Impact of Legally Compliant Organic Pesticides on Natural Enemies (original) (raw)
Related papers
Chemosphere, 2012
The generalist predator Orius laevigatus (Fieber) (Hemiptera: Anthocoridae) is a key natural enemy of various arthropods in agricultural and natural ecosystems. Releases of this predator are frequently carried out, and it is included in the Integrated Pest Management (IPM) programs of several crops. The accurate assessment of the compatibility of various pesticides with predator activity is key for the success of this strategy. We assessed acute and sublethal toxicity of 14 pesticides on O. laevigatus adults under laboratory conditions. Pesticides commonly used in either conventional or organic farming were selected for the study, including six biopesticides, three synthetic insecticides, two sulfur compounds and three adjuvants. To assess the pesticides' residual persistence, the predator was exposed for 3 d to pesticide residues on tomato sprouts that had been treated 1 h, 7 d or 14 d prior to the assay. The percentage of mortality and the sublethal effects on predator reproductive capacity were summarized in a reduction coefficient (E x ) and the pesticides were classified according to the IOBC (International Organization for Biological Control) toxicity categories. The results showed that the pesticides greatly differed in their toxicity, both in terms of lethal and sub lethal effects, as well as in their persistence. In particular, abamectin was the most noxious and persistent, and was classified as harmful up to 14 d after the treatment, causing almost 100% mortality. Spinosad, emamectin, metaflumizone were moderately harmful until 7 d after the treatment, while the other pesticides were slightly harmful or harmless. The results, based on the combination of assessment of acute mortality, predator reproductive capacity pesticides residual and pesticides residual persistence, stress the need of using complementary bioassays (e.g. assessment of lethal and sublethal effects) to carefully select the pesticides to be used in IPM programs and appropriately time the pesticides application (as function of natural enemies present in crops) and potential releases of natural enemies like O. laevigatus.
Effect of Insecticides on Natural-Enemies
Insecticides [Working Title], 2021
Pesticides management options for control of invertebrate pests in many parts of the world. Despite an increase in the use of pesticides, crop losses due to pests have remained largely unchanged for 30–40 years. Beyond the target pests, broad-spectrum pesticides may affect non-target invertebrate species, including causing reductions in natural enemy population abundance and activity, and competition between pest species. Assays of invertebrates against weathered residues have shown the persistence of pesticides might play an important part in their negative impacts on natural enemies in the field. A potential outcome of frequent broad-spectrum pesticide use is the emergence of pests not controlled by the pesticides but benefiting from reduced mortality from natural enemies and competitive release, commonly known as secondary pests.
Impacts of Pesticides on Arthropod Biological Control Agents
Information about the side-effects of pesticides on biological control agents is an essential requirement of integrated pest management (IPM). Different methods to test the effects of pesticides on natural enemies have been used and new methods are being developed. In the past, evaluations were mostly based on individual level (lethal or sublethal) endpoints. Differences in the used methods and the measured endpoints make it difficult to compare the results. There is increasing emphasis on using standard methods to combine the lethal and sublethal effects to a total effect. Especially, population-level effects or demographic toxicology has been concluded as a better measure because of its ecological relevance and is the current centre of attention. Very recently, molecular and biochemical methods, primarily, have been developed for detecting potential damage to populations at early stages. But these types of responses (i.e. biomarkers) to toxic stress are only demographically relevant if the response can be linked to effects at higher organism levels. We describe the methods used to study the effects of pesticides on beneficial arthropods and the current status of the evaluation of side-effects. We also provide new suggestions. In addition to methodological discussion, in the last part we presented a table containing summary database on the effect of key classes of commonly used pesticides on various natural enemies. This data may be helpful for researchers or IPM users.
Impact and Selectivity of Insecticides to Predators and Parasitoids
EntomoBrasilis, 2010
Problems with the use of insecticides has brought losses, such as, negative impact on natural enemies. When these beneficial insects reduce cause the eruption of pests and resurgence it’s more common. Thus principles of conservation these arthropods are extremely important in the biological natural control of pests, so that these enemies may present a high performance. Because of the negative impacts caused by insecticides on agriculture and their harmful effects on natural enemies, the objective of this article is to approach two important subjects, divided into three parts. Part I relates to the description of the main crop pests and their natural enemies; Part II involves the impact of insecticides on predators and parasitoids and Part III focuses on the selectivity of several groups of insecticides to natural enemies. Before spraying insecticides, it is necessary to choose a product that is efficient to pests and selective to natural enemies. So, it is indispensable to identify ...
Is the Naturally Derived Insecticide Spinosad® Compatible with Insect Natural Enemies
Biocontrol Science and Technology, 2003
Spinosad † (Dow Agrosciences) is a neurotoxic insecticide produced by fermentation of an actinomycete. Spinosad is classified as an environmentally and toxicologically reduced risk material and has been embraced by IPM practitioners as a biorational pesticide. We examined the available information on the impact of spinosad on natural enemies and classified mortality responses to spinosad using the IOBC laboratory and field scales that run from 1 (harmless) to 4 (harmful). In total, there were 228 observations on 52 species of natural enemies, of which 162 involved predators (27 species) and 66 involved parasitoids (25 species). Overall, 71% (42/ 59) of laboratory studies and 79% (81/103) of field-type studies on predators gave a class 1 result (not harmful). Hymenopteran parasitoids are significantly more susceptible to spinosad than predatory insects with 78% (35/45) of laboratory studies and 86% (18/21) of field-type studies returning a moderately harmful or harmful result. Predators generally suffer insignificant sub-lethal effects following exposure to spinosad, whereas parasitoids often show sub-lethal effects including loss of reproductive capacity, reduced longevity, etc. All studies agree that spinosad residues degrade quickly in the field, with little residual toxicity at 3 Á/7 days postapplication. We also examined the importance of route of exposure, species-specific and stagespecific susceptibility and we make recommendations for future studies. We conclude that for conservation of predator populations, spinosad represents one of the most judicious insecticides available but the use of this product should be evaluated carefully in situations where conservation of parasitoid populations is of prime concern.
Toxic Effects of Spinosad on Predatory Insects
Biological Control, 2002
Spinosad (Dow AgroSciences) is a mixture of tetracyclic-macrolide compounds produced by a soil actinomycete and has been classified as a bioinsecticide. Spinosad is highly active against Lepidoptera but is reported to be practically nontoxic to insect natural enemies. We assessed the impact of Spinosad in a granular maize-flour formulation on a selection of insect predators over periods of 2-14 days. In all cases, the quantities of Spinosad used were less than the maximum recommended rates given on the product label. Adults of Aleochara bilineata Gyllenhal (Coleoptera: Staphylinidae) suffered a high prevalence of mortality following consumption of 1000 or 2000 ppm Spinosad active ingredient (a.i.), but little mortality at 200 ppm. Larvae of Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae) did not consume the granular formulation and suffered little overall mortality. After 14 days of exposure, the earwig, Doru taeniatum (Dohrn) (Dermaptera:Forficulidae), suffered 48% mortality in the 1.2 ppm Spinosad treatment increasing to 98% in the 1200 ppm Spinosad treatment compared to 20% in controls. Earwigs suffered 86% mortality/intoxication 72 h after feeding on Spinosad-contaminated Spodoptera frugiperda J. E. Smith (Lepidoptera:Noctuidae) larvae. A field trial was performed to compare applications of commercial granular chlorpyrifos and Spinosad in maize-flour granules (200 and 2000 ppm a.i.; 4.8 -48 g a.i./ha, respectively) or as an aqueous spray (160 ppm a.i.; 48 g a.i./ha) on earwigs held inside gauze bags. Mortality of earwigs on control plants was less than 15% at 2 days postapplication compared to 33% on plants treated with granular chlorpyrifos, 83% on plants sprayed with 160 ppm Spinosad, and 91-95% on plants treated with 200 -2000 ppm Spinosad granules, respectively. Further mortality in the 24-h period postsampling ranged from <5% in control treatments, to 9% in the chlorpyrifos treatment, and to 55-65% in the Spinosad spray and granule treatments. We conclude that Spinosad cannot be considered to have an environmental safety profile similar to most established biological insecticides. © 2002 Elsevier Science
Journal of Economic Entomology, 2009
Experiments were conducted to evaluate the toxicity, feeding preference, repellency, and Þeld efÞcacy associated with the organic insecticides azadirachtin, pyrethrins, and spinosad against two stink bug species, Acrosternum hilare (Say) and Euschistus servus (Say) (Hemiptera: Pentatomidae). Laboratory toxicity bioassays were conducted using treated green bean pods. The conventional pyrethroid-cyhalothrin was included for comparison. A. hilare adults and nymphs were most susceptible to-cyhalothrin and to tank mixes of pyrethrins ϩ spinosad. E. servus adults were susceptible to-cyhalothrin, spinosad, and all tank mixes, whereas E. servus nymphs were susceptible to-cyhalothrin only. Feeding preference tests were conducted using insecticide-treated tomatoes and counting the number of feeding stylet sheaths on fruit after 24 h. All tomatoes treated with either azadirachtin, pyrethrins, or tank mixes resulted in fewer numbers of stylet sheaths than the untreated control, whereas treatment with spinosad alone did not. In Þlter paper repellency tests, both E. servus and A. hilare were repelled by pyrethrins and exhibited no response to azadirachtin. E. servus was attracted to spinosad in comparison with a water-treated control; however, A. hilare displayed no response. In Þeld efÞcacy trials, each of the organic insecticides reduced the number of stink bugs in soybean, Glycine max (L.) Merr., for up to 2 d after treatment; however, none of the insecticides reduced stink bug damage to fruit in tomatoes even after multiple applications. Implications for organic growers and integrated pest management programs are discussed.