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Field trials were conducted near Pontotoc, Mississippi; Chase, Louisiana; and Clinton, North Carolina, in 2017 and 2018 to determine the effect of pendimethalin rate and timing application on sweetpotato crop tolerance, yield, and storage root quality. Treatments consisted of five pendimethalin rates (266, 532, 1,065, 1,597, and 2,130 g ai ha−1) by two application timings (0 to 1 or 10 to 14 d after transplanting). Additionally, a nontreated check was included for comparison. Crop injury (stunting) was minimal (≤4%) through 6 wk after transplanting (WAP) and no injury was observed from 8 to 14 WAP, regardless of application timing or rate. The nontreated check yielded 6.6, 17.6, 5.5, and 32.1 × 103 kg ha−1 of canner, no. 1, jumbo, and total grades, respectively. Neither pendimethalin application timing nor rate influenced jumbo, no. 1, marketable, or total sweetpotato yield. Overall, these results indicate that pendimethalin will be a valuable addition to the toolkit of sweetpotato growers.
A national need is to prepare for and respond to accidental or intentional disasters categorized as chemical, biological, radiological, nuclear, or explosive (CBRNE). These incidents require specific subject-matter expertise, yet have commonalities. We identify 7 core elements comprising CBRNE science that require integration for effective preparedness planning and public health and medical response and recovery. These core elements are (1) basic and clinical sciences, (2) modeling and systems management, (3) planning, (4) response and incident management, (5) recovery and resilience, (6) lessons learned, and (7) continuous improvement. A key feature is the ability of relevant subject matter experts to integrate information into response operations. We propose the CBRNE medical operations science support expert as a professional who (1) understands that CBRNE incidents require an integrated systems approach, (2) understands the key functions and contributions of CBRNE science practitioners, (3) helps direct strategic and tactical CBRNE planning and responses through first-hand experience, and (4) provides advice to senior decision-makers managing response activities. Recognition of both CBRNE science as a distinct competency and the establishment of the CBRNE medical operations science support expert informs the public of the enormous progress made, broadcasts opportunities for new talent, and enhances the sophistication and analytic expertise of senior managers planning for and responding to CBRNE incidents.
Background: SMA is a neurodegenerative disease caused by biallelic deletion/mutation of the survival motor neuron (SMN1) gene. In the phase 1 trial (NCT02122952), SMN GRT onasemnogene abeparvovec (AVXS-101) improved outcomes of 15 symptomatic SMA1 patients (3 at a lower dose [cohort 1] and 12 at the proposed therapeutic dose [cohort 2]). This report describes long-term follow-up study design and data from the phase 1 study. Methods: Patients in the phase 1 study could rollover into a long-term follow-up study (NCT03421977). The primary objective is to collect long-term safety data (serious adverse events, hospitalizations, and adverse events of special interest). Annual follow-up will occur for 15 years. Additionally, patient record transfers from local clinician(s) will be requested. Safety assessments include medical history and record review, physical examination, clinical laboratory evaluation, and pulmonary assessments. Efficacy assessments include physical examination to assess developmental milestones. Results: As of September 27, 2018, the oldest patients are 59.2 (cohort 1) and 52.1 (cohort 2) months old and free of permanent ventilation. Preliminary data, including survival and developmental milestones, will be presented. Conclusions: Patients treated with a one-time dose of AVXS-101 continue to gain strength, develop, and achieve new milestones, demonstrating a long-term, durable response.
Children with congenital heart disease are at high risk for malnutrition. Standardisation of feeding protocols has shown promise in decreasing some of this risk. With little standardisation between institutions’ feeding protocols and no understanding of protocol adherence, it is important to analyse the efficacy of individual aspects of the protocols.
Adherence to and deviation from a feeding protocol in high-risk congenital heart disease patients between December 2015 and March 2017 were analysed. Associations between adherence to and deviation from the protocol and clinical outcomes were also assessed. The primary outcome was change in weight-for-age z score between time intervals.
Increased adherence to and decreased deviation from individual instructions of a feeding protocol improves patients change in weight-for-age z score between birth and hospital discharge (p = 0.031). Secondary outcomes such as markers of clinical severity and nutritional delivery were not statistically different between groups with high or low adherence or deviation rates.
High-risk feeding protocol adherence and fewer deviations are associated with weight gain independent of their influence on nutritional delivery and caloric intake. Future studies assessing the efficacy of feeding protocols should include the measures of adherence and deviations that are not merely limited to caloric delivery and illness severity.
Introduction: Abdominal pain is one of the most frequent reasons for an emergency department (ED) visit. Most cases are functional and no therapy has proven effective. Our objective was to determine if hyoscine butylbromide (HBB) (BuscopanTM) is effective for children who present to the ED with functional abdominal pain. Methods: We conducted a randomized, blinded, superiority trial comparing HBB 10 mg plus acetaminophen placebo to oral acetaminophen 15 mg/kg (max 975 mg) plus HBB placebo using a double-dummy approach. We included children 8-17 years presenting to the ED at London Health Sciences Centre with colicky abdominal pain rated >40 mm on a 100 mm visual analog scale (VAS). The primary outcome was VAS pain score at 80 minutes post-administration. Secondary outcomes included adverse effects; caregiver satisfaction with pain management using a five-item Likert scale; recidivism and missed surgical diagnoses within 24-hours of discharge. Analysis was based on intention to treat. Results: We analyzed 225 participants (112 acetaminophen; 113 HBB). The mean (SD) age was 12.4 (3.0) years and 148/225 (65.8%) were females. Prior to enrollment, the median (IQR) duration of pain prior was 2 (4.5) hours and analgesia was provided to 101/225 (44.9%) of participants. The mean (SD) pre-intervention pain scores in the acetaminophen and HBB groups were 62.7 (15.9) mm and 60.3 (17.3) mm, respectively. At 80 minutes, the mean (SD) pain scores in the acetaminophen and HBB groups were 30.1 (28.8) mm and 29.4 (26.4) mm, respectively and there were no significant differences adjusting for pre-intervention scores (p = 0.96). The median (IQR) caregiver satisfaction was high in the acetaminophen [5 (2)] and HBB [5 (1)] groups (p = 0.79). The median (IQR) length of stay between acetaminophen [235 (101)] and HBB [234 (103)] was not significantly different (p = 0.53). The proportion of participants with a return visit for abdominal pain was 4/112 (3.5%) in the acetaminophen group and 6/113 (5.3%) in the HBB group. The most common adverse effect was nausea (9% in each group) and there were no significant differences in adverse effects between acetaminophen (26/112, 23.2%) and HBB (31/113, 27.4%) (p = 0.52). There were no missed surgical diagnoses. Conclusion: For children with presumed functional abdominal pain who present to the ED, both acetaminophen and HBB produce a clinically important (VAS < 30 mm) reduction in pain and should be routinely considered in this clinical setting.
Identifying routes of transmission among hospitalized patients during a healthcare-associated outbreak can be tedious, particularly among patients with complex hospital stays and multiple exposures. Data mining of the electronic health record (EHR) has the potential to rapidly identify common exposures among patients suspected of being part of an outbreak.
We retrospectively analyzed 9 hospital outbreaks that occurred during 2011–2016 and that had previously been characterized both according to transmission route and by molecular characterization of the bacterial isolates. We determined (1) the ability of data mining of the EHR to identify the correct route of transmission, (2) how early the correct route was identified during the timeline of the outbreak, and (3) how many cases in the outbreaks could have been prevented had the system been running in real time.
Correct routes were identified for all outbreaks at the second patient, except for one outbreak involving >1 transmission route that was detected at the eighth patient. Up to 40 or 34 infections (78% or 66% of possible preventable infections, respectively) could have been prevented if data mining had been implemented in real time, assuming the initiation of an effective intervention within 7 or 14 days of identification of the transmission route, respectively.
Data mining of the EHR was accurate for identifying routes of transmission among patients who were part of the outbreak. Prospective validation of this approach using routine whole-genome sequencing and data mining of the EHR for both outbreak detection and route attribution is ongoing.
Nutritional strategies to mitigate the negative effects of heat stress on animal welfare and productivity often involve changes in ration formulation. However, cattle commonly sort their ration in favour of certain components, and it is not clear how feed sorting responds to heat stress. This study investigated the association between heat stress and feed sorting behaviour. Lactating Holstein dairy cows (n = 32; parity = 2.8±1.2; mean±SD) were housed in a free stall barn and milked 3×/day. Cows were fed individually using the Calan Broadbent Feeding System and offered ad libitum access to a total mixed ration (containing on a dry matter basis: 3.3% ryegrass hay, 16.5% ryegrass baleage, 24.7% corn silage, 11.1% brewers grains, 19.7% ground corn, 19.8% concentrate and 4.9% protein/mineral supplement), provided 1×/day. Beginning at 186±60 days in milk, cows were exposed to either: heat stress conditions (HT; n = 15) (average temperature–humidity index: 77.6), or evaporative cooling (CL; n = 17), consisting of misters and fans over the freestall and feed bunks. Data were collected during a 4-day baseline period, and two 4-day experimental periods: starting at 10 days after implementing treatments (defined as acute heat stress for HT cows), and at 62 days after implementing treatments (defined as chronic heat stress for HT cows). Daily feed intake and physiological responses to heat stress (body temperature, respiration rate) were recorded. Samples of fresh and refused feed were collected daily from individual cows for particle size analysis. The particle size separator had three screens (19, 8 and 1.18 mm) and a bottom pan, resulting in 4 fractions (long, medium, short and fine particles). Feed sorting was calculated as the actual intake of each particle size fraction expressed as a percentage of the predicted intake of that fraction. During both heat stress periods, HT cows sorted for long particles more than CL cows (105.0% v. 100.6%; SE = 1.1). During acute heat stress, HT cows sorted to a greater extent than CL cows against medium and short particles, whereas sorting of these fractions did not differ during chronic heat stress. Body temperature and respiration rate were associated across treatments with the extent of sorting for long particles and against short particles during acute heat stress. These results suggest that feed sorting is particularly influenced during acute heat stress, and that sorting for longer particles may increase in heat stress.
Understanding how critical sow live-weight and back-fat depth during gestation are in ensuring optimum sow productivity is important. The objective of this study was to quantify the association between sow parity, live-weight and back-fat depth during gestation with subsequent sow reproductive performance. Records of 1058 sows and 13 827 piglets from 10 trials on two research farms between the years 2005 and 2015 were analysed. Sows ranged from parity 1 to 6 with the number of sows per parity distributed as follows: 232, 277, 180, 131, 132 and 106, respectively. Variables that were analysed included total born (TB), born alive (BA), piglet birth weight (BtWT), pre-weaning mortality (PWM), piglet wean weight (WnWT), number of piglets weaned (Wn), wean to service interval (WSI), piglets born alive in subsequent farrowing and sow lactation feed intake. Calculated variables included the within-litter CV in birth weight (LtV), pre-weaning growth rate per litter (PWG), total litter gain (TLG), lactation efficiency and litter size reared after cross-fostering. Data were analysed using linear mixed models accounting for covariance among records. Third and fourth parity sows had more (P<0.05) TB, BA and heavier BtWT compared with gilts and parity 6 sow contemporaries. Parities 2 and 3 sows weaned more (P<0.05) piglets than older sows. These piglets had heavier (P<0.05) birth weights than those from gilt litters. LtV and PWM were greater (P<0.01) in litters born to parity 5 sows than those born to younger sows. Sow live-weight and back-fat depth at service, days 25 and 50 of gestation were not associated with TB, BA, BtWT, LtV, PWG, WnWT or lactation efficiency (P>0.05). Heavier sow live-weight throughout gestation was associated with an increase in PWM (P<0.01) and reduced Wn and lactation feed intake (P<0.05). Deeper back-fat in late gestation was associated with fewer (P<0.05) BA but heavier (P<0.05) BtWT, whereas deeper back-fat depth throughout gestation was associated with reduced (P<0.01) lactation feed intake. Sow back-fat depth was not associated with LtV, PWG, TLG, WSI or piglets born alive in subsequent farrowing (P>0.05). In conclusion, this study showed that sow parity, live-weight and back-fat depth can be used as indicators of reproductive performance. In addition, this study also provides validation for future development of a benchmarking tool to monitor and improve the productivity of modern sow herd.
Dietary fatty acid (FA) composition may influence metabolism, possibly affecting weight management. The purpose of this study was to compare the effects of a 5-d diet rich in PUFA v. MUFA. A total of fifteen normal-weight men participated in a randomised cross-over design with two feeding trials (3 d lead-in diet, pre-diet visit, 5-d PUFA- or MUFA-rich diet, post-diet visit). The 5-d diets (50 % fat) were rich in either PUFA (25 % of energy) or MUFA (25 % of energy). At pre- and post-diet visits, subjects consumed breakfast and lunch test meals, rich in the FA for that 5-d diet. Indirect calorimetry was used for 4 h after each meal. There were no treatment differences in fasting metabolism acutely or after the 5-d diet. For acute meal responses before diet, RER was higher for PUFA v. MUFA (0·86 (sem 0·01) v. 0·84 (sem 0·01), P<0·05), whereas diet-induced thermogenesis (DIT) was lower for PUFA v. MUFA (18·91 (SEM 1·46) v. 21·46 (SEM 1·34) kJ, P<0·05). After the 5-d diets, the change in RER was different for PUFA v. MUFA (−0·02 (sem 0·01) v. 0·00 (sem 0·01), P<0·05). Similarly, the change in fat oxidation was greater for PUFA v. MUFA (0·18 (sem 0·07) v. 0·04 (sem 0·06) g, P<0·05). In conclusion, acutely, a MUFA-rich meal results in lower RER and greater DIT. However, after a 5-d high-fat diet, the change in metabolic responses was greater in the PUFA diet, showing the metabolic adaptability of a PUFA-rich diet.
Florpyrauxifen-benzyl is a new synthetic auxin herbicide that will provide a novel site of action in rice production. In many areas of the United States it is common practice to plant soybeans in rotation with rice, thereby introducing the potential for herbicide carryover. Multiple field experiments were conducted in 2014 and repeated in 2015 to evaluate potential plant-back restrictions for soybean and other row crops following an application of florpyrauxifen-benzyl. In the first experiment, treatments comprised florpyrauxifen-benzyl applied at 40 followed by 40 g ai ha–1, 80 fb 80 g ai ha–1, and a nontreated check. In 2014, herbicides were applied to a silt loam soil near Stuttgart and Colt, AR, and fields remained fallow following application. The following year, corn, cotton, soybean, grain sorghum, and sunflower were planted within the previously treated area. Stand counts, crop heights, and visual injury assessments were done for each crop following planting, and aboveground biomass data were collected 28 d after planting. No significant differences were observed among the treatments for any of the parameters assessed, highlighting the rotational flexibility of common row crops 1 yr following a florpyrauxifen-benzyl application. In the second experiment, florpyrauxifen-benzyl was applied at 30 and 60 g ai ha–1 at 56, 28, 14, and 0 d before planting soybean. Injury assessments corresponded to the highest concentration of florpyrauxifen-benzyl and its metabolites recovered from soil at the time of planting. Conversely, soybean injury was reduced when florpyrauxifen-benzyl was applied at increasing intervals before planting. At the end of each season, soybean yield was similar to the nontreated control when florpyrauxifen-benzyl at 30 or 60 g ai ha–1 was applied 56 d before planting, whereas all other treatments reduced yield. These results support a relatively short replant interval for soybean after florpyrauxifen-benzyl application to rice.
Florpyrauxifen-benzyl is a new active ingredient that represents an additional tool in rice (Oryza sativa L.) weed control by providing an alternative mechanism of action. Studies were conducted to evaluate soil moisture influences on florpyrauxifen-benzyl absorption, translocation, and metabolism in three problematic weeds. In the absorption/translocation study, barnyardgrass [Echinochloa crus-galli (L.) P. Beauv.], hemp sesbania [Sesbania herbacea (Mill.) McVaugh], and yellow nutsedge (Cyperus esculentus L.) were treated with [14C]florpyrauxifen-benzyl under two soil moisture regimes (7.5% and 60% field capacity). Greater absorption occurred under moist conditions (60% soil moisture content). More translocation of the herbicide to the area above the treated leaf occurred under moist versus dry soil across all weed species. Sesbania herbacea translocated 25% of the absorbed herbicide above the treated leaf, a result greater than that of the other two weed species at 60% soil moisture. However, no differences in translocation occurred among the weed species at the 7.5% soil moisture regime. In the metabolism study, 95% of the herbicide recovered was in its acid form under the high soil moisture regime for S. herbacea, a species that shows extreme sensitivity to even low doses of this herbicide, and soil moisture influenced the amount of acid form found in all species. While these data provide a limited view into the physiological processes being affected, they do suggest that for E. crus-galli, S. herbacea, and C. esculentus, soil moisture content in the field will likely play a significant role in absorption, translocation, and metabolism of florpyrauxifen-benzyl.
In a greenhouse experiment, soybean, cotton, corn, grain sorghum, and sunflower were subjected to 1/10 (3 g ai ha-1), 1/100 (0.3 g ai ha-1), or 1/500 (0.06 g ai ha-1) of the 1X rate of florpyrauxifen-benzyl. Visible injury 14 days after treatment (DAT) was the greatest with soybean (96%) when exposed to the highest drift rate of 1/10x or 3 g ai/ha-1 of florpyrauxifen-benzyl and was significantly higher than all other crops and drift rates. Cotton and sunflower were also injured 85 and 83%, respectively, by the 1/10x rate but had less injury when a 1/100x or 1/500x rate was applied (injury ranging from 9 to 33%). It was concluded that the negative effects on soybean, cotton, and sunflower primarily resulted from exposure to the highest rate tested (1/10x) and only soybean expressed negative effects even at the lower rate of 1/100x. A field study was also conducted to (1) evaluate the sensitivity of soybean to low concentrations of florpyrauxifen-benzyl during vegetative and reproductive development and (2) compare soybean injury and yield following applications of florpyrauxifen-benzyl and dicamba across various growth stages and concentrations. Soybean plants were treated with 1/10, 1/20, 1/40, 1/80, 1/160, 1/320, or 1/640 of the 1X rate of florpyrauxifen-benzyl (30 g ai/ ha-1) or dicamba (560 g ae ha-1) at the V3 and R1 growth stage. Florpyrauxifen-benzyl applied at a rate of 1/10 to 1/40X caused foliar injury and subsequent height reduction. In comparison, dicamba applied at the same rates caused slightly less injury and growth reductions. As rate of florpyrauxifen-benzyl decreased from 1/10 to 1/640X, the level of soybean injury dissipated rather quickly. However, this was not the case with dicamba, as substantial injury was observed with rates as low as 1/640X.
Background: Longitudinal data on health-related quality of life (HRQOL) and fatigue in paediatric Duchenne muscular dystrophy (DMD) are limited. Recently, fatigue was reported to be the greatest predictor of poor HRQOL in paediatric DMD. Understanding the trajectory of HRQOL and its relationship with fatigue may facilitate the development of improved therapeutic strategies. Our objective was to describe three-year changes in HRQOL and fatigue in children with DMD. Methods: Patients identified via the Canadian Neuromuscular Disease Registry received mailed questionnaires (2013–2016). HRQOL was assessed using the PedsQLTM GCS and NMM domains, and fatigue was assessed using the MFS domain (patient- and parent-report). Mean three-year change in scores were computed. Pearson correlations were computed between three-year change in HRQOL and fatigue. Results: Mean decline in MFS scores for patient- and parent-reports were 1.03 and 1.19, respectively. Mean decline in GCS scores for patient- and parent-report were 1.75 and 4.13, respectively. Mean change in NMM scores for patient- and parent-report were 0.72 and -8.36, respectively. Change in MFS score was associated with changes in GCS (r=0.72, p<0.001) and NMM scores (r=0.84, p<0.001) by patient-report. Conclusions: Children with DMD experience worse fatigue and HRQOL over time. Parents perceive a greater decline in HRQOL over time compared to patients.
We present early results from the first near-IR imaging of the weak X-ray sources discovered in the recent Chandra/ACIS-I survey towards the Galactic Centre (GC) (Wang et al. 2002). These ~800 discrete sources, which contribute significantly to the GC X-ray emission, represent an important and previously unknown population within the Galaxy. From our VLT observations we will identify likely IR counterparts to a sample of the hardest sources, which are most likely X-ray binaries. With these data we can place constraints on the nature of the discrete weak X-ray source population of the GC. Once the data analysis is complete we will discuss our results in the context of binary population synthesis models.
Florpyrauxifen-benzyl is a new herbicide being developed for rice. Research is needed to understand its spectrum of control and optimal tank-mix partners. Multiple greenhouse and field experiments were conducted to evaluate florpyrauxifen-benzyl efficacy and tank-mix compatibility. In greenhouse experiments, florpyrauxifen-benzyl at 30 g ai ha–1 provided ≥75% control of all weed species evaluated (broadleaf signalgrass, barnyardgrass, Amazon sprangletop, large crabgrass, northern jointvetch, hemp sesbania, pitted morningglory, Palmer amaranth, yellow nutsedge, rice flatsedge, smallflower umbrellasedge), and control was similar to or better than other herbicide options currently available in rice. Barnyardgrass was controlled 97% with florpyrauxifen-benzyl at 30 g ha–1, ultimately reducing height (86%) and aboveground biomass (84%). In these field studies at 30 g ha–1, no antagonism was observed when florpyrauxifen-benzyl was tank-mixed with contact (acifluorfen, bentazon, carfentrazone, propanil, and saflufenacil) or systemic (2,4-D, bispyribac, cyhalofop, fenoxaprop, halosulfuron, imazethapyr, penoxsulam, quinclorac, and triclopyr) rice herbicides. Although not every tank-mix or weed species was evaluated, the lack of antagonistic interactions herein highlights the flexibility and versatility of this new herbicide. Once florpyrauxifen-benzyl becomes commercially available, it will be beneficial to tank-mix this new herbicide with others without sacrificing efficacy, so as to apply multiple sites of action together and thus lessen the risk for evolution of herbicide resistance.
To investigate the association of policy, systems and environmental factors with improvement in household food security among low-income Indiana households with children after a Supplemental Nutrition Assistance Program-Education (SNAP-Ed) direct nutrition education intervention.
Household food security scores measured by the eighteen-item US Household Food Security Survey Module in a longitudinal randomized and controlled SNAP-Ed intervention study conducted from August 2013 to April 2015 were the response variable. Metrics to quantify environmental factors including classification of urban or rural county status; the number of SNAP-authorized stores, food pantries and recreational facilities; average fair market housing rental price; and natural amenity rank were collected from government websites and data sets covering the years 2012–2016 and used as covariates in mixed multiple linear regression modelling.
Thirty-seven Indiana counties, USA, 2012–2016.
SNAP-Ed eligible adults from households with children (n 328).
None of the environmental factors investigated were significantly associated with changes in household food security in this exploratory study.
SNAP-Ed improves food security regardless of urban or rural location or the environmental factors investigated. Expansion of SNAP-Ed in rural areas may support food access among the low-income population and reduce the prevalence of food insecurity in rural compared with urban areas. Further investigation into policy, systems and environmental factors of the Social Ecological Model are warranted to better understand their relationship with direct SNAP-Ed and their impact on diet-related behaviours and food security.
Disease in a pig herd can have major economic impacts, hampering agricultural processes and creating barriers to trade. Importantly, an outbreak of disease can also pose a risk to human health. It is currently unknown what effects different rearing regimes might have on the incidences of zoonoses in pigs. Outdoor rearing of pigs has gained popularity recently due to interest in animal welfare and an increase in the marketability of organic food. But it is unknown if outdoor rearing can alter the gut microbiology of pigs, and if pigs reared outdoors are more susceptible to zoonotic infections. A method for analysing bacterial populations present in the pig gut has been developed based on amplification of the 16S ribosomal DNA. This technique, known as Terminal Restriction Fragment Length Polymorphism (T-RFLP) analysis has been used for studying bacterial populations in environments such as soil (Osborn et al., 2000) and faeces (Li et al., 2007). It uses fluorescently labelled forward and reverse primers to generate labelled amplicons, followed by a restriction endonuclease digest of the amplified DNA to give rise to labelled terminal fragments that vary between different species. These terminal fragments are then detected using electrophoretic separation and laser detection, and identified based on the fragment size. This study aims to develop a protocol for using this technique on pure cultures of control organisms.
Florpyrauxifen-benzyl is a new herbicide under development in rice that will provide an alternative mode of action to control barnyardgrass. Multiple greenhouse experiments evaluated florpyrauxifen-benzyl efficacy on barnyardgrass accessions collected in rice fields across Arkansas, and to evaluate its efficacy on herbicide-resistant biotypes. In one experiment, florpyrauxifen-benzyl was applied at the labeled rate of 30 g ai ha−1 to 152 barnyardgrass accessions collected from 21 Arkansas counties. Florpyrauxifen-benzyl at 30 g ai ha−1 effectively controlled barnyardgrass and subsequently reduced plant height and aboveground biomass. In a dose-response experiment, susceptible-, acetolactate synthase (ALS)-, propanil-, and quinclorac-resistant barnyardgrass biotypes were subjected to nine rates of florpyrauxifen-benzyl ranging from 0 to 120 g ai ha−1. The effective dose required to provide 90% control, plant height reduction, and biomass reduction of the susceptible and resistant biotypes fell below the anticipated labeled rate of 30 g ai ha−1. Based on these results, quinclorac-resistant barnyardgrass as well as other resistant biotypes can be controlled with florpyrauxifen-benzyl at 30 g ai ha−1. Overall, results from these studies indicate that florpyrauxifen-benzyl can be an effective tool for controlling susceptible and currently existing herbicide-resistant barnyardgrass biotypes in rice. Additionally, the unique auxin chemistry of florpyrauxifen-benzyl will introduce an alternative mechanism of action in rice weed control thus acting as an herbicide-resistance management tool.
To address recent concerns related to auxin herbicide drift onto soybean, a study was developed to understand the susceptibility of the reproductive stage of soybean to a new auxin herbicide compared with dicamba. Florpyrauxifen-benzyl is under development as the second herbicide in a new structural class of synthetic auxins, the arylpicolinates. Field studies were conducted to (1) evaluate and compare reproductive soybean injury and yield following applications of florpyrauxifen-benzyl or dicamba across various concentrations and reproductive growth stages and (2) determine whether low-rate applications of florpyrauxifen-benzyl or dicamba to soybean in reproductive stages would have similar effect on the progeny of the affected plants. Soybean were treated with 0, 1/20, or 1/160, of the 1X rate of florpyrauxifen-benzyl (30 g ai ha−1) or dicamba (560 g ae ha−1) at R1, R2, R3, R4, or R5 growth stage. Soybean plant height and yield was reduced from 1/20X dicamba across all reproductive stages. High drift rates (1/20X) of florpyrauxifen-benzyl also reduced soybean plant height >25% and yield across R1 to R4 stages. Germination, stand, plant height, and yield of the offspring of soybean plants treated with dicamba and florpyrauxifen-benzyl were significantly affected. Dicamba applied at a rate of 1/20X at R4 and R5 resulted in 20% and 35% yield reduction for the offspring, respectively. A similar reduction occurred from florpyrauxifen-benzyl applied at R4 and R5 at the 1/20X rate, resulting in 15% to 24% yield reduction for the offspring, respectively. Based on these findings, it is suggested that growers use caution when applying these herbicides in the vicinity of reproductive soybean.