangeable calcium, magnesium) were mainly introduced and discussed. Due to the misuse of chemical fertilizers and pesticides in recent years, the phenomenon of soil chemistry has become increasingly serious. Only by comprehensively analyzing the effects of farmland management measures on soil chemistry and understanding the changing laws of soil chemical quality can sustainable agriculture and eco-friendly agriculture be better developed.

Cloning, phylogenetic research, and prokaryotic expression study of the metabolic detoxification gene EoGSTs1 in Empoasca onukii Matsuda.

Due to the misuse of chemical pesticides, small green leafhoppers (Empoasca onukii Matsuda) have developed resistance to pesticides, thereby posing a serious problem to the tea industry. Glutathione S-transferases (GSTs) are an important family of enzymes that are involved in pesticide resistance in Empoasca onukii Matsuda. Empoasca onukii GST sigma 1 (EoGSTs1, GenBank: MK443501) is a member of the GST family. In this study, the full-length cDNA of EoGSTs1 was cloned by reverse transcription polymerase chain reaction (qPCR), and its taxonomic identity was examined. Furthermore, we performed bioinformatics and phylogenetic analyses of the gene and structural and functional domain prediction of the protein. The results demonstrate that EoGSTS1 belongs to the Sigma family of GSTs; the full-length EoGSTs1 cDNA is 841 bp with a 624-bp coding region that encodes a 23.68932-kDa protein containing 207 amino acids. The theoretical isoelectric point (IEP) was calculated to be 6.00. Phylogenetic analysis indicates that EoGSTS1 is closely related to the Sub psaltriayangi subfamily of the Cicadoidea superfamily in order Hemiptera, whereas it is distantly related to Periplaneta americana of order Blattodea. Amino acid sequence alignment of EoGSTS1 and GSTs from four other insects of order Hemiptera revealed protein sequence conservation. Tertiary structure analysis and structural domain functional predictions of the protein revealed that EoGSTS1 contains nine α helices and two β sheets with one conserved GST domain. The results of enzyme activity assay showed that recombinant EoGSTs1 (rEoGSTs1) protein had catalytic activity for substrate 1-chloro-2,4-dinitrobenzene (CDNB) and exhibited the highest activity at pH 7 and 25 °C. The Michaelis constant Km of rEoGSTs1 protein was 0.07782 ± 0.01990 mmol/L, and the maximum reaction rate Vmax was 12.15 ± 1.673 µmol/min⋅mg. Our study clarified the taxonomic identity of small green leafhopper EoGSTs1 and revealed some properties of the gene and its encoded protein sequence. According to the catalytic activity of the rEoGSTs1 enzyme on the model substrate CDNB, we infer that it functions in the degradation of exogenous substances.

Next generation biological control – an introduction

Next generation biological control – an introduction

Ecological risk assessment of agricultural pesticides in the highly productive Ndop flood plain in Cameroon using the PRIMET model.

Flood plains can make a significant contribution to food security due to their rich agricultural and aquaculture potentials but the misuse of pesticides in these ecosystems may seriously threaten their sustainability. We have assessed the risk of commonly used pesticides by rice and vegetable farmers on two major streams in the Ndop flood plain in Cameroon using the PRIMET model. Thirty pesticide formulations were identified containing 17 active ingredients belonging to fungicides (7), herbicides (3), and insecticides (7). Out of these, five posed acute and/or chronic risks to the streams. Chlorpyriphos-ethyl (ETR = 655), chlorothalonil (ETR = 250), and cypermethrin (ETR = 190) posed a definite acute risk to both streams. These pesticides also posed possible chronic risks with cypermethrin also posing a definite chronic risk (ETR = 1658) to fish in one of the streams. Mancozeb (ETR = 2.2) and λ-cyhalothrin (ETR = 2.8) posed a possible acute risk to both streams. It was interesting to note that most pesticides, including some of those that posed a risk, were applied at lower doses than their respective recommended doses. Differences in ETRs were also observed in the two streams with higher values occurring in the stream having a lower concentration of suspended solids. The higher velocity of the Ngwala-Mesaw stream did not affect the acute risk posed by pesticides. Pesticide toxicity was an important determinant in the risk posed and we recommend that appropriate mitigation measures be put in place to reduce the risk of these pesticides such as the implementation of an appropriate buffer zone between the edge of field and water body.

Significant role of supercritical fluid chromatography - mass spectrometry in improving the matrix effect and analytical efficiency during multi-pesticides residue analysis of complex chrysanthemum samples

As an important “food and drug dual-use” product, chrysanthemums are widely used in both botanical medicine and food applications. However, the misuse of pesticides during chrysanthemum cultivation makes pesticide residue monitoring crucial. The aim of the present work was to address this practical demand for the simultaneous determination of multiple pesticide residues in various species of chrysanthemums. Both the sample pre-treatment and instrumental methods were systematically investigated. Seven chrysanthemum samples were extracted using acetonitrile and purified by dispersive solid-phase extraction with amino-modified multi-walled carbon nanotubes (MWCNTs-NH2) and C18 as the cleanup co-adsorbents. After optimizing the amounts of MWCNTs-NH2 and C18, matrix effects could not be avoided during LC-MS/MS analysis of 112 pesticides, although satisfactory recoveries were obtained. The use of SFC-MS/MS was evaluated, which demonstrated the significant positive role of SFC-MS/MS in reducing the matrix effects during pesticide residue analysis. In addition, the use of SFC-MS/MS permitted a shorter run time and afforded greater analytical efficiency. Method validation was further performed to evaluate the linearity, sensitivity, recovery, and precision of the developed method. Good linearity was observed for 92% of the analytes in the concentration range of 2–250 μg L−1 for all seven of the chrysanthemum samples. The LODs of the 112 pesticides ranged from 0.01 to 31.41 μg L−1, depending on the sample, while the mean recoveries of all of the spiked pesticides ranged from 81.8% to 102% for concentrations of 20, 50, and 200 μg kg−1. These results clearly demonstrate the applicability of the developed method for the simultaneous determination of multi-pesticides in various chrysanthemum samples.

Demonstration of Photodynamic Molecules as Larvicides towards the Yellow Fever Mosquito Aedes aegypti

Each year, mosquitoes serve as a vector to transmit diseases that kill upwards of 750,000 people. Although the need for vector control of these organisms is clear, the misuse of modern pesticides has caused significant ecological damage as well as the development of pesticide‐resistant mosquitoes. Photosensitive insecticide technology has shown potential to minimize ecological damage by targeting classically resistant mosquitoes in new ways. These photoactive molecules, specifically safranin‐O (Saf‐O) and methylene blue (MB), transfer their energy to molecular oxygen to form reactive oxygen species (ROS). These species damage biological systems in the mosquito that differ from the systems excessively targeted by modern pesticides. By targeting new and less resistant biological systems, photosensitive insecticides present a novel strategy for vector control. Currently the literature lacks the in vivo pathway describing ROS generation by photodynamic insecticides. Here we show the generation of ROS in vivo using Saf‐O and MB along with a model of the photodynamic interaction with the Aedes aegypti larva.Support or Funding InformationThe authors would like to thank the Kenyon College Summer Scholars Program for the funding received to pursue this project.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Do field-level practices of Cambodian farmers prompt a pesticide lock-in?

Agronomic practices such as fertilizer application or seed rates have been known to affect rice pests and damage, but the evidence is often blurred in studies on pest management decisions and invisible in studies on pesticide lock-in. Combined agronomic practices and pesticide use may create technological lock-in, occurring when the combination has accumulated advantages over time which encourages its continued use, even if better options are available. We present results from a survey among farmers (N = 400) from five provinces in Cambodia. We asked about field-level, agronomic practices and applied a regression analysis to determine whether these practices affect pesticide application. Farmers from the selected provinces produce rice intensively, particularly those in provinces in the Mekong Delta where a percentage of farmers would aim for three crops per year.Cambodian farmers in the five sampled provinces rely on pesticides for pest control with an average of 2–5 applications each for herbicide and insecticide, and 1–6 applications of fungicide per season. Farmers from the Mekong Delta, particularly Prey Veng Province, made more pesticide applications. Interestingly, of nine agronomic practices tested, six were found to significantly correlate with no applications as in organic management recommendations, as well as misuse of pesticides. Varied combinations of agronomic practices including seed rate, crop establishment method, seed treatment, cultivating larger landholdings, irrigation through gravity irrigation system, and number of fertilizer applications predicted herbicide, insecticide and fungicide application. Interactions varied across wet and dry season. Pesticide use makes sense to farmers given a specific combination of agronomic practices. Therefore we argue that field-level agronomic practices contribute to pesticide lock-in as much as wider innovation system conditions such as trade and regulation of pesticides.These findings imply that addressing the pesticide lock-in to facilitate a shift to more sustainable practices, such as Integrated Pest Management, should not only aim at broader innovation systems or industry level changes. There are adjustments and fine-tuning of agronomic practices that also need to be made to wean farmers from pesticide reliance.

Do farmers misuse pesticides in crop production in China? Evidence from a farm household survey.

In China, pesticide overuse and underuse have been studied. However, little empirical evidence has been provided for pesticide misuse. Using data from a farm household survey in 2016, we quantitatively analyzed Chinese farmers' pesticide misuse in the production of rice, apple, tea, and greenhouse vegetables. The results show that pesticide misuse is common in China. However, the misuse is found to be lower in rice production than in the production of apple, tea, and greenhouse vegetables. Compared with that of the major pests, pesticide misuse is much more common for the control of the secondary pests. In a considerable number of observations, some farmers even failed to indicate the pests they controlled or the pesticides they used. Pesticide misuse may result in both the overuse and underuse of pesticides. In China, pesticide misuse could be attributed to the lack of pest management knowledge among farmers, limited accessibility to a high-quality governmental agricultural extension service, misleading information, and absence of pest prediction and forecast. Hence, a socialized agricultural extension system and new agricultural extension models adapted to different farmers are expected to be developed and implemented in China. © 2019 Society of Chemical Industry.

Pesticide Use Practices in Root, Tuber, and Banana Crops by Smallholder Farmers in Rwanda and Burundi.

Misuse and poor handling of chemical pesticides in agriculture is hazardous to the health of farmers, consumers, and to the environment. We studied the pest and disease management practices and the type of pesticides used in four root, tuber, and banana (RTB) crops in Rwanda and Burundi through in-depth interviews with a total of 811 smallholder farmers. No chemical pesticides were used in banana in either Rwanda and Burundi, whereas the use of insecticides and fungicides in potato was quite frequent. Nearly all insecticides and about one third of the fungicides used are moderately hazardous. Personal protective equipment was used by less than a half of the interviewed farmers in both countries. Reported cases of death due to self- or accidental-poisoning among humans and domestic animals in the previous 12 months were substantial in both countries. Training of farmers and agrochemical retailers in safe use of pesticide and handling and, use of integrated pest management approaches to reduce pest and disease damage is recommended.

Potentials of termite mound soil bacteria in ecosystem engineering for sustainable agriculture

The environmental deteriorating effects arising from the misuse of pesticides and chemical fertilizers in agriculture has resulted in the pursuit of eco-friendly means of producing agricultural produce without compromising the safety of the environment. Thus, the purpose of this review is to assess the potential of bacteria in termite mound soil to serve as biofertilizer and biocontrol as a promising tool for sustainable agriculture. This review has been divided into four main sections: termite and termite mound soils, bacterial composition in termite mound soil, the role of bacteria in termite mound soil as biofertilizers, and the role of bacteria in termite mound soil as biocontrol. Some bacteria in termite mound soils have been isolated and characterized by various means, and these bacteria could improve the fertility of the soil and suppress soil borne plant pathogens through the production of antibiotics, nutrient fixation, and other means. These bacteria in termite mound soils could serve as a remarkable means of reducing the reliance on the usage of chemical fertilizers and pesticides in farming, thereby increasing crop yield.

The impact of wipe sampling variables on method performance associated with indoor pesticide misuse and highly contaminated areas

Pesticide misuse incidents in residential indoor areas are typically associated with misapplications that are inconsistent with the label directions of the product. Surface wipe sampling and analysis procedures are relied upon to evaluate the extent of indoor contamination and the remediation efforts successfully. In general, surface wipe sampling procedures are widely varied, which can complicate the comparison of the results and data interpretation. Wipe sampling parameters were studied for the insecticides malathion and carbaryl. The parameters evaluated include wipe media, wetting solvents, composite sampling, surface concentration, and the influence of differing product formulations. Porous and nonporous surfaces tested include vinyl tile, plywood and painted drywall (porous/permeable) and stainless steel and glass (nonporous/impermeable). Specific wipe materials included pre-packaged sterile-cotton gauze, pre-cleaned cotton twill, cotton balls, and a pre-packaged, pre-wetted wipe. Commercially available insecticide formulations were tested, and the results were compared to surfaces fortified with neat analytes to determine surface recovery results (efficiency). A sampling procedure to measure pesticide residues was developed, and variables associated with the sampling methods were evaluated to clarify how estimations of surface residues are impacted. Malathion recoveries were 73–86% for twill and pre-wetted, pre-packaged isopropanol wipes on nonporous materials. Malathion formulations ranged from 78 to 124% for pre-wetted, pre-packaged isopropanol wipes and cotton gauze wipes on nonporous materials. Carbaryl and carbaryl formulation recoveries were 82–115% and 77–110%, respectively, on nonporous surfaces for all tested wipe materials. While not every wipe sampling variable could be tested, the collected information from this study may be useful and applied to sampling plans for classes of chemicals with similar physicochemical properties.

Rational Integration of Biomineralization, Microbial Surface Display, and Carbon Nanocomposites: Ultrasensitive and Selective Biosensor for Traces of Pesticides

AbstractNowadays, the over misuse of organophosphate pesticides (OPP) has seriously threatened human health and environment, and it is challenging and indispensable to establish biosensor for supersensitive, reliable, and fast detection of traces of OPP in real samples. This work provides an interdisciplinary strategy for the construction of electrochemical OPP biosensor with supersensitivity, high selectivity, simple operation, and fast response. First, amino acid ionic liquid (AAIL) is used as stabilizer to dramatically improve the dispersibility of carbon nanotube (CNT) in the water phase, so that the obtained CNT@AAIL composites show good conductivity, biocompatibility, and electrocatalytic activity. Further, CNT@AAIL composites are employed to improve the conductivity and electrochemical activity of mineralized organophosphate hydrolase (OPH)‐fused cell (M‐Cell) with excellent catalytic activity for the fabrication of electrochemical biosensor. Based on synergistic effects of CNT@AAIL and M‐Cell, the constructed biosensor shows 2–8 orders of magnitude lower limit of detection (3 fmol L−1) than those of reported OPP analytic methods. In addition, due to the specificity of OPH and detection at negative potential, the biosensor shows excellent selectivity. In addition, the biosensor also demonstrates the acceptable reliability for the traces of pesticides in real samples. This work will open an interdisciplinary avenue for supersensitive electrochemical biosensor.

Can Organic Sources of Nutrients Increase Crop Yields to Meet Global Food Demand?

Meeting global demand of safe and healthy food for the ever-increasing population now and into the future is currently a crucial challenge. Increasing crop production by preserving environment and mitigating climate change should thus be the main goal of today’s agriculture. Conventional farming is characterized by use of high-yielding varieties, irrigation water, chemical fertilizers and synthetic pesticides to increase yields. However, due to either over- or misuse of chemical fertilizers or pesticides in many agro-ecosystems, such farming is often blamed for land degradation and environmental pollution and for adversely affecting the health of humans, plants, animals and aquatic ecosystems. Of all inputs required for increased agricultural production, nutrients are considered to be the most important ones. Organic farming, with use of organic sources of nutrients, is proposed as a sustainable strategy for producing safe, healthy and cheaper food and for restoring soil fertility and mitigating climate change. However, there are several myths and controversies surrounding the use of organic versus inorganic sources of nutrients. The objectives of this paper are: (i) to clarify some of the myths or misconceptions about organic versus inorganic sources of nutrients and (ii) to propose alternative solutions to increase on-farm biomass production for use as organic inputs for improving soil fertility and increasing crop yields. Common myths identified by this review include that organic materials/fertilizers can: (i) supply all required macro- and micro-nutrients for plants; (ii) improve physical, chemical and microbiological properties of soils; (iii) be applied universally on all soils; (iv) always produce quality products; (v) be cheaper and affordable; and (vi) build-up of large amount of soil organic matter. Other related myths are: “legumes can use entire amount of N2 fixed from atmosphere” and “bio-fertilizers increase nutrient content of soil.” Common myths regarding chemical fertilizers are that they: (i) are not easily available and affordable, (ii) degrade land, (iii) pollute environment and (iv) adversely affect health of humans, animals and agro-ecosystems. The review reveals that, except in some cases where higher yields (and higher profits) can be found from organic farming, their yields are generally 20–50% lower than that from conventional farming. The paper demonstrates that considering the current organic sources of nutrients in the developing countries, organic nutrients alone are not enough to increase crop yields to meet global food demand and that nutrients from inorganic and organic sources should preferably be applied at 75:25 ratio. The review identifies a new and alternative concept of Evergreen Agriculture (an extension of Agroforestry System), which has potential to supply organic nutrients in much higher amounts, improve on-farm soil fertility and meet nutrient demand of high-yielding crops, sequester carbon and mitigate greenhouse gas emissions, provide fodder for livestock and fuelwood for farmers and has potential to meet global food demand. Evergreen Agriculture has been widely adapted by tens of millions of farmers in several African countries and the review proposes for evaluation and scaling-up of such technology in Asian and Latin American countries too.

Distribution of agricultural pesticides in the freshwater environment of the Guayas river basin (Ecuador)

The rapid increase and transition to more intensive agricultural activities in developing nations are often leading to misuse and overuse of pesticides, making their environment vulnerable for pesticide accumulation. In the present study, the Guayas river basin was taken as a representative case study to evaluate pesticide contamination of the Ecuadorean freshwater environment. Pesticide contamination was determined at 181 sampling sites by a multi-residue method using solid phase extraction (SPE) and pesticide residues were linked with agricultural land use activities to identify the main pollution sources. Moreover, the biological water quality status based on macroinvertebrate communities was determined at every location and the relation with the occurrence of pesticide residues was further investigated. Results showed that pesticide contamination of the freshwater environment was widely present in the Guayas river basin with detections at 108 sampling sites (60%). A total of 26 pesticide products were identified. Most frequently detected pesticides included cadusafos (62 locations), butachlor (21 locations) and pendimethalin (21 locations), with concentrations up to 0.081, 2.006 and 0.557 μg·L−1 respectively. Pesticide residues detected in this study did not significantly influence the biological water quality (p = 0.69), but were observed to be positively correlated with ammonium concentrations, supporting the assumed combined application of chemical fertilizers and pesticides in agriculture. These pesticide residues were also associated with one or more agricultural crops, with in particular the banana and rice industries identified as major pollution sources. Both high consumption rates and non-specific application methods, such as aerial spraying of banana plantations and application directly into the water layer of irrigated rice fields, may attribute to pesticide contamination of the freshwater environment of the Guayas river basin. It is therefore suggested that measures, e.g. legal regulations and awareness campaigns, taken to prevent environmental pollution and accumulation of pesticides primarily focus on these industries.