Spirotetramat resistance in Myzus persicae (Sulzer) (Hemiptera: Aphididae) and its association with the presence of the A2666V mutation.

BACKGROUND: Chemicals are widely used to protect field crops against aphid pests and aphid-borne viral diseases. One such species is Myzus persicae (Sulzer), a global pest that attacks a broad array of agricultural crops and transmits many economically damaging plant viruses. This species has evolved resistance to a large number of insecticide compounds as a result of widespread and repeated chemical use in many parts of the world. In this study, we investigated the evolution of resistance to a new plant protection product, spirotetramat, following reported chemical control failures. RESULTS: Our study provides clear phenotypic and genotypic evidence of spirotetramat resistance in populations of M. persicae from Australia. We show there is cross-resistance to other insecticides within the same chemical group, namely spiromesifen and spirodiclofen. We also demonstrate that resistance is associated with the previously reported mutation, A2226V in the target site of spirotetramat, acetyl-CoA carboxylase. Our genetic analysis found all resistant M. persicae populations belong to the same multi-locus clonal type and carry the A2226V mutation, which appears to be inherited as a dominant trait in this species. CONCLUSION: Our findings provide new insight into the resistance conferred by A2226V and have implications for the control of M. persicae in Australia and worldwide. A diagnostic assay developed in this study should serve as a valuable tool for future resistance monitoring and to support the implementation of pest management strategies. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Learnings from over a decade of increasing pesticide resistance in the redlegged earth mite, Halotydeus destructor (Tucker).

BACKGROUND: The redlegged earth mite, Halotydeus destructor (Tucker), is a destructive and economically important pest of winter grain crops and pastures in Australia. It is largely controlled by pesticides, but this mite has evolved resistance to pyrethroid and organophosphate chemicals. A national Resistance Management Strategy has been developed for pro-active management to delay further resistance evolution, though its success is reliant on a detailed understanding of the incidence, patterns of spread, current distribution and the nature of resistance in the field. Here, we report on a long-term resistance surveillance programme undertaken between 2006 and 2019 informed by resistance risk forecasting. RESULTS: By mapping the Australian distribution of resistance through time, we show that resistance is present across three Australian states and covers more than 3000 km. This current range includes a recently identified population exhibiting organophosphate resistance representing the most easterly location of resistance in H. destructor. Using field history information, we identify associations for the first time between crop management practices employed by farmers and the presence of pyrethroid resistance. Management strategies that could minimize the risk of further resistance include limiting local spread of resistance through farm hygiene practices, crop rotations and reducing pesticide usage. CONCLUSION: This study highlights the challenges of resistance in H. destructor but also indicates how quantitative resistance risk analysis can be developed to target field surveillance and delay further resistance. The management strategies highlighted in this study can help maintain the effectiveness of control options but will depend on farmer engagement and adoption. © 2021 Society of Chemical Industry.

Insecticide Responses in the Collembola Pest, Sminthurus viridis (Collembola: Sminthuridae), in Australia.

Lucerne flea (Sminthurus viridis Linnaeus) is an important establishment pest of winter grain crops and pastures in Australia. Control of S. viridis largely relies on the application of insecticides through foliar sprays or seed treatments; however, in recent years, farmers have faced increasing difficulties managing this pest. This is likely due to their high inherent tolerance to certain chemicals, although there are increasing concerns around emerging resistance. Despite this, there have been no studies worldwide investigating insecticide sensitivity shifts on S. viridis. Further, there is currently no established method to test the response of S. viridis to neonicotinoids, which are now widely used to protect many crops attacked by this species. Here, we established a robust and sensitive bioassay methodology to test neonicotinoids against S. viridis. We also generated important sensitivity data for the first time across multiple S. viridis populations from geographically distinct regions in Australia to two commonly used insecticides, omethoate, and imidacloprid. While there was variation in responses between populations for both chemicals, there is no evidence to suggest insecticide resistance has evolved in the field. This study is an important step for future monitoring of insecticide resistance in S. viridis, particularly given the considerable selection pressure imposed on this pest in Australia and its purported high-risk of evolving resistance.

Challenges in devising economic spray thresholds for a major pest of Australian canola, the redlegged earth mite (Halotydeus destructor).

BACKGROUND: A key component for spray decision-making in IPM programmes is the establishment of economic injury levels (EILs) and economic thresholds (ETs). We aimed to establish an EIL for the redlegged earth mite (Halotydeus destructor Tucker) on canola. RESULTS: Complex interactions between mite numbers, feeding damage and plant recovery were found, highlighting the challenges in linking H. destructor numbers to yield. A guide of 10 mites plant(-1) was established at the first-true-leaf stage; however, simple relationships were not evident at other crop development stages, making it difficult to establish reliable EILs based on mite number. Yield was, however, strongly associated with plant damage and plant densities, reflecting the impact of mite feeding damage and indicating a plant-based alternative for establishing thresholds for H. destructor. Drawing on data from multiple field trials, we show that plant densities below 30-40 plants m(-2) could be used as a proxy for mite damage when reliable estimates of mite densities are not possible. CONCLUSION: This plant-based threshold provides a practical tool that avoids the difficulties of accurately estimating mite densities. The approach may be applicable to other situations where production conditions are unpredictable and interactions between pests and plant hosts are complex.

Estimating Densities of the Pest Halotydeus destructor (Acari: Penthaleidae) in Canola.

Development of sampling techniques to effectively estimate invertebrate densities in the field is essential for effective implementation of pest control programs, particularly when making informed spray decisions around economic thresholds. In this article, we investigated the influence of several factors to devise a sampling strategy to estimate Halotydeus destructor Tucker densities in a canola paddock. Direct visual counts were found to be the most suitable approach for estimating mite numbers, with higher densities detected than the vacuum sampling method. Visual assessments were impacted by the operator, sampling date, and time of day. However, with the exception of operator (more experienced operator detected higher numbers of mites), no obvious trends were detected. No patterns were found between H. destructor numbers and ambient temperature, relative humidity, wind speed, cloud cover, or soil surface conditions, indicating that these factors may not be of high importance when sampling mites during autumn and winter months. We show further support for an aggregated distribution of H. destructor within paddocks, indicating that a stratified random sampling program is likely to be most appropriate. Together, these findings provide important guidelines for Australian growers around the ability to effectively and accurately estimate H. destructor densities.

Impact of Halotydeus destructor on crop seedlings at different plant developmental stages and levels of moisture stress.

Tolerance and compensatory ability after invertebrate damage are important components of plant defense and are affected by various endogenous and exogenous factors. Here, we examine the impact of feeding damage caused by different densities of the redlegged earth mite (Halotydeus destructor Tucker) on the performance and recovery of canola and wheat seedlings at different plant developmental stages, and when grown under three levels of moisture stress. Both canola and wheat were susceptible to feeding damage caused by H. destructor at early growth development stages (canola-cotyledon, first and second true leaf stage; wheat-GS10 and GS12), but tolerated damage at the later growth stages (canola-third true leaf stage; wheat-GS14). Wheat plants compensated completely for mite feeding damage, while canola plants showed partial compensation when feeding occurred at the cotyledon and first true leaf stages. Canola was susceptible to immediate feeding damage from H. destructor under all levels of moisture stress and did not compensate for this damage over time when grown in the unstressed and moderately stressed treatments. Under severe moisture stress conditions, plant performance traits and mite density often showed a nonlinear relationship, with growth initially increasing as mite density increased, but then decreasing markedly as densities exceeded 30 mites/100 cm(2). Wheat seedlings were susceptible to immediate feeding damage when grown in the unstressed and severe stress conditions, but were generally able to compensate for this damage regardless of moisture conditions. The implications of these results for the management of H. destructor are discussed.

Meat intake in Britain in relation to other dietary components and to demographic and risk factor variables: analyses based on the National Diet and Nutrition Survey of 2000/2001.

BACKGROUND: Red and processed meat intakes have been positively associated with the risk of several major chronic diseases. Understanding population intakes is important when formulating dietary recommendations. The present study investigated the dispersion of intakes of red and processed meat and associations with dietary, socio-demographic and risk factors. METHODS: The present study comprised a secondary analysis of the British National Diet and Nutrition Survey 2000/1, including 7-day dietary records, from 766 male and 958 female respondents aged 19-64 years. Composite dishes were disaggregated into primary ingredients. Self-reported vegetarians (V) were grouped into one stratum and other respondents were stratified into five groups (F1-F5) according to energy-adjusted red plus processed meat (RPM) intake, to give six strata. 7-day RPM intakes were adjusted to estimate 'usual' habitual intakes, using ratios of between-person to total variance in daily intakes. RESULTS: Mean recorded intakes of red, processed, white and total meat were 48, 41, 40 and 129 g day(-1) , respectively, in males and 30, 22, 30 and 82 g day(-1) in females. Estimated habitual intakes of RPM standardised to sex-specific energy intakes across the six strata were: 12 (V), 56, 76, 90, 105 and 137 g day(-1) in males and 5 (V), 34, 46, 55, 65 and 88 g day(-1) in females. Lower RPM consumers tended to be of higher social class and educational level and to have more favourable levels of some risk factors. CONCLUSIONS: Mean intakes of red, processed and white meat were of similar magnitude. Habitual intakes of RPM showed wide dispersion with one-quarter of males < 55 g day(-1) and one-quarter of females < 27 g day(-1) . Lowering overall RPM consumption could be achieved by seeking greater reductions among current high consumers.

Blood leak alarm interference by hydoxocobalamin is hemodialysis machine dependent.

CONTEXT: Hydroxocobalamin has been reported to interfere with the blood leak alarm on hemodialysis machines making it difficult to use this treatment modality after hydroxocobalamin infusion. OBJECTIVE: The objective was to determine if this interference with hydroxocobalamin occurs across hemodialysis machines by different manufacturers. Additionally, we aimed to see if this represented a colorimetric interference alone or if it is the optical properties of hydroxocobalamin. MATERIALS AND METHODS: Hydroxocobalamin was reconstituted per package insert. Food coloring was added to 0.9% saline to create the colors of the visual spectrum. Optical properties of absorbance and transmittance were measured. Hydroxocobalamin and the saline solutions were infused into the Fresenius 2008K™ and the Gambro Phoenix X36™ machines. Times were recorded from the start of the machine until the solution finished or the alarm triggered. RESULTS: When evaluating the Gambro Phoenix X36™ machine and dialysis circuit; the alarm did not trigger. In contrast, the blood leak alarm on the Fresenius 2008K™ machine was tripped by both the red solution and hydoxocobalamin infused per the package insert. The alarm stopped the machine between 128 and 132 seconds for the red solution and between 30 and 35 seconds with the hydroxocobalamin. Membranes of the circuits where the alarm tripped were examined and remained intact without blood. Results were validated on different machines with new circuits. DISCUSSION: Hydroxocobalamin infusion per package insert and the red saline solution prepared with Red Dye 40 both triggered the blood leak alarm and stopped the Fresenius 2008K™ machine. However, this was not true for the Gambro Phoenix X36™ machine as the alarm never triggered. The interference with the Fresenius 2008K™ appears colorimetric due to normal saline with Red Dye 40 triggering the alarm. CONCLUSION: We alert physicians to become familiar with the properties of individual dialysis machines prior to use of hydroxocobalamin. When facing difficulties with hemodialysis after the administration of hydroxocobalamin, consider attempting with a different manufactures machine or model if available or contact the manufacturer directly.

Developing a methodology for assigning glycaemic index values to foods consumed across Europe.

There is growing evidence that the glycaemic index (GI) of the diet is important with respect to body weight and metabolic disease risk. However, research is limited by the paucity of GI values for commonly consumed carbohydrate-rich foods in European countries. A new methodology has been developed for consistent assignment of GI values to foods across five European databases used in the Diogenes intervention study. GI values were assigned according to five decreasing levels of confidence (1) Measured values for specific foods; (2) Published values from published sources; (3) Equivalent values where published values for similar foods existed; (4) Estimated values assigned as one of three values representing low/medium/high GI ranges and (5) Nominal values assigned as 70, where no other value could be assigned with sufficient confidence. GI values were assigned to 5105 foods. In food records collected at baseline, the contribution to carbohydrate intake of foods assigned levels 1-2 ranged from 16% to 43% depending on country, and this increased to 53-81% including level 3 foods. The degree of confidence to assigned GI values differed across Europe. This standardized approach of assigning GI values will be made available to other researchers to facilitate further investigation into the effects of dietary GI on health.

Survival and reproduction of the pest mites Balaustium medicagoense and Bryobia spp. on winter grain crops.

Balaustium medicagoense and Bryobia spp. have recently been identified as emerging pests of winter crops and pastures in Australia. These mites have a high natural tolerance to currently registered pesticides, highlighting the need to develop alternative control strategies such as cultural controls which require an understanding of plant associations. In shade-house experiments, Bryobia spp. survived and reproduced successfully on pasture, lupins and oats, but progeny failed to reach the adult stage on canola and wheat. Balaustium medicagoense progeny failed to produce a generation on any crop but parental adults survived a few months on all crops, particularly wheat. Bryobia spp. damaged canola, pasture and lupins, but caused minimal damage to oats and wheat, whereas Ba. medicagoense caused considerable damage to wheat and lupins, but only moderate damage to canola, oats and pasture. Field survey data, taken from approximately 450 sites across southern Australia, combined with analysis of historical pest reports, suggest broadleaf crops such as canola, lucerne, lupins and weeds appear particularly susceptible to attack by Bryobia species. Balaustium medicagoense was more commonly found on cereals and grasses, although they also attacked broadleaf crops, particularly canola, lucerne and lupins. These findings show that the mites have the potential to be an important pest on several winter grain crops and pasture, but there are important differences that can assist in management strategies such as targeted crop rotations.

Determination of the glycaemic index of various staple carbohydrate-rich foods in the UK diet.

OBJECTIVE: To determine the glycaemic index (GI) of various staple carbohydrate-rich foods in the UK diet, and to consider the factors influencing the GI of foods. DESIGN: Subjects were served with 25 or 50 g portions of glucose on three occasions, followed by a selection of test foods providing an equal amount of available carbohydrate, in random order. Each test food was consumed by 10 subjects. Capillary blood glucose levels were measured in the fasted state and over the 120 min following commencement of consumption of the foods. SETTING: The study was carried out in a research institute (MRC Human Nutrition Research, Cambridge, UK). SUBJECTS: Forty-two healthy adult volunteers were studied. METHODS: The GI values of 33 foods were measured according to the WHO/FAO recommended methodology. These foods included various breads, breakfast cereals, pasta, rice and potatoes, all of which were commercially available in the UK. CONCLUSIONS: The results illustrate a number of factors which are important in influencing the GI of a food, highlighting the importance of measuring the GI of a food, rather than assuming a previously published value for a similar food. This is useful both to researchers analysing dietary surveys or planning intervention studies, and also to health professionals advising individuals on their diets.

No effect of a diet with a reduced glycaemic index on satiety, energy intake and body weight in overweight and obese women.

OBJECTIVE: To investigate whether a diet with a reduced glycaemic index (GI) has effects on appetite, energy intake, body weight and composition in overweight and obese female subjects. DESIGN: Randomized crossover intervention study including two consecutive 12-week periods. Lower or higher GI versions of key carbohydrate-rich foods (breads, breakfast cereals, rice and pasta/potatoes) were provided to subjects to be incorporated into habitual diets in ad libitum quantities. Foods intended as equivalents to each other were balanced in macronutrient composition, fibre content and energy density. SUBJECTS: Nineteen overweight and obese women, weight-stable, with moderate hyperinsulinaemia (age: 34-65 years, body mass index: 25-47 kg m(-2), fasting insulin: 49-156 pmol l(-1)). MEASUREMENTS: Dietary intake, body weight and composition after each 12-week intervention. Subjectively rated appetite and short-term ad libitum energy intake at a snack and lunch meal following fixed lower and higher GI test breakfasts (GI 52 vs 64) in a laboratory setting. RESULTS: Free-living diets differed in GI by 8.4 units (55.5 vs 63.9), with key foods providing 48% of carbohydrate intake during both periods. There were no differences in energy intake, body weight or body composition between treatments. On laboratory investigation days, there were no differences in subjective ratings of hunger or fullness, or in energy intake at the snack or lunch meal. CONCLUSION: This study provides no evidence to support an effect of a reduced GI diet on satiety, energy intake or body weight in overweight/obese women. Claims that the GI of the diet per se may have specific effects on body weight may therefore be misleading.

In vitro effects of eicosanoids derived from different 20-carbon fatty acids on T helper type 1 and T helper type 2 cytokine production in human whole-blood cultures.

BACKGROUND: Different series prostaglandins (PGs) and leukotrienes (LTs) are synthesized from different 20 carbon fatty acid precursors. The effects of the different series of PGs and LTs on production of T helper type 1 (Th1) and Th2 cytokines by human cells are not well established. OBJECTIVE: To characterize the influence of PGs and LTs produced from different fatty acid precursors on the Th1 and Th2 cytokine profile in mitogen-stimulated human whole-blood cultures. METHODS: Blood from healthy adult males was diluted and cultured with concanavalin A in the presence or absence of a range of concentrations of various PGs or LTs. Cytokine concentrations in culture supernatants were analysed by enzyme-linked immunosorbent assay (ELISA). RESULTS: PGE1, PGE2 and PGE3 significantly and dose-dependently decreased the concentrations of the Th1 cytokines IL-2 and IFN-gamma by up to 50% and 70%, respectively. The three PGs exhibited similar potency towards IFN-gamma production. At the highest concentration used (10-6 m) PGE1, but not PGE2 or PGE3, increased the concentration of the Th2 cytokine IL-4 by about 70%. IL-10 production was not affected by PGs. The ratio of the concentrations of IFN-gamma to IL-4 was significantly decreased at PGE concentrations of 10-7 and 10-6 M with all three PGEs having similar effects. LTB4, LTC4 and LTC5 did not significantly affect production of the cytokines studied. CONCLUSION: PGE produced from different fatty acids significantly decrease Th1 cytokine production resulting in a shift in the Th1, Th2 balance in favour of a Th2 response. PGE produced from different fatty acid precursors are equipotent in their effects on human T lymphocytes. Thus, although changes in the pattern of dietary fatty intakes may contribute to the increased prevalence of atopic disease, this would probably not be mediated through substitution of one PGE with another from a different series. It may, however, be mediated through a change in the total amount of PGE produced at the site of antigen presentation.

An exploration into the role of the teacher/lecturer in practice: findings from a case study in adult nursing.

Against a background of increasing concern over the widening theory practice gap and research evidence of problems in providing quality practice education, the English National Board (ENB) commissioned an 18 month study into the role of the teacher/lecturer in practice. This article, after providing a brief overview of the background, literature and methods, outlines the results from the Adult Case Study stage of the research. Documents, individual and focus group interviews of lecturers (n = 76), practitioners (n = 46) and students (n = 131) in five schools of nursing and midwifery provided data for analysis. A role labeled as 'link lecturer' was the most common approach acknowledged by all respondent groups. Despite overt commitment to the practice role by schools of nursing and midwifery, findings indicate that lecturers are unprepared, unsupported and unmonitored. Students and practitioners had very variable experiences and expressed a strong need for a better-organized approach which would provide them with consistent and sustained support in the practice setting. Overall the study highlighted a lack of strategic management of the practice role by university schools of nursing and midwifery. Convergence of findings from midwifery and the other branches of nursing provides strong research evidence for recommendations for more active management of the practice curriculum to be implemented as part of any future proposed reforms for nurse education in the UK.

Infusion of vincristine and doxorubicin with oral dexamethasone as first-line therapy for multiple myeloma.

32 previously untreated patients with multiple myeloma received vincristine, doxorubicin ('Adriamycin'), and dexamethasone (VAD) as first-line therapy. The overall response rate was 84%, with 28% of all patients entering complete remission. Response was rapid, with near-maximum response occurring after two courses of treatment and rapid improvement in bone-marrow function. Median response duration was 18 months and this seemed to be unaffected by initial prognostic criteria or by degree of remission achieved. The projected median survival was 44 months, with 75% of all patients and 83% of responders being alive at 2 years. Side-effects due to steroids were common, but there was only 1 treatment-related death. The high response rate and lack of toxicity offer an advantage over other forms of initial treatment, although other strategies will be necessary to prolong the duration of response.

Behavioral and psychiatric assessment of preterm and full-term low birth weight children at 9-11 years of age.

Preterm (N = 33) and full-term (N = 18) low birth weight subjects were compared at age 9 to 11 years to 52 full-term normal birth weight subjects of similar age and socioeconomic levels. All groups were evaluated by a psychiatrist who was not aware of prenatal or perinatal histories at the time of the interview. Mothers completed various standardized questionnaires designed to elicit information about the children's behaviors. There were no significant differences among the groups in the numbers of subjects with diagnoses of psychiatric disorders or in scores on ratings of hyperactivity, general behavioral maladjustment, and specific behavioral factors. These results indicate that low birth weight per se does not portend serious psychiatric sequelae during middle childhood.

Relationship between minor physical anomalies, perinatal complications, and psychiatric diagnoses in children.

Thirty-three preterm infants of low birth weight, 18 full-term infants of low birth weight, and 52 full-term infants of normal birth weight were evaluated at ages 9 to 11 years for psychiatric diagnoses and for minor physical anomalies. Mothers completed various child behavior questionnaires. Analysis of variance of the mean anomaly scores revealed that significant differences in the scores were due to the presence or absence of perinatal complications other than low birth weight and preterm delivery. Significant differences were also related to the presence or absence of at least one psychiatric diagnosis. The variables of perinatal complications and psychiatric diagnoses seemed to be acting independently of each other. The minor physical anomaly scores also correlated significantly with Conners Parent-Teacher Questionnaire scores for hyperactivity in both the full-term normal birth weight group and the preterm low birth weight group.

Preterm birth, low birth weight, and hyperkinetic behavior in children.

We compared 54 children who were born either preterm or weighing less than 2,501 gm with 52 children born at term and weighing more than 2,500 gm. There were no significant differences in sex or racial distribution nor in socioeconomic status. After semistructured psychiatric interviews, four subjects from the preterm, low-birth-weight group and two subjects from the full-term, normal-birth-weight group were given a diagnosis of "hyperkinetic reaction" (not a significant difference). Scores on the Conners Parent-Teacher Questionnaire (PTQ) did not correlate with any birth-related variables, though subjects with psychiatric diagnoses tended to have greater PTQ scores.