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Auxin herbicide drift to susceptible soybean [Glycine max (L.) Merr.] and cotton (Gossypium hirsutum) cultivars are a significant concern. Additionally, the impact of auxin herbicide drift on pollinators' foraging sources, including soybean, needs to be understood. A field experiment was conducted in 2022 at the University of Arkansas at Pine Bluff Small Farm Outreach Center near Lonoke, Ark., to evaluate the effect of auxin herbicide simulated drift rates on soybean reproductive organs (flowers and pods), pollen grains, and grain yield. A randomized complete block design was implemented with 8 replications. Four herbicides [florpyrauxifen-benzyl (Loyant®), 2,4-D (Enlist® One), dicamba (Engenia®), and quinclorac (Facet®)] were used at 2 rates (1/100x and 1/1000x the labeled rate) except for quinclorac, applied only at 1/100x the labeled rate. Four random soybean plants were collected from each treatment at the R3 growth stage, and reproductive organs were counted. Soybean flowers were also collected for pollen quantification 1 d before anthesis, and soybean was harvested at physiological maturity. Results showed that simulated drift rates of dicamba and florpyrauxifen-benzyl decreased the total number of soybean reproductive organs, pollen grains, and grain yield compared to the untreated control. Dicamba and florpyrauxifen-benzyl applied at 1/100x of the labeled rate reduced the number of reproductive organs by 35% and 39% at R3 compared to the nontreated control. Dicamba and florpyrauxifen-benzyl applied at this rate decreased pollen grains produced per anther by 28% and 18%, respectively, compared to the nontreated control. Applications of dicamba and florpyrauxifen-benzyl at 1/100x of the labeled rate reduced soybean grain yield by 43% and 27%, respectively, compared to the nontreated control. In addition to grain yield reduction, these results show that simulated auxin herbicide drift rates negatively impact pollinators' foraging sources with decreased pollen grain production and reducing the total number of reproductive organs, further illustrating the need for drift mitigation strategies to be developed and implemented. [ABSTRACT FROM AUTHOR]

Reviton® (tiafenacil) is a new protoporphyrinogen oxidase (PPO)-inhibiting herbicide labeled for burndown applications. However, as burndown applications can be stretched across a wide range of dates in the mid-South, there is an increased potential for off-target movement onto emerged crops. As a result, research was needed to determine the effects of simulated drift rates of Reviton on soybean [Glycine max (L.) Merr.]. In 2022, an experiment was established in Newport, Ark., St. Joseph, La., Alexandria, La., and Milan, Tenn., to assess the tolerance of soybean to simulated drift rates of Reviton herbicide when exposed at the V2 soybean growth stage. Reviton simulated drift rates of 1/8, 1/16, 1/32, 1/64, 1/128, and 1/256 of the labeled rate (1 fl oz./ac) were applied to determine the potential consequences of off-target movement. The higher simulated drift rates of Reviton (1/8x and 1/16x) caused greater visual injury (greater than 60% 2 weeks after application), height reduction (approximately 36% reduction 4 weeks after application), and yield reduction (55% and 26% reduction for the 1/8x and 1/16x rates, respectively) compared to other rates. These results suggest soybean growers should be concerned about Reviton drift onto their soybean crop, and appropriate measures should be taken to reduce off-target movement of Reviton to avoid soybean growth and yield reductions. [ABSTRACT FROM AUTHOR]

In U. S. cotton production systems, Palmer amaranth [Amaranthus palmeri (S.) Wats.] is the most problematic weed and can reduce yield and harvest efficiency. Palmer amaranth emerges and thrives in cotton, where canopy closure is prolonged relative to other row-crops grown in the mid-South. In 2018, at the University of Arkansas System Division of Agriculture's Lon Mann Cotton Research and Extension Station near Marianna, Arkansas, a trial was initiated to evaluate the long-term implications of integrated weed management strategies on Palmer amaranth emergence. The experiment took place over four years with plots located in the same test site. The experiment consisted of 16 treatments with 4 replications comparing multiple weed management strategies alone and in combination: deep tillage, a cereal rye cover crop, zero-tolerance, and a dicamba-based weed control program or a standard glufosinate program. Averaged over the first four years of the study, using zero tolerance, a cereal rye cover crop, or a plow event reduced Palmer amaranth emergence by 56%, 58%, and 63%, respectively. When a plow event was combined with a dicamba-based herbicide program or when a plow event, a dicamba-based program, and cover crop were utilized, Palmer amaranth emergence was reduced by 93%. Using a plow event plus a dicamba-based herbicide program or using a one-time plow event in combination with a dicamba-based program and a cover crop had the greatest reduction of Palmer amaranth emergence over the four-year period. [ABSTRACT FROM AUTHOR]

The use of Enlist®, XtendFlex®, and LibertyLink® cropping systems are effective tools to facilitate weed management in cotton (Gossypium hirsutum L.). These technologies enable farmers to use 2,4-D, dicamba, or glufosinate over the top of cotton in season. However, the incidence of Palmer amaranth (Amaranthus palmeri S. Wats.) escapes demonstrates the importance of surveilling the spread of herbicide resistance. Therefore, this study aimed to evaluate herbicide resistance in Palmer amaranth accessions collected after glufosinate and auxin mimic herbicides (2,4-D or dicamba) were applied for weed control. A total of 22 accessions from eastern Arkansas were collected in the 2021 growing season. Herbicide treatments were equivalent to 0.5× or 1× rate of 2,4-D (Enlist One®) at 0.48 and 0.95 lb ae/ac, dicamba (XtendiMax®) at 0.25 and 0.5 lb ae/ac, and glufosinate (Liberty®) at 0.29 and 0.58 lb ai/ac, respectively. All treatments were applied to greenhouse-grown Palmer amaranth plants with 5 to 6 leaves, and 2 runs of 50 plants per accession were sprayed per treatment. Plant mortality (%) was assessed 21 days after treatment. Treatments with 2,4-D, dicamba, and glufosinate at 0.5× resulted in 80% or less mortality to 18, 13, and 6 accessions, respectively. Treatments with a 1× rate provided more than 80% control to all accessions treated with dicamba; meanwhile, only 18 and 21 accessions treated with 2,4-D and glufosinate, respectively, resulted in the same level of mortality. 2 accessions that resulted in less than 60% mortality after treatment with a 1× rate of 2,4-D were further evaluated, and resistance to 2,4-D was confirmed. These findings demonstrate the importance of monitoring weed survival in production fields. Implementing integrated weed management strategies to reduce selective pressure over current herbicide options could help mitigate herbicide resistance cases. [ABSTRACT FROM AUTHOR]

One of the best management practices for reducing postemergence selection for Palmer amaranth [Amaranthus palmeri (S.) Wats.] is the use of soil-applied herbicides. To evaluate the incidence of activating rainfall on residual herbicide activity and performance with single preemergence applications of Alite 27®, Dual Magnum®, Valor®, XtendiMax®, and Zidua®), five bare ground experiments were conducted in 2021 and 2022 in Fayetteville, Ark. Treatments were arranged as a single-factor (herbicide) randomized complete block design with four replications. In addition to visible weed control evaluations, a WatchDog® weather station was placed in the field to monitor rainfall for each 28-day experiment. For most of the evaluated herbicides, a delayed activating rainfall reduced initial weed control over instances where immediate (within a few days) activation occurred. At 14 days after treatment (DAT), without adjusting for rainfall, box and whisker plots indicate that 3 out of 5 herbicides have minimal variation with comparable levels of Palmer amaranth control (above 85%). Greater variation in control was observed with Alite 27 and XtendiMax, with data points as low as 50 and 40%, respectively. Trends in the results at 28 DAT were similar to 14 DAT; however, variation in control began to increase for all herbicides, which indicated that the environment influenced the residual activity over time. Overall, rainfall soon after an XtendiMax application reduced performance, unlike the other herbicides evaluated. For most soil-applied herbicides, choosing the appropriate herbicide and timeliness of an activating irrigation event is imperative to optimize weed control. [ABSTRACT FROM AUTHOR]

Resistance to glufosinate in Palmer amaranth (Amaranthus palmeri S. Wats.) was first reported in 2021 in Arkansas. Alternative chemical control methods are highly sought to avoid the spread of this problematic herbicide-resistant weed across the southern region of the United States. This study aimed to determine the effectiveness of herbicides labeled for preplant or preemergence applications in cotton (Gossypium hirsutum L.) and soybean (Glycine max L.) to control glufosinate-resistant Palmer amaranth. The preemergence (PRE) treatments were imazaquin (0.12 lb ai/ac), pendimethalin (1 lb ai/ac), diuron (1 lb ai/ac), metribuzin (0.67 lb ai/ac), flumioxazin (0.063 lb ai/ac), saflufenacil (0.045 lb ai/ac), fomesafen (0.25 lb ai/ac), trifludimoxazin (0.045 lb ai/ac), acetochlor (1.124 lb ai/ac), S-metolachlor (1.24 lb ai/ac), pyroxasulfone (0.129 lb ai/ac), and fluridone (0.15 lb ai/ac). Irrigation in the amount of 1 inch was applied after application to ensure the activation of herbicides. A postemergence (POST) treatment with glufosinate at 0.585 lb ai/ac was applied twenty days after preemergence treatments to confirm the presence of a glufosinate-resistant accession in the trial site. A randomized complete block design with 4 replicates was used with a nontreated control for comparison. Visual control (%) was rated, and aboveground biomass was collected 6 weeks after PRE treatments. Biomass reduction (%) was calculated in comparison to the nontreated control. The lowest visual control and biomass reduction were observed in treatments that received only glufosinate POST or imazaquin preemergence due to resistance to these herbicides. Low control and biomass reduction were also detected following the treatment with pendimethalin. Besides the herbicides mentioned above, visual control and biomass reduction rates were similar for all other herbicides. Although most of the tested herbicides provided acceptable Palmer amaranth control, overlapping multiple effective residual herbicides and POST-applied options are crucial to controlling glufosinate-resistant populations. [ABSTRACT FROM AUTHOR]

Many employing organizations in the United Kingdom and elsewhere are finding it increasingly important to have an effective strategy for recruiting and developing higher education graduates. Numerous external and internal factors affect employers' graduate recruitment and development strategies. The following main approaches to graduates' entry into organizations have been identified: (1) high-potential corporate management schemes; (2) elite functional or business unit streams within wider entry; (3) professional or functional schemes; (4) direct job entry; and (5) ad hoc recruitment. Although each approach has distinct features, their individual distinctiveness has blurred in recent years. The three main activities in a graduate strategy are as follows: planning demand; recruitment and selection; and managing entry, training, and development. The Institute of Employment Studies developed a Graduate Value Chain that explored each activity and identified emerging key issues, including the following: (1) aligning graduate strategy with the varied business needs for graduates; (2) relating needs and entry approaches to the increasingly diverse supply of graduates; (3) the need to make the best use of e-recruitment; (4) development of an "umbrella approach"; (5) attracting and developing high-potential graduates; (6) avoiding overselling on the graduate development promise; and (7) deciding on the right balance between the center and the line. (Contains 54 references.) (MN)

Retention of college graduates by employers across the United Kingdom was examined. Data were collected through a survey of 362 organizations and interviews with 36 employers and their graduate employees. Most employers were unworried by their levels of graduate retention; two-thirds expected to keep new recruits for the foreseeable future. Rates of retention of graduates averaged 86% after 3 years. Although one-third of the employers surveyed had managed to retain their entire graduate intake 1 year after appointment, approximately one-fourth of employers lost up to 50% of their intake within 1 year. Small employers had the highest average retention rate. Retention rates were lowest among employers recruiting to general roles rather than to those reserved for graduates or those involving formal and/or professional training. Employers offering higher starting salaries had the best retention rates. The overall market appeared stable, and starting salaries were predicted to grow slowly over the upcoming year. More than 40% of employers lacked any form of monitoring system that might provide insights into why graduates leave. The most popular techniques used for retaining graduates were offering technical professional training, offering mentoring/coaching, and providing planned career and/or salary progression. (Seventeen tables/figures are included. The bibliography lists 16 references. Nine additional benchmarking tables are appended.) (MN)

Italian ryegrass [Lolium perenne L. ssp. multiflorum (Lam.) Husnot] has become more problematic and difficult to control because it is resistant to multiple herbicides. Fall-applied residual herbicides have effectively controlled other winter annual weeds and could be another option in controlling Italian ryegrass. The objective of this study was to evaluate multiple residual herbicides for the control of Italian ryegrass in the fall and the following spring before planting soybean [Glycine max (L.) Merr.]. Before any weed emergence, a field experiment was initiated at the University of Arkansas System Division of Agriculture's Jackson County Extension Center near Newport, Ark., in the fall of 2021. Treatments in this experiment consisted of Anthem® Flex (4 fl oz/ac), Command® (20 fl oz/ac), Dual Magnum® (1.33 pt/ac), Outlook® (16 fl oz/ac), Prowl® (2.1 pt/ac), Treflan® (2 pt/ac), Warrant® (2.5 pt/ac), Warrant® (5 pt/ac), and Zidua® SC (3.75 fl oz/ac). Initial visual control of Italian ryegrass 14 days after application (DAA) (28 Oct. 2021) exceeded 95% for every herbicide treatment except for Prowl and the low rate of Warrant. Only Zidua SC, Anthem Flex, and Dual Magnum retained effective residual control at 60 DAA (13 Dec. 2021) (>95%) and 166 DAA (29 March 2022) (>90%). Overall, using Zidua SC, Anthem Flex, and Dual Magnum herbicides were the most effective options to control Italian ryegrass in the fall and following spring before planting soybean. These fall-applied treatments would improve overall Italian ryegrass management and delay the evolution of resistance to postemergence herbicides. [ABSTRACT FROM AUTHOR]