Acute toxicity effects of pesticides on beneficial organisms - Dispelling myths for a more sustainable use of chemicals in agricultural environments.

Agricultural practitioners, researchers and policymakers are increasingly advocating for integrated pest management (IPM) to reduce pesticide use while preserving crop productivity and profitability. Using selective pesticides, putatively designed to act on pests while minimising impacts on off-target organisms, is one such option - yet evidence of whether these chemicals control pests without adversely affecting natural enemies and other beneficial species (henceforth beneficials) remains scarce. At present, the selection of pesticides compatible with IPM often considers a single (or a limited number of) widely distributed beneficial species, without considering undesired effects on co-occurring beneficials. In this study, we conducted standardised laboratory bioassays to assess the acute toxicity effects of 20 chemicals on 15 beneficial species at multiple exposure timepoints, with the specific aims to: (1) identify common and diverging patterns in acute toxicity responses of tested beneficials; (2) determine if the effect of pesticides on beetles, wasps and mites is consistent across species within these groups; and (3) assess the impact of mortality assessment timepoints on International Organisation for Biological Control (IOBC) toxicity classifications. Our work demonstrates that in most cases, chemical toxicities cannot be generalised across a range of beneficial insects and mites providing biological control, a finding that was found even when comparing impacts among closely related species of beetles, wasps and mites. Additionally, we show that toxicity impacts increase with exposure length, pointing to limitations of IOBC protocols. This work challenges the notion that chemical toxicities can be adequately tested on a limited number of 'representative' species; instead, it highlights the need for careful consideration and testing on a range of regionally and seasonally relevant beneficial species.

From field to table: Ensuring food safety by reducing pesticide residues in food.

The present review addresses the significance of lowering pesticide residue levels in food items because of their harmful impacts on human health, wildlife populations, and the environment. It draws attention to the possible health risks-acute and chronic poisoning, cancer, unfavorable effects on reproduction, and harm to the brain or immunological systems-that come with pesticide exposure. Numerous traditional and cutting-edge methods, such as washing, blanching, peeling, thermal treatments, alkaline electrolyzed water washing, cold plasma, ultrasonic cleaning, ozone treatment, and enzymatic treatment, have been proposed to reduce pesticide residues in food products. It highlights the necessity of a paradigm change in crop protection and agri-food production on a global scale. It offers opportunities to guarantee food safety through the mitigation of pesticide residues in food. The review concludes that the first step in reducing worries about the negative effects of pesticides is to implement regulatory measures to regulate their use. In order to lower the exposure to dietary pesticides, the present review also emphasizes the significance of precision agricultural practices and integrated pest management techniques. The advanced approaches covered in this review present viable options along with traditional methods and possess the potential to lower pesticide residues in food items without sacrificing quality. It can be concluded from the present review that a paradigm shift towards sustainable agriculture and food production is essential to minimize pesticide residues in food, safeguarding human health, wildlife populations, and the environment. Furthermore, there is a need to refine the conventional methods of pesticide removal from food items along with the development of modern techniques.

DsRNA-based pesticides: Considerations for efficiency and risk assessment.

In view of the ongoing climate change and the ever-growing world population, novel agricultural solutions are required to ensure sustainable food supply. Microbials, natural substances, semiochemicals and double stranded RNAs (dsRNAs) are all considered potential low risk pesticides. DsRNAs function at the molecular level, targeting specific regions of specific genes of specific organisms, provided that they share a minimal sequence complementarity of approximately 20 nucleotides. Thus, dsRNAs may offer a great alternative to conventional chemicals in environmentally friendly pest control strategies. Any low-risk pesticide needs to be efficient and exhibit low toxicological potential and low environmental persistence. Having said that, in the current review, the mode of dsRNA action is explored and the parameters that need to be taken into consideration for the development of efficient dsRNA-based pesticides are highlighted. Moreover, since dsRNAs mode of action differs from those of synthetic pesticides, custom-made risk assessment schemes may be required and thus, critical issues related to the risk assessment of dsRNA pesticides are discussed here.

Pest Status, Bio-Ecology, and Area-Wide Management of Mirids in East Asia.

Mirids (Hemiptera: Heteroptera: Miridae) feed upon a wide variety of cultivated and wild plants and can be economically important crop pests. They have traditionally been perceived as innocuous herbivores in East Asia; however, population levels of various mirid species have dramatically increased over the past decades. High-profile pests such as Apolygus spp., Adelphocoris spp., and Lygus spp. are now widely distributed across the region, and their infestation pressure is associated with climate, agroecological conditions, and farming practices. This review outlines how an in-depth understanding of pest biology, a systems-level characterization of pest ecology, and a comprehensive evaluation of integrated pest management tactics have enabled sustainable management of mirids across crop boundaries and harvest cycles. This work underscores how more holistic, integrative research approaches can accelerate the implementation of area-wide management of generalist pests, effectively prevent pest population build-up and yield impact, and shrink the environmental footprint of agriculture. In addition to highlighting the merits of interdisciplinary systems approaches, we discuss prospects and challenges for the sustainable management of polyphagous mirid pests in landscape matrices.

Bemisia tabaci MEAM1 still remains the dominant species in open field crops in Brazil / Bemisia tabaci MEAM1 ainda é a espécie dominante em cultivos a céu aberto no Brasil

Among Bemisia tabaci species, the invasive MEAM1 and MED species are key agricultural pests for many crops. In Brazil, most part of B. tabaci population outbreaks were associated with MEAM1, which, since 1990s quickly spread across the entire country. Later in 2014, the MED was identified in Brazil, initially more restricted to greenhouses, but suddenly reaching new areas in the South and Southeast open regions. Thus, our objective was to investigate the geographical distribution of MEAM1 and MED on open field crops in Brazil. MEAM1 is still the predominant species on open field crops such as soybean, cotton, and tomato. The sequencing of a cytochrome c oxidase subunit I (COI) gene fragment revealed a single haplotype of MEAM1, suggesting the establishment of a single MEAM1 strain in the country. The haplotypes found for MEAM1 and MED are genetically related to the globally dispersed strains, Jap1 and Mch1, respectively. Continuous monitoring of B. tabaci species is crucial because landscape alterations, climatic changes, and pest management methods may shift the B. tabaci species distribution and dominance in Brazilian crop areas.

Dentre as espécies de Bemisia tabaci, as espécies invasoras MEAM1 e MED se destacam como pragas de grande importância para várias culturas. No Brasil, a maior parte dos surtos populacionais de mosca-branca são associados a presença da espécie MEAM1, que a partir 1990 se espalhou por todo o país. Por outro lado, em 2014 a espécie MED foi identificada no Brasil, inicialmente restrita a casas de vegetação, mas rapidamente se difundindo em novas áreas nas regiões Sul e Sudeste do Brasil. Assim, nosso objetivo foi investigar a distribuição geográfica das espécies MEAM1 e MED em grandes culturas no Brasil. A espécie MEAM1 continua sendo predominante nas monoculturas como algodão, soja e tomate. O sequenciamento de um fragmento do gene citocromo c oxidase subunidade I (COI) revelou a presença de um haplótipo para MEAM1, sugerindo o estabelecimento de apenas uma linhagem no país. Os haplótipos encontrados para MEAM1 e MED são geneticamente relacionados as linhagens globalmente dispersas Jap1 e Mch1, respectivamente. O monitoramento contínuo das espécies de B. tabaci é crucial pois as mudanças na paisagem, mudanças climáticas e métodos de manejo das pragas podem alterar a dominância e a distribuição dessas espécies nas áreas agrícolas do Brasil.

Characterization of the Bipolaris maydis: symptoms and pathogenicity in popcorn genotypes (Zea mays L. ) / Caracterização de Bipolaris maydis: sintomas e patogenicidade em genótipos de milho-pipoca (Zea mays L. )

Southern corn leaf blight (SCLB) is one of the most important corn leaf diseases. Appropriate management strategies and the use of resistant cultivars allow disease control. Therefore, knowing the aspects related to the pathogen and the response of hosts makes it possible to design efficient strategies for selecting genotypes resistant to this disease. In this sense, the objective was to carry out the Bipolaris maydis isolate characterization, evaluating the pathogenicity in different popcorn lines and the symptoms generated in the host after inoculation. The isolate characterization consisted of the macromorphological evaluation of the colonies and the micromorphological evaluation of the conidia in the PDA medium. An experiment was carried out in a greenhouse to evaluate the pathogenicity of the isolate, using 20 inbred lines of popcorn in a randomized block design with four replicates. Inoculation was carried out by spraying leaves, with a suspension containing 1.0 x 104 conidia.ml-1 of the CF/UENF 501 isolate of B. maydis. An incidence assessment and three assessments of disease symptom severity were performed, with seven days intervals between evaluations. The morphological characterization data of the isolate were analyzed using descriptive statistics, and for disease severity, the linear regression model was applied the first-degree model. The variance analysis was performed for the linear and angular coefficients obtained for each treatment. When a difference was found, the Scott-Knott clustering algorithm at 5% significance was applied. The isolate had gray-green colonies, a cottony appearance, and an irregular shape. The lines L353, L354, and L624 show more resistance at the beginning and throughout the evaluations. The high virulence of the CF/UENF 501 isolate made it possible to differentiate the lines in terms of disease intensity and the pattern of symptoms presented.

Mancha-de-Bipolaris é uma das mais importantes doenças foliares do milho. Estratégias de manejo adequadas e o uso de cultivar resistente permitem o controle da doença, mas para tanto, conhecer os aspectos associados ao patógeno e a resposta do hospedeiro é necessário para traçar estratégias eficientes para seleção de genótipos resistentes a essa doença. Neste sentido, objetivou-se realizar a caracterização do isolado de Bipolaris maydis avaliando a patogenicidade em diferentes linhagens de milho-pipoca e os sintomas gerados no hospedeiro a partir da inoculação. A caracterização do isolado consistiu na avaliação macromorfológica das colônias e micromofológica dos conídios em meio nutritivo BDA. Para avaliação da patogenicidade do isolado foi conduzido um experimento em casa de vegetação utilizando 20 linhagens endogâmicas de milho-pipoca, com delineamento em blocos casualizados, com quatro repetições. A inoculação foi realizada por meio de pulverização em folhas, com uma suspensão contendo 1,0 x 104 conídios.ml-1 do isolado CF/UENF 501 de B. maydis. Foi realizada uma avaliação de incidência e três avaliações de severidade dos sintomas da doença, com o intervalo de sete dias para cada avaliação. Os dados da caracterização morfológica do isolado foram analisados por meio da estatística descritiva e para severidade da doença foi aplicado o modelo de regressão linear de primeiro grau. Realizou-se a análise de variância para o coeficiente linear e angular obtido para cada tratamento e quando constatada diferença aplicou-se o agrupamento de médias de Scott-knott a 5% de significância. O isolado apresentou colônias com coloração cinza esverdeado, aspecto algodonoso e forma irregular. As linhagens L353 e L354 e L624 estão entre as linhagens que apresentaram maior resistência no inicio e ao longo das avaliações. A elevada virulência do isolado CF/UENF 501 possibilitou diferenciar as linhagens quanto a intensidade da doença, bem como o padrão dos sintomas apresentados.

Health risks of pest control and disinfection workers after the COVID-19 outbreak in South Korea.

The exposure patterns of pest control and disinfection workers have changed after the coronavirus disease 2019 (COVID-19) outbreak, but the health risks of chemical exposure have not been assessed. We identified these workers' chemical exposure patterns and risks before and after the COVID-19 outbreak. We used data conducted between 2018 (pre-pandemic) and 2021 (post-pandemic) from three-year cross-sectional surveys on pest control and disinfection workers. Inhalation and dermal exposure concentrations were estimated using equations based on a biocidal product risk assessment model from the Korean National Institute of Environmental Research. The non-carcinogenic and carcinogenic risks of chemicals were calculated using the United States Environmental Protection Agency risk assessment model. We found that the annual work frequency (50th percentile) of foggers using disinfectants increased the most among all the work types, from 140 uses/year to 176 uses/year after the COVID-19 outbreak. Moreover, all chemicals' non-carcinogenic and carcinogenic risks increased regardless of exposure routes. In the worst scenario (95th percentile), the margin of exposure for citric acid, benzethonium chloride, benzyl-C12-16-alkyldimethyl chlorides, and sodium chlorite of inhalation exposure, and isopropyl alcohol and benzyl-C12-16-alkyldimethyl chlorides of dermal exposure were acceptable (>100) before the COVID-19 outbreak but became unacceptable (<100) after the COVID-19 outbreak. Carcinogenic risks of dichlorvos from inhalation and dermal exposure were above acceptable levels (>10-6) before and after the COVID-19 outbreak but comparatively high after the COVID-19 outbreak. Additionally, significantly more workers experienced health symptoms after the COVID-19 outbreak (p<0.05), with the most common being muscle lethargy (31%), skin/face stinging (28.7%), and breath shortness/neck pain (24.1%).

Eco-friendly approaches of zinc oxide and silver nitrate nanoparticles along with plant extracts against Spodoptera litura (Fabricius) under laboratory conditions.

The tobacco cutworm (Spodoptera litura) is a widespread pest that inflicts severe damage on various crops, including cotton, tobacco, and vegetables, with a particular preference for solanaceous plants. Traditional control methods often rely heavily on synthetic insecticides, leading to adverse effects on the environment, human health, and the development of insecticide resistance. In light of these challenges, this study explores the potential of nanotechnology as an innovative and sustainable approach to combat this notorious pest. Bioassays were conducted using laboratory-reared 3rd instar S. litura larvae. Eight different plant extracts coated with zinc oxide and silver nitrate nanoparticles were tested, with concentrations in both distilled water and ethanol at 3, 5, and 7 ml. Data were collected at 24, 48, and 72-h intervals. The results revealed that the highest larval mortality, reaching 98%, was observed in the group treated with silver nitrate nanoparticles derived from Cymbopogon citratus. In comparison, the group treated with zinc oxide nanoparticles dissolved in ethanol exhibited a larval mortality rate of 90%. Ethanol is a polar solvent that is widely used in the synthesis of nanocomposites. It is capable of forming strong hydrogen bonds with oxygen atoms, making it a good dispersant for zinc oxide nanoparticles. Additionally, ethanol has a low boiling point and a non-toxic nature, which makes it a safe and effective option for the dispersion of nanoparticles. Notably, the study concluded that silver nanoparticles combined with ethanol exhibited prolonged and more potent toxic effects against S. litura when compared to zinc oxide nanoparticles. Overall, this research underscores the potential of nanotechnology as a valuable component of Integrated Pest Management (IPM) strategies. By integrating nanotechnology into pest management practices, we can promote sustainable and environmentally friendly approaches that benefit both farmers and the ecosystem.

Plumeria alba flower extract-mediated synthesis of recyclable chitosan-coated cadmium nanoparticles for pest control and dye degradation.

In the current scenario, many synthetic chemicals have used long-term to control pests and mosquitoes, leading to the resistance of strains and toxicity effect on human beings. To overcome the adverse problem in recent advances, the scientific community is looking into nanofabricated pesticides and mosquitoes. This study aims to synthesize the recyclable chitosan-coated cadmium nanoparticles (Ch-CdNps) using Plumeria alba flower extract, which was further applied for insecticidal and mosquitocidal activities. The synthesized Ch-CdNps were confirmed by UV spectroscopy and FTIR analysis. The XRD, TEM, and DLS results confirmed the crystallinity with a spherical shape at 80-100 nm. The insecticidal activity proves that Ch-CdNps inhibited Helicoverpa armigera and Spodoptera litura at 100 ppm. In mosquitocidal, LC50 values of larvicidal of 1st instar were 4.116, 4.33, and 4.564 µg/mL, and the remaining three stages of instars, pupicidal, adulticidal, longevity, fecundity, and ovicidal assays inhibit the Anopheles stephensi followed by Aedes aegypti and Culex quinquefasciatus. Further, the first-order kinetics of photocatalytic degradation of methylene blue and methyl orange was confirmed. Based on the obtained results, Ch-CdNps can inhibit the pest, mosquitoes, and photocatalytic degradation.

Cadmium exposure through the food chain reduces the parasitic fitness of Chouioia cunea to Hyphantria cunea pupae: An ecotoxicological risk to pest control.

The toxicity of heavy metals on various trophic levels along the food chain has been extensively investigated, but no studies have focused on parasitic natural enemy insects. Herein, we constructed a food chain consisting of soil-Fraxinus mandshurica seedlings-Hyphantria cunea pupae-Chouioia cunea to analyze the effects of Cd exposure through food chain on the fitness of parasitic natural enemy insects and its corresponding mechanism. The results showed that the transfer of Cd between F. mandshurica leaves and H. cunea pupae and between H. cunea pupae and C. cunea was a bio-minimization effect. After parasitizing Cd-accumulated pupa, the number of offspring larvae, and the number, individual size (body weight, body length, abdomen length) and life span of offspring adults decreased significantly, while the duration of embryo development extended significantly. The contents of malondialdehyde and H2O2 in Cd-exposed offspring wasps increased significantly, accompanied by a significantly decrease in antioxidant capacity. The cellular immunity parameters significantly decreased in Cd-accumulated pupae, including the number of hemocytes, melanization activity and the expression level of cellular immunity genes (e.g. Hemolin-1 and PPO1). The humoral immunity disorder was found in the Cd-accumulated pupae, as evidenced by that the expression level of immune recognition gene (PGRP-SA), signal transduction genes (IMD, Dorsal, and Tube), as well as all antimicrobial peptide genes (e.g. Lysozym and Attacin) decreased significantly. Cd exposure decreased the content of glucose, trehalose, amino acid, and free fatty acid in H. cunea pupae. The expression of Hk2 in glycolysis pathway and the expression of Idh2, Idh3, Cs, and OGDH in TCA cycle pathway were significantly down-regulated in Cd-accumulated pupae. Taken together, exposure to Cd through the food chain causes oxidative damage on the offspring wasps and disrupts energy metabolism of the host insect, ultimately reducing the parasitic fitness of C. cunea to H. cunea pupae.

Highlights of Urban Entomology 2021: Chemical, Nonchemical, and Alternative Approaches to Urban Pest Management as We Adapt, Advance, Transform.

The 2021 annual meeting of the Entomological Society of America with the theme of "Adapt. Advance. Transform" guided the highlight compilation of urban entomology papers. Integrated pest management of urban pests relies on techniques and tools that adapt, advance, and transform over time to develop into new usable tactics and technologies; the review covers the following three themes: first, how science, researchers, and pest management professionals adapt to the changing environments; second, how urban pest management approaches and technologies advance using conventional and alternative strategies; and last, how transformation happens, leading to technological advances and sustainable pest management success. I selected papers on four groups of urban pests-ants, termites, bed bugs, and cockroaches-that were in the context of pest management in this highlights publication. Emphasis was placed on research regarding the efficacy of chemical (e.g., conventional pesticides, insect growth regulators), nonchemical, and alternative approaches (e.g., the use of heat, naturally derived compounds) for urban pests that help improve and implement sustainable pest management plans. These papers demonstrate the achievements of the urban entomology community while emphasizing the current challenges that we face from the far-reaching impact of climate change and insect pest adaptation and what should be prioritized.

Identification of the neuropeptide gene family and feeding regulation by neuropeptide Y in Mythimna separata (Lepidoptera: Noctuidae).

Mythimna separata is a crucial agricultural pest with polyphagous characteristic. Neuropeptide signaling, especially neuropeptide Y (NPY) involved in feeding regulation, is considered as a potential pest control target. In this study, we identified 50 neuropeptides including NPY of M. separata using transcriptome sequencing. Bioinformatics analysis showed that NPY had a conserved carboxyterminal motif of RGRYamide and shared very high homology across lepidopteran insects. Spatio-temporal expression profile articulated that NPY was mainly expressed in the larval stage, and with the highest expression in larval midgut and adult alimentary canal. RNAi knockdown by the injection of dsNPY into larvae significantly inhibited food uptake and body weight, delayed developmental duration, and also caused increase of trehalose and decrease of glycogen and total lipid compared to dsGFP. This study identified nearly the entire neuropeptide gene family of M. separata and further indicated that NPY signaling pathway might played a vital role in the feeding regulation and related to energy metabolism. Our results not only laid a preliminary foundation for functional studies on neuropeptide of M. separata, but also provided a potential molecular target for future pesticide development.

Silicon as resistance inducer to control black apphid Aphis craccivora Koch, 1854 in cowpea beans [Vigna unguiculata (L)] Walp

The black aphid Aphis craccivora (Koch, 1854) stands out between the bugs considered cowpea pests. The objective of this study was to evaluate the effects of silicon application on the resistance induction of cowpea plants to the black aphid A. craccivora. The experiment was conducted in the Entomology Laboratory of the Phytosanitary sector of the Centro de Ciências Agrárias at the Universidade Federal do Piauí. The effects of the application of silicon on biological aspects were evaluated using a completely randomized design, with four treatments and 40 repetitions, being: silicon in soil (T1), silicon in soil + leaf (T2), silicone leaf (T3), and control (T4). The following biological variables were evaluated: generation period, reproductive period, fecundity, and daily average of nymphs per female. The silicon and lignin contents were also evaluated in the plants. The silicic acid was applied in a 1% solution around the stem of the plants (soil), 15 days after emergence, by diluting 2 g of the product in 200 mL of water. However, the leaf application was carried out with sprayer five days after application in soil. The non-preference of A. craccivora on bean was also evaluated. The evaluations were performed after 24, 48 and 72 hours of infestation by counting nymphs at 24, 48 and 72 hours and adults at each leaf session. The application of silicon promotes the reduction of the production of nymphs, interfering in the biological aspects of A. craccivora, and has potential to be used in a cowpea pest management program in cowpea.

Influence of adjuvants added to teflubenzuron spray on resistant and susceptible strains of the soybean looper Chrysodeixis includens (Lepidoptera: Noctuidae) / Influência da adição de adjuvantes à calda de pulverização de teflubenzuron em linhagens resistentes e suscetíveis da lagarta falsa-medideira Chrysodeixis includens em soja (Lepidoptera: Noctuidae)

The soybean looper (SBL), Chrysodeixis includens (Walker, [1858]) (Lepidoptera: Noctuidae), is a soybean and cotton pest in South America countries. Field-evolved resistance of SBL to inhibitors of chitin biosynthesis has been reported in Brazil; however, this mode of action is still widely used against SBL. On this basis, we conducted laboratory bioassays to investigate if adjuvants (Nimbus®, TA 35®, Break-Thru® S 240, and Rizospray Extremo®) added to the teflubenzuron spray increase the mortality of SBL strains (resistant, heterozygous, and susceptible to chitin biosynthesis inhibitors). Using chromatography analysis, we also evaluated the amount of teflubenzuron on soybean leaves when applied alone or in combination with adjuvants. In laboratory bioassays, the biological activity of teflubenzuron increased against the susceptible SBL strain when adjuvants were added. In contrast, no relevant effects of adjuvants added to the teflubenzuron spray against heterozygous and resistant SBL larvae were detected. In leaf bioassays, even leaves from the upper third part of the plants containing a significantly higher amount of teflubenzuron (3.4 mg/kg vs 1.7 and 0.6 mg/kg); the mortality of SBL strains was similar when teflubenzuron was applied alone or in mixture with adjuvants. Our findings indicated that adjuvants added to teflubenzuron spray do not provide a substantial increase in the mortality of SBL strains resistant to chitin biosynthesis inhibitors. Therefore, it is necessary to reduce the use of this mode-ofaction insecticide against SBL and to give preference to other insecticides or control tactic.

A lagarta falsa-medideira, Chrysodeixis includens (Walker, [1858]) (Lepidoptera: Noctuidae), é uma praga da soja e do algodão nos países da América do Sul. A resistência de C. includens a inibidores da biossíntese de quitina tem sido relatada no Brasil. Entretanto, esse modo de ação ainda é amplamente utilizado para controle de C. includens. Com base nisso, conduzimos bioensaios em laboratório para investigar se adjuvantes (Nimbus®, TA 35®, Break-Thru® S 240 e Rizospray Extremo®) adicionados à calda inseticida de teflubenzuron aumentam a mortalidade de linhagens de C. includens (resistentes, heterozigotos e suscetíveis a inibidores da biossíntese de quitina). Usando análise cromatográfica, também avaliamos a quantidade de teflubenzuron em folhas de soja quando aplicado isolado ou em combinação com adjuvantes. Em bioensaios de laboratório, a atividade biológica do teflubenzuron aumentou para a linhagem suscetível quando os adjuvantes foram adicionados à calda inseticida. Em contraste, nenhum efeito relevante de adjuvantes adicionados ao teflubenzuron foi detectado para os heterozigotos e resistentes. Em bioensaios de folhas, mesmo naquelas do terço superior das plantas, as quais apresentaram uma maior deposição de teflubenzuron (3,4 mg/kg vs 1,7 e 0,6 mg/kg); a mortalidade das linhagens de C. includens foi semelhante quando o teflubenzuron foi aplicado isolado ou com adjuvantes. Nossos resultados indicam que os adjuvantes adicionados ao teflubenzuron não fornecem um aumento substancial na mortalidade de linhagens de C. includens resistentes aos inibidores da biossíntese de quitina. Portanto, é necessário reduzir o uso desse modo de ação para o manejo de C. includens e dar preferência a outros inseticidas ou tática de controle.

Distribution pattern of arthropods on the leaf surfaces of Acacia auriculiformis saplings / Padrão de distribuição de artrópodes nas superfícies foliares de plantas de Acacia auriculiformis

Acacia auriculiformis A. Cunn. Ex Benth. (Fabaceae), a non-native pioneer species in Brazil with fast growth and rusticity, is used in restoration programs. Our goal was to assess during a 24-month survey the pattern of arthropods (phytophagous insects, bees, spiders, and predator insects) on the leaf surfaces of A. auriculiformis saplings. Fourteen species of phytophagous, two of bees and eleven of predators were most abundant on the adaxial surface. The values of the ecological indexes (abundance, diversity, and species richness) and the rarefaction, and k-dominance curves of phytophagous, bees and arthropod predators were highest on the adaxial leaf surface of A. auriculiformis. The k-dominance and abundance of Aleyrodidae (Hemiptera) (both leaf surfaces), the native stingless bee Tetragonisca angustula Latreille (Hymenoptera: Apidae) (both leaf surfaces) and the ant Brachymyrmex sp. (adaxial surface) and Pheidole sp. (Hymenoptera: Formicidae) (abaxial surface) were the highest between the taxonomic groups of phytophagous, bees, and predators, respectively on A. auriculiformis saplings. The ecological indexes and rarefaction, abundance, and k-dominance curves of phytophagous insects, bees, and predators were highest on the adaxial leaf surface. The preference of phytophagous insects for the adaxial leaf surface is probably due to the lower effort required to move on this surface. Understanding the arthropod preferences between leaf surfaces may help to develop sampling and pest management plans for the most abundant phytophagous insects on A. auriculiformis saplings. Also, knowledge on the preference pattern of bees and predators may be used to favour their conservation.

Acacia auriculiformis A. Cunn. Ex Benth. (Fabaceae), espécie pioneira com rápido crescimento e rusticidade, é utilizada em programas de recuperação de áreas degradadas. O objetivo deste trabalho foi avaliar, durante 24 meses, o padrão de distribuição de artrópodes (insetos fitófagos, abelhas, aranhas e insetos predadores) nas superfícies foliares de A. auriculiformis. Quatorze espécies de fitófagos, duas de abelhas e onze de predadores foram mais abundantes na superfície adaxial. Índices ecológicos (abundância, diversidade e riqueza de espécies) e curvas de rarefação e dominância-k de fitófagos, abelhas e artrópodes predadores foram maiores na face adaxial de folhas de A. auriculiformis. A dominância-k e a abundância de Aleyrodidae (Hemiptera) (ambas as superfícies foliares), da abelha nativa sem ferrão Tetragonisca angustula Latreille (Hymenoptera: Apidae) (ambas as superfícies foliares) e das formigas Brachymyrmex sp. (superfície adaxial) e Pheidole sp. (Hymenoptera: Formicidae) (superfície abaxial) foram as maiores entre os grupos taxonômicos de fitófagos polinizadores e predadores, respectivamente, em plantas jovens de A. auriculiformis. A abundância, diversidade e riqueza e as curvas de rarefação e dominância-k de artrópodes fitófagos, abelhas e predadores foram maiores nas superfícies adaxiais das folhas dessa árvore. A preferência pela superfície adaxial da folha se deve, provavelmente, ao menor esforço para se movimentarem na mesma. Compreender as preferências dos artrópodes pelas superfícies foliares pode auxiliar no desenvolvimento de planos de amostragem e manejo de pragas em A. auriculiformis. Além disso, o conhecimento da distribuição de abelhas e predadores pode favorecer a conservação desses insetos.

Impact of nitrogen and phosphorus fertilizers on Cry1Ac protein contents in transgenic cotton / Impacto de fertilizantes de nitrogênio e fósforo nos conteúdos de proteína Cry1Ac em algodão transgênico

Application of different fertilizers to check the efficiency of expression of Bt (Bacillus thuringiensis) gene in one of the leading commercialized crops (cotton) against Lepidopteran species is of great concern. The expression of Cry protein level can be controlled by the improvement of nutrients levels. Therefore, the myth of response of Cry toxin to different combinations of NP fertilizers was explored in three Bt cotton cultivars. Combinations include three levels of nitrogen and three levels of phosphorus fertilizers. Immunostrips and Cry gene(s) specific primer based PCR (Polymerase Chain Reaction) analysis were used for the presence of Bt gene that unveiled the presence of Cry1Ac gene only. Further, the ELISA (enzyme-linked immunosorbent assay) kit was used to quantify the expression of Cry1Ac protein. Under various NP fertilizers rates, the level of toxin protein exhibited highly significant differences. The highest toxin level mean was found to be 2.3740 and 2.1732 µg/g under the treatment of N150P75 kg ha-¹ combination while the lowest toxin level mean was found to be 0.9158 and 0.7641 µg/g at the N50P25 kg ha-¹ level at 80 and 120 DAS (Days After Sowing), respectively. It was concluded from the research that the usage of NP fertilizers has a positive relation with the expression of Cry1Ac toxin in Bt cotton. We recommend using the N150P50 kg ha-1 level as the most economical and practicable fertilizer instead of the standard dose N100P50 kg ha-¹ to get the desired level of Cry1Ac level for long lasting plant resistance (<1.5). The revised dose of fertilizer may help farmers to avoid the cross-resistance development in contradiction of insect pests.

A aplicação de diferentes fertilizantes para verificar a eficiência da expressão do gene Bt (Bacillus thuringiensis) em uma das principais culturas comercializadas (algodão) contra espécies de lepidópteros é uma grande preocupação. A expressão do nível de proteína Cry pode ser controlada pela melhoria dos níveis de nutrientes. Portanto, o mito da resposta da toxina Cry a diferentes combinações de fertilizantes NP foi explorado em três cultivares de algodão Bt. As combinações incluem três níveis de nitrogênio e três níveis de fertilizantes de fósforo. A análise de PCR (reação em cadeia da polimerase) específica para o gene (s) Immunostrips e Cry (s) foi usada para a presença do gene Bt que revelou a presença do gene Cry1Ac apenas. Além disso, o kit ELISA (ensaio de imunoabsorção enzimática) foi usado para quantificar a expressão da proteína Cry1Ac. Sob várias taxas de fertilizantes NP, o nível de proteína de toxina exibiu diferenças altamente significativas. A média do nível mais alto de toxina foi de 2,3740 e 2,1732 µg / g sob o tratamento da combinação N150P75 kg ha-¹, enquanto a média do nível mais baixo de toxina foi de 0,9158 e 0,7641 µg / g no nível de N50P25 kg ha-¹ em 80 e 120 DAS (dias após a semeadura), respectivamente. Concluiu-se com a pesquisa que o uso de fertilizantes NP tem relação positiva com a expressão da toxina Cry1Ac no algodão Bt. Recomendamos o uso do nível de N150P50 kg ha-¹ como o fertilizante mais econômico e praticável em vez da dose padrão N100P50 kg ha-¹ para obter o nível desejado de nível de Cry1Ac para resistência de planta de longa duração (<1,5). A dose revisada de fertilizante pode ajudar os agricultores a evitar o desenvolvimento de resistência cruzada em contradição com as pragas de insetos.

Evaluation of economic loss caused by Indian crested porcupine (Hystrix indica) in agricultural land of district Muzaffarabad, Azad Jammu and Kashmir, Pakistan / Avaliação da perda econômica causada pelo porco-espinho de crista indiano (Hystrix indica) em terras agrícolas dos distritos de Muzaffarabad, Azad Jammu e Caxemira, Paquistão

The Indian crested porcupine (Hystrix indica) is a vertebrate pest of agricultural lands and forest. The study was aimed to report the damage to local crops by the Indian crested porcupine (Hystrix indica) in the Muzaffarabad District. A survey was conducted to identify the porcupine-affected areas and assess the crop damage to the local farmers in district Muzaffarabad Azad Jammu and Kashmir (AJK) from May 2017 to October 2017. Around 19 villages were surveyed, and a sum of 191 semi-structured questionnaires was distributed among farmers. Crop damage was found highest in village Dhanni where a porcupine destroyed 175 Kg/Kanal of the crops. Regarding the total magnitude of crop loss, village Danna and Koomi kot were the most affected areas. More than half (51.8%) of the respondents in the study area suffered the economic loss within the range of 101-200$, and (29.8%) of the people suffered losses in the range of 201-300$ annually. Among all crops, maize (Zea mays) was found to be the most damaged crop ranging between 1-300 Kg annually. In the study area, porcupine also inflicted a lot of damages to some important vegetables, including spinach (Spinacia oleracea), potato (Solanum tuberosum) and onion (Allium cepa). It was estimated that, on average, 511Kg of vegetables are destroyed by porcupine every year in the agricultural land of Muzaffarabad. It was concluded that the Indian crested porcupine has a devastating effect on agriculture which is an important source of income and food for the local community. Developing an effective pest control strategy with the help of the local government and the Wildlife department could help the farmers to overcome this problem.

O porco-espinho de crista indiano (Hystrix indica) é uma praga vertebrada de terras agrícolas e florestais. No estudo atual, o dano às plantações locais pelo porco-espinho de crista indiano (Hystrix indica) foi relatado pela primeira vez no distrito de Muzaffarabad. O estudo foi projetado para investigar a perda econômica causada pelo porco espinho de crista indiano (Hystrix indica) nos distritos de Muzaffarabad, Azad Jammu e Caxemira (AJK) de maio de 2017 a outubro de 2017. Um estudo baseado em pesquisa foi conduzido para identificar as áreas afetadas por porcos-espinhos e avaliar os danos às colheitas para os agricultores locais. Cerca de 19 aldeias foram pesquisadas e um total de 191 questionários semiestruturados foi distribuído entre os agricultores. Os danos às colheitas foram encontrados mais intensamente na aldeia Dhanni, onde um porco-espinho destruiu 175 kg / Kanal das colheitas. Em relação à magnitude total da perda de safra, as aldeias Danna e Koomi Kot foram as áreas mais afetadas. Mais da metade (51,8%) dos entrevistados na área de estudo sofreu perdas econômicas na faixa de 101-200 $, e 29,8% das pessoas sofreram perdas na faixa de 201-300 $ anualmente. Entre todas as culturas, o milho (Zea mays) foi considerado a cultura mais danificada, variando entre 1-300 kg anualmente. Na área de estudo, o porco-espinho também causou muitos danos a alguns vegetais importantes, incluindo espinafre (Spinacia oleracea), batata (Solanum tuberosum) e cebola (Allium cepa). Estimou-se que, em média, 511 kg de vegetais são destruídos pelo porco-espinho todos os anos nas terras agrícolas de Muzaffarabad. Concluiu-se que o porco-espinho de crista indiano tem um efeito devastador na agricultura, que é importante fonte de renda e alimento para a comunidade local. O desenvolvimento de uma estratégia eficaz de controle de pragas com a ajuda do governo local e do Departamento de Vida Selvagem pode ajudar os agricultores a superar esse problema.

Characterization of wheat-Thinopyrum bessarabicum genetic stock for stripe rust and Karnal bunt resistance / Caracterização do estoque genético de trigo-Thinopyrum bessarabicum para resistência de ferrugem e Karnal bunt

Utilization of modern breeding techniques for developing high yielding and uniform plant types ultimately narrowing the genetic makeup of most crops. Narrowed genetic makeup of these crops has made them vulnerable towards disease and insect epidemics. For sustainable crop production, genetic variability of these crops must be broadened against various biotic and abiotic stresses. One of the ways to widen genetic configuration of these crops is to identify novel additional sources of durable resistance. In this regard crops wild relatives are providing valuable sources of allelic diversity towards various biotic, abiotic stress tolerance and quality components. For incorporating novel variability from wild relative’s wide hybridization technique has become a promising breeding method. For this purpose, wheat-Th. bessarabicum amphiploid, addition and translocation lines have been screened in field and screen house conditions to get novel sources of yellow rust and Karnal bunt resistant. Stripe rust screening under field conditions has revealed addition lines 4JJ and 6JJ as resistant to moderately resistant while addition lines 3JJ, 5JJ, 7JJ and translocation lines Tr-3, Tr-6 as moderately resistant wheat-Thinopyrum-bessarabicum genetic stock. Karnal bunt screening depicted addition lines 5JJ and 4JJ as highly resistant genetic stock. These genetic stocks may be used to introgression novel stripe rust and Karnal bunt resistance from the tertiary gene pool into susceptible wheat backgrounds.

A utilização de técnicas modernas de melhoramento para o desenvolvimento de tipos de plantas uniformes e de alto rendimento, em última análise, estreitando a composição genética da maioria das culturas. A composição genética restrita dessas plantações tornou-as vulneráveis a doenças e epidemias de insetos. Para uma produção agrícola sustentável, a variabilidade genética dessas culturas deve ser ampliada contra vários estresses bióticos e abióticos. Uma das maneiras de ampliar a configuração genética dessas culturas é identificar novas fontes adicionais de resistência durável. A esse respeito, os parentes selvagens das culturas estão fornecendo fontes valiosas de diversidade alélica para vários componentes de qualidade e tolerância ao estresse abiótico e biótico. Para incorporar a nova variabilidade da ampla técnica de hibridização de parente selvagem tornou-se um método de reprodução promissor. Para esse efeito, trigo-Th. As linhas anfiploides, de adição e translocação de bessarabicum foram selecionadas em condições de campo e de casa de tela para obter novas fontes de ferrugem amarela e resistência ao bunt de Karnal. A triagem de ferrugem em faixas em condições de campo revelou as linhas de adição 4JJ e 6JJ como resistentes a moderadamente resistentes, enquanto as linhas de adição 3JJ, 5JJ, 7JJ e as linhas de translocação Tr-3, Tr-6 como estoque genético de trigo-Thinopyrum bessarabicum moderadamente resistente. A triagem Karnal bunt descreveu as linhas de adição 5JJ e 4JJ como estoque genético altamente resistente. Esses estoques genéticos podem ser usados para introgressão da nova ferrugem e resistência ao bunt de Karnal do pool genético terciário em origens de trigo suscetíveis.