Negative Effects Of Pesticides Research Articles

Realization of Nodulation and Nitrogen-Fixing Activities of Bradyrhizobium japonicum and Rhizosphere Microbiota through Seed Treatment with Pesticide Standak Top and Spraying Plants with Soybean Seed Lectin

The idea of the study was to use soybean lectin as a biologically active compound with a broad spectrum of action to spray soybean plants for stabilization of the formation and functioning of the soybean-rhizobium symbiosis as well as the nitrogen-fixing activity of rhizosphere microbiota against the background of seed treatment with chemical plant protection product Standak Top — an innovative pesticide with fungicidal and insecticidal activity for the control of major diseases and pests of soybean plants. Aim. To study the peculiarities of formation and functioning of soybean-rhizobium symbiosis as well as the nitrogen-fixing activity of rhizosphere microbiota under spraying plants with specific soybean seed lectin on the background of seed treatment with Standak Top and inoculation with nodule bacteria Bradyrhizobium japonicum 634b on the sowing day in the conditions of pot experiments with soil as a substrate. Methods. Physiological, microbiological, gas chromatography, and statistical methods were used. Results. It was shown that after seed treatment with Standak Top (1.5 L/ton of seeds) on the sowing day, there was observed suppression of the process of nodule formation on the roots in the period of soybean vegetative growth. The nitrogen-fixing activity of the symbiotic system was at the control level, while the functional activity of soil diazotrophs was suppressed (by 1.2—2.2 times). Spraying plants in the phase of two trifoliate leaves (V2) with soybean seed lectin (without pesticide) led to an increase in the total mass of nodules on the plant (by 1.5 and 1.9 times as well as by 2.3 and 2.0 times compared to the control of inoculation in the phase of three trifoliate leaves (V3) and beginning of pod formation (R3), respectively). The increase in the total mass of the symbiotic apparatus on soybean roots in the phases V3 and R3 respectively was by 1.4 and 1.5 times in comparison with seed treatment with Standak Top, and the mass of one nodule was higher by 1.3 and 1.6 times, respectively. Soybean seed lectin led to a signifi cant increase in the actual nitrogenase activity of the soybean-rhizobium symbiosis. It was 2.9 and 1.9 times higher compared to control of inoculation and 2.1 and 1.8 times compared to the variant of inoculation + pesticide in the V3 and R3 phases, respectively. The functional activity of soil nitrogen-fixing microorganisms did not change significantly. The use of soybean seed lectin against the background of the seed treatment with Standak Top and inoculation contributed to the stabilization and increase in the rhizobia nodulation ability, the suppression of which was due to the infl uence of such an anthropogenic factor as pesticides. Th ere was observed an increase in the number (by 1.6 and 1.2 times) and mass of root nodules (by 2.2 and 1.5 times and 1.4 and 1.2 times, respectively, compared to the controls of inoculation and inoculation + pesticide). Soybean seed lectin significantly increased the nitrogenase activity of the symbiosis against the background of Standak Top (by 1.9 and 1.6 times and 1.4 and 1.5 times, respectively, in the V3 and R3 phases of soybean ontogenesis) compared to the control of inoculation and inoculation + Standak Top. Conclusions. The obtained results suggest the possibility of using the method of spraying plants with specific lectin as a means of leveling (or mitigating) the negative effect of pesticides used for the seed treatment on the formation and functioning of the symbiosis and rhizosphere diazotrophic microbiota. This indicates the prospects of studying the biological activity of phytolectins in spraying plants in order to regulate the formation and functioning of phytobacterial systems, as well as their responses to various environmental or anthropogenic stress factors, in particular, to the effect of chemical plant-protecting products used for the seed treatment.

Habitat quality, urbanisation & pesticides influence bird abundance and richness in gardens

Gardens are regularly portrayed as green oases, refuges for wildlife that has been displaced from the countryside by intensive farming practices which have reduced habitat availability. Pesticides are also commonly used in urban areas, but few studies have investigated their impacts. In this study, we explored how bird richness and abundance in gardens across the UK are influenced by habitat quality, urbanisation level and pesticide practices. To achieve this, we collaborated with the British Trust for Ornithology (BTO) which runs Garden Birdwatch, a citizen-science-based garden bird recording scheme. Participants in the study were asked to complete a questionnaire about their pesticide practice. From the 615 gardens that provided useful data, we found that 32.2 % applied pesticides in their gardens and that glyphosate comprised 53.3 % of these applications. We found that bird abundance and species richness was lower in suburban compared to rural gardens but positively influenced by measures of garden quality and by surrounding habitat quality. We show that there was an interaction between the habitat quality of the surrounding area and pesticide use: negative effects of pesticides on species richness were more pronounced in gardens in areas of high habitat quality compared to those surrounded by poor habitat. We found that pesticide use, and particularly glyphosate and metaldehyde, negatively predicted the abundance of house sparrows, a fast-declining bird species. The average house sparrow abundance was 12.1 % lower in gardens applying any pesticide, 24.9 % lower with glyphosate, and 38.6 % lower with metaldehyde. Overall, our study shows that garden bird abundance and richness is strongly influenced by both extrinsic and intrinsic factors, and suggests that garden management, particularly regarding pesticide use, has a significant effect on bird life.

Identification of the Common Type of Pesticides Used by Bee Farmers from Selected Honey-Producing Areas in Tanzania: A Case of Kijiji Cha Nyuki Co. Ltd, Singida Region

Purpose: The main purpose of this study was to identify the common type of pesticides used by bee farmers. Specifically, the study presents preliminary findings of an inquiry that examined pesticides used by bee farmers and evaluates the awareness among farmers on the negative effects of pesticides in bee products from Kijiji cha Nyuki located in Tanzania.
 Methodology: A mixed methods approach was adopted for this study and collected data both primary and secondary data were collected using physical observation and survey, interviews, and questionnaires, purposive and random sampling techniques were used in this study to select a total of 104 participants who was taken as a sample from universal populations. Qualitative and quantitative data were analyzed using IBM Statistical Package for Social Sciences (SPSS) Computer Programme version 25, where the statistics aspect was determined from the results obtained from both questionnaires and laboratory experiments. A preliminary investigation from Africa’s most renewed bee village in Tanzania; collected samples were analyzed at TBS & SGS laboratories.
 Findings: Based on the findings from informants comprises of two forest officers and two district agricultural officers showed despite a variety of pesticides that can contaminate bee and honey products, the widely observed are Insecticides (cynahalotrine, chlorpyrifos, clothianid), Fungicides (boscalid), and Herbicide (pendimethohele, and cyfluthrin). To mitigate the challenge posed by these pesticides, farmers always work hard to comply with pesticide regulations NBPIS, NBP, 1998, Beekeeping Act No. 15/2002; Beekeeping Regulations, 2005; NBP 2001-2010 and GCBP 2007.
 Unique Contribution to the Theory and Policy: the study suggests that participants should be guided to produce the expected outcome, and it has to start with the issue of power. In terms of the policy implementation process, the way policy regulating pesticides and policies activities are communicated should set the right tone that will encourage collaboration to ensure all participants will fully contribute. So, by paying attention to the effect of power, the fundamental principles of openness and inclusiveness can be upheld during the policy design and implementation process. It also recommends further study that will examine the perceptions of decision-makers, consumers, beekeepers, and academicians about the extended use of pesticides in Tanzania, bearing in mind the health implication of the unauthorized use of pesticides.

Toxicological assessment of sublethal dose of acetamiprid in male mice and the efficacy of quercetin

Acetamiprid (ACP) is a neonicotinoid insecticide that is the most effective pesticide for crop protection as well as flea control in agricultural animals and pets in the world. The goal of this study was to look at the in vivo effects of a sublethal dose of ACP on hematotoxicity, oxidative stress, hepatotoxicity, nephrotoxicity, immunotoxicity, and histological alterations, as well as the role of quercetin (QE) in alleviating these effects. Twenty adult male mice were divided into four equal groups orally administered corn oil (control), QE (50 mg kg−1 b.wt.), ACP (1/10 LD50) or ACP plus QE for two weeks. The results showed that ACP significantly lowered the body weight gain, hematological indices, glutathione (GSH), and both cellular and humoral immunity, On the other hand, levels of lipid peroxidation (LPO), glutathione peroxidase (GPx), and liver and kidney marker values were considerably increased in male mice exposed to ACP. In addition, examination under light microscopic showed that ACP induces histological alterations in liver and kidney tissues. The results also revealed that treating intoxicated mice with QE significantly reduced the deleterious effects of ACP. In conclusion, current results show that ACP at the sub lethal dose poses toxic risks to the liver and kidneys, and QE as a natural material enhances antioxidant defenses, which can be used as a potential interventional therapy against negative effects of pesticides like ACP.

RISK ASSESSMENT AND PREDICTION OF THE POSSIBILITY OF ACUTE TOXIC EFFECTS ON WORKERS WHEN APPLYING OBERON RAPID 240 SC

the issue of uncontrolled pesticides application is quite acute in the system of state control over the use of chemical plant protection products and is of a global nature. Indeed, the dangerous effect of chemicals is a potential toxic effect on professional and non-professional contingents. Therefore, the study and forecasting of possible risks of negative effects of pesticides is an integral part of their implementation in the practical activities of agricultural and private farms. The aim was to predict the occurrence of acute toxic effects on workers involved in the treatment of crops with formulation based on the new insecticide spiromesifen and a representative of avermectins, abamectin. Materials and methods. To calculate the coefficients of possible inhalation poisoning, the physic-chemical properties and consumption rates of the studied active ingredients of the Oberon Rapid 240 SC formulation, the methodical approaches from State Standard 8.8.1.002-98 wase used, and to determine the possibility of acute toxic effects, taking into account the selectivity of their action, we used the Sergeev’s S.G. method, taking into account two ways of potential entry of chemicals into the body – inhalation and dermal. Results. According to the "Hygienic classification of pesticides by the degree of hazard", spiromesifen and abamectin, as well as formulation based on them, belong to the Ⅳth hazard class according to the coefficient of possible inhalation poisoning, which was less than 0.5. In terms of inhalation and dermal coefficients of selectivity of action, the studied compounds were classified as substances with a high selectivity of action, except for the value of the coefficient of inhalation action of abamectin, which was less than 100 and made it possible to classify the compound as substances with a relatively low selectivity of action. Conclusions. The obtained data indicate a low possibility of acute poisoning when using formulations based on insecticides – spiromesifene and abamectin, as well as their relative safety in the occurrence of acute toxic effects when inhaled and in contact with the skin.

Effects of pesticides and metals on penaeid shrimps in Maputo Bay, Mozambique – A field study

Estuaries are important nursery areas for many species and these habitats are often affected by anthropogenic activities. We investigate possible negative effects of pesticides and metals on penaeid shrimps in Maputo Bay, Mozambique. Shrimps and water samples were collected in three estuaries and one coastal area for biomarker and chemical analysis. Acetylcholinesterase (AChE) and glutathione-S transferase activities were analysed as biomarkers for pollutants. 37 different pesticides were analysed in water samples and shrimp muscle tissue was analysed for 10 metals. Risk assessment showed that the environmental thresholds were exceeded for several herbicides in three of four of the assessed nursery areas. Lower AChE activities were detected in shrimps captured close to an agriculture area and this location had the lowest shrimp densities. Metal analysis in shrimp showed low levels. Despite localized effects, results highlight the need to improve the regulation of pollutants in the Espírito Santo estuary in Maputo bay.

Quinoa Mitigates Chlorfenapyr-Induced Testicular Toxicity in Rats

Chlorfenapyr (Chf), belongs to a new chemical class calledhalogenated pyrroles, used extensively in Egypt. Negative effects of pesticides on the male reproductive system have been shown broadly. In recent years, the use of medicinal herbs in reducing pesticide toxicity has increased worldwide; one of these herbals is Quinoa seeds (QS), contains high amount of protein, vitamins, and minerals. Our study evaluated the effects of QS on testicular toxicity in rats exposed to Chf. Twenty rats were divided into four groups; group (I) as control was fed on basal diet only, group (II) QS at 30% from the basal diet, group (III) 180 mg/kg b.w/day of Chf, was fed on basal diet only and group (IV) Chf at 180 mg/kg b.w/day plus QS at 30% from the basal diet, the experimental period was four weeks. Rats were sacrificed and blood serum, sperm, and sexual organs samples were collected for biochemical and histomorphological studies. Results revealed that Chf treated animals showed sagging testicles with increased the testis relative weights. This effect was associated with a decline in count, motility, and viability of sperms, and increased sperm abnormality, and a decrease in sex hormones level (P<0.05). On the other hand, QS showed improvement in almost all estimated parameters and mitigated all the toxic effects of Chf, which was confirmed with the histological examination of the testis. So, we can encourage QS consumption as a clue for the toxicity and infertility problems revealed as a result of chlorfenapyr exposure.

Metabolomics unveils the influence of dietary phytochemicals on residual pesticide concentrations in honey bees

The losses of honey bee colonies and declines of other insect pollinators have been associated with negative effects of pesticides. Honey bees as well as other pollinators are nectar and pollen foragers and thus are exposed to an extensive range of phytochemicals. Understanding the synergistic, additive, and antagonistic effects of plant secondary metabolites and pesticides in honey bees may help to protect honey bee colonies against agrochemicals. In this study, we used untargeted metabolomics to investigate the impact of dietary phytochemical composition on the residual concentration of three pesticides: imidacloprid, tau-fluvalinate and tebuconazole in exposed honey bees. Honey bees were given different diets based on pollen or nectar from four plants: Reseda odorata, Borago officinalis, Phacelia tanacetifolia, and Trifolium repens for two days. Thereafter, they were orally exposed to 10 ng/bee imidacloprid or contact-exposed to 0.9 μg/bee tau-fluvalinate or 5 μg/bee tebuconazole. After 1 h of oral exposure or 24 h of contact exposure, the honey bees were anaesthetised with CO2, sacrificed by freezing, extracted with a validated QuEChERS method, and residual pesticide concentrations were determined by LC-QTRAP-MS/MS. The phytochemical composition in the given diets were profiled with an UHPLC-Q Exactive-MS/MS. The results revealed that the dietary phytochemical composition has a noteworthy influence on the concentration of residual pesticides in honey bees. The correlation coefficient analysis demonstrated that flavonoids have a reducing effect on the residual concentration of imidacloprid and tau-fluvalinate in honey bees. The results also highlighted that exposure to imidacloprid impaired the metabolism of sugars in honey bees. Exploiting flavonoid-rich plants may protect honey bees against pesticides and hold promise as forage plants in future beekeeping.

Agrochemical pesticide production, trade, and hazard: Narrowing the information gap in Colombia

Pesticides are a major tool for the intensification of agriculture, and helped to increase food, feed and biofuel production. Yet, there are persistent concerns about the negative effects of pesticides in human health and the environment, particularly in low and middle income countries (LMICs). Given the lack of information on pesticide exposure and hazard, Colombia exemplifies the need to narrow the information gap on pesticide risk in LMICs. We assessed pesticide hazard in Colombia based on the official toxicity categorization, compared it to more integral international standards, and identified main actions to narrow this information gap. Results showed that Colombia has been a relevant regional actor in pesticide production and trade, reaching almost 75 million kilogrammes and liters sold in 2016. Based on acute toxicity for humans, a quarter of the amount of pesticides sales and imports, and a third of the exports in 2016 ranged from moderately to extremenly toxic. The top-selling agrochemicals in 2016 (glyphosate with 14% of the total sales, chlorpyrifos 7.5% and mancozeb 6.9%) are also commonly used in other countries, reflecting a homogenized global industry. Compared to integral international categorizations, we found that for that year 63% of the pesticides sold with slightly acute toxicity are actually considered highly hazardous pesticides (HHP) for humans or the environment, evidencing the need to use a more integral hazard categorization in the country. Narrowing the information gap in pesticide use and associated risks demands a transparent process of knowledge creation and sharing, including funtional information and monitoring systems. This should be part of an integral assessment and regulation that better defines HHP, their production and trade to reduce pesticide risk while informing a transition towards sustainable food systems.

The Effect of Pesticides on the Microbiome of Animals

In recent decades an increase in the use of pesticides to protect plants from pests, diseases and weeds has been observed. There are many studies on the effects of various pesticides on non-target organisms. This review aims to analyze and summarize published scientific data on the effects of pesticides on the animal microbiome. Pesticides can affect various parameters of the animal microbiome, such as the taxonomic composition of bacteria, bacterial biodiversity, and bacterial ratios and modify the microbiome of various organisms from insects to mammals. Pesticide induced changes in the microbiome reducing the animal’s immunity. The negative effects of pesticides could pose a global problem for pollinators. Another possible negative effect of pesticides is the impact of pesticides on the intestinal microbiota of bumblebees and bees that increase the body’s sensitivity to pathogenic microflora, which leads to the death of insects. In addition, pesticides can affect vitality, mating success and characteristics of offspring. The review considers methods for correcting of bee microbiome.

Comparative Analysis of Pesticide Use Determinants Among Smallholder Farmers From Costa Rica and Uganda.

Pesticides are used globally in agriculture and pose a threat to the health of farmers, communities, and the environment. Smallholder farmers in low- and middle-income countries have generally a low socio-economic status and educational level. Consequently, they are particularly vulnerable to negative impacts of pesticides on their health, yields, or land. In a Knowledge, Attitude, and Practices study, we compared the pest management practices between a market-oriented farming system in Zarcero County, Costa Rica, and a subsistence-based farming system in Wakiso District, Uganda. We conducted a cross-sectional survey among smallholder farmers from Costa Rica (n = 300) in 2016 and from Uganda (n = 302) in 2017. We enrolled conventional and organic farmers, but also farmers with mixed practices and non-applicators of any pest management strategy. We found that the majority of pesticides used in both case studies are classified as highly hazardous by the World Health Organization. While more than 90% of smallholder farmers from both countries were aware of the negative health effects of pesticide exposure, <11% in Costa Rica and <2% in Uganda reported using personal protective equipment every time they handled or applied pesticides. Hygiene and other safe use practices were not adopted by all farmers (<61%), especially among farmers applying more hazardous pesticides. Conventional farmers from Costa Rica (14%) and Uganda (19%) reported disposing pesticide residuals into rivers. Using a logistic regression we found that organic farmers were more likely to having been trained on safe pesticide use practices. Using a robust regression, we observed that smallholder household income was primarily driven by education and not directly by the use of synthetic pesticides. Our results suggest that negative effects of pesticides can be managed over the whole life cycle, from purchase, via storage and application to residual and waste management by fostering professionalization of farmers. We advise future safe use and handling interventions to consider the pesticide use-related socioeconomic and demographic findings highlighted in this paper.

Drivers of Adoption of Integrated Pest Management among Small-scale Vegetable Farmers in Lubumbashi, DR Congo

Integrated Pest Management techniques (IPM) have been promoted last decade throughout a large Urban and Periurban Horticulture project (UPH) for a sustainable vegetable production in Congolese cities. However, the drivers of adoption of IPM techniques have not been either studied or identified. Data collected between April and June 2016 throughout field survey from 246 vegetable farmers were analyzed using a logistic regression model to determine the factors influencing the adoption of IPM techniques among vegetable farmers. Results showed that there were no significant differences between gender and the willingness to use IPM (p>0.05). However, a high portion of female (46.6%) reported that they would like to test new IPM techniques without any hesitation. Membership to a farmer’s group (Association) and previous agricultural training influenced positively and significantly the IPM adoption (p= 0.000) and increased highly the probability of adopting IPM respectively 4.2 and 7.7 times. Further, results also highlighted that farmers who previously perceived negative effects of pesticides were likely 5.2 times predisposed (p<0.05) to adopt alternative methods of pest control. Findings will allow an increased understanding of the process of IPM adoption and will help provide policy guidance to promote IPM diffusion with a purpose of reducing pesticide issues among farmers.

Impact, recovery and carryover effect of Roundup® on predator recognition in common spiny loach, Lepidocephalichthys thermalis.

Understanding the negative impact of a variety of environmental contaminants on aquatic animals is essential to curb biodiversity loss and stop degradation of ecological functions. Excessive and unrestricted use of pesticides is the most serious threat to aquatic animals including amphibians and fishes. Among the known pesticides, glyphosate based formulations have been shown to have lethal effects on many aquatic organisms. However, negative effects of pesticides on crucial ecological interactions such as prey-predator interactions are relatively unknown from tropics. In many aquatic organisms, recognition of predators is based on odor signatures; and therefore any anthropogenic alteration in water chemistry has the potential to impair recognition and learning of predators. Through a series of behavioral experiments we evaluated the effect of glyphosate based herbicide (Roundup®) on the antipredator behavior of common spiny loach, Lepidocephalichthys thermalis to understand the effects of pesticide-exposure on recognition of conspecific alarm cues, and associative learning to avoid predation. We exposed common spiny loach (for 3 h or 15 days) to sub-lethal concentration (0.5 mg a.e./L) of Roundup® and subsequently with conspecific alarm cues, signaling the proximity of a predator. Unexposed prey fish showed a significant reduction in activity level in response to conspecific alarm cues. Whereas such alarm response was not observed in prey fish that were exposed to Roundup® either for 3 h or 15 days. Such lack of response could be associated with alteration of olfactory function in prey individuals. However, this inability to detect the conspecific alarm cues was found to be transient and exposed fish recovered within 2 days. In subsequent experiments, we showed that Roundup® deactivates the conspecific alarm cues thus making them unavailable for prey to evoke the response. Furthermore, Roundup® mediated degradation of conspecific alarm cues and diminished the associative learning necessary for detection of the invasive/unknown/novel predators. Overall, due to the worldwide occurrence of glyphosate in water bodies, glyphosate mediated behavioral suppression exposes the prey animals to a considerable risk of predation, both by native and non-native predators.

Problem of assessment of pesticides neurotoxicity for the development of organism

Introduction. The results of many independent studies indicate a potential hazard to human health after exposure to chemical agents, in particular pesticides. Pesticides are chemical compounds that are widely used in agriculture, forestry, industry and everyday life for the control of pests. Pesticides are one of the environmental pollutants. Despite of the precautionary sanitary and hygienic measures in use, there is an increase in the presence of pesticides in atmospheric air, indoor and outdoor air, also in the processing of agricultural land in the soil and reservoirs; there is a presence of residual amounts in food. All these factors contribute to the enter of these compounds in the human body, which in future may be one of the causes of various diseases of chemical etiology. The nervous system during of ontogeny is one of the most vulnerable to the influence of chemicals. According to epidemiological evidence suggests that exposure to chemicals, including pesticides on the body in the pre- and postnatal period may lead to such neurological disorders in children as autism spectrum disorders, attention deficit hyperactivity disorder, learning disabilities and emotional and behavioural problems. Epidemiological observations indicate the association of these compounds with the development of the nervous system in children, but it is difficult to identify. The main source of information on possible negative effects of pesticides is the results obtained in experiments on laboratory animals. OECD guideline 426 focuses on the study of the functional development of the nervous system under the influence of pesticides in the pre and postnatal period. The aim of the study – to learn modern sources of literature on the study of the relationship between the action of pesticides on the body of pregnant women and the development of the fetus. Conclusion. Determination of the potential danger of pesticides for the developing organism is a priority. Scientific publications on epidemiological data indicate the relationship of exposure of pesticides in the pre- and postnatal period to the emergence of neurological disorders in descendants.

Negative effects of pesticides under global warming can be counteracted by a higher degradation rate and thermal adaptation

Summary An alarming finding for biodiversity is that global warming and pesticides often interact synergistically. Yet, this synergism may not capture the full picture because two counteracting processes may reduce the higher impact of pesticides under warming: higher pesticide degradation in the environment and thermal adaptation of populations. We tested for the effects of warming and multiple pulses of the insecticide chlorpyrifos on life history and fitness‐related physiological traits in the damselfly Ischnura elegans. To assess whether thermal adaptation is able to mitigate the impact of the pesticide under future warming, we exposed replicated populations from a colder, high latitude and from a warmer, low latitude in a common garden rearing experiment at 20 and 24 °C (the respective mean summer water temperatures at both latitudes). At the higher temperature pesticide degradation was higher, leading to less accumulation after multiple pulses compared to the lower temperature. Accordingly, the pesticide caused less mortality and less oxidative damage at the higher temperature. This contradicts the general belief (based on studies that kept pesticide concentrations constant) of a higher impact of pesticides under warming. Furthermore, the reduction of the impact of the pesticide at the higher temperature was more pronounced in the warm‐adapted low‐latitude populations, indicating a counteracting role of thermal adaptation. Policy implications. Our findings provide proof‐of‐principle for two key insights that will allow improving ecological risk assessment of pesticides under global warming: (i) higher pesticide degradation in the environment under warming may temper the impact of multiple pesticide pulses; (ii) gradual thermal evolution may further reduce the impact of pesticides at high latitudes under global warming. This knowledge can be very important for policy makers to arrive at a more realistic forecasting of the impacts of chemical pollution and climate change interactions on organisms.

The Role of Ethanolic Extracts of Leaves and Roots of &amp;lt;i&amp;gt;Lantana camara&amp;lt;/i&amp;gt; (L.) in the Management of Pests of Okra &amp;lt;i&amp;gt;Abelmoschus esculentus&amp;lt;/i&amp;gt; (L.) Moench

The cultivation of many crops in Africa is negatively affected by a number of constraints, the most important of which is the incidence of pests and diseases. In many areas of the world, the most preferred option in the management of pests is the application of synthetic chemical pesticides. Due to the negative effects of pesticides on humans and the environment as a whole, efforts are being made to find alternatives for pest management. Ethanolic extracts of the leaves and roots of Lantana camara were tested against the major pests of okra, Abelmoschus esculentus. The plant extracts were compared with a standard chemical insecticide, Mektin (a.i 18 g/L abamectin) in a randomly complete block design with four treatments and three replications. Parameters studied included the major pests of the plant and the damage caused, leaf area, plant height as well as yield of okra. Cotton aphids, Aphis gossypii, the tobacco whitefly Bemisia tabaci and the cotton flea beetle, Podagrica puncticollis were the major pests encountered on okra plants. Aphis gossypii and B. tabaci populations were significantly lower on the L. camara-sprayed plots compared with the control plots. Similarly, P. puncticollis numbers were significantly smaller on the L. camara-sprayed plots than the control plots. There were no significant differences between the treatments and the control for plant height, leaf area and yield. The significant reduction in pests numbers on the L. camara-sprayed plots indicates its potential as an alternative to chemical insecticides, thereby reducing the reliance on chemical insecticides in the management of insect pests.

Pesticide risk behaviors and factors influencing pesticide use among farmers in Kuwait

The widespread overuse of pesticides in agriculture has generated increasing concerns about the negative effects of pesticides on human health and the environment. Understanding farmers' perceptions of risk of pesticides and the determinants of pesticide overuse is important to modifying their behavior towards reducing pesticide use. A survey of 250 randomly selected smallholder vegetable farmers in Kuwait was conducted to quantify the extent of pesticide use, their pesticide risk perceptions and factors influencing their pesticide use behaviors. The majority of the farmers perceived pesticides pose some risk to the environment (65%) and human health (70.5%), while younger farmers were more likely to perceive this risk than older farmers. When asked to rate how risky pesticides were regarding several aspects of human health and the environment on a scale of 1(not risky) to 5 (extremely risky), concern was highest for the health of applicators (x̅=4.28) and lowest for air quality (x̅=2.32). The risk perceptions of the farmers did not have a positive influence on their pesticide use practices. A total of 76 pesticide active ingredients were found in use, and 9% of these belong to the WHO toxicity class II (moderately hazardous). On average, farmers applied 12.8kg of active ingredients per hectare per year, and 58% of the farmers were found to have overused pesticides, with an average overuse rate of 2.5kg. Pesticide application frequency ranged from two times a month up to once a week, depending on the crop. A binary probit model reveals that farmers' inadequate knowledge of pesticides, the influence of pesticide retailers and lack of access to non-synthetic methods of pest control are positively associated with pesticide overuse, while the propensity to overuse decreases with higher levels of education, training in Integrated Pest Management (IPM) and the safe use and handling of pesticides, and access to extension support. Comprehensive intervention measures for reducing pesticide overuse and limit the health and environmental hazards caused by pesticides are provided in this paper.

Land Ownership and Use of Pesticides. Evidence from the Mekong Delta

Massive use of pesticides is one of the major environmental problems in developing countries. I analyse the correlation between land ownership and use of pesticides in the Mekong Delta. On the one hand, the negative effects of pesticides on the long-run soil productivity should discourage owners to use pesticides. On the other hand, these chemicals increase the productivity in the short-run, pushing farmers to increase their use. The results show that the first effect prevails (i.e. land owners are more prone to increase the quantity of pesticides used than land renters are) and that sensitising programmes on the harmfulness of chemicals have no apparent effect on the farmers’ choice to increase the quantity of pesticides used.

Negative effects of pesticides on wild bee communities can be buffered by landscape context.

Wild bee communities provide underappreciated but critical agricultural pollination services. Given predicted global shortages in pollination services, managing agroecosystems to support thriving wild bee communities is, therefore, central to ensuring sustainable food production. Benefits of natural (including semi-natural) habitat for wild bee abundance and diversity on farms are well documented. By contrast, few studies have examined toxicity of pesticides on wild bees, let alone effects of farm-level pesticide exposure on entire bee communities. Whether beneficial natural areas could mediate effects of harmful pesticides on wild bees is also unknown. Here, we assess the effect of conventional pesticide use on the wild bee community visiting apple (Malus domestica) within a gradient of percentage natural area in the landscape. Wild bee community abundance and species richness decreased linearly with increasing pesticide use in orchards one year after application; however, pesticide effects on wild bees were buffered by increasing proportion of natural habitat in the surrounding landscape. A significant contribution of fungicides to observed pesticide effects suggests deleterious properties of a class of pesticides that was, until recently, considered benign to bees. Our results demonstrate extended benefits of natural areas for wild pollinators and highlight the importance of considering the landscape context when weighing up the costs of pest management on crop pollination services.

Farmers Awareness Concerning Negative Effects of Pesticides on Environment in Jordan

The main goal of this study was to determine the levels of knowledge of the farmers on the effect of pesticides on environment in Valleys area, Jordan. This is achieved through realizing some secondary objectives such as identification of the farmers' socioeconomic characteristics and its relation to some of the study variables, their attitude towards the negative effects of pesticides on the environment, their knowledge level about pesticides effect and their sources of information about pesticides use, storage and disposal. The study covered valleys areas, and some 98 farmers were included as stratified random sample. The results revealed that the 5% farmers do not rely on agricultural extension but they seek information from other trustworthy sources. The farmers have a positive attitude towards learning about the negative effects of the pesticides on the environment. The study also showed that the most common method of pesticides application is spraying using axi-sprayers or portable sprayers. Strengthen the agricultural extension and increase its effectiveness, promote trust and communication between those who guiding and farmers. Also strengthen the link between agricultural research centers and guiding centers to identify the appropriate type of pesticide to combat, to achieve the best results with least damage. Farmers should be knowledgeable about the importance of continuous medical checking up of their workers and especially those dealing with the agricultural chemicals.