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The Constitution of Ceylon2 confers on the Parliament of Ceylon full power ‘ to make laws for the peace, order and good government of the Island ’. Section 29 (4) of the Constitution provides that.
Weeds are one of the greatest challenges to snap bean (Phaseolus vulgaris L.) production. Anecdotal observation posits certain species frequently escape the weed management system by the time of crop harvest, hereafter called residual weeds. The objectives of this work were to (1) quantify the residual weed community in snap bean grown for processing across the major growing regions in the United States and (2) investigate linkages between the density of residual weeds and their contributions to weed canopy cover. In surveys of 358 fields across the Northwest (NW), Midwest (MW), and Northeast (NE), residual weeds were observed in 95% of the fields. While a total of 109 species or species-groups were identified, one to three species dominated the residual weed community of individual fields in most cases. It was not uncommon to have >10 weeds m−2 with a weed canopy covering >5% of the field’s surface area. Some of the most abundant and problematic species or species-groups escaping control included amaranth species such as smooth pigweed (Amaranthus hybridus L.), Palmer amaranth (Amaranthus palmeri S. Watson), redroot pigweed (Amaranthus retroflexus L.), and waterhemp [Amaranthus tuberculatus (Moq.) Sauer]; common lambsquarters (Chenopodium album L.); large crabgrass [Digitaria sanguinalis (L.) Scop.]; and ivyleaf morningglory (Ipomoea hederacea Jacq.). Emerging threats include hophornbeam copperleaf (Acalypha ostryifolia Riddell) in the MW and sharppoint fluvellin [Kickxia elatine (L.) Dumort.] in the NW. Beyond crop losses due to weed interference, the weed canopy at harvest poses a risk to contaminating snap bean products with foreign material. Random forest modeling predicts the residual weed canopy is dominated by C. album, D. sanguinalis, carpetweed (Mollugo verticillata L.), I. hederacea, amaranth species, and A. ostryifolia. This is the first quantitative report on the weed community escaping control in U.S. snap bean production.
Small-seeded vegetable crop production is challenged by poor emergence, stand establishment and canopy development, as well as a lack of effective weed control options. The potential use of plant growth regulators such as gibberellic acid (GA) could enhance early emergence and growth rates while potentially synchronizing weed germination with control tactics. In response, a controlled environment study was conducted to investigate the effects of GA on garden beet, cabbage, carrot, and onion. At 7 d after seeding (DAS) carrot emergence was greater when carrot seeds were treated with 2, 4, 8, 16, or 64 ppm GA compared with nontreated seeds. Total carrot emergence over the study period was 14% greater when seeds were treated with 4 ppm GA compared with nontreated seeds. Treatment of cabbage with as low as 2 to 4 ppm GA increased cabbage emergence rate and total plant emergence over the study period relative to nontreated seeds. Onion response to GA treatment was variable and unremarkable and was hypothesized to be influenced by seed dormancy because emergence was also low with the nontreated seeds. The GA rates that stimulated vegetable crop seed germination and emergence were then explored with three common weed species to determine whether a similar response was observed. If so, GA could be used to stimulate weed emergence in synchrony with management tactics. Palmer amaranth emergence was strongly affected by GA treatment, whereby the total number of emerged plants was 48% greater when 4 ppm GA was applied than in the nontreated check. Velvetleaf emergence at 3 DAS with the 4 and 8 ppm GA was 2.9 and 3.0 plants pot−1, respectively, compared to no emergence in the nontreated pots. Redroot pigweed emergence was not affected by GA treatment at any rate.
The influence of weeds on cranberry yield and quality is not well known and cannot be extrapolated from other cropping systems given the unique nature of both cranberry production and the weed species spectrum. The work presented here addresses this need with four common weed species across multiple production seasons and systems in Wisconsin, Massachusetts, and New Jersey: Carolina redroot, earth loosestrife, bristly dewberry, and polytrichum moss. The objectives were to use these representative species to quantify the impact of weed density, groundcover, and biomass on several cranberry yield components and related interactions with other cranberry pests, and to determine whether these relationships were consistent enough across seasons to be reliably used in weed management decision-making. The relationships between Carolina redroot and bristly dewberry growth measures and marketable cranberry yield were highly significant (P ≤ 0.001 in 12 of 13 regressions) and consistent across growing seasons, but not significant for similar regressions with earth loosestrife. In particular, the strong relationship between Carolina redroot and bristly dewberry visual groundcover observations and cranberry yield suggests a simple way for growers and crop scouts to reliably estimate yield loss. The relationship between polytrichum moss biomass and cranberry yield was also significant in both years, but not consistent between years. Weed competition also affected cranberry quality, in that Carolina redroot density was strongly related to the percentage of insect-damaged fruit and bristly dewberry growth reduced cranberry color development. On a practical level, this information can be used to educate growers, consultants, agrichemical registrants, and regulators about the impacts of weeds on cranberry yield and quality, and to economically prioritize management efforts based on the weed species and extent of infestation.
The ability to use the protoporphyrinogen oxidase (PPO)-inhibiting herbicides fomesafen, flumioxazin, and sulfentrazone in potato is limited regionally or by soil texture, largely because of crop injury noted in research in the 1990s. With that in mind, we evaluated whether reducing the herbicide rates could maintain weed control while providing more consistent crop safety. Studies were conducted on a silt loam and a coarse-textured loamy sand soil. Soil texture played a greater than anticipated role in PPO-inhibitor herbicide injury risk as it relates to high-precipitation events. For example, in 2020 at the silt loam location, there were five precipitation events across the season that exceeded 2.5 cm, including one 6 d after treatment (DAT), and a seasonal total precipitation that was over 10 cm greater than the previous year. Despite excessive moisture and initial potato injury as high as 27% where flumioxazin was applied at the high rate with S-metolachlor, by 29 DAT injury was less than 10% in all treatments, and marketable tuber yield was similar among treatments. In contrast, in 2020 at the loamy sand location, there were four precipitation events across the season that exceeded 2.5 cm, and potato injury was as much as 60%. In 2020 the high amount of injury from flumioxazin was hypothesized to be caused by precipitation before herbicide application and not after, suggesting a need for more research in this area. This work documents the fine line between yield reduction presumably caused by reduced weed control and yield reduction assumed to be related to herbicide injury. This delineation between adequate weed control and consistent crop safety may differ by soil texture and environmental conditions, supporting the notion that custom-tailored weed management may become more necessary as high-precipitation events become more common in upper midwestern U.S. agricultural systems.
Weed management in carrot is challenging, given slow and inconsistent crop emergence and early-season growth and the lack of practical season-long management tools such as herbicides. We investigated holistic carrot production systems with a focus on minimizing inputs while optimizing resource use. In an overall sense, results of this work were consistent between years, and stark. The choice of carrot variety had a moderate influence on carrot foliar canopy development and, subsequently, weed density. For example, ‘Cupar’ carrot formed a complete crop canopy sooner than the other dicer-type ‘Canada’ variety. Likely as a result, density of weed species such as spotted ladysthumb and common lambsquarters was less where ‘Cupar’ was grown compared with where ‘Canada’ was grown. Gibberellic acid as a foliar application was not successful in these studies and, in a few cases, may have even increased weed-seed germination and establishment. Adding two carrot rows to the current regional industry-standard three-row bed system not only enhanced competitiveness with weeds but also improved carrot yield without additional fertilizer, water, or pest management inputs. By far, though, the most successful strategy to reduce weed density while maintaining or improving carrot yield was to delay seeding by 17 to 19 d. We anticipate more holistic production system research that integrates low-input alternatives in other crops as herbicide-resistant weeds proliferate while few new herbicides are developed. As was demonstrated in this research, such novel approaches can be successful without adding significant economic burden to the farmer or increasing risk of crop failure.
Introduction: Emergency care serves as an important health resource for First Nations (FN) persons. Previous reporting shows that FN persons visit emergency departments at almost double the rate of non-FN persons. Working collaboratively with FN partners, academic researchers and health authority staff, the objective of this study is to investigate FN emergency care patient visit statistics in Alberta over a five year period. Methods: Through a population-based retrospective cohort study for the period from April 1, 2012 to March 31, 2017, patient demographics and emergency care visit characteristics for status FN patients in Alberta were analyzed and compared to non-FN statistics. Frequencies and percentages (%) describe patients and visits by categorical variables (e.g., Canadian Triage Acuity Scale (CTAS)). Means and standard deviations (medians and interquartile ranges (IQR)) describe continuous variables (e.g., distances) as appropriate for the data distribution. These descriptions are repeated for the FN and non-FN populations, separately. Results: The data set contains 11,686,288 emergency facility visits by 3,024,491 unique persons. FN people make up 4.8% of unique patients and 9.4% of emergency care visits. FN persons live further from emergency facilities than their non-FN counterparts (FN median 6 km, IQR 1-24; vs. non-FN median 4 km, IQR 2-8). FN visits arrive more often by ground ambulance (15.3% vs. 10%). FN visits are more commonly triaged as less acute (59% CTAS levels 4 and 5, compared to non-FN 50.4%). More FN visits end in leaving without completing treatment (6.7% vs. 3.6%). FN visits are more often in the evening – 4:01pm to 12:00am (43.6% vs. 38.1%). Conclusion: In a collaborative validation session, FN Elders and health directors contextualized emergency care presentation in evenings and receiving less acute triage scores as related to difficulties accessing primary care. They explained presentation in evenings, arrival by ambulance, and leaving without completing treatment in terms of issues accessing transport to and from emergency facilities. Many factors interact to determine FN patients’ emergency care visit characteristics and outcomes. Further research needs to separate the impact of FN identity from factors such as reasons for visiting emergency facilities, distance traveled to care, and the size of facility where care is provided.
Augustes Comte first coined the term “altruism” as a cornerstone for his ethic doctrine Positivism, describing it as selfless concern for another’s welfare (Sutton, 1982). The existence of altruism and basic human kindness has been heavily debated throughout history, permeating through psychological, philosophical, and theological fields. Early philosophical and religious figures discussed concepts such Saint Augustine’s theory of conscience – that basic human kindness was an innate human feature (Fortin, 1996) – or Thomas Aquinas’ synderesis rule, which states that humans desire to be good and can innately distinguish between right and wrong (Davies, 2014). While these speculations have little or no empirical basis, they do have something in common with more recent research: they view altruism as having an innate component. Augustine and Aquinas attributed God as the innate origin of human altruism. Evolutionary psychologists view altruism as genetically influenced, having arisen, in part, from the Darwinian selective forces of natural and sexual selection.
Global inequity in access to and availability of essential mental health services is well recognized. The mental health treatment gap is approximately 50% in all countries, with up to 90% of people in the lowest-income countries lacking access to required mental health services. Increased investment in global mental health (GMH) has increased innovation in mental health service delivery in LMICs. Situational analyses in areas where mental health services and systems are poorly developed and resourced are essential when planning for research and implementation, however, little guidance is available to inform methodological approaches to conducting these types of studies. This scoping review provides an analysis of methodological approaches to situational analysis in GMH, including an assessment of the extent to which situational analyses include equity in study designs. It is intended as a resource that identifies current gaps and areas for future development in GMH. Formative research, including situational analysis, is an essential first step in conducting robust implementation research, an essential area of study in GMH that will help to promote improved availability of, access to and reach of mental health services for people living with mental illness in low- and middle-income countries (LMICs). While strong leadership in this field exists, there remain significant opportunities for enhanced research representing different LMICs and regions.
Linuron herbicide has been a mainstay of carrot weed management for years, but uncertainty around regulatory registration review and an increased prevalence of herbicide-resistant weeds have spurred interest in identifying alternatives that can be readily adopted in production. With this context in mind, herbicide programs were evaluated on a coarse-textured, low organic matter soil in 2015 and 2016. Season-long weed control without compromising yield was possible with weed management programs that included prometryn POST instead of linuron. With that said, a PRE herbicide such as pendimethalin was critical to establish an early-season competitive advantage for carrot plants over weeds, and careful attention should be paid to the prometryn rate, as selectivity is marginal. Carrot is often interseeded with a grain nurse crop to mitigate risk of wind erosion. Nurse crop injury was minimal where S-metolachlor, pendimethalin, or prometryn was applied at rates labeled for PRE use in carrot, with the exception of where prometryn was applied at rates above 1.1 kg ai ha−1.
The plethora of alternative food labels emerging in the marketplace reflects consumer interest in informed and sustainable purchasing. However, consumers’ preferences vary with respect to the sustainability metrics represented by labeling programs. The goal of this project was to characterize public university students’ perceptions of product parameters commonly represented by food labels for produce (e.g., cost, taste, certified organic, locally grown). A consumer survey (n = 338) was conducted at two university dining halls, located in close proximity to major residence hall communities which house approximately 2600 students. Culinary, health and cost attributes (taste, nutritional value, price and appearance) were ranked as more influential in determining purchasing decisions than sustainability attributes related to production and sourcing. While sustainability values were not as influential in driving purchasing behaviors as compared with product attributes, they were important to approximately 50% of the survey respondents. By identifying the sustainability values of students and their willingness to pay more for specific types of sustainable food, results from this study can inform efforts to align priorities of campus dining services with the values of their student patrons, as well as identify educational opportunities around agriculture and food production.
Economically solvent fresh-market potato production is predominantly dependent on the ability to efficiently produce consistent tuber quality and high yield, and the ability to meet first-to-market demand with early-season potatoes. Unfortunately, these two qualifiers often work against each other in terms of production management. In response, we studied integrated potato vine management programs that support timely early-season potato harvest. Vine management with a flail chopper, roller, and flame burner used alone or followed by diquat was evaluated when initiated 21 or 14 d prior to harvest in 2015 and 2016. Potato varieties included ‘Yukon Gold’ and ‘Dark Red Norland’. Potato leaf and stem management, as well as tuber skinning, stolon separation, grade, and yield were quantified. Among mechanical methods, potato leaf and stem management were poor when vines were rolled or mowed but better when flail chopped. In general, vine management and tuber skin set was better when treatments were initiated 21 d prior to harvest as opposed to 14 d. Vine management, tuber skin set, and yield were comparable when potato vines were flail chopped followed by flame burning and where diquat was applied twice, offering a viable program for smaller scale or organic production.
Soybean yield gain over the last century has been attributed to both genetic and agronomic improvements. Recent research has characterized how breeding efforts to improve yield gain have also secondarily impacted agronomic practices such as seeding rate, planting date, and fungicide use. To our knowledge, no research has characterized the relationship between weed–soybean interference and genetic yield gain. Therefore, the objectives of this research were to determine whether newer cultivars would consistently yield higher than older cultivars under increasingly competitive environments, and whether soybean breeding efforts over time have indirectly increased soybean competitiveness. Field research was conducted in 2014, 2015, and 2016 in which 40 maturity group (MG) II soybean cultivars released between 1928 and 2013 were grown season-long with three different densities of volunteer corn (0, 2.8, and 11.2 plants m−2). Soybean seed yield of newer cultivars was higher than older cultivars at each volunteer corn density (P<0.0001). Soybean seed yield was also higher in the weed-free treatment than at low or high volunteer corn seeding rates. However, soybean cultivar release year did not affect late-season volunteer corn shoot dry biomass at either seeding rate of 2.8 or 11.2 seeds m−2. The results indicate that while soybean breeding efforts have increased yield potential over time, they have not increased soybean competitiveness with volunteer corn. These results highlight the importance of other cultural practices such as planting date and crop row spacing for weed suppression in modern soybean production systems.
Slow carrot emergence and canopy development render the crop a poor competitor with weeds. In this study, the ability to suppress weeds and maintain yield in the presence of weeds was compared among nine carrot varieties that included those selected by plant breeders for rapid vegetative canopy development compared to traditional varieties. Two weed management treatments were compared: handweeding for 21 d after carrot seeding versus handweeding for the entire carrot season. In years and locations with low to moderate weed pressure, such as in the 2014 study, differences among carrot varieties in weed competitiveness or tolerance were less apparent and therefore less relevant. Maximum carrot yield loss to weed competition among varieties was 28% in 2014. Yield loss in the presence of weeds was 15% or less with six of the nine carrot varieties. However, when weed pressure was intense in the 2015 study, both carrot plant density and carrot canopy development were inversely related to weed biomass. Carrot yield loss in the presence of weeds ranged from 38 to 87%. Despite correcting seeding populations for differences in germination among carrot varieties, carrot stand establishment varied greatly and would likely affect subsequent weed control measures such as timely cultivation or herbicide application. Future research efforts are warranted that consider carrot stand establishment factors and their relationship with integrated weed management programs.
Five cultivation implements (two flex-tine cultivators, brush hoe, and rolling and shovel cultivators) were evaluated for weed control and effect on broccoli, snap bean, and sweet corn yield. Each implement was used alone or in combination with flex-tine cultivators. Standard broadcast herbicide treatments were: broccoli, metolachlor at 2.3 kg ai/ha posttransplant; snap bean, metolachlor preemergence (PRE) at 2.3 kg ai/ha followed by fomesafen postemergence (POST) at 0.4 kg ai/ha; sweet corn, atrazine at 1.1 kg ai/ha plus metolachlor at 2.3 kg ai/ha PRE. In the snap bean trials, an additional treatment consisted of metolachlor at 2.3 kg ai/ha PRE applied in a 25-cm band over the crop row followed by fomesafen POST at 0.4 kg ai/ha directed at the crop row, with a subsequent shovel cultivation. In the sweet corn trials, all cultivation treatments received an application of atrazine at 1.1 kg ai/ha plus metolachlor at 2.3 kg ai/ha PRE in a 25-cm band over the crop row. In broccoli, weed control and yields with all cultivation treatments were comparable to those with broadcast herbicide. In snap bean, flex-tine cultivators failed to control weeds and prevent yield reductions compared to the broadcast herbicide treatment. When either the brush hoe or the shovel cultivator was preceded by flex-tine cultivation, weed control and snap bean yield were comparable to those with broadcast herbicides. Banded herbicides followed by shovel cultivation also controlled weeds and prevented yield reductions. In sweet corn, banded herbicides controlled in-row weeds, and despite variable between-row weed control, all cultivation treatments yielded as well as the broadcast herbicide treatment. Relative performance of the cultivators was influenced by soil type and rainfall as well as crop canopy characteristics.
Red beet growers have expressed interest in adopting the microrate herbicide approach originally implemented in sugarbeet to achieve season-long weed management. Several red beet herbicides were first labeled for use in sugarbeet and lack substantial residual weed control. In response, red beet herbicide programs were evaluated that included a PRE application followed by up to three POST applications of various herbicide combinations. This research, however, indicated that herbicide programs that included PRE herbicides followed by as few as one or two POST applications that involve multiple active ingredients can provide season-long weed control. This observation was consistent across a broad spectrum of weeds, between two study locations that varied in soil type, and during two growing seasons. Herbicide programs that included only a PRE and six-leaf red beet growth stage application were successful at two locations in maintaining weed control and crop yield relative to hand-weeded red beet. Furthermore, these herbicide programs reduced the number of applications by 50% compared with the full programs, reducing crop injury risk and grower cost.
Field research was conducted to evaluate the effectiveness of herbicides and carrot mowing for swamp dodder control. Herbicide evaluation indicated the highest carrot yield and lowest crop injury with pendimethalin compared to the industry standard linuron. Swamp dodder control with pendimethalin was greater than 80% at 56 and 70 d after planting (DAP). Other herbicides controlled swamp dodder, but crop injury was unacceptable. Carrot yield was greater where pendimethalin or s-metolachlor was applied compared to all other herbicides. Carrot mowing once 72, 86, or 100 DAP and mowing twice (72 plus 100 DAP) reduced the percentage of carrots infected with swamp dodder. Carrot infection level was least when mowed 100 DAP, and mowing did not increase yield compared to the non-treated check. These results suggest that the integration of pendimethalin for early-season swamp dodder control, followed by mowing 100 DAP, could reduce the impact of swamp dodder on carrots.
Small broomrape is an annual, parasitic weed that was discovered recently in Oregon's red clover seed production system. Field experiments were conducted in 2002 and 2003 at two locations to evaluate 10 herbicide treatments applied after small broomrape emergence in red clover. Bentazon, bromoxynil, glyphosate, imazamox, imazamox plus bentazon, imazethapyr, MCPA, and pendimethalin were evaluated. Small broomrape density, small broomrape seed viability after treatment, and clover injury and seed yield were quantified. Small broomrape control with imazamox, glyphosate, and imazamox plus bentazon treatments was greater than the nontreated check in both years. However, imazamox and imazamox plus bentazon treatments were the only herbicide treatments that consistently exhibited a high level of crop safety, reduced small broomrape density, and did not reduce red clover yield. Herbicide treatments did not prevent production of viable small broomrape seeds. Future research is needed to develop control options that will prevent red clover yield loss and viable small broomrape seed production when applied before small broomrape emergence.
Experiments compared the effect on weed control and potato yield of banded applications of metolachlor plus linuron with or without flex-tine, rolling, and shovel cultivation prior to hilling. Cultivation without banded herbicide resulted in greater prehilling in- and between-row weed densities and reduced late-season weed control as compared to broadcast herbicides or cultivation with banded herbicides. Although the flex-tine and rolling cultivators were expected to provide improved in-row weed control, there were few differences between these and the other cultivation implements. Despite reduced weed control with cultivation alone, potato yields were not reduced.