Wireworms, the larvae of click beetles (Coleoptera: Elateridae), have had a centuries-long role as major soil insect pests worldwide. With insecticidal control options dwindling, research on click ...beetle biology and ecology is of increasing importance in the development of new control tactics. Methodological improvements have deepened our understanding of how larvae and adults spatially and temporarily utilize agricultural habitats and interact with their environment. This progress, however, rests with a few pest species, and efforts to obtain comparable knowledge on other economically important elaterids are crucial. There are still considerable gaps in our understanding of female and larval ecology; movement of elaterids within landscapes; and the impact of natural enemies, cultivation practices, and environmental change on elaterid population dynamics. This knowledge will allow generation of multifaceted control strategies, including cultural, physical, and chemical measures, tailored toward species complexes and crops across a range of appropriate spatial scales.
KEY MESSAGE: Consolidates relevant molecular and phenotypic information on cassava to demonstrate relevance of heterosis, and alternatives to exploit it by integrating different tools. Ideas are ...useful to other asexually reproduced crops. Asexually propagated crops offer the advantage that all genetic effects can be exploited in farmers’ production fields. However, non-additive effects complicate selection because, while influencing the performance of the materials under evaluation, they cannot be transmitted efficiently to the following cycle of selection. Cassava can be used as a model crop for asexually propagated crops because of its diploid nature and the absence of (known) incompatibility effects. New technologies such as genomic selection (GS), use of inbred progenitors based on doubled haploids and induction of flowering can be employed for accelerating genetic gains in cassava. Available information suggests that heterosis, non-additive genetic effects and within-family variation are relatively large for complex traits such as fresh root yield, moderate for dry matter or starch content in the roots, and low for defensive traits (pest and disease resistance) and plant architecture. The present article considers the potential impact of different technologies for maximizing gains for key traits in cassava, and highlights the advantages of integrating them. Exploiting heterosis would be optimized through the implementation of reciprocal recurrent selection. The advantages of using inbred progenitors would allow shifting the current cassava phenotypic recurrent selection method into line improvement, which in turn would allow designing outstanding hybrids rather than finding them by trial and error.
Summary Background Daily inhaled corticosteroids are an effective treatment for mild persistent asthma, but some children have exacerbations even with good day-to-day control, and many discontinue ...treatment after becoming asymptomatic. We assessed the effectiveness of an inhaled corticosteroid (beclomethasone dipropionate) used as rescue treatment. Methods In this 44-week, randomised, double-blind, placebo-controlled trial we enrolled children and adolescents with mild persistent asthma aged 5–18 years from five clinical centres in the USA. A computer-generated randomisation sequence, stratified by clinical centre and age group, was used to randomly assign participants to one of four treatment groups: twice daily beclomethasone with beclomethasone plus albuterol as rescue (combined group); twice daily beclomethasone with placebo plus albuterol as rescue (daily beclomethasone group); twice daily placebo with beclomethasone plus albuterol as rescue (rescue beclomethasone group); and twice daily placebo with placebo plus albuterol as rescue (placebo group). Twice daily beclomethasone treatment was one puff of beclomethasone (40 μg per puff) or placebo given in the morning and evening. Rescue beclomethasone treatment was two puffs of beclomethasone or placebo for each two puffs of albuterol (180 μg) needed for symptom relief. The primary outcome was time to first exacerbation that required oral corticosteroids. A secondary outcome measured linear growth. Analysis was by intention to treat. This study is registered with clinicaltrials.gov , number NCT00394329. Results 843 children and adolescents were enrolled into this trial, of whom 288 were assigned to one of four treatment groups; combined (n=71), daily beclomethasone (n=72), rescue beclomethasone (n=71), and placebo (n=74)—555 individuals were excluded during the run-in, according to predefined criteria. Compared with the placebo group (49%, 95% CI 37–61), the frequency of exacerbations was lower in the daily (28%, 18–40, p=0·03), combined (31%, 21–43, p=0·07), and rescue (35%, 24–47, p=0·07) groups. Frequency of treatment failure was 23% (95% CI 14–43) in the placebo group, compared with 5·6% (1·6–14) in the combined (p=0·012), 2·8% (0–10) in the daily (p=0·009), and 8·5% (2–15) in the rescue (p=0·024) groups. Compared with the placebo group, linear growth was 1·1 cm (SD 0·3) less in the combined and daily arms (p<0·0001), but not the rescue group (p=0·26). Only two individuals had severe adverse events; one in the daily beclomethasone group had viral meningitis and one in the combined group had bronchitis. Interpretation Children with mild persistent asthma should not be treated with rescue albuterol alone and the most effective treatment to prevent exacerbations is daily inhaled corticosteroids. Inhaled corticosteroids as rescue medication with albuterol might be an effective step-down strategy for children with well controlled, mild asthma because it is more effective at reducing exacerbations than is use of rescue albuterol alone. Use of daily inhaled corticosteroid treatment and related side-effects such as growth impairment can therefore be avoided. Funding National Heart, Lung and Blood Institute.
Abstract Populations of various economic species of wireworms are increasing in the key cereal crop production areas of Canada and the United States. To address this problem, seed treatments are ...under development that both provide crop protection and significantly reduce populations equivalent in effectiveness to the formerly used but now deregistered organochlorine lindane. Herein, we evaluated isocycloseram (PLINAZOLIN technology), the first isoxazoline (GABA-gated Chloride Channel Allosteric Modulator) agricultural insecticide, as a seed treatment for the protection of cereal crops from the sugarbeet wireworm, Limonius californicus (Mannerheim). In wheat and barley field trials conducted over 4 years under extreme wireworm pressure, isocycloseram applied as a seed treatment at 5.0–7.5 g AI/100 kg seed was as effective as or more effective than the current industry standard thiamethoxam at 20.0 g AI/100 kg seed in protecting crop stand and yield. Isocycloseram also reduced neonate wireworms (produced from eggs during the growing season) and resident wireworms (in the field at the time of planting) to levels expected from the formerly used seed treatment lindane.
Wireworms are primary pests of potatoes in Canada. Presently, the highly toxic organophosphate phorate (i.e., Thimet 20G) is the only effective insecticide in use in Canada. As such, there is an ...urgent need for novel alternative treatments that provide competitive tuber blemish protection and wireworm reduction with a safer human and environmental portfolio. Herein we evaluated broflanilide, a novel meta-diamide insecticide for both tuber protection and wireworm mortality. When evaluated in field trials in Agassiz, British Columbia over 6 yr, broflanilide applied as a seed piece treatment (SPT) to mother tubers at 1.5–2.0 g AI/100 kg seed (approx. 50 g AI/ha), or as an in-furrow spray (IFS) at 0.23–0.25 g AI/100 m row (approx. 25 g AI/ha) was as effective at reducing blemishes to daughter tubers by wireworms (Agriotes obscurus) as phorate (Thimet 20G at 3230 g AI/ha), bifenthrin (Capture 2EC IFS at 300 g AI/ha) and clothianidin (Titan ST at 312.5 g AI/ha). In addition, broflanilide SPT and IFS applied at the above rates reduced resident wireworms (in the field at the time of planting) by 95.4–99.0% and neonate wireworms (produced from eggs laid during the growing season) by 98.1–100%. Similar results were obtained when broflanilide IFS (nonsystemic) was paired with clothianidin SPT (systemic) for broad-spectrum potato insect pest control. Strategies for the use of broflanilide on wheat (e.g., Teraxxa F4) in rotation with potatoes (Cimegra), both registered in Canada in 2020 are discussed.
Several Agriotes click beetle species are important pests of vegetables and field crops. Monitoring for beetles is generally done with pheromone-baited traps maintained in permanent locations. Since ...dispersal is mostly by walking, such traps may deplete populations around them, leading to underestimations of populations relative to nontrapped areas, and of concomitant risk of wireworm damage to nearby crops. We placed sets of five pitfall traps in field headland areas in 2015–2017, of which two were baited with Agriotes obscurus (L) or Agriotes lineatus (L) (Coleoptera: Elateridae) pheromone. Of these, one was maintained in a permanent location, while the other moved among the remaining positions. Traps were checked weekly over the emergence period. For A. obscurus, fixed and moving traps initially collected similar numbers, but the latter collected significantly more later in the season, indicating depletion around fixed traps. Depletion was most pronounced after a period of cold weather, and around the peak swarming period. Depletion observed for A. lineatus was not statistically significant.This indicates pheromone-baited traps used for walking insects can underestimate populations, but depletion rates vary with species and temperature and should be accounted for when traps are used to develop action thresholds or time control strategies.
Daily inhaled glucocorticoids are recommended for young children at risk for asthma exacerbations, as indicated by a positive value on the modified asthma predictive index (API) and an exacerbation ...in the preceding year, but concern remains about daily adherence and effects on growth. We compared daily therapy with intermittent therapy.
We studied 278 children between the ages of 12 and 53 months who had positive values on the modified API, recurrent wheezing episodes, and at least one exacerbation in the previous year but a low degree of impairment. Children were randomly assigned to receive a budesonide inhalation suspension for 1 year as either an intermittent high-dose regimen (1 mg twice daily for 7 days, starting early during a predefined respiratory tract illness) or a daily low-dose regimen (0.5 mg nightly) with corresponding placebos. The primary outcome was the frequency of exacerbations requiring oral glucocorticoid therapy.
The daily regimen of budesonide did not differ significantly from the intermittent regimen with respect to the frequency of exacerbations, with a rate per patient-year for the daily regimen of 0.97 (95% confidence interval CI, 0.76 to 1.22) versus a rate of 0.95 (95% CI, 0.75 to 1.20) for the intermittent regimen (relative rate in the intermittent-regimen group, 0.99; 95% CI, 0.71 to 1.35; P=0.60). There were also no significant between-group differences in several other measures of asthma severity, including the time to the first exacerbation, or adverse events. The mean exposure to budesonide was 104 mg less with the intermittent regimen than with the daily regimen.
A daily low-dose regimen of budesonide was not superior to an intermittent high-dose regimen in reducing asthma exacerbations. Daily administration led to greater exposure to the drug at 1 year. (Funded by the National Heart, Lung, and Blood Institute and others; MIST ClinicalTrials.gov number, NCT00675584.).
We evaluated the relative efficacy of six pheromone-baited traps used in trapping Agriotes obscurus (L.) click beetles (Coleoptera: Elateridae): original Yatlor Traps, Yatlor Funnel Traps, Vernon ...Beetle Traps, Unitraps, Baited Pitfall Traps, and Vernon Pitfall Traps. Traps were rated according to quantitative and qualitative criteria of importance for each of four trap uses: general surveys, scientific studies, IPM monitoring, and mass trapping. Measurable quantitative categories included: total catch of A. obscurus; time for assembly, installation, and inspection; exclusion of nontarget invertebrates; and cost. Qualitative criteria were small mammal exclusion, flooding, design and handling variability, and convenience for various field uses. The most desirable characteristics were determined for the above four uses, and the cumulative ranking based on quantitative criteria and all four uses was Vernon Pitfall Trap, Baited Pitfall Trap, Original Yatlor Trap, Vernon Beetle Trap, Yatlor Funnel Trap, and Unitrap.
A study was conducted to determine rates of recapture of marked
Agriotes obscurus
(AO) males released in a grassy field on four occasions in the centre of pheromone trap squares with traps spaced ...2.5, 5.0, 7.5 and 10.0 m apart. Concurrent catches of naturally occurring and naturally dispersed (wild) AO were also recorded. Catch of marked AO was highest during peak emergence when maximum weekly temperatures ranged from 15.7 to 17 °C, and rainfall was light. Mean catch in the 2.5–10.0 m trap squares was, respectively, 82.0, 79.0, 77.0 and 65.0%, which occurred within one week of release. Catch of marked AO were lower (range in 2.5–10.0 m squares: 74.5–50.5%) when released early in the activity period, due to lower temperatures and higher rainfall, and catch was protracted over 3 weeks. Catch during two releases under favourable weather late in the activity period was also reduced (range: 25–58%), likely due to loss of AO vigour and/or pheromone trap efficacy. Catch of wild AO was highest in traps spaced 7.5 or 10.0 m apart, suggesting independence of these traps, and between-trap competition at 2.5 and 5.0 m spacings. From these data, we estimated that an effective spacing for traps in mass trapping arrays would be approximately 6 m. Significantly higher catch of marked or wild AO occurred in traps that were upwind in all trap squares, indicating wind direction should be considered in structuring the placement of trap arrays in mass trapping programs in non-farmed headland areas.
Background More evidence is needed on which to base recommendations for treatment of mild-moderate persistent asthma in school-aged children. Objective The Pediatric Asthma Controller Trial (PACT) ...compared the effectiveness of 3 regimens in achieving asthma control. Methods A total of 285 children (ages 6-14 years) with mild-moderate persistent asthma on the basis of symptoms, and with FEV1 ≥ 80% predicted and methacholine FEV1 PC20 ≤ 12.5 mg/mL, were randomized to 1 of 3 double-blind 48-week treatments: fluticasone 100 μg twice daily (fluticasone monotherapy), fluticasone 100 μg/salmeterol 50 μg in the morning and salmeterol 50 μg in the evening (PACT combination), and montelukast 5 mg in the evening. Outcomes included asthma control days (primary outcome), exacerbations, humanistic measurements, and pulmonary function measurements. Results Fluticasone monotherapy and PACT combination were comparable in many patient-measured outcomes, including percent of asthma control days, but fluticasone monotherapy was superior for clinic-measured FEV1 /forced vital capacity ( P = .015), maximum bronchodilator response ( P = .009), exhaled nitric oxide ( P < .001), and PC20 ( P < .001). Fluticasone monotherapy was superior to montelukast for asthma control days (64.2% vs 52.5%; P = .004) and for all other control outcomes. Growth over 48 weeks was not statistically different (fluticasone, 5.3 cm; PACT combination, 5.3 cm; montelukast, 5.7 cm). Conclusion Both fluticasone monotherapy and PACT combination achieved greater improvements in asthma control days than montelukast. However, fluticasone monotherapy was superior to PACT combination in achieving other dimensions of asthma control. Growth was similar in all groups. Clinical implications Therefore, of the regimens tested, the PACT study findings favor fluticasone monotherapy in treating children with mild-moderate persistent asthma with FEV1 ≥ 80% predicted, confirming current guideline recommendations.
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