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The Varroa destructor (hereafter referred to as Varroa) is a major pest of honeybees that is generally controlled using pyrethroid-based acaricides. However, resistance to these insecticides has become a growing problem, driven by the acquisition of knockdown resistance (kdr) mutations in the mite’s voltage-gated sodium channel (vgsc) gene. Resistance mutations in the vgsc gene, such as the L925V mutation, can confer resistance to pyrethroids like flumethrin and tau-fluvalinate. Monitoring genotypic resistance through molecular mutation screening is crucial for tracking and mitigating resistance spread. In this study, the frequency of resistance mutations in the vgsc was examined using a Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) approach in Varroa populations sampled throughout the Mediterranean, Aegean, and Black Sea regions of Türkiye. Considering all the samples analyzed, the results demonstrated a mean resistance allele frequency of 83.29%, indicating a relatively high frequency of resistant alleles. We observed 94.58%, 85.71%, and 69.58% resistant allele frequencies in populations sampled from the Mediterranean, Aegean, and Black Sea regions, respectively, in our study. The results of our investigation demonstrated substantial regional variations in the frequencies of resistant alleles among Varroa populations throughout Türkiye, with notably elevated resistance levels observed in the Mediterranean and Aegean regions. Due to the significant resistance mutation frequency differences between both provinces and regions, long-term monitoring of resistance alleles and the planning of regional control strategies are required for effective control of this pest. [ABSTRACT FROM AUTHOR]

Tuta absoluta is a major tomato pest. An insecticide that acts in several phases of the pest's life cycle can present greater control efficiency and amplitude of action, possessing greater capacity in reducing the insect population. In this context, the objective of this study was to determine the lethal concentrations for caterpillars and adults of T. absoluta and to evaluate whether the insecticide chlorantraniliprole influences the behavior and oviposition of adults of T. absoluta as well as the mortality of caterpillars. We determined lethal concentrations (LCs) and side effects in laboratory oviposition tests, and on oviposition and mortality of adults in field trials were evaluated. Plants treated with LC50 of chlorantraniliprole showed a low number of eggs per plant. The toxicity was higher in larvae exposed to all concentrations of chlorantraniliprole. In the field, the number of T. absoluta adults and eggs in plants treated with chlorantraniliprole was lower than the control. Our results indicate that chlorantraniliprole has toxicity against T. absoluta adults, eggs, and larvae. Other effects on the oviposition behavior performance of this specie can help implement integrated pest management programs. [ABSTRACT FROM AUTHOR]

Following commercial use of plant essential oils in pest control, their slow-release formulations have been developed in order to increase their effectiveness and solve their instability problem. In the present study, at first, lethal effects of peppermint (Mentha piperita L.) and rosemary (Rosmarinus officinalis L.) essential oils as emulsions and nano-capsules on the tomato leaf-miner was determined by the leaf-dipping method. Mortality of different concentrations (1, 5, 10, 20, and 40 percent) recorded at 24, 48, and 72 h after treatment. Then, negative effects of these essential oils on life table parameters were evaluated at 10% concentration. The results of the toxic effects of these essential oils at the selected concentration showed a significant increase in the larval duration in both treatments compared to that of control. The longest larval duration was observed in nano-capsule formulation of rosemary (9.24 ± 0.15 day) and the lowest larval duration was observed in the control (7.78 ± 0.16 day). However, the nano-capsule formulations of essential oils had no effect on the adult longevity, but peppermint nano-capsule significantly decreased the ovipositional period compared to that of control and rosemary nano-capsule. Fertility and survival rates were also significantly decreased in females treated with rosemary nano-capsule. In general, rosemary essential oil has the ability to use in integrated pest management programs because of a reasonable reduction in the pest developmental parameters, higher inhibition effect on adult female oviposition, and lower damages to plants. [ABSTRACT FROM AUTHOR]

Alligatorweed [Alternanthera philoxeroides (Mart.) Griseb.; Amaranthaceae] is a globally problematic, aquatic invasive weed with a long history as a target for control efforts. Although chemical and biological control methods have been widely studied to manage alligatorweed infestations, many research questions remain unanswered. This paper seeks to assess the efficacy of two understudied alligatorweed control methods: submersed herbicide applications and biological control with alligatorweed thrips (Amynothrips andersoni O'Neill 1968; Thysanoptera: Phlaeothripidae). These assessments were carried out in mesocosm experiments, in two stages. The first stage tested five herbicides applied as submersed injections at two different rates, and the second tested the same five herbicides alone and in combination with alligatorweed thrips biological control. The submersed herbicides used in this study were penoxsulam, bispyribac-sodium, imazamox, fluridone, and topramezone. The control effect of these treatments was measured as percent biomass reduction 12 weeks after treatment. These data showed that, with the exception of bispyribac-sodium, submersed herbicide application was generally successful at reducing alligatorweed biomass. Also, thrips biological control was broadly effective at reducing alligatorweed biomass. However, these data did not identify a specific herbicide whose control was significantly benefitted by thrips biological control at the rates these herbicides were applied. While the results of this study show promise for combining submersed herbicides and alligatorweed thrips for integrated alligatorweed management, questions remain regarding this combined control strategy including whether or not these results translate to the field. [ABSTRACT FROM AUTHOR]

Garlic is one of the most popular spices in the world and the second most widely cultivated Allium species next to the onion. Garlic production is reduced due to many biotic and abiotic factors, among which white rot disease caused by Stromatinia cepivora (Berk.) Whetzel causes severe yield losses. The study was conducted to evaluate the combined effects of chemical fungicides and garlic varieties on the epidemic development of white rot disease. The experiment was conducted at Chefanen Kebele using three garlic varieties and three chemicals during the 2019 and 2020 seasons. The experimental design was a randomized complete block with three replicates. The application of Apron Star 42, a commercial fungicide containing Thiametoxam 20%, Metalaxyl-M 20% and Difenconazole 2%, significantly reduced the white rot disease on all varieties as compared to the untreated local variety. Bishoftu Nech and MM-98 varieties exhibited fast emergence as compared to the local variety, consequently increasing the yield and yield components of garlic. The application of Apron Star 42, significantly increased yield parameters compared to the untreated control. The significant effect and the negative correlations of days to maturity, growth parameters, yield, and yield components with disease parameters indicated that the white rot disease had a very crucial impact on garlic yield. Application of Apron Star 42 to improved garlic varieties is recommended to reduce the severity of white rot infections and to increase garlic production in the study area. [ABSTRACT FROM AUTHOR]

Most strawberry growers in Brazil use imported transplants due to their higher quality in terms of plant health and productivity. However, there is a risk of entry of quiescently infecting pathogens such as Botrytis species and/or isolates resistant to different fungicides. In this work, we investigated the incidence of Botrytis in imported transplants, and identified the species. In addition, isolates were characterized for their pathogenicity in fruit and sensitivity to seven fungicides (procymidone, fludioxonil, iprodione, cyprodinil, pyrimethanil, boscalid and fluazinam). The average incidence of Botrytis spp. in transplants imported from Chile, Argentina, and Spain was 43.5%. A total of 79 isolates were identified molecularly as B. cinerea and the pathogenicity in fruit was confirmed for a subsample of 14 isolates. To evaluate sensitivity to fungicides, the following discriminatory doses were used: procymidone (P) (10 µg/mL), fludioxonil (F) (0.5 µg/mL), iprodione (I) (10 µg/mL), cyprodinil (C) (10 µg/mL), pyrimethanil (PY) (10 µg/mL), boscalid (B) (50 µg/mL) and fluazinam (FL) (1 µg/mL). As a result, 24 resistant phenotypes were identified with the most frequent being the phenotype with resistance to three fungicides (C-PY-B). The isolates with low sensitivity to cyprodinil and pyrimethanil fungicides, which are not yet widely used in Brazil, represent a risk for strawberry production and should be considered in disease management and future fungicide monitoring programs. [ABSTRACT FROM AUTHOR]

This work evaluated if strategic control based on no more than three or four annual treatments is useful to control Rhipicephalus microplus infestations on cattle when it is applied to intensive rotational grazing and silvopastoral systems with high stocking rates in subtropical areas. In the intensive rotational grazing system, three annual treatments with chemical acaricides were applied on cattle in two different schemes: between spring and early summer and from late winter and late spring. Strategic control based on three treatments with chemical acaricides from late winter to late spring plus an additional fourth treatment in summer was tested in the silvopastoral system. In the intensive rotational grazing systems, the control schemes allow to reach a significant reduction in the tick load on cattle considering a time interval from spring to autumn. However, the efficacy levels were not high enough in some specific moments, namely, the tick counts of summer and autumn (there were not significant differences between treated and control groups). The scheme evaluated in the silvopastoral grazing system yielded better results than those tested for the intensive rotational system, because significant differences in tick load between treated and control groups were observed in all post-treatment counts and when the analysis was performed for the whole study period. However, values of efficacy in the count-by-count comparison were disparate, ranging from 64.1 to 99.7. Although the efficacy values obtained in the silvopastoral system were better than those of the rotational grazing systems, the total tick load on treated cattle in autumn was not low enough (mean abundance values 25.14 and 38.14). Ticks were more evenly distributed among hosts in late summer and autumn than in spring or early summer, where few hosts carry most of the ticks. Some management strategies as intensive rotational systems or silvopastoral structures can lead to a more efficient forage use, but they imply greater tick challenge than in extensive grazing systems. In these situations, the schemes of strategic control bases on three or four annual treatments should be complemented with additional tactical treatments in late summer or autumn. [ABSTRACT FROM AUTHOR]

Background: Control of blackleg disease of canola caused by the fungus Leptosphaeria maculans relies on strategies such as the inhibition of growth with fungicides. However, other chemicals are used during canola cultivation, including fertilizers and herbicides. There is widespread use of herbicides that target the acetolactate synthase (ALS) enzyme involved in branched chain amino acid synthesis and low levels of these amino acids within leaves of Brassica species. In L. maculans the ilv2 gene encodes ALS and thus ALS-inhibiting herbicides may inadvertently impact the fungus. Methods and results: Here, the impact of a commercial herbicide targeting ALS and mutation of the homologous ilv2 gene in L. maculans was explored. Exposure to herbicide had limited impact on growth in vitro but reduced lesion sizes in plant disease experiments. Furthermore, the mutation of the ilv2 gene via CRISPR-Cas9 gene editing rendered the fungus non-pathogenic. Conclusion: Herbicide applications can influence disease outcome, but likely to a minor extent. [ABSTRACT FROM AUTHOR]

Absorption and translocation of chemical insecticides in plants are complex processes and influenced by different factors. This study investigated the translocation of chlorantraniliprole and cyantraniliprole in soybean plants in greenhouse, using Helicoverpa armigera as a bioindicator and chemical quantification in LC–MS/MS. Two experiments were conducted in the greenhouse and laboratory. Significant acropetal and basipetal movement in leaves was confirmed for both anthranilic diamides. Application via seed treatment (ST) and foliar spray of chlorantraniliprole and cyantraniliprole resulted in significant uptake and translocation via xylem to the flowers emitted after the application of treatments. The mortality of H. armigera with foliar application of chlorantraniliprole (10 g a.i./ha−1) and cyantraniliprole (50 g a.i./ha−1) was 60% and 45% higher than the control treatment, respectively. The use of both insecticides via ST resulted in a residual effect of approximately 60 days after application. The anthranilic diamides studied have shown to have physicochemical characteristics that allow their translocation to structures not yet present at the time of application. Thus, chlorantraniliprole and cyantraniliprole may be an alternative for the management of lepidopteran pests that cause damage during soybean flowering. [ABSTRACT FROM AUTHOR]

The use of insecticides on a large scale and applied at the wrong time can increase the cost of potato production. Good agricultural pest management practices can reduce the number of insecticide applications and promote the sustainability of potato production in modern agriculture. Thus, the objective was to compare the costs and revenues of a pest management system that uses monitoring (IPM-integrated pest management) with a conventional system (calendar-based insecticide application) in the potato crop. Two experiments were carried out: experiment 1, carried out in the summer with the cultivars Ágata, Atlantic, and FLs 2027, 1867, 2215, and 2221, and experiment 2, carried out in autumn with the cultivar Ágata. The densities of sucking insects, defoliators, and natural enemies were evaluated and compared. In both experiments, treatments were based on pest monitoring (insecticide applications when reaching economic thresholds [ETs]) and a conventional system (calendar-based insecticide application). In experiment 2, a control group was also carried out without the use of insecticides. In experiment 1, with the use of pest monitoring, the number of sprays was reduced by 66.67%, pest control costs were decreased by 60.86%, and there was an increase of 8.97% in net income from potato production. Whilst in experiment 2, the number of sprays was reduced by 71.42%, pest control costs were decreased by 51.38%, and an increase of 12.75% in net revenue from potato production was observed. Thus, it is concluded that the application of insecticides when the pest population reaches the economic threshold (ET) reduces insecticide applications and costs and increases net income in the potato crop. [ABSTRACT FROM AUTHOR]

During the last 15 years in Serbia, there has been an invasion of H. annuus across the country. Plants were initially limited to non-cultivated areas near arable fields, while in recent years the species has started to occur and establish populations in crop fields, especially into wide-row crops. We tested eight herbicides in two greenhouse experiments: 1) a dose-response study; 2) an efficacy study with reduced herbicide rates adding an adjuvant. The tested herbicides showed satisfactory weed control, where all estimated effective doses 90 (ED90) were lower than the recommended field rate for each herbicide, except for dicamba. The addition of non-ionic surfactants significantly increased the efficacy of glyphosate, mesotrione, rimsulfuron, and foramsulfuron. Whereas, there was no clear advantage to adding an adjuvant to bentazone and tembotrione, as the H. annuus population was already very sensitive (plants died in 1/8 of recommended rate in a dose-response study). All tested herbicides, except dicamba, can be used for satisfactory H. annuus control in maize, while glyphosate can be used for control of the species in non-agricultural lands. [ABSTRACT FROM AUTHOR]

The article discusses the importance of fungicides in modern agriculture and the potential consequences of further restrictions on their use. It highlights the role of fungicides in securing global food production and reducing hunger rates. The article also criticizes the proposed sustainable use regulation (SUR) by the EU, arguing that it overestimates the risks of plant protection products and ignores the significant reductions in risks that have already been achieved. It warns that further restrictions on crop protection could have negative effects on agricultural production, profitability, and the environment. The article concludes that effective crop protection will remain essential for food security in the foreseeable future. [Extracted from the article]

Background: Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), the fall armyworm (FAW), has recently invaded Egypt and poses serious threats to maize farmers as it causes huge economic costs and yield losses. Selection of efficient insecticides and appropriate methods of application can be a problem to control this pest. Methods: Two-year field studies to effectiveness of whorl application (sand mixed or spray) of seven insecticides comprising new insecticides generations with conventional insecticides from different groups at maximum recommended dosage field rate against FAW on yield of maize was evaluated in maize fields at El-Qualubia Governorate, Egypt. Results: In plots treated with insecticide mixed in sand, all tested insecticides recorded a significant decrease in FAW larvae with significantly higher yields than those treated with spraying or untreated plots. However, among tested insecticides in both applications, chlorantraniliprole was found to be the most effective followed by emamectin benzoate and spinosad and these insecticides gave better control FAW with higher yield than conventional insecticides tested. In this context, the highest decrease in FAW density was recorded in plots treated with chlorantraniliprole mixed in sand or sprayed (93.69% for 2021; 91.59% for 2022) and (84.74% for 2021; 85.78% for 2022), respectively, as well as a significantly high yield. However, lambda-cyhalothrin recorded the highest density of FAW (33.86% for 2021; 32.72% for 2022) in the treated plots with spraying with lowest significant yield during the 2021 and 2022 seasons in the treated plots with spraying by 8.98 and 8.00%, respectively, increase over control plots. Conclusions: These results indicate that insecticides mixed in sand application are more efficacious against FAW larvae along with yield increase than spraying. [ABSTRACT FROM AUTHOR]

Multiple arthropod pests can affect the same crop in agricultural systems, requiring the integration of control methods. In the present study, the effects of residual exposure to four broad-spectrum insecticides/acaricides (azadiractin, abamectin, chlorfenapyr, and fenpyroximate) on immature (development and survival time) and adult females (longevity, fecundity, and fertility life table parameters) of the predatory mite Neoseiulus barkeri were evaluated. Additionally, the insecticides/acaricides were categorized according to their selectivity based on the classification proposed by the International Organization for Biological Control (IOBC) for assessing the susceptibility of arthropods in laboratory experiments. Method 004, proposed by the Insecticide Resistance Action Committee (IRAC), was adopted for the bioassays with predators exposed to insecticide-acaricide residues. Among the insecticides/acaricides studied, azadirachtin had minimal effects on immature and adult N. barkeri (all non-significant) and was considered harmless based on the classification of toxicity according to the standards/categories proposed by the IOBC. All other insecticides/acaricides affected immature and adult N. barkeri and were considered slightly harmful in terms of toxicity, according to the IOBC. [ABSTRACT FROM AUTHOR]

Conservation biological control techniques support integrated pest management (IPM) and insecticide resistance management (IRM) by restraining pest resurgence and outbreaks of secondary pests. The lady beetle Eriopis connexa (Germar) (Coleoptera: Coccinellidae) is among the natural enemies in agricultural systems of brassica crops and their populations may be disrupted by exposure to insecticides. Pyrethroid-resistant and pyrethroid-susceptible E. connexa larvae and adults were exposed to eight insecticides (cyantraniliprole, chlorantraniliprole, chlorfenapyr, deltamethrin, spinosad, spiromesifen, methomyl, and pymetrozine) that target different pests of brassica crops. Evaluations were conducted on larval and adult survival, larval developmental time, fecundity and egg viability across 30 days, and consumption of Lipaphis pseudobrassicae (Davis) (Hemiptera: Aphididae) or larvae of Plutella xylostella (L.) (Lepidoptera: Plutellidae) during the exposure to the insecticides. In addition, the levels of aphids and diamondback moths infestation in field cages were evaluated as a function of insecticide application and release of the lady beetles. Neither survival of larvae and adult beetles, nor fecundity, were affected by the insecticides. Surviving lady beetles from pyrethroid-resistant and pyrethroid-susceptible populations consumed aphids and diamondback moth larvae when exposed simultaneous to the insecticides targeting these pest species. There was no additive effect of the control of these pests when lady beetles were used alone or with insecticides. The findings showed the compatibility of this natural enemy with selected insecticides through multiple exposures targeting different pest species combining different insecticide modes of action. [ABSTRACT FROM AUTHOR]

Sweet cherry is a high-value fresh market crop whose commercial value is directly related to fruit quality. Morphological studies and phylogenetic analyses have shown that a distinct powdery mildew species, Podosphaera cerasi, infects sweet cherry in orchards, nurseries, and greenhouses for stock production. The fungal species P. clandestina, which was thought to cause powdery mildew infection in sweet cherry, is now confined to the powdery mildew that infects Crataegus spp. The intricate nomenclatural-taxonomic history of sweet cherry powdery mildew is briefly outlined. This review has been written to serve production managers as well as applied and basic research regarding control of this pathogen. The economic impact of this powdery mildew, environmental aspects contributing to its epidemiology, management options including both conventional chemical and biopesticide products, as well as mycoviruses associated with P. cerasi are discussed. Additionally, an overview of host–pathogen resistance based on cultivar, fungicide resistance, the role of chasmothecia in epidemic initiation, and susceptible stages of fruit to infection are discussed. [ABSTRACT FROM AUTHOR]

The mango gall midge Procontarinia mangicola (Shi) that infests fresh leaves of mango is an important pest of this plant in southern Japan. We examined the effects of 16 insecticides on the mortality of P. mangicola to find an effective insecticide for the control of this pest insect. After dipping leaves infested by larvae in dilutions of 16 insecticides in the laboratory, corrected mortality defined as highly effective was observed when the leaves were treated with DMTP of organophosphate and ethiprole of phenylpyrazole, two neonicotinoids including nitenpyram and dinotefuran, two spinosyns including spinosad and spinetoram during the larval stage. Although the mortality was 0% at larval stage after treatment with pyrifluquinazon, 88.2% of gall midges died during from leaving the leaves as mature larvae to adult emergence. In greenhouses, the number of galls was significantly reduced on mango trees sprayed with DMTP or dinotefuran compared with non-sprayed control trees. The insecticidal effect was detected when spraying of dinotefuran was made even before the appearance of new leaves that were later infested by gall midges. These results would be useful in selecting effective insecticides for the control of mango gall midges and for the registration as agricultural chemicals. [ABSTRACT FROM AUTHOR]

The red imported fire ant Solenopsis invicta Buren (Hymenoptera: Formicidae) causes serious damage worldwide as an invasive alien species. The species has expanded its range to the Pacific Rim since 2000s and Japan has faced its multiple introductions since 2017. While colony-level control methods are urgently needed, testing living colonies of the unestablished species is challenging especially due to various restrictions under the COVID-19 pandemic. Here, we proposed alternative long-term toxicity assays using artificial colonies of Tetramorium tsushimae Emery (Hymenoptera: Formicidae), a Japanese native species belonging to the same subfamily (Myrmicinae) as S. invicta. We conducted an acute toxicity test to determine if T. tsushimae is a suitable substitute for S. invicta using fipronil and found the LD50 value in T. tsushimae was close to that in S. invicta. Then, we conducted the long-term toxicity test with fipronil and two insect growth regulators (pyriproxyfen and etoxazole) using artificial colonies of T. tsushimae. All workers and larvae in the fipronil-treated colonies died within 3 days of treatment initiation. Emergence of new workers was observed after 18 days in the etoxazole-treated and control colonies, but not in the pyriproxyfen-treated colonies. We concluded that fipronil was the most promising insecticide for post-establishment control, and pyriproxyfen was effective as a toxic-bait agent for colony-level control. [ABSTRACT FROM AUTHOR]

The importance of bacterial leaf streak (BLS) of corn caused by Xanthomonas vasicola pv. vasculorum (Xvv) has been increasing worldwide and there are no studies on its chemical control. The aim of this study was to determine the in vitro sensitivity of Xvv isolates to different chemicals and to evaluate the control of BLS under greenhouse conditions. Tests were carried out with chemicals based on copper oxychloride, copper oxychloride + mancozeb and copper oxychloride + fluxapyroxad and also in combinations with imulsionable mineral oil. For the in vitro test, the chemicals were added to nutrient agar culture medium at the dosages of 1, 5, 10, 20, 50, 100, 200 and 400 μg mL−1 of metallic copper. Aliquots of 5 μL of 108 CFU mL−1 bacterial suspension were placed on the culture medium and incubated at 28 °C. In vitro treatments with copper oxychloride + fluxapyroxad showed bacterial growth inhibition starting from 20 μg mL−1; and for copper oxychloride + mancozeb and copper oxychloride from 50 μg mL−1. The control of BLS under greenhouse conditions was evaluated on corn plants at the V3 phenological vegetative stage sprayed with the chemicals. The corn plants were inoculated with a 108 CFU mL−1 suspension of a Xvv strain. Copper oxychloride + mancozeb and copper oxychloride were the most effective products to control corn BLS. However, symptoms of phytotoxicity were observed in the plants that received applications of these products in the tested dosages of 2 to 5 mL L−1. [ABSTRACT FROM AUTHOR]

The fungicidal and nematicidal properties of fluopyram were assessed against Rhizoctonia solani (sheath blight) and Meloidogyne graminicola (rice root-knot) pathogens of rice in single and concomitantly inoculated pots during two consecutive cropping seasons (2017 and 2018) on a susceptible rice cultivar Pusa Sugandha-5. Standard fungicides, azoxystrobin and nematicide, carbofuran were used to compare the efficiency of fluopyram. The plants grown in the soil singly inoculated with 2 g R. solani (2 × 106 CFU/g) and 1000 J2s of M. graminicola suffered a suppression of 13–30% in the plant growth and 20–29% in grain yield. However, simultaneous inoculation of both the pathogens did not reveal any significant change in the disease severity but marginally affect the plant growth and yield when compared to their individual effects. Soil treatment with fluopyram reduced the adverse effect of the nematode and fungus in simultaneously inoculated plants but significantly varied with fungus and nematode alone inoculation. Soil application (SA) with fluopyram proved most efficacious against root-knot nematode and reduced the disease severity by 67–74% and reproduction factor by 66–70%, resulted in a 17–32% plant growth promotion and yield enhancement. Fluopyram also significantly reduced the sheath blight fungus and suppressed the disease severity by 47–53% and soil population by 68%, resulted in a 9–31% plant growth promotion and yield enhancement. The study demonstrated that there was no interaction between R. solani and M. graminicola. Application of fluopyram effectively controls sheath blight and rice root-knot disease in rice and offers to be an alternative chemical for effective management of R. solani and M. graminicola in the areas/fields where sympatric infestations occur. [ABSTRACT FROM AUTHOR]

Citrus canker and citrus black spot are two of the most important diseases in the São Paulo (SP) citrus belt, Brazil. Canker control was based on an eradication program for six decades, but after a change in the legislation in 2017, the disease has been managed along with black spot. Although copper is a common pesticide for control of canker and black spot, spray setups have been established separately for each disease. The aim of this study was to determine copper rates and spray intervals for joint management of the two diseases. Two field trials (one for each disease) were conducted during two seasons. Control of canker or black spot was assessed with sprays at 14 or 21-day intervals using 10 to 63 mg metallic copper/m3 tree canopy. Copper was also assessed for efficacy against black spot at 28-day spray intervals using 32 and 53 mg/m3. Copper treatments with 42 mg/m3 every 21 days and 32 mg/m3 every 14 days showed the best cost-benefit for canker control. These treatments reduced leaf canker incidence and fruit drop by up to 60%. Black spot symptoms and fruit drop were consistently reduced (by up to 90% and 60%, respectively) in both seasons by rates from 32 to 63 mg/m3 and intervals of up to 28 days. Thus, the combination of 32 mg metallic copper/m3 sprayed at 14 day intervals as well as 42 mg/m3 every 21 days are the most cost-effective for joint management of citrus canker and black spot to be used in areas where both diseases are endemic and cause considerable yield losses. [ABSTRACT FROM AUTHOR]

Scorpionism is a major public health problem in Brazil. Although there is no known effective method for controlling these animals, a common practice in urban areas of the country is the use of insecticides such as Fipronil. Thus, the objective of the present study was to evaluate the effectiveness of fipronil-based insecticides in the control of Tityus stigmurus scorpion species. We specifically investigated the relationship between insecticide treatment duration, scorpion body mass, and mortality rate. The scorpions were divided into groups (n = 30) and exposed to insecticide-treated surfaces at different time intervals after application. Groups of animals subjected to surfaces within 3 h after application of the insecticide showed symptoms of intoxication and higher mortality. The groups with individuals that had contact with treated areas 24 h after insecticide application did not show any adverse reactions during the observation period. Our results suggest that the insecticide Fipronil may be effective in controlling T. stigmurus if animals come in contact within 3 h of product application. [ABSTRACT FROM AUTHOR]

We evaluated the lethal and sublethal effects of azoxystrobin, cyhalofop-butyl, and thiamethoxam on Telenomus podisi after spraying rice plants in a greenhouse, as well as the degradation kinetics of these compounds over time. Pesticides were sprayed at 50 and 100% of the maximum field recommended concentration for the crop (MFRC). At 0, 5, 10, and 20 days after application of the treatments (DAAT), T. podisi was exposed to leaves containing dry pesticide residues. On these same dates, rice leaves from each treatment were collected for determination of pesticide residues by UHPLC–MS/MS. Based on the results for mortality, parasitism, emergence, and sex ratio of T. podisi, the effects were grouped using a reduction coefficient (Ex) and classified according to the scale of the International Organization for Biological and Integrated Control (IOBC). The fungicide azoxystrobin (at 50 and 100% MFRC) was the only one classified as harmless (Class 1). The herbicide cyhalofop-butyl was classified as slightly harmful (Class 2) to T. podisi until 5 DAAT. The insecticide thiamethoxam (50 and 100% MFRC), up to 5 DAAT, was classified as harmful (Class 4) on T. podisi. Regarding residue, the initial concentrations (0 DAAT) of azoxystrobin, cyhalofop-butyl, and thiamethoxam at 100% MFRC in rice leaves were 102.14, 210.09, and 36.93 mg kg−1, respectively. At 50% MFRC, initial waste was approximately half that extracted at 100% MFRC. The estimated half-lives (DT50) were approximately 17, 4, and 5 days for azoxystrobin, cyhalofop-butyl, and thiamethoxam, respectively. Furthermore, we found a positive correlation between effects and residues. [ABSTRACT FROM AUTHOR]

Stink bugs (Hemiptera, Pentatomidae) are major pests of soybean [Glycine max (L.) Merr.]. Biological control agents do not always succeed in reducing stink bug populations, so it become necessary to expand insecticides knowledge for integrated pest management. We evaluated the effectiveness of thiamethoxam + lambda-cyhalothrin, imidacloprid + beta-cyfluthrin, acetamiprid + cypermethrin, imidacloprid + carbaryl, trichlorfon, thiamethoxam, imidacloprid and spirotetramat + thiamethoxam for the control of phytophagous stink bugs and their side effects on generalist predators. Additionally, we determined the toxicity of the same set of insecticides on the egg parasitoid Telenomus podisi (Ashmead). The effectiveness of pest control and impact on predators was evaluated in field trials on small soybean plots during the 2011–12 and 2012–13 growing seasons. The adverse effects of insecticides on the emergence of T. podisi parasitized eggs of the red-banded stink bug Piezodorus guildinii (Westwood) were tested under laboratory and field conditions. During the two assessed years, P. guildinii was the predominant Pentatomidae species and spiders were the most frequent predators followed by several species of Heteroptera and Coccinellidae which feed on a wide range of insects. Thiamethoxam + lambda-cyhalothrin provided the highest level of control of stink bugs, but negatively affected predators. Under laboratory conditions, mortality of developing T. podisi larvae was significantly higher when exposed to trichlorfon, imidacloprid + carbaryl and neonicotinoids/pyrethroids combintaions. In contrast, no treatment affected T. podisi emergence under field conditions. Results suggest that under natural conditions, insecticidal sprays at recommended rates for stink bugs control do not affect T. podisi larvae but a mixture of thiamethoxam + lambda-cyhalothrin negatively affects generalist predators. [ABSTRACT FROM AUTHOR]

Determining the effects of pesticides on all life stages of natural enemies is essential within Integrated Pest Management (IPM) programas, as an aid to minimize non-target effects and preserve beneficial insects. This study evaluated the selectivity and effects of pesticide residues on adults of the egg parasitoid wasp Telenomus podisi and its immatures when host eggs were treated. Fungicides, insecticides, and adjuvants were tested at field rates along with distilled water as a control. Based on parasitoid mortality and rate of parasitism, the products were assigned to four classes: 1, harmless (<30%); 2, slightly harmful (30-79%); 3, moderately harmful (80-99%) and 4, harmful (> 99%). For adult T. podisi exposed to pesticide residues, all treatments were harmless when evaluating parasitism rate except thiamethoxan + lambda-cyhalothrin (Class 3). Pyriproxyfen (Class 2) and thiamethoxan + lambda-cyhalothrin (Class 3) were harmful to the viability of T. podisi that emerged from parasitized eggs, while the other treatments were harmless. Azoxystrobin (Class 1), fluxapyroxad + pyraclostrobin (Class 1), pyriproxyfen (Class 1) and water (Class 1) were innocuous to the viability of T. podisi larvae in parasitized eggs that were exposed to pesticides. Treatment exposure reduced adult female longevity from a maximum of 23 days (teflubenzuron) to a minimum of 1 day (chlorpyrifos). The lifespan of the females treated while in host eggs ranged from 7 days (pyriproxyfen) to 14 days (water). Overall, the pesticides tested pose the most risk to emerged adult T. podisi and pose less threat when parasitoids are protected inside host eggs. [ABSTRACT FROM AUTHOR]

Mortality of agricultural pests caused by arthropod predators is a valuable ecosystem service for crop production. The earwig, Euborellia annulipes (Lucas), attacks different pest species in various crop ecosystems, including larvae and pupae of the boll weevil, Anthonomus grandis grandis (Boh.). In this study, multiple factors were assessed to measure the selectivity of insecticides used against sap-sucking and chewing cotton pests for two E. annulipes populations. Nymphs and adults of E. annulipes were exposed to the insecticides in two ways: ingestion of contaminated prey, and contact with dried residues on either inert surfaces or treated plants bearing prey. Pymetrozine, chlorantraniliprole, and spinetoram had little effect on the predator regardless the tested earwig population, life stage with developmental time and survival, or the route of exposure (ingestion and residual). Cyantraniliprole dried-residue impeded nymph to complete development and only 27% of adults survived until 20 days after exposure. Pyriproxyfen was harmless through acute toxicity to nymphs and adult earwigs (70–100% survival 72 h after exposure), but prevented normal development of nymphs to adults causing chronic toxicity. Chlorfenapyr, indoxacarb, lambda-cyhalothrin, chlorpyrifos, dimethoate, and malathion were harmful to the predator regardless life stage or method of exposure. The negative impact of thiamethoxam, lambda-cyhalothrin and indoxacarb was diminished when exposure occurred on plants with predator allowed to shelter in the soil. The results indicate that insecticide selectivity outcome varies by the insecticide, predator life stage and the predator's behavior. Therefore, testing different predator life stages via several routes of exposure, without denying the insect the opportunity to engage in its normal behavior can provide better estimates of insecticide selectivity. [ABSTRACT FROM AUTHOR]

The South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), has invaded most Afro-Eurasian countries and is threatening worldwide tomato production. Various strategies have been developed and implemented to manage this pest. Here, we present a timely review on the up-to-date development and practical implementation of integrated pest management (IPM) programs for tomato crops across different world regions infested by T. absoluta. While insecticide resistance is a growing concern, biological control via releasing or conserving arthropod natural enemies and sex pheromone-based biotechnical control are the most successful management practices. Agronomic control-related research is an emerging area where the soil fertilization and/or irrigation, as well as breeding of resistant cultivars, has the potential to enhance IPM effectiveness. Grower survey responses in the native areas (i.e., South America), early-invaded areas (i.e., first report between 2006 and 2012) and newly invaded areas (i.e., first report after 2012) showed that the control programs evolved along with the areas and time since invasion. Growers in the early-invaded areas shifted more rapidly from chemical control to biological control compared to those from the native area. In all concerned regions, the pest control failure risk following chemical insecticide applications and the high cost associated with either biological or biotechnical control methods have been the greatest concerns for growers. The information gathered from the native and/or early-invaded areas may help achieve a more effective management in newly invaded areas. Lastly, researchers are expected to break the bottlenecks of some key issues that would enable lowering application cost of novel biorational alternative management options. [ABSTRACT FROM AUTHOR]

The appearance and rapid spread of the fall armyworm (Spodoptera frugiperda) (FAW) represents a serious threat to maize cultivation in India and elsewhere in South Asia. Chemical control illustrates one of the major means of reducing the infestation of FAW in maize-growing zones. However, existing information regarding the field-efficacy and non-target toxicity of different insecticides against this pest is not adequate and is also unable to capture the momentum change in the scenario of residual toxicity and insecticide resistance for redacting sustainable management. The present study was framed to establish the most suitable insecticidal schedule against FAW for maize producers. In the period from winter 2019–2020 to spring–summer 2020, seven treatment schedules against FAW were evaluated, and the efficacy was calculated according to the per cent maize plant damage (PD) by larvae, while safety was enumerated based on larval parasitization by Campoletis chlorideae and the abundance of coccinellid predators. In both seasons, the highest cumulative efficacy (9.88 and 10.19% PD) was confirmed for T3 (constituted with Barazide®, Delegate®, and Ampligo®) with a significantly higher yield (52.39 and 52.66 q ha−1), whereas T7 (Proclaim Fit®, Ampligo®, and Delegate®) and T6 (Fimecta®, Ampligo®, and Spintor®) exhibited a high cumulative efficacy (11.06 to 12.23% PD). T3 was found to be safe to coccinellid predators and the per cent larval parasitism by C. chlorideae was significantly higher in this module (2.57 and 2.75%) compared to T4 and T5 (1.00 to 1.67%). The residues of Barazide®, Delegate®, and Ampligo® were below detectable levels in maize plant, grain and soil samples. Therefore, the module could be recommended against FAW in the near future. [ABSTRACT FROM AUTHOR]

The olive leaf gall midge (Dasineura oleae) is a gall-inducing insect on leaves, branches and stems of flowers of olive trees. Heavy infestation with the insect causes significant reduction in olive production. The outbreak of the insect occurs in various local regions of olive production in the Mediterranean countries since 2010 causing serious damage on infested trees. No previous revisions have been made on the control measures of D. oleae, and no specific integrated control programs of this insect were implemented to manage the insect outbreak. Therefore, the present review aimed at, first, revising and discussing the research conducted on the control measures of D. oleae and then suggesting a specific integrated control program for a better management of this insect during the outbreaks. The suggested program is mainly relying on biological control of D. oleae using native parasitoids as the main component. The other components of the program (e.g., using yellow sticky traps, pruning infested olive organs with the insect then burning them, and irrigating trees properly during the hot months of summer and fall seasons) should be applied if the suppression of the insect population by the native parasitoids is not enough. This review discusses the potential implementation of the suggested program and provides some conclusions and recommendations for guiding and improving the future research on this pest. [ABSTRACT FROM AUTHOR]

The overuse of insecticides to control vector insects such as Diaphorina citri Kuwayama in citrus groves has altered the population dynamics of pest mites. Among phytophagous mites, population outbreaks of citrus leprosis mite, Brevipalpus yothersi Baker, have been increasingly intense and frequent in Brazilian citrus groves. Despite the great importance of the B. yothersi mite for citrus production, the lethal and sublethal effects of insecticides on this mite have not yet been studied. Therefore, in this study, the effects of insecticides commonly used for D. citri control on B. yothersi mortality, reproduction, and instantaneous growth rate were assessed. For this, two experiments were carried out, one under controlled conditions and another in a greenhouse. The insecticides tested were beta-cyfluthrin, bifenthrin, buprofezin, chlorpyrifos, dimethoate, pyriproxyfen, and thiamethoxam at 0 (control), 0.0625, 0.125, 0.25, 0.5, 1, and twofold the recommended insecticide concentration for D. citri control. The pyriproxyfen insecticide provided high mortality of B. yothersi even at low concentrations. Furthermore, this insecticide negatively interfered with the reproduction of this mite. Beta-cyfluthrin, bifenthrin, buprofezin, chlorpyrifos, dimethoate, and thiamethoxam, in the tested concentrations, showed low impact on citrus leprosis mite. Regarding the reproduction of the mite, no significant increase in fecundity was observed on B. yothersi females exposed to insecticide residues, regardless of the concentration tested. Therefore, the application of these insecticides in the management of pest insects is unlikely to promote an increase in the citrus leprosis mite population. [ABSTRACT FROM AUTHOR]

The whiteflies of the Bemisia tabaci (Genn.) complex (Hemiptera: Aleyrodidae) are serious agricultural pests that cause severe losses to vegetable, ornamental and fiber crops, including potato plants, mainly as a vector of economically important viruses. Among the most important viruses affecting potato is tomato chlorosis virus (ToCV) (Closteroviridae: Crinivirus), which is semi-persistently transmitted by whiteflies of the genera Bemisia and Trialeurodes. Chemical control is the main method used to manage B. tabaci and ToCV; however, this whitefly is resistant to most commercially available insecticides, and some products may not effectively prevent the vector stylet activities associated with virus transmission. The effective management of B. tabaci is crucial to reduce the spread of vector-borne diseases, and to minimize economic losses. We evaluated the effects of the foliar spraying with the systemic insecticides acetamiprid, flupyradifurone and cyantraniliprole on the probing behavior of non-viruliferous and ToCV-viruliferous B. tabaci MEAM1 and ToCV transmission in potato plants. To evaluate ToCV transmission in greenhouse conditions, viruliferous whiteflies were released on potato plants at different time points (3, 24 and 72 h and 7 days) after insecticide spraying. The EPG assay showed that at 3 h after insecticide application, the probing behavior differed, depending mainly on the state of the insects (viruliferous or not), whereas 72 h after application, the probing behavior differed only on plants treated with acetamiprid and flupyradifurone, for both viruliferous and non-viruliferous whiteflies. ToCV transmission was reduced mainly in plants treated with flupyradifurone and acetamiprid, likely as a result of phloem activity disruption. [ABSTRACT FROM AUTHOR]

This study aimed to compare the susceptibility of tomato pinworm, Tuta absoluta, from four Brazilian regions to insect growth disruptor (IGD) insecticides by tomato leaf-dip bioassays. Larval mortality was assessed seven days after exposure to insecticide-treated leaves. The control failure likelihood (CFL) was estimated after larval bioassays with IGDs recommended label rate. Mortality data were subjected to Probit and variance analysis. All populations of tomato pinworm showed significant resistance to one or more insecticides. The LC50 values ranged from 0.34 to 0.63 g L−1 (chlorfluazuron), 0.17 to 0.92 g L−1 (teflubenzuron), 0.13 to 1.28 g L−1 (novaluron), 0.29 to 0.46 g L−1 (lufenuron), and 0.71 to 4.60 g L−1 (methoxyfenozide). The resistance ratios varied from 1.2 to 1.8-fold (chlorfluazuron), 1.4 to 5.5-fold (teflubenzuron), 1.2 to 9.9-fold (novaluron), 1.0 to 1.6-fold (lufenuron), and 1.5 to 6.5-fold (methoxyfenozide). Despite the low resistance ratios (< 10-fold), all populations showed low mortality and CFL > 54%, indicating likely control failure at the IGD label rates. We detected significant variations among populations of T. absoluta for activity of enzymes glutathione S-transferases (GST), cytochrome P450-dependent monooxygenases (MFO) and α-esterase (EST), however there was no significant difference between the populations for activity of β-esterase (EST). The evolution of resistance in T. absoluta populations to IGDs observed in this study is likely due to high selection pressure, demanding insecticide resistance management practices and environmentally sustainable tactics to obtain a more effective control of this pest. [ABSTRACT FROM AUTHOR]

Meloidogyne graminicola is responsible for large yield losses in flooded rice, a problem that is mainly associated with the limited efficacy of nematode management tactics. This study aimed to assess the efficiency of different products applied by seed treatment in controlling M. graminicola in flooded rice grown from polymer-coated and uncoated seeds. Greenhouse experiments were designed to investigate treatment effects on nematode reproduction, root penetration, and plant vegetative parameters, and in vitro assays were used to assess treatment effects on egg hatching and juvenile mortality. Treatments were as follows: Wollastonite (calcium silicate), Agrosilicon (calcium and magnesium silicate), NemOut™ (Bacillus licheniformis + Bacillus subtilis + Trichoderma longibrachiatum), CompostAid® (Lactobacillus plantarum + B. subtilis + Enterococcus faecium), NemaControl® + StimuControl® (Bacillus amyloliquefaciens + Trichoderma harzianum), Nim-I-Go® (Azadirachta indica oil), Avicta 500 FS (abamectin), and CropStar® (thiodicarb + imidacloprid). Inoculated and uninoculated controls were also included. Avicta 500 FS, CropStar®, NemOut™, and CompostAid® were the most effective in reducing nematode penetration and number of nematodes per gram of root. The best in vitro results were obtained with Avicta 500 FS, CropStar®, NemOut™, and CompostAid®. Only Wollastonite showed no in vitro nematicidal activity. Most treatments also improved vegetative growth. It was concluded that treatment of rice seeds with chemical or biological products is effective in controlling M. graminicola. [ABSTRACT FROM AUTHOR]

White mango scale, Aulacaspis tubercularis Newstead (Hemiptera: Diaspididae), is one of the most damaging pests of mango crops around the world, causing conspicuous pink blemishes on ripe fruits that reduce their commercial value. This research aims to determine the seasonal trend of this invasive pest in Southern Spain as a first step to develop an integrated pest management program. Periodic sampling in two mango groves from June 2013 to December 2015 showed that A. tubercularis completed four overlapping generations annually. Pest density started to increase in spring (mid-May), reaching the highest pest population levels in summer (mid-August) and early autumn (mid-October), corresponding with the ripening and harvesting periods, respectively. Aulacaspis tubercularis was mostly found on the upper leaf surface, although the pest was also located on the lower leaf surface. Fruit became infested by crawlers of the first generation during the early fruit development period and the scale was more abundant during the ripening period. In addition, the efficacies of four reduced-risk insecticides were tested at commercially recommended field rates on nymphs and adults of A. tubercularis in mango trees. Fourteen days after the treatment, paraffin oil at 1.25% was the most effective insecticide (90.87%) for both scale stages, followed by diatomaceous earth (77.18%), azadirachtin (69.32%) and paraffin oil at 0.75% (46.24%). These results will improve field sampling protocols and facilitate the development of integrated pest management programs based on the conservation of natural enemies combined with paraffin oil applications in spring before the scales migrate to the fruit. [ABSTRACT FROM AUTHOR]

Copper sprays are the most important measure for control of citrus canker. Mechanical wounds caused by cultural practices are entry points for the causal bacterium, Xanthomonas citri subsp. citri, and exacerbate the disease. It is not known whether additional applications would protect mechanical wounds from infection by X. citri. This study aimed to assess the predisposition of mechanical wounds to infection and the efficacy of a single copper spray applied at different times for protecting wounds against X. citri under greenhouse conditions. Access of wounds to infection was assessed by spray-inoculating a suspension of the bacterium on leaves from 0 to 7 days after wounding. Timing of a copper application was assessed by treating the wounded leaves at different points before or after bacterial inoculation and/or wounding. The incidence of wounds with citrus canker decreased over time after wounding. No lesions developed in wounds inoculated 7 days after injury. Copper sprayed at all timings reduced the incidence of citrus canker at wound sites compared to the non-treated leaves. Copper sprayed before wounding and/or inoculation showed the greatest reduction (>90%) in the incidence of citrus canker. The reduction in canker associated with wounds ranged from 91.8 to 96.1% for copper sprays applied from 24 h before to 0.5 h after wounding and inoculation, and was 67.8% when copper was applied up to 8 h after wounding and inoculation. As X. citri is splash-dispersed, we conclude that wounds need to be protected with copper sprays if rain is forecast within 7 days of a wounding event. In case no rain is expected, there is no need to protect the trees with copper. However, if trees are wounded when the canopy is wet, a copper spray should be applied before or immediately after the wounding event (but not more than 8 h later). A single appropriately timed copper spray allows the protection of wounds against citrus canker even after the tissue is injured. [ABSTRACT FROM AUTHOR]

Harmful algal blooms negatively impact water quality in hypereutrophic systems that are common in aquaculture. However, few algaecides are approved for use in food-fish aquaculture. This study assessed the effectiveness of seven products, including hydrogen peroxide (as a concentrated liquid or in granular form (PAK-27)), peracetic acid (as VigorOx SP-15 and Peraclean), copper (as copper sulfate in unchelated (powder) or chelated (Captain) forms), and a clay-based product (as Phoslock) on phytoplankton (including cyanobacteria) and zooplankton biomass. Each product was tested in a 14-day laboratory and 35-day field experiment to assess their short- and long-term performance. Although some products (i.e., copper-based and liquid hydrogen peroxide) quickly reduced phytoplankton, effects were short-lived given that chlorophyll concentrations returned to starting concentrations within 21 days. In contrast, all but one product (i.e., concentrated liquid hydrogen peroxide) maintained low phycocyanin concentrations for 35 days. Zooplankton biomass trends showed large, negative effects for most algaecides; however, zooplankton rebounded for most treatments except for copper-based products. In general, copper-based products remain the most efficient and cheapest choice to reduce total phytoplankton biomass in aquaculture systems. However, peracetic acid-based products effectively and quickly reduced cyanobacteria while having marginal effects on beneficial algae and zooplankton. Such algaecides could be effective alternatives to copper-based products for aquaculture farmers. [ABSTRACT FROM AUTHOR]

There is increasing concern about the toxic effects of chemical pesticides on human health and the environment. Many alternatives, however, are viewed as impracticable or inefficient for agricultural needs. Here, a sustainable, environmentally friendly strategy was designed for the control of major rice insect pests (i.e. Nilaparvata lugens, Cnaphalocrocis medinalis and Chilo suppressalis) with minimal impact on natural enemies via selection of a specific entomopathogenic fungal strain for use as a biological control agent. In large-scale multiyear field applications, Metarhizium anisopliae CQMa421 was shown to act as effectively as chemical pesticides for pest control. Rice pest control applications in all major rice-producing provinces in China covering > 6000 hectares, performed over a period of 8 years (2011–2018), showed equal rice harvest yields between the use of the fungal pathogen versus chemical pesticides. More importantly, the use of the specific fungal pathogen isolated by this strategy resulted in an increase in beneficial insects and other animals. These long-term field evaluation data and large-scale application results demonstrated the feasibility of shifting from chemical dependency to more nuanced approaches for pest control for maintaining agricultural productivity while protecting natural enemies. With this strategy, new specific fungal strains can also be isolated to control the main pests of other crops. [ABSTRACT FROM AUTHOR]

Orange rust (OR) and brown rust (BR) are among the most important diseases of sugarcane. The objective of this work was to evaluate the efficiency of fungicides in the control of both rusts. Two experiments, one for each rust, were conducted in the state of Paraná, Brazil, in plant cane and in ratoon. A randomized block design with 8 treatments and three replications was used. The treatments were: control (T1), pyraclostrobin (T2), pyraclostrobin + epoxiconazole (T3), azoxystrobin + cyproconazole (T4), azoxystrobin + tebuconazole (T5), trifloxystrobin + tebuconazole (T6), azoxystrobin + benzovindiflupyr (T7) and pyraclostrobin + fluxapyroxad (T8). The cultivars RB72454 and RB835486 were used for their susceptibility to OR and BR, respectively. Four applications of fungicides were carried out in plant cane and also in ratoon, in a 30-day intervals. With the severity data over time, the relative area under the disease progress curve (rAUDPC) was calculated. After harvest, yield (tons of cane per hectare-TCH), yield recovery compared to the control (YR) (%), pol% cane (PC) and tons of pol per hectare (TPH) were obtained. From rAUDPC results, treatments T3, T4, T5, and T7 were the most efficient for the control of OR and treatments T2, T3, T4, T5, T7 and T8 were the most efficient for controlling BR. Yield was affected by treatments only in ratoon in both experiments. The YR ranged from 18.5% to 31.1% and from 16.1% to 37.7% to OR and BR, respectively. There were no differences between treatments for PC in both experiments and TPH was influenced by treatments in ratoon in the BR experiment. [ABSTRACT FROM AUTHOR]

Although freshwater invasions have not been targeted for maintenance management or eradication as often as terrestrial invasions have, attempts to do so are frequent. Failures as well as successes abound, but several methods have been improved and new approaches are on the horizon. Many freshwater fish and plant invaders have been eliminated, especially by chemical and physical methods for fishes and herbicides for plants. Efforts to maintain invasive freshwater fishes at low levels have sometimes succeeded, although continuing the effort has proven challenging. By contrast, successful maintenance management of invasive freshwater plants is uncommon, although populations of several species have been managed by biological control. Invasive crayfish populations have rarely been controlled for long. Marine invasions have proven far less tractable than those in fresh water, with a few striking eradications of species detected before they had spread widely, and no marine invasions have been substantially managed for long at low levels. The rapid development of technologies based on genetics has engendered excitement about possibly eradicating or controlling terrestrial invaders, and such technologies may also prove useful for certain aquatic invaders. Methods of particular interest, alone or in various combinations, are gene-silencing, RNA-guided gene drives, and the use of transgenes. [ABSTRACT FROM AUTHOR]

The red imported fire ant Solenopsis invicta Buren (Hymenoptera: Formicidae), is a serious invasive alien ant around the world and has expanded its invasive range to the Pacific Rim since the early 2000s. It was first reported in Japan in 2017, and its entry through cargo has been reported numerous times in many ports. Colonies have been found in Tokyo Port since 2019, and now it is an urgent issue to prevent further invasion and establishment. Chemical control is the best tested method of insect control, but we have little information on the efficacy of insecticides against S. invicta in Japan. Here, we conducted acute toxicity assays of six quick-acting pyrethroids (transfluthrin, prallethrin, phenothrin, permethrin, metofluthrin, and pyrethrin) for killing adults and five new-type insecticides (fipronil, thiamethoxam, indoxacarb, imidacloprid, and hydramethylnon) for controlling colonies with toxic baits. We found that the LD50 from six pyrethroids were comparable to each other. The ED50 causing abnormal behaviors were smaller than LD50, but some ants recovered from paralysis within 12 h. Fipronil showed the lowest LD50 suggesting this chemical is the most promising agent for controlling S. invicta. Our results promise to develop a method for the chemical control of S. invicta. [ABSTRACT FROM AUTHOR]

The frequency of Alzheimer's disease (AD) is growing rapidly with longer life expectancy and the consequent increase of people with a high risk of neurodegenerative diseases. Anacardic acid (AA) has several pharmacological actions, such as antioxidants, anticholinesterase, and anti-inflammatory, which are related to the protection against aging disorders. Also, the metals copper and zinc are co-factors of antioxidant enzymes that can be associated with AA to improve brain-protective action. This study aimed to evaluate the potential of AA metal complexes using copper and zinc chelators to produce potential agents against Alzheimer's disease. For this purpose, Cu and Zn were linked to AA in the ratio of 1:1 in a basic medium. The complexes' formation was confirmed by ultraviolet and visible spectroscopy. The toxicity was evaluated in the zebrafish model, and other information related to AD was obtained using the zebrafish model of anxiety. AA-Zn and AA-Cu complexes showed better antioxidant action than free AA. In the anti-AChE activity, AA was like the AA-Cu complex. In models using adult zebrafish, no toxicity for AA complexes was found, and in the locomotor model, AA-Cu demonstrated possible anxiolytic action. In in silico experiments comparing AA and AA-Cu complex, the coupling energy with the enzyme was lower for the AA-Cu complex, showing better interaction, and also the distances of the active site amino acids with this complex were lower, similar to galantamine, the standard anti-AChE inhibitor. Thus, AA-Cu showed interesting results for more detailed study in experiments related to Alzheimer's disease. [ABSTRACT FROM AUTHOR]

This article deals in a continuous Schistosomiasis transmission model involving hosts human and freshwater snail, and two free living Schistosoma larva forms Miracidia and Cercariae. Along with derivation of basic reproduction number and standard equilibrium analysis, Hopf bifurcation phenomenon is demonstrated analytically and numerically. Parameter sensitivity analysis of system solution has been used to identify significant parameters for the change of disease dynamics. Impulsive optimal control of the same system, adding combined biological and chemical control of snail population to minimize human infection is undertaken. Snail natural predator crayfish is used for biological control and molluscicide is used for chemical control, where both controls are released in water periodically for finite number of times. Mathematically, the continuous system is converted to a discrete-continuous hybrid control problem applying Pontryagin's Maximum Principle. The optimum solution revealed the quantity of each control to be released at each time point. The control analysis identified parameters crucial to success of combined control. [ABSTRACT FROM AUTHOR]

Application of control agents to prevent new infections is an integral part of disease management for fire blight on pome trees caused by Erwinia amylovora (Burrill) Winslow et al.. Due to resistance development and human health concerns when using antibiotics, non-antibiotic control agents with high efficacy are urgently needed. In this study extensive efficacy tests with some classical antibiotic and relatively new non-antibiotic control agents for the prevention of bloom and shoot blight as well as phytotoxicity tests based on fruit russeting were carried out using young apple trees. Furthermore an experimental design for testing control agents preventing fire blight following hail injury was developed. The high efficacy of streptomycin (> 90%) and streptomycin containing spray strategies (> 80%) was confirmed. Non-antibiotic agents with high efficacy are LMA (85%), a potassium aluminum sulfate, and Juglon (80%). LMA is already in use in practice in Austria and Germany with a temporal and restricted permission and the administrative process to gain the legal status of a pesticide is ongoing whilst already admitted in Switzerland. Juglon, an organic compound from walnut, did show a high efficacy, but no consistent results (80.0 and 69.5%). Myco-Sin showed good results to prevent infection after artificial hail simulation. Antinfek showed high efficacy (90%) in preventing bloom blight, but could be tested only once so further research is needed to confirm this result. The design of the presented study enabled an extensive evaluation of the potential control agents and the aggregation and comparison of results and can be advised for other evaluations. [ABSTRACT FROM AUTHOR]

This work aimed to evaluate the residual action of five insecticides on larvae and adults of the predators Chrysoperla externa (Hagen) and Eriopis connexa (Germar). The insecticides gamma-cyhalothrin, imidacloprid+beta-cyfluthrin, methomyl, thiamethoxam, and thiamethoxam+lambda-cyhalothrin were sprayed in pod bean plants until the point of runoff. Weekly, at 3, 10, 17, 24, and 31 days, first instar larvae and adults of both predators were exposed to leaves containing dry residues of the insecticides. Based on the mortality observed throughout the bioassays, the insecticides were classified according to the scale of the residual effects proposed by the International Organization for Biological and Integrated Control (IOBC). Except for thiamethoxam+lambda-cyhalothrin, which was moderately persistent (class 3) to larvae of C. externa and E. connexa, all other tested insecticides were persistent (class 4) to larvae of both species. Gamma-cyhalothrin, imidacloprid + beta-cyfluthrin, and methomyl were persistent (class 4) to C. externa adults, while thiamethoxam was moderately persistent (class 3) and thiamethoxam + lambda-cyhalothrin was slightly persistent (class 2) to the adult stage. As for E. connexa adults, imidacloprid + beta-cyfluthrin and methomyl were persistent (class 4) and gamma-cyhalothrin, thiamethoxam, and thiamethoxam + lambda-cyhalothrin were moderately persistent (class 3). Thus, due to extended residual effect, these insecticides must be avoided when larvae and adults of both predators are active in the crop. [ABSTRACT FROM AUTHOR]

Sugarcane is the main cash crop in Guangxi, China. Fall armyworm (FAW), Spodoptera frugiperda, is an invasive pest and has migrated to Guangxi since April 2019. FAW is spreading rapidly now and has distributed in over 18 provinces and municipals in China. Also FAW has been found to damage sugarcane seriously and is an urgent threat to sugarcane. In order to screen chemicals for effective FAW control, insecticides were sprayed by drone in field experiments. The results showed that the mixture of chlorfenapyr–chlorantraniliprole–lufenuron had the best control with 94.86% population decline rate with 94.94% control efficacy. The population decline rate and control efficacy of abamectin–chlorantraniliprole and chlorfenapyr–lufenuron were all over 80%. However, the treatment of abamectin–dursban had only 20.82% population decline rate and 21.85% control efficacy. Therefore, the spray of insecticide mixture of chlorfenapyr–chlorantraniliprole–lufenuron through drone would be recommended for FAW control. [ABSTRACT FROM AUTHOR]

Liothrips wasabiae Haga & Okajima (Thysanoptera: Phlaeothripidae) is an important pest insect infesting wasabi (Eutrema japonicum syn. Wasabia japonica) but effective control methods are still missing. Therefore, we investigated the host range of L. wasabiae and the efficacy of chemical and biological insecticides and a physical control method (insect nets) against it. Adult thrips could not pass through nets of 0.3-mm mesh but could pass through nets of 0.4-mm mesh. The lifespan of adults reared on leaf mustard (Brassica juncea), rocket (Eruca vesicaria), and daikon (Raphanus sativus) was significantly longer compared with that of adults reared on water only (control). In host plants where feeding was longer, adult lifespan tended to be longer. The insecticides dinotefuran, nitenpyram, ethiprole, and Beauveria bassiana emulsifiable concentrate resulted in high mortality of L. wasabiae. By contrast, the mortality of B. bassiana wettable powder and pymetrozine was relatively low. Our results revealed the optimal mesh size of insect nets for suppressing invasion, the suitable hosts for long-term survival, and the efficacy of insecticides for controlling L. wasabiae. These results contribute to the development of methods to restrict the expansion and to manage the population density of L. wasabiae. [ABSTRACT FROM AUTHOR]

Brown leaf spot (BLS), caused by the fungus Clarohilum henningsii, is one of the most common leaf diseases in cassava, leading to losses in root yield due to the extensive defoliation of the plants. Despite this, BLS has been neglected and little is known about the disease. This study aimed to evaluate the ability of systemic fungicides (cyproconazole, thiophanate-methyl, pyraclostrobin, tebuconazole, azoxystrobin, and flutriafol) to inhibit the in vitro growth of C. henningsii isolates and to control BLS in cassava plants. In addition, we verified the effect of the fungicides on the plant physiology by measuring the chlorophyll a content. The results showed that the isolates were sensitive to all fungicides, as demonstrated by the low EC50 (effective concentration of fungicide able to inhibit mycelial growth by 50%) values, which ranged from 0.06 to 0.43 μg.mL−1. In addition, all fungicides were able to reduce the severity of BLS in cassava plants, but with different effectiveness. In general, flutriafol had the highest efficiency in reducing the disease severity under greenhouse and field conditions. Cassava plants treated with pyraclostrobin, azoxystrobin, and flutriafol had the highest increase of chlorophyll a content, which has not been reported in this crop. Based on our results, flutriafol is the most promising fungicide to control BLS in cassava, since it had the highest effectiveness in reducing the disease and provided the highest increase in the chlorophyll a content of the plants. [ABSTRACT FROM AUTHOR]

Chrysoperla externa and Coleomegilla quadrifasciata are important biological control agents in peach orchards. However, orchard management with these predatory insects is viable only by using selective agrochemicals. The objective of this study is to evaluate the toxicity of nine agrochemicals used in peach orchards in larval and adult stages of the C. externa and C. quadrifasciata in laboratory conditions. The bioassays followed the methodologies proposed by the International Organization for Biological and Integrated Control (IOBC). Larvae and adults of C. externa and C. quadrifasciata were exposed to the dry residues of these products. Lethal and sublethal effects were evaluated in bioassays with the larval and adult stages of both predators. The agrochemicals were classified according to the IOBC guidelines. The insecticide chlorantraniliprole was harmless (class 1) to the larval stage of C. externa and C. quadrifasciata. Azadirachtin, copper 25% + calcium 10%, and deltamethrin were harmless to the adult stage of both insect species. The organophosphates fenitrothion and malathion were harmful (class 4) to both species in the larval and adult stages and should not be used in peach orchards. Therefore, this study demonstrates the importance of toxicity and the lethal and sublethal effects of these agrochemicals to better determine their compatibility with IPM in peach production. [ABSTRACT FROM AUTHOR]

Sweet pepper is an important vegetable crop in Egypt. It is cultivated for local consumption and exportation. The crop is attacked by a large number of pest species such as Western flower thrips, Frankliniella occidentalis (Pergande), whitefly, Bemisia tabaci (Genn.), the two-spotted spider mite, Tetranychu surticae Koch, and the beet armyworm, Spodoptera exigua (Hubner). The present study was conducted on the sweet pepper cultivated in greenhouses, during the winter plantation 2016/17 in a commercial farm located at Berkash district, Giza Governorate, Egypt. Three control programs were practiced: the first used biological control agents (BC), the predators, Orius albidipennis (Reuter), Macrolophus caliginosus (Wagner), Chrysoperla carnea (Steph.), and the egg parasitoid, Trichogramma euproctidis (Girault); the second was sprayed by the recommended chemical control program of the farm (CC); and the third was untreated as a control. Obtained results revealed that the BC program was the most significant one for controlling the complex of sweet pepper pests. Also, applying the BC program resulted to a high yield of sweet pepper production (35.06% increasing than the control). [ABSTRACT FROM AUTHOR]

One of the objectives of integrated production (IP) are rationalizing the use of pesticides. For conilon coffee (Coffea canephora), a coffee leaf rust (Hemileia vastatrix) management system based on IP principles needs to be proposed and validated. Thus, this study aimed to quantify the economic and environmental effects of rust management based on disease monitoring for decision-making regarding fungicide use in conilon coffee (integrated coffee production, ICP-Conilon). The ICP-Conilon system was compared with the conventional rust management system (CS) based on a fixed schedule of fungicide application by delineating two plots of C. canephora clonal fields. The incidence of leaf rust in the plants from each clone was quantified monthly and, in the ICP-Conilon plots, systemic fungicide was applied only to the clones/planting rows with monthly disease incidence of ≥5%. The ICP-Conilon system resulted in an average reduction of 71.3% in the fungicide volume applied/ha/year, compared to that in the CS plots. Thus, it was possible to reduce, on average, 21% of the rust management cost in clonal conilon coffee plantations. [ABSTRACT FROM AUTHOR]