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Ceratitis capitata is considered the key pest of fruit production worldwide, due to its wide host variety. As an alternative control method for this pest, the objective of this research was to evaluate the repellency of C. capitata to liquid biofertilizers added to plant extracts. The repellency was evaluated through olfactory arenas, using the biofertilizer Vairo and the plant enrichment, diluted in distilled water at 10% and added in equal parts with plant extracts of neem, pitanga and rue at concentrations of 30, 40 and 50% p/v. The larval infestation index was evaluated from the fruits used in the repellency bioassay. The addition of plant biofertilizer and neem extract at 30% w/v showed the highest repellency index for C. capitata, resulting in only 1.6% of visiting flies. The lowest rate of larval infestation was observed in the Vairo biofertilizer + rue extract and in the plant biofertilizer + neem at concentrations of 30 and 40% w/v, with averages of less than one larva/fruit. Vairo biofertilizer + neem extract and plant biofertilizer + pitanga reduces the number of adult insects in fruits and Vairo biofertilizer + rue extract and plant biofertilizer + neem reduces the number of C. capitata larvae in treated fruits. The addition of biofertilizers to the plant extracts analyzed influences the repellency and larval incidence of C. capitata when the fruits are treated with these mixtures. [ABSTRACT FROM AUTHOR]

Abstract Background Injectable radioactive iodine (I‐131) frequently is used to treat hyperthyroidism in cats. In human medicine, residual activity after injection of radionuclides has been reported, and the actual quantity administered is recorded after administration. Objective Our aim was to evaluate actual administered dose variability after administration of preprepared I‐131 single unit doses for the treatment of hyperthyroidism in cats. Animals Twenty‐seven cats with hyperthyroidism treated with I‐131 between April 2017 and March 2019. Methods Retrospective observational study of cats treated with preprepared single unit I‐131 doses. For each dose, the measured activity before administration and residual activity were recorded. The measured dose and the actual dose administered were compared to the prescribed dose. Results Measured activity before administration ranged from 88.4% to 103.3% of the prescribed dose. Mean residual activity was 5.2 ± 3.0 MBq (ranging from 1.5% to 15% of the prescribed dose). The actual dose administered (measured activity − residual activity) ranged from 79.1% to 100.2% of the prescribed dose. Seventeen of 28 (60.7%) of the actual administered doses differed between 10% and 20% of the prescribed dose. One administered dose had a >20% difference compared to the prescribed dose (79.10% of the prescribed dose). Conclusion and Clinical Importance Our study identified variability in the residual and actual administered activity of I‐131 as compared to the prescribed dose, which should be taken into consideration when treating cats with (predrawn) I‐131.

Plant lipases are highly versatile biocatalysts due to their chemo-selectivity, enantio-selectivity, and region-selectivity. The purpose was to obtain a recyclable biocatalyst from Pachira speciosa seed lipases, applicable to lipid bioconversion. A partially purified lipase was obtained from P. speciosa seed extracts, by gel filtration chromatography on Sephadex G-100; the specific lipase activity (LAS) was determined by free fatty acid titration. A Box-Behnken response surface design was applied to establish conditions that maximize lipase immobilization to three supports: chitosan beads (Ch), calcium alginate beads coated with chitosan (Alg- Ch), and chitosan-Fe(OH)3 magnetic beads (Ch-Fe). The highest LAS of the free enzyme was 8,23 ± 0,23 nKat/mg of protein at 40 °C and pH 9. The immobilization percentage and LAs (nKat/mg of beads) of each biocatalyst was EQ = 90,6 % and 3,74 ± 0,3 nKat/mg; Alg-Q = 88,5 % and 3,62 ± 0,1 nKat/mg; EQ-Fe = 76,4 % and 2,88 ± 0,1 nKat/mg. The most stable biocatalyst was the lipase immobilized in Ch, with 85 % retention of LAS until the third catalytic cycle. Future studies will be focused on establishing the kinetic parameters of the biocatalyst. [ABSTRACT FROM AUTHOR]

Shielding of a neutron source housing for 1 Ci 241Am-Be source has been designed and fabricated based on the simulation carried out using Monte Carlo code FLUKA. Neutron and photon dose equivalent rates at the surface and at 1 m distance from the surface of the housing were calculated using FLUKA simulation and measured using gamma and neutron dose rate meters. The calculated and measured gamma and neutron dose equivalent rates agree well. Neutron spectra outside the source housing were generated using FLUKA simulation and measured with the ROSPEC + simple scintillation spectrometer neutron spectrometry system and also agree reasonably well. Gamma spectra outside the source housing and residual activity due to activation products in stainless steel and lead of the housing were also generated through simulation.

Abstract Background Accurate determination of the efficacy of antimicrobial agents requires neutralization of residual antimicrobial activity in the samples before microbiological assessment of the number of surviving bacteria. Sodium polyanethol sulfonate (SPS) is a known neutralizer for the antimicrobial activity of aminoglycosides and polymyxins. In this study, we evaluated the ability of SPS to neutralize residual antimicrobial activity of antimicrobial peptides [SAAP-148 and pexiganan; 1% (wt/v) in PBS], antibiotics [mupirocin (Bactroban) and fusidic acid (Fucidin) in ointments; 2% (wt/wt))] and disinfectants [2% (wt/wt) silver sulfadiazine cream (SSD) and 0.5% (v/v) chlorhexidine in 70% alcohol]. Methods Homogenates of human skin models that had been exposed to various antimicrobial agents for 1 h were pipetted on top of Methicillin-resistant Staphylococcus aureus (MRSA) on agar plates to determine whether the antimicrobial agents display residual activity. To determine the optimal concentration of SPS for neutralization, antimicrobial agents were mixed with PBS or increasing doses of SPS in PBS (0.05–1% wt/v) and then 105 colony forming units (CFU)/mL MRSA were added. After 30 min incubation, the number of viable bacteria was assessed. Next, the in vitro efficacy of SAAP-148 against various gram-positive and gram-negative bacteria was determined using PBS or 0.05% (wt/v) SPS immediately after 30 min incubation of the mixture. Additionally, ex vivo excision wound models were inoculated with 105 CFU MRSA for 1 h and exposed to SAAP-148, pexiganan, chlorhexidine or PBS for 1 h. Subsequently, samples were homogenized in PBS or 0.05% (wt/v) SPS and the number of viable bacteria was assessed. Results All tested antimicrobials displayed residual activity in tissue samples, resulting in a lower recovery of surviving bacteria on agar. SPS concentrations at ≥0.05% (wt/v) were able to neutralize the antimicrobial activity of SAAP-148, pexiganan and chlorhexidine, but not of SSD, Bactroban and Fucidin. Finally, SPS-neutralization in in vitro and ex vivo efficacy tests of SAAP-148, pexiganan and chlorhexidine against gram-positive and gram-negative bacteria resulted in significantly higher numbers of CFU compared to control samples without SPS-neutralization. Conclusions SPS was successfully used to neutralize residual activity of SAAP-148, pexiganan and chlorhexidine and this prevented an overestimation of their efficacy.

Background: Injectable radioactive iodine (I‐131) frequently is used to treat hyperthyroidism in cats. In human medicine, residual activity after injection of radionuclides has been reported, and the actual quantity administered is recorded after administration. Objective: Our aim was to evaluate actual administered dose variability after administration of preprepared I‐131 single unit doses for the treatment of hyperthyroidism in cats. Animals: Twenty‐seven cats with hyperthyroidism treated with I‐131 between April 2017 and March 2019. Methods: Retrospective observational study of cats treated with preprepared single unit I‐131 doses. For each dose, the measured activity before administration and residual activity were recorded. The measured dose and the actual dose administered were compared to the prescribed dose. Results: Measured activity before administration ranged from 88.4% to 103.3% of the prescribed dose. Mean residual activity was 5.2 ± 3.0 MBq (ranging from 1.5% to 15% of the prescribed dose). The actual dose administered (measured activity − residual activity) ranged from 79.1% to 100.2% of the prescribed dose. Seventeen of 28 (60.7%) of the actual administered doses differed between 10% and 20% of the prescribed dose. One administered dose had a >20% difference compared to the prescribed dose (79.10% of the prescribed dose). Conclusion and Clinical Importance: Our study identified variability in the residual and actual administered activity of I‐131 as compared to the prescribed dose, which should be taken into consideration when treating cats with (predrawn) I‐131. [ABSTRACT FROM AUTHOR]

Abstract Background Bio-efficacy and residual activity of SumiShield® 50WG (50%, w/w) with active ingredient clothianidin, a neonicotinoid compound, was assessed using an insecticide-susceptible laboratory strain of Anopheles arabiensis. Implications of the findings are examined in the context of potential alternative insecticides for indoor residual spraying in Lualaba Province, Democratic Republic of the Congo. Methods Contact surface bioassays were conducted for 48 weeks on four types of walls (unbaked clay, baked clay, cement, painted cement) in simulated semi-field experimental conditions using two different doses of clothianidin active ingredient (200 mg ai/sq m and 300 mg ai/sq m). Additionally, two types of walls (painted cement and baked clay) were examined in occupied houses using the 300-mg dosage. Laboratory-reared An. arabiensis were exposed to treated surfaces or untreated (controls) for 30 min. Mortality was recorded at 24-h intervals for 120 h. Results Under semi-field experimental conditions, there was no significant difference in mortality over time between the two doses of clothianidin. The mortality rates remained above 60% up to 48 weeks on all four wall surface types. The formulation performed better on cement and unbaked clay with a mean final mortality rate above 90%. Under natural conditions, there was no significant difference in response between baked clay and painted cement walls with a mean final mortality rate above 90%. The insecticide also performed significantly better in natural settings compared to semi-field experimental conditions. Conclusion Depending on the type of experimental surface, the residual activity of the two doses of clothianidin was between 28 and 48 weeks based on a 60% mortality endpoint. Clothianidin at 300 mg ai/sq m applied on two house walls (baked clay or painted cement) performed equally well (> 80% mortality) on both surfaces up to week 41 (approximately 9.5 months). Extended bioassay holding periods (up to 120 h) may present with excess natural mortality in the untreated controls, thus complicating analysis.

Eastern hemlock (Tsuga canadensis [L.] Carrière) is an important component of the riparian ecosystem. Due to the widespread establishment of hemlock woolly adelgid (Adelges tsugae Annand)(HWA) across the range of eastern hemlock, woodland trees may be infested for extended periods (years), resulting in their decline. Imidacloprid, a systemic neonicotinoid insecticide, may be used as a strategy in forested settings to manage HWA while more long-term solutions become established, such as biological controls. Symptoms of prolonged infestation include extensive dieback and thinned canopies. In this study, trees with a diameter at breast height (DBH) of 24.7 ± 2.7 SD cm in poor condition were treated with imidacloprid. Trees were treated once by trunk-injection (IMA-jet) or by soil drench in the Greenbrier area of the Great Smoky Mountains National Park, Gatlinburg, TN, USA. Changes in tree growth and HWA density were measured for 3 consecutive years. Imidaclopridtreated trees recovered, whereas the untreated trees declined. Imidacloprid treatments resulted in significantly higher 3-year mean percent growth (65.6% to 71.7% of tips) compared to the untreated controls (10.5% of tips). HWA density 3-year means in the imidacloprid-treated trees (0.10 to 1.09 per cm) likewise were statistically different to the untreated trees (2.72 per cm). The extended activity of imidacloprid-treated hemlock was attributed to storage in the symplast (xylem ray parenchyma) and to perennial needle retention. This study demonstrates that trunk-injection with IMA-jet is effective against HWA and comparable with soil drench to protect trees in the long term (≥ 4 years). [ABSTRACT FROM AUTHOR]

Abstract Background: Information on the carryover of herbicides applied to the destruction of cotton stalks, as well as the withdrawal period necessary to prevent the development and productivity of the crop in succession from being affected are limited in the literature. Objective: The objective was to identify the carryover effect promoted by herbicides used in the management of the destruction of cotton stalks and to estimate the host free period for sowing soybean in succession. Methods: Two individual experiments were conducted simultaneously, one for single application and the other for sequential application of herbicide treatments. The experiments were installed in a factorial scheme (15x5), in a randomized block design with four replications. The first factor evaluated was herbicide treatments and the second factor was five soybean sowing times after application (0, 30, 60, 90 and 120 days). The herbicides used in the treatments were 2,4-D, glyphosate, saflufenacil, [imazapic + imazapyr], dicamba, fluroxypyr and sulfentrazone. Results: As this work was conducted, the results provide a carryover indicator. It is concluded that the single application and the sequential application of the glyphosate + dicamba + saflufenacil treatment has great carryover potential for soybean crops, with the host free period for sowing the crop exceeding 120 days after application. Conclusions: The treatments 2,4-D, 2,4-D + glyphosate, glyphosate + saflufenacil + fluroxypyr had the lowest host free period intervals, even when in sequential application. The treatment with application of 2,4-D alone showed the lowest carryover potential for soybean.

The insecticidal efficacy and persistence of Nigerian raw diatomaceous earth (DE) were evaluated in the laboratory on cowpea against Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae). The raw DE was applied to 1.5 kg lots of cowpea seeds at 0 (untreated control), 250, 500, 750, 1000 and 1500 mg/kg, and a commercial DE formulation (Protect-It®) applied at 1000 mg/kg was included in the test as positive (treated) control. The treated cowpea seeds were kept under ambient laboratory conditions (26 - 34°C and 24 - 93% RH. Bioassays were conducted on samples taken from each treatment at the day of storage and every 30 d for 6 consecutive months. Adult C. maculatus were exposed for 3 and 5 d to the samples and adult mortality was assessed over this exposure interval and progeny production and seed damage were assessed after additional 30 d. On freshly treated cowpea, both the raw DE and Protect-It® were highly effective against C. maculatus causing 100% adult mortality following 5 d of exposure. In general, the raw DE was less persistent on cowpea providing complete adult mortality only for two months. Protect-It® on the other hand was stable over the 6- month period of storage causing 95.8 to 100% adult mortality. None of the treatments completely inhibited progeny production after 2-3-moths storage period. The results of this study indicated that Protect-It® may provide suitable protection for 6 months against C. maculatus, but the raw DE in its present state is not suitable for long-term protection against this insect pest.

Background & objectives: There is an urgent need of introducing new insecticide molecules with novel modes of action to counter the ever growing insecticide-resistance in mosquito vectors. In the present study, a new insecticide molecule, SumiShield 50 WG (clothianidin 50%, w/w) was investigated for its efficacy as an indoor residual spray along with its residual action in comparison to deltamethrin, pirimiphos-methyl and bendiocarb. Methods: The study area included three villages in Almatti Dam catchment area in Bagalkot district, Karnataka, India. Spraying was done using Hudson sprayers with the following dosages—Clothianidin, 300 mg AI/m2; deltamethrin, 25 mg AI/m2; bendiocarb, 400 mg AI/m2; and pirimiphos-methyl, 1 g AI/m2. Cone bioassays were conducted on cement and mud plastered surfaces at fortnightly intervals to assess the bioefficacy and residual activity. Mosquito densities in the sprayed houses were recorded at regular intervals for assessment of the insecticidal efficacy. Filter paper samples collected from the sprayed houses were analyzed for insecticide content sprayed on different wall surfaces at the Walloon Agricultural Research Institute, Gembloux, Belgium. Results: Chemical content analysis of filter paper samples revealed that the applied to target ratios were in the acceptable range (1 + 0.5) for all the treatment types. Duration of persistence of effectiveness of bendiocarb (≥80% mortality in cone bioassays) was 19 to 21 wk on cement plastered surfaces and 15 to 19 wk on mud plastered surfaces. Duration of persistence of effectiveness of deltamethrin was 17 to 21 wk on both mud and cement plastered surfaces and that of pirimiphos-methyl was 15 to 19 wk. For SumiShield, it was 17 to 25 wk on both types of surfaces, indicating slow action of SumiShield. The densities of Anopheles culicifacies were lower in bendiocarb sprayed houses throughout the observation period, followed by pirimiphos methyl, deltamethrin and clothianidin sprayed houses. In case of other mosquitoes also, similar trend was observed. Interpretation & conclusion: Considering the persistence of effectiveness of SumiShield on sprayed surfaces, effectiveness in reducing the density of mosquitoes, operational feasibility, safety and community acceptance, the formulation of clothianidin is a better option for IRS for the control of insecticide-resistant mosquito vectors.

Shielding of a neutron source housing for 1 Ci 241Am-Be source has been designed and fabricated based on the simulation carried out using Monte Carlo code FLUKA. Neutron and photon dose equivalent rates at the surface and at 1 m distance from the surface of the housing were calculated using FLUKA simulation and measured using gamma and neutron dose rate meters. The calculated and measured gamma and neutron dose equivalent rates agree well. Neutron spectra outside the source housing were generated using FLUKA simulation and measured with the ROSPEC + simple scintillation spectrometer neutron spectrometry system and also agree reasonably well. Gamma spectra outside the source housing and residual activity due to activation products in stainless steel and lead of the housing were also generated through simulation. [ABSTRACT FROM AUTHOR]

Information about the residual activity of herbicides sprayed in the control of cotton stalks and its potential to affect the development and productivity of corn sown in the following crop are limited. The objective of this work was to identify the carryover effect promoted by the single and sequential application of herbicides used in the control of cotton stalks and to estimate the plant-back for corn sowing. Two trials were carried out simultaneously in a greenhouse, one for a single application and one for a sequential application of herbicides treatments. It was used a 15 x 5 factorial scheme, in a randomized block design with four replicates. The first factor was composed of herbicide treatments and the second factor of five sowing seasons after the application (0, 30, 60, 90 and 120 days). The experimental plots were composed of plastic pots with a capacity of 3 dm3 filled with loamy soil (470 g kg-1 clay), dried and sieved. The herbicides sprayed were 2,4-D, glyphosate, saflufenacil, [imazapic + imazapyr], dicamba, fluroxypyr, and sulfentrazone. The sequential application of most treatments provided an increase in the residual activity of the evaluated herbicides. The 2,4-D (1,340 g ha-1), 2,4-D + glyphosate (1,340 + 720 g ha-1) and 2,4-D + glyphosate + saflufenacil (1,340 + 720 + 105 g ha-1) presented the shortest safety intervals and were those that presented the lowest risk of affecting the corn sown in succession, even in sequential applications. However, the treatments that consisted of association with herbicides with higher residual activity in the soil such as dicamba, fluroxypyr, sulfentrazone and [imazapic + imazapyr], presented higher carryover potential for corn crop, being observed a safety interval greater than 94 days after sequential application of 2,4-D + glyphosate + sulfentrazone. [ABSTRACT FROM AUTHOR]

Background: Accurate determination of the efficacy of antimicrobial agents requires neutralization of residual antimicrobial activity in the samples before microbiological assessment of the number of surviving bacteria. Sodium polyanethol sulfonate (SPS) is a known neutralizer for the antimicrobial activity of aminoglycosides and polymyxins. In this study, we evaluated the ability of SPS to neutralize residual antimicrobial activity of antimicrobial peptides [SAAP-148 and pexiganan; 1% (wt/v) in PBS], antibiotics [mupirocin (Bactroban) and fusidic acid (Fucidin) in ointments; 2% (wt/wt))] and disinfectants [2% (wt/wt) silver sulfadiazine cream (SSD) and 0.5% (v/v) chlorhexidine in 70% alcohol].Methods: Homogenates of human skin models that had been exposed to various antimicrobial agents for 1 h were pipetted on top of Methicillin-resistant Staphylococcus aureus (MRSA) on agar plates to determine whether the antimicrobial agents display residual activity. To determine the optimal concentration of SPS for neutralization, antimicrobial agents were mixed with PBS or increasing doses of SPS in PBS (0.05-1% wt/v) and then 105 colony forming units (CFU)/mL MRSA were added. After 30 min incubation, the number of viable bacteria was assessed. Next, the in vitro efficacy of SAAP-148 against various gram-positive and gram-negative bacteria was determined using PBS or 0.05% (wt/v) SPS immediately after 30 min incubation of the mixture. Additionally, ex vivo excision wound models were inoculated with 105 CFU MRSA for 1 h and exposed to SAAP-148, pexiganan, chlorhexidine or PBS for 1 h. Subsequently, samples were homogenized in PBS or 0.05% (wt/v) SPS and the number of viable bacteria was assessed.Results: All tested antimicrobials displayed residual activity in tissue samples, resulting in a lower recovery of surviving bacteria on agar. SPS concentrations at ≥0.05% (wt/v) were able to neutralize the antimicrobial activity of SAAP-148, pexiganan and chlorhexidine, but not of SSD, Bactroban and Fucidin. Finally, SPS-neutralization in in vitro and ex vivo efficacy tests of SAAP-148, pexiganan and chlorhexidine against gram-positive and gram-negative bacteria resulted in significantly higher numbers of CFU compared to control samples without SPS-neutralization.Conclusions: SPS was successfully used to neutralize residual activity of SAAP-148, pexiganan and chlorhexidine and this prevented an overestimation of their efficacy. [ABSTRACT FROM AUTHOR]

Phenylketonuria (PKU), caused by phenylalanine hydroxylase (PAH) gene variants, is a common autosomal inherited metabolic disease. So far, 1111 PAH variants have been revealed. The residual activity of the PAH variants is the key determinant of the metabolic phenotype and BH 4 responsiveness in PKU patients. In this study, the spectrum of PAH variants in 1083 Chinese PKU patients was analyzed. Then 20 variants (p.L52F, p.R86P, p.L128P, p.L142P, p.D163N, p.C203G, p.E214G, p.F260L, p.M276T, p.L311R, p.P314A, p.L364F, p.Q375H, p.F382I, p.A395S, p.V412D, p.E108*, p.C203*, p.C284* and p.E353*) were expressed in COS-7 cells. The residual activities and protein expression levels were detected by isotope-dilution liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) and Western blotting, respectively. We compared the results of the phenotypic prediction based on APV and PAH activity respectively, and further explored the relationship between residual activity and phenotype in PKU patients. We reported 9 newly discovered PAH variants for the first time, thereby expanding the spectrum of PAH variants. Among the 20 variants in our assay, 8 variants showed mild impaired residual activities (48–92%) and approximately normal protein expression levels compared to the wild-type PAH. In contrast, 9 variants showed severely impaired residual activities (0–34%) and reduced protein expression. However, three variants (p.L52F, p.F260L and p.P314A) showed impaired residual activities (5%, 32% and 29%), although the proteins were well expressed. We assigned APV scores for 14 variants, in which the results of the phenotypic prediction were consistent for 12/14 (86%) variants based on APV and residual activity respectively, and the residual activity correctly predicted 17/22 (77%) of the patients. Our study helped to further understand the genotype-phenotype correlation in PKU patients. • 20 variants of Phenylalanine Hydroxylase (PAH) gene impair enzyme activity in vitro. • Nine PAH gene variants were reported for the first time. • Allelic phenotype values (APV) scores were assigned for 14 PAH variants. • Phenotypic predictions were consistent for 86% variants based on APV and PAH activity. • PAH activity correctly predicted the phenotype in 77% of phenylketonuria patients. [ABSTRACT FROM AUTHOR]

Western flower thrips, Frankliniella occidentalis, is one of the most destructive insect pests of greenhouse-grown horticultural crops. The primary method of managing western flower thrips populations involves applications of insecticides; however, there is no information associated with the effect of the insect growth regulator, pyriproxyfen, or the entomopathogenic fungus, Isaria fumosorosea, on western flower thrips pupae in growing media. Therefore, four laboratory experiments were conducted to determine the effect of pyriproxyfen and I. fumosorosea applied as a drench to growing media on western flower thrips pupae. Expt. 1 evaluated the efficacy of pyriproxyfen and I. fumosorosea on western flower thrips pupae. Based on the results from Expt. 1, Expt. 2 assessed the effect of pyriproxyfen in two growing media (LC1 and BM1) on western flower thrips pupae. Expts. 3 and 4 determined the residual activity of pyriproxyfen in growing media on western flower thrips pupae 3, 5, 7, and 14 days after treatments were applied. The pyriproxyfen treatment resulted in a significantly lower estimated mean probability of western flower thrips adults captured on yellow sticky cards (17%) compared with the water control (59%), untreated check (88%), and two I. fumosorosea treatments (46% for 1.0 g and 41% for 2.0 g of Ancora) in Expt. 1. However, for the two growing media in Expt. 2, the estimated mean probability of western flower thrips adults captured on yellow sticky cards was not significantly different between the pyriproxyfen treatment (LC1 = 15%; BM1 = 12%) and the water control (LC1 = 41%; BM1 = 24%). For either the pyriproxyfen treatment or the untreated check, there was no evidence of a significant difference between the two growing media on the estimated mean probability of western flower thrips adults captured on yellow sticky cards. Furthermore, there was no evidence of any residual activity 3 days after drench applications of pyriproxyfen. The results of the study have demonstrated that drench applications of pyriproxyfen are not affecting survival of western flower thrips pupae. [ABSTRACT FROM AUTHOR]

ABSTRACT Herbicides aminocyclopyrachlor and indaziflam are under development in Brazil. Information about the behaviors in Brazilian soils and climate is scarce. Thus, the present work has aimed to evaluate the persistence of biological activity and leaching potential of aminocyclopyrachlor and indaziflam in contrasting textured soils by means of bioassays. For the evaluation of persistence, four experiments were performed, in which soils with different textures were studied in different time periods between herbicide application and bioindicator sowing (beet and soybeans). To determine leaching potential, three blades of rainfall (0, 30 and 60 mm) were simulated, each constituting a single experiment in soils with different textures and five bands of depth in the columns. The bioindicator used for the leaching tests was beet. The persistence of biological activity of aminocyclopyrachlor and indaziflam was greater than 150 days. In clayey soil there was less persistent aminocyclopyrachlor than in the loam texture. For indaziflam there was no difference in persistence between the two soils. Regarding the leaching potential, it was observed that the precipitations have the capacity to interfere with the leaching of herbicides aminocyclopyrachlor and indaziflam. Aminocyclopyrachlor has greater potential for leaching than indaziflam. The first one has its mobility increased when applied to soil of loam texture in relation to very clayey soil. As for indaziflam, marked differences between soils with different textures have not been noticed.

The effects of selected process conditions for the sol-gel encapsulation of laccase enzymatic extract, obtained from Coriolus hirsutus, were investigated. Screening trials were carried out to identify the parameters having the most pertinent effects on the encapsulation efficiency (EE) and the residual laccase activity. These parameters included water/silane molar ratio (r), HCl content and protein loading, for the pre-gel silica sol as well as the required time for gel drying and for aging, for the sol-gel process. The experimental findings indicated that a sol-gel drying time of over 6 h resulted in a complete loss of laccase catalytic activity, while an increase in the gel aging time led to an enhancement of the residual enzyme activity. Except for r, the investigated parameters demonstrated no significant effect on the EE of the sol-gel encapsulated enzymatic extract. Overall, the encapsulation of laccase extract in the sol-gel matrix resulted in an enhancement of its catalytic activity, where its highest residual activity (349%) was obtained with an r-value of 4, an HCl content of 4 µmol and a protein loading of 1 mg/mL, using 6 and 24 h of drying and aging times, respectively. [ABSTRACT FROM AUTHOR]

The heat treatment of oil palm fruit using saturated steam (413 K) in conventional oil palm processing has been reported to be ineffective in terms of heat distribution and penetration into the fruit bunch inner layer; hence, there is a desire to explore other alternative processes. In this study, oil palm fruit was treated in water at temperatures between 308 K and 343 K. The effects of the treatment on the in vivo activity of the lipase, the abscission layer of the fruit, and the integrity of the oil globule membrane were observed. The results showed in vivo residual lipase activity to be almost completely inactivated after 40 min of heat treatment at 343 K. The micrograph of the fruit mesocarp exhibited disintegration of the oil globule membrane as well as dissolution of the pectin layer architecture of the abscission zone after the treatment at this temperature. A dynamic mathematical modeling of heat transfer was employed, and coupled with reaction kinetics of lipase inactivation. The inactivation kinetics was found to be a non-elementary reaction, and the initial rate constant, k0dec, and activation energy, Edec, of the reaction were estimated to be 0.035 U−0.85/kg-mes−0.85⋅min and 153,052 kJ/kmol, respectively. The findings suggested the viability of water as a medium of heat treatment instead of the conventional steam treatment in oil palm processing.

Thiencarbazone-methyl is a new herbicide for the selective control of grasses and broadleaf weeds primarily in corn. The active ingredient belongs to the chemical class of sulfonly-amino-carbonyl-triazolinones (SACT) and acts as an inhibitor of the ALS-enzyme. The compound offers cross spectrum activity against grasses and broadleaf weeds and can be applied at the pre-emergence and the post-emergence timing. The use rate depends on the application timing and may vary from 22 – 45 g a.i./ha in pre-emergence applications and 10 – 15 g a.i./ha in post-emergence applications. Sequential treatments are possible as long as the maximum seasonal dose of 45 g a.i./ha is not exceeded. In commercial corn herbicides, TCM is always combined with safener technology such as the novel safener cyprosulfamide and with other herbicidal active ingredients. In pre-emergence applications, the primary herbicidal mixpartner is isoxaflutole. In herbicides designed for postemergence use, TCM is co-formulated with foramsulfuron, iodosulfuron or tembotrione. The commercial herbicides composed of TCM and CSA plus sulfonylurea or triketone partners have demonstrated high weed control success in conventional and herbicide-tolerant corn production systems. Depending on the product, the potential for one pass weed control has been confirmed. Control of perennial grasses like Sorghum halapense and Elymus repens together with control of problem weeds like Polygonum convolvulus and suppression of Cirsium arvense and Convolvulus arvensis appear to be among the most attractive features of TCM-based herbicides under European conditions. High crop tolerance of herbicides combining two or three highly active ingredients in one commercial product is ensured by the novel safener cyprosulfamide which can protect corn via root uptake and via leaf uptake from herbicide damage.

Terbuthylazine was used for weed control in German maize cropping in 2011 on nearly 86 % of total maize acreage. The ongoing success of this 45 year old herbicide can be explained by the various features for its use in maize as well as by responsible handling and care. Characteristic features of terbuthylazine are a broad controlled weed spectrum, superior residual activity, application timing flexibility from pre- to late postemergence, excellent crop tolerance, low soil mobility, perceivable speed of efficacy and suitability as partner for other active ingredients. Thanks to its combinability, terbuthylazine has maintained its importance in maize cropping, although the ubiquitous occurrence of triazine-resistant biotypes always has to be expected. In a weed monitoring in Germany and Austria in the 2008 and 2009 field season, the broad controlled weed spectrum and the efficacy of terbuthylazine in mixture with the 4-HPPD-inhibitor mesotrione on triazineresistant weed biotypes have been proven comparatively. 4-HPPD-inhibitors are preferred mixture partners due to their physiological synergism in combination with terbuthylazine. This feature enables a reduction of use rate of both terbuthylazine and mixture partner. Targeted post-emergence application of optimized pre-mixture herbicides achieves enhanced reliability and a noticeable increase of speed of efficacy. Combinations of terbuthylazine and residual graminicides offer the advantage of an all-embracing control of grass and broad leaved weed flora in maize by one pass only. Terbuthylazine is also effective against weeds not controlled adequately by other maize-selective herbicides. For reasons of preventative ground water protection, since 1991 a targeted management of the active ingredient terbuthylazine is carried out by manufacturers and registration holders. It envisages a limitation of terbuthylazine usage in maize only, one use per season in mixture with other active ingredients in spring only, and a maximum use rate of 750 g/ha. For treatments in areas with vulnerable groundwater situations (e. g. in open exposed Jurassic Karst formations) other herbicides than terbuthylazine containing products are strongly recommended. These measures have been demonstrated to be successful; in case of consequent compliance with these stewardship measures terbuthylazine can be continuously used as basic active ingredient in chemical weed control in maize for the future, maintaining all the advantages of this active substances for agriculture in Europe.

No Brasil, a maior parte dos cultivos de algodão encontra-se em regiões de cerrado dos Estados do Mato Grosso e Bahia, em áreas que naturalmente são constituídas de solos ácidos. Objetivou-se neste trabalho estudar a influência da acidez do solo sobre a persistência dos herbicidas trifloxysulfuron-sodium e pyrithiobac-sodium, utilizando um bioindicador como técnica de detecção. Foram conduzidos simultaneamente quatro experimentos: dois com o herbicida trifloxysulfuron-sodium (7,5 e 15 g ha-1) e dois com o pyrithiobac-sodium (70 e 140 g ha-1). Em todos os tratamentos foi utilizado delineamento experimental inteiramente casualizado, com quatro repetições, em esquema fatorial (3x8+3). Os fatores estudados foram três tipos de solo (com níveis de pH 4,2, 4,9 e 5,5) e oito épocas de semeadura da espécie bioindicadora (0, 30, 60, 90, 120, 150, 180 e 210 DAA), além de três testemunhas sem aplicação do herbicida. A persistência do trifloxysulfuron-sodium na dose de 7,5 g ha-1 não foi influenciada pelos valores de pH. No entanto, na dose de 15 g ha-1 a maior persistência da atividade biológica foi verificada no solo com maior pH. Quando o pyrithiobac-sodium foi aplicado no solo com menor pH, nas doses de 70 e 140 g ha-1, o tempo necessário foi maior para que ocorresse redução da persistência. Contudo, aos 210 DAA não foram observadas diferenças na persistência do pyrithiobac-sodium (70 g ha-1) entre diversos valores de pH. Todavia, na dose de 140 g ha-1 do pyrithiobac-sodium, o solo com maior pH apresentou a maior persistência desse herbicida.In Brazil, most of the areas planted with cotton are located in the cerrado regions of Mato Grosso and Bahia, in naturally acidic soil. The objective of this work was to study the influence of soil acidity on the persistence of trifloxysulfuron-sodium and pyrithiobac-sodium, using a bioindicator as detection technique. Four experiments were conducted simultaneously: two with trifloxysulfuron-sodium (7.5 and 15 g ha-1), and two with pyrithiobac-sodium (70 and 140 g ha-1), using a completely randomized design with four replications in a factorial scheme (3x8+3). Treatments were composed by three types of soil (at pH levels 4.2, 4.9 and 5.5), eight sowing dates for the bio-indicator (0, 30, 60, 90, 120, 150, 180, and 210 DAA), and three control treatments, without herbicide application. The persistence of trifloxysulfuron-sodium at doses of 7.5 g ha-1 was not influenced by the pH values. However, at a dose of 15 g ha-1 the highest increase in the persistence of biological activity was observed in soil with higher pH. When pyrithiobac-sodium was applied to the soil with lower pH, at doses of 70 and 140 g ha-1, a longer time period was needed for persistence to reduce. But at 210 DAS there were no differences in the persistence of pyrithiobac-sodium (70 g ha-1) between the different pH values. However, at the dose of 140 g ha-1 of pyrithiobac-sodium, the soil with the highest pH showed the highest persistence of this herbicide.

Com o objetivo de avaliar o efeito residual de flumioxazin sobre a emergência de plantas daninhas em solos de texturas distintas, foi realizado um experimento em casa de vegetação. Os tratamentos foram constituídos pela combinação de quatro épocas de aplicação: 14, 10, 7 e 0 dias antes da semeadura das espécies de plantas daninhas, com duas doses de flumioxazin (25 e 40 g ha-1) e uma testemunha sem aplicação para cada planta daninha em solos de texturas distintas. O efeito residual do herbicida flumioxazin foi avaliado por meio da contagem do número de plantas emersas de cada espécie aos 35 dias depois da semeadura (DDS). O controle do fluxo inicial de emergência de plantas daninhas variou em função do tipo de solo, do período de tempo entre a aplicação e a semeadura das espécies e também da dose. A. tenella, D. horizontalis, D. insularis, D. tortuosum, E. heterophylla, N. physaloides e S. latifolia foram as espécies mais sensíveis à aplicação de flumioxazin (25 e 40 g ha-1).This work aimed to evaluate the residual effect of flumioxazin on weed emergence in soils of distinct textures. Treatments were constituted by the combination of four periods of application (14, 10, 7 and 0 days before sowing) with two rates of flumioxazin (25 and 40 g ha-1), and no herbicide application for each weed species in soils with distinct textures. Residual activity of flumioxazin was evaluated by counting the emerged weeds for each species at 35 days after sowing. Control of initial flows of weed emergence varied with soil type, period of time between herbicide application and weed sowing. A. tenella, D. horizontalis, D. insularis, D. tortuosum, E. heterophylla, N. physaloides and S. latifolia, in both soils, were the most susceptible species to flumioxazin, applied at 25 and 40 g ha-1.

Developing Bacillus thuringiensis-based formulations is an old technology which has been revived during recent decades. The spore-crystal complex (being the main ingredient in these preparations) has been the main objective of this research, involving the search for new or improved strains. The type of materials used included a wide variety of completely biodegradable ingredients which could have been leaves, stems or fruit which when dried and ground could serve as feeding stimulants, as well as molasses and sugars. Sticky material such as gum providing adherence or starches working as encapsulating agents can both avoid dispersion by wind and wash-off by rain. Dyes and optical brighteners initially offer active protection against UV radiation and some other agents work as toxic activity enhancers. All of them are environmentally-friendly materials, completely harmless for human beings, other vertebrates, plants and even for beneficial insects so that the formulation is fully acceptable and ingested, thereby ensuring that it is highly effective. The foregoing has led to the manufacturing of a wide variety of commercial products whose effectiveness has positioned them in international markets; however, ongoing research provides specific solutions against new pests or is aimed at already-known ones avoiding resistance. Key words: Biological control; entomopathogen; toxic activity; feeding stimulants; residual activityEl desarrollo de las formulaciones insecticidas elaboradas a base de la bacteria Bacillus thuringiensis es una tecnología centenaria que ha recibido un fuerte impacto en décadas recientes. La mezcla de esporas y cristales, que es el principio activo de estas preparaciones, ha sido objeto de estudio constante y en ello se destaca la búsqueda de cepas cada vez más potentes o mejoradas. Así mismo, los materiales utilizados incluyen una amplia variedad de ingredientes completamente biodegradables como pueden ser partes de las plantas que el insecto consume, tales como hojas, tallos o frutos secos y molidos que pueden funcionar como estimulantes de la alimentación, además de melazas o azúcares. Algunas sustancias pegajosas como las gomas, que dan la capacidad de adherencia, o los almidones, que funcionan como agentes encapsulantes, sirven para evitar el arrastre por el viento y el lavado por la lluvia. Los colorantes y abrillantadores ópticos brindan al principio activo protección contra la luz UV, y otros agentes funcionan como potenciadores de la actividad tóxica. Todos ellos son amigables al ambiente y e inocuos para el hombre, otros vertebrados, plantas, e incluso para insectos benéficos, pero simultáneamente son capaces de ser ampliamente aceptados por los insectos plaga, con la intención de que la formulación sea ingerida y, finalmente, sea altamente efectiva. Esto ha traído como consecuencia la fabricación de una amplia variedad de productos comerciales cuya efectividad los ha posicionado en el mercado mundial, pero cuya investigación continúa para brindar formulaciones específicas hacia nuevas plagas o evitar la resistencia en aquellas ya conocidas. Palabras clave: control biológico; entomopatógeno; actividad tóxica; fagoestimulantes; actividad residual

Background: Indoor residual spraying with insecticide is recommended for malaria control in high-transmission settings. Determination of residual activity of insecticides is essential for the selection of appropriate indoor spraying policy. The present study was undertaken to evaluate the residual effect of bendiocarb, a carbamate insecticide used in Madagascar, on different indoor surfaces in order to elaborate future vector control interventions. Methods: The residual activity of bendiocarb was evaluated in both experimental huts and houses. Tests in experimental huts on different substrates represented a small scale-field trials. The houses IRS performed in parallel of experimental huts IRS, was done to compare semi-field results and field results. Bioassays according to the World Health Organization (WHO) standard protocol were carried out on different substrates impregnated with bendiocarb using susceptible strains of Anopheles arabiensis and Aedes albopictus. Results: Bendiocarb induced significantly high mortality in treated huts against exposed mosquito (p < 0.005) compared to untreated huts. The mortality is up to the WHO threshold of 80 % during 5 months post-treatment. Using a multivariate analysis, Ae. albopictus mortality decreased significantly from the 3rd month post-treatment. However, An. arabiensis mortality decreased significantly from the 4th month after treatment. Comparing mosquito mortality results from the mud experimental huts and the mud houses showed no significant difference regarding the persistence of bendiocarb on wall. Conclusions: Current data suggest variable persistence of bendiocarb according to the type of wall surfaces, highlighting the importance of testing insecticide for IRS in local context before using them in large scale. Data from this study validate also the importance of using experimental huts as representative tool to evaluate the effectiveness of an insecticide. [ABSTRACT FROM AUTHOR]