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Professional turfgrass managers and consumers continue to express interest in low‐input turfgrasses; however, the potential reductions in maintenance inputs from "low‐input" turfgrasses are largely assumed and have not been well‐quantified. Over 3 years, replicated field experiments at Purdue University and the University of Minnesota quantified the performance and the amount of fertilizer and pesticide inputs of cool‐season turfgrass species when managed as variable‐input turfgrass systems. Fifteen turfgrass cultivars including eight cultivars across five taxa of fine fescue (Festuca spp.), two cultivars of tall fescue (Festuca arundinacea), four cultivars of Kentucky bluegrass (Poa pratensis), and one perennial ryegrass (Lolium perenne) cultivar were investigated. Cultivars were selected to represent advances in breeding efforts. Plots received no irrigation after establishment and individual plots only received fertilizer or pesticide inputs from 2019 to 2021 if the turf in the plot exceeded or fell below a set threshold (i.e., too many pests or too low turf density). Monthly data collection and fertilizer and pesticide inputs were recorded for 3 years at each site. New fine fescue taxa cultivars provided consistently higher turf quality at both sites and required an average 56% and 41% fewer fertilizer and pesticide inputs than traditional species (tall fescue, Kentucky bluegrass, and perennial ryegrass) in Indiana and Minnesota, respectively. Compared to traditional species, older Festuca rubra ssp. cultivars reduced fertilizer and pesticide inputs by an average of 37% and 25% in Indiana and Minnesota, respectively. Fine fescue taxa, especially new cultivars, are good choices to reduce inputs and provide high turf quality for low‐input turfgrass systems. Core Ideas: Improved fine fescue cultivars provided the highest turf quality in a variable‐input system.Fine fescue taxa required 37% fewer fertilizer and pesticide inputs than tall fescue.Kentucky bluegrass and perennial ryegrass required >50% more fertilizer and pesticide inputs than fine fescues.New Festuca rubra ssp. cultivars required 21%–31% fewer fertilizer and pesticide inputs than older cultivars, which still performed well.Research findings highlight the importance of proper species and cultivar selection based on site conditions, expectations, planned management strategies, and available inputs. [ABSTRACT FROM AUTHOR]

Green spaces comprising natural turfgrass are ubiquitous in urban areas globally and allow for a variety of ecosystem services that benefit nature and people. However, traditional natural turfgrass is often critiqued for the number of inputs (e.g., fertilizer, water) required to maintain it. With those critiques in mind, some cities have turned to artificial turf as an alternative groundcover despite environmental and human health concerns (e.g., heavy metal leaching, volatile organic compounds). Research of artificial turf has been minimal compared with that of the growth of installations, especially related to social aspects of the surface. The current research used an in-person experiential case study of park visitors in the Twin Cities Metropolitan Area of Minneapolis-St. Paul, MN, USA, to investigate how individuals perceived artificial turf compared with natural turfgrass as it relates to potential uses (e.g., resting/relaxing) and beliefs about sustainability (e.g., environmental impacts). Overall, participants preferred natural turfgrass across all uses but two (recreational and organized sports). The largest differences were observed for the use for picnic areas and the use for play areas for pets. Participants also perceived natural turfgrass as more sustainable than artificial turf, corresponding to the contribution to human health and well-being. In contrast, participants equally perceived the use of these surfaces in terms of natural resources. These findings have implications for public land managers, urban planners, city councils, and other stakeholders because they consider the adoption of artificial turf or other possible alternatives (e.g., low-input turfgrasses, bee lawns) to traditional turfgrass in the communities and their sustainability, maintenance, and cost-savings. [ABSTRACT FROM AUTHOR]

Turfgrass is often planted along roadsides because of its adaptability and capacity to perform a wide range of functions. Like other roadside vegetation, it must withstand a wide range of biotic and abiotic stresses while persisting long term with minimal management inputs. In cold‐weather climates, snow and ice management practices on roads include the use of deicing salts. Deicing salts can have negative impacts on infrastructure and the environment including soil structure degradation, surface and ground water contamination, and reduction of vegetation quality along roadsides. Insights from past evaluations of turfgrass response to stresses experienced on roadsides can provide perspective for future approaches. This review provides historical context for the establishment of turfgrasses as roadside vegetation in cold‐weather climates where deicing salts are used. Adaptability of species for roadside applications as well as field and controlled environment evaluations of salt tolerance are discussed. In future studies, improved characterization of roadside stress and broader collaborative evaluation programs can enhance testing and result in improved specifications for roadside turfgrass species and mixtures. [ABSTRACT FROM AUTHOR]

Fine fescues, taxa within the Festuca genus, are considered some of the most shade‐tolerant cool‐season turfgrasses, but past research from field studies has been inconsistent. The objective of this research was to evaluate variation in Chewings fescue (Festuca rubra L. ssp. commutata Gaudin, CH), hard fescue (F. brevipila Tracey, HD), and strong creeping red fescue (F. rubra ssp. rubra Gaudin, ST) morphology and physiology under simulated foliar shade and full sun. Experiments were carried out using 12 CH, 13 HD, and 15 ST entries within a greenhouse with or without a photoselective filter to simulate foliar shade. The filter reduced the red to far‐red (R/FR) ratio to ∼0.66, and light intensity was reduced to 30% of full sun under shade treatment. Several parameters were assessed including height, the number of tillers, biomass, total chlorophyll, and the chlorophyll a/b ratio. In both sun and shade experiments, ST were significantly taller than the other taxa. Chewings fescue and HD had significantly more tillers than ST in sun, but both CH and ST had significantly more tillers than HD in shade. Hard fescue had the greatest biomass in sun, and the least in shade. Significantly more CH genotypes lacked shade avoidance responses (SAR) than both other taxa under shade, and a greater proportion of HD were shade intolerant. Based on this study, CH > ST > HD in terms of improved response to shade. However, variation for response to shade observed within entries indicates potential for future improvement. [ABSTRACT FROM AUTHOR]

Increasing temperatures associated with climate change will be the next challenge for crop improvement, especially for turfgrass species that are often grown in urban green spaces. Previous research on turfgrass heat stress tolerance has been limited to a small number of species and cultivars with different heat stress conditions between studies; therefore, we assessed heat stress tolerance of 34 turfgrasses representing 14 species. Four replicates of each entry were established for at least 12 wk and then subjected to 49 d of heat stress (35/25 °C day/night) followed by a 4 wk recovery period (25/15 °C day/night). Turfgrass entries were assessed using the normalized difference vegetative index, the percentage of green obtained with digital image analysis, and membrane stability estimated by electrolyte leakage. Buffalograss [Bouteloua dactyloides (Nutt.) J.T. Columbus], Kentucky bluegrass (Poa pratensis L.), tall fescue [Schedonorus arundinaceus (Schreb.) Dumort], and slender creeping red fescue (Festuca rubra ssp. littoralis) were more tolerant of heat stress than the other species. The Canada bluegrass (Poa compressa L.), blue grama [Bouteloua gracilis (Willd. ex Kunth.) Lag. ex Griffiths], and smooth brome (Bromus inermis Leyss.) cultivars were all tolerant of heat stress; however, only one cultivar for these three species was tested, making species‐wide generalizations difficult. In some cases, the cultivars and/or selections within a given species differed in heat stress response. Almost all entries were able to recover from the heat stress by the end of the recovery period. Altogether, we were able to identify turfgrasses that should perform adequately in high‐temperature urban environments. [ABSTRACT FROM AUTHOR]

The article discusses the relation of the fungal endophyte Epichloe festucae var. lolii to the freezing tolerance of perennial ryegrass (Lolium perenne L.). Topics include the importance of winter hardiness for perennial ryegrass, the use of non-isogenic hosts in research, and genetically differing populations of perennial ryegrass.

The article presents a study on alternative management options for multiyear perennial ryegrass seed production in Northern Minnesota. Topics include the use of plant growth regulators (PGRs) and fall residue management, such as open burning, baling, and mowing, to achieve multiyear seed production in northern climates.

We are grateful to Stefanie Grüne and Andrew Chignell for their thoughtful commentaries on our paper. Both focus their remarks on the issue of ‘givenness,’ which could seem like a relatively narrow topic within the much broader subject matter of cognition that we have attempted to describe in our paper. However, we think that givenness, properly understood, plays an important role in Kant’s account of cognition, since it is central to both of the conditions that Kant places on cognition (which we call the ‘givenness condition’ and the ‘thought condition’). In particular, we maintain that givenness is an independent condition on cognition, one that has a meaning and function distinct from what it contributes to the thought condition. Full consideration of the givenness condition allows one to see more clearly how it gives expression to one of Kant’s most fundamental concerns in the first Critique. For, in our view, the primary role of givenness is to help to explain how it is that representations can refer, or fail to refer, to objects in a specific, cognitively significant way, an achievement that Kant is marking with the term ‘cognition.’ To make good on these claims and to substantiate this picture of the broader significance of givenness within Kant’s account of cognition, we address Grüne’s paper first, then Chignell’s. [ABSTRACT FROM AUTHOR]

In this paper, we offer an overview of the basic structure of Kant’s account of cognition, of the conditions on the notion of cognition most central to the first Critique, and how they are satisfied in the case of human beings. Our primary aim in this regard is to provide a comprehensive (albeit not exhaustive) framework for understanding Kant’s account of (theoretical) cognition. In the course of doing so, we argue for various interpretative claims, which, taken together, amount to a novel understanding of Kant’s account of cognition. First, we argue that cognition is a mental state that determines a given object by attributing general features to it. Second, we explain what it means for Kant for an object to be given: givenness in the relevant sense involves an immediate relation to an existing object. These first two claims imply that cognition (Erkenntnis) is distinct from knowledge (Wissen), both in Kant’s sense and in our modern sense. Third, we note some fundamental ambiguities about what sensibility and understanding are, and point out that purely causal interpretations of these faculties are problematic. Fourth, we distinguish between an intuition and an intuitive representation (analogous to the distinction between a concept and a discursive representation) in such a way that an intuition is one specific kind of intuitive representation. Fifth, we describe two different accounts of concepts (‘logical’ and ‘psychological’) and explain how they complement each other (despite their distinctness). Sixth, we diagnose several confusions regarding whether Kant is or is not a non-conceptualist about intuitions (though without attempting a definitive resolution to that debate). Finally, we show how our analysis of cognition clarifies what the most promising lines of argument are for Kant’s claim that we cannot have cognition of the objects of traditional metaphysics (while still allowing for limited kinds of knowledge of things in themselves). [ABSTRACT FROM AUTHOR]

In Minnesota, most lawns and higher cut turfgrass areas consist primarily of species such as kentucky bluegrass (Poa pratensis L.) and perennial ryegrass (Lolium perenne L.) that require significant management inputs such as frequent mowing and nitrogen fertility. Several studies have shown that other species have the potential to be used more widely on home lawns in Minnesota; however, little is known about the management requirements of these species. In this study, we evaluated the performance of several alternative grass species under varying mowing and nitrogen fertility regimes at two sites in Minnesota in 2010 and 2011. Hard fescue [Festuca trachyphylla (Hackel) Krajina] showed the most consistent performance across management regimes, seasons, and locations. Colonial bentgrass (Agrostis tenuis Sibth.) showed good spring and fall turf quality, but suffered from excess thatch development and disease incidence. 'Barkoel' prairie junegrass [Koeleria macrantha (Ledeb.) Schult] maintained acceptable turf cover throughout the trial, whereas unimproved native prairie junegrass populations did poorly regardless of management level. Tufted hairgrass [Deschampsia cespitosa (L.) P. Beauv.] did not perform consistently in the trial due to summer stress. Our results show that hard fescue, colonial bentgrass, and 'Barkoel' prairie junegrass performed well regardless of mowing height or fertility treatment and could be used to a greater degree as low-input turfgrasses in Minnesota. [ABSTRACT FROM AUTHOR]

In this paper I argue that Kant's complex argument against materialism involves not only his generic commitment to the existence of non-spatio-temporal and thus non-material things in themselves (which follows directly from Transcendental Idealism), but also considerations pertaining to reason and the subject of our thoughts. Specifically, I argue that because Kant conceives of reason in such a way that it demands a commitment to the existence of the unconditioned so that we can account for whatever conditioned objects we encounter in experience, our thoughts, which are also conditioned, require something unconditioned that, because it is unconditioned, cannot be material. In this way, Kant's attitude towards materialism is based not only on abstract features of his metaphysics and epistemology, but also on specific features that were under serious discussion in the early modern period. [ABSTRACT FROM AUTHOR]

Seeding rates (SRs) and row-spacing widths (RSWs) in perennial ryegrass (Lolium perenne L.) seed production are variable and the impacts of these factors on perennial ryegrass seed yield and plant growth characteristics are not well characterized. Experiments were conducted during 2010 and 2011 in first-year seed production fields near Roseau and Roosevelt, MN, where five SRs (1.3, 2.6, 5.2, 7.8, and 10.4 kg pure live seed [PLS] ha−1), three RSWs (10, 20, and 30 cm), and three N rates (67, 112, and 157 kg N ha−1) were evaluated in a split-split plot design under nonirrigated conditions. The 30-cm RSW resulted in 45% greater stem rust incidence, 8% fewer fertile tillers, and up to 2% greater 1000-seed weight (TSW) vs. the 10-cm RSW. For every unit of N applied, N increased biomass by 4 to 25 kg ha−1, fertile tillers by 3.7 tillers m−2, and seed yield by up to 4.7 kg seed ha−1, depending on environment. The 7.8 and 10.4 kg PLS ha−1 SRs combined with the 10-cm RSW, 157 ha−1 N rate, and other management factors, nearly eliminated weeds (<2% weed cover) compared with with wider RSWs and lower SRs. Weed cover was always inversely correlated with early-season vegetative cover (EVC). Seeding rates of 2.6 kg PLS ha−1 and greater resulted in similar seed yields suggesting that early-season plant density is not as important for seed yield as other management factors such as N rate, which significantly improved seed yield in three environments.

US Gulf of Mexico ports alone accounted for 80 per cent of the total--a massive US$160 billion of investment--much of it aimed at attracting the new cargoes due to come through the Panama Canal. All of this investment has paid off as more and more cargo has been diverted away from the US west coast ports and through the Panama Canal to destinations along the Gulf of Mexico that are closer to shippers' target markets. No longer must a shipment enter the US via Los Angeles or Seattle or any other west coast port. [Extracted from the article]

Abstract: It is well known that during his pre-Critical period, Kant was a major proponent of Newtonian physics, for the project of the Universal Natural History explicitly uses “Newtonian principles” to explain the formation of the various bodies that constitute our solar system as well as those that lie beyond. What has not been widely noted, however, is that the early Kant also developed a major criticism of Newton, one that is based on subtle metaphysical issues pertaining to God, which are most at home in philosophical theology. Interestingly, this criticism is neither an inchoate precursor of his later criticisms of Newton’s account of absolute space, nor isolated to the abstract realm of metaphysics, but has a wide range of implications for the way in which a scientific account of the formation and constitution of the heavenly bodies ought to be developed, that is, for the kind of argument Newton offered in the Principia. That Kant remained interested in this set of issues later in his Critical period suggests that, alongside the revolutionary changes that comprise transcendental idealism, there are deep continuities not only in his Newtonian commitments, but in his anti-Newtonian tendencies as well. [Copyright &y& Elsevier]

The article compares the philosophical views of American philosopher Wilfrid Sellars and South African philosopher John McDowell to those of German philosopher Immanuel Kant. Specific attention is placed on the "myth of the given," a concept from Sellars that deals with sense data and criticizes the theory that knowledge of what is perceived is independent of the conceptual processes which create perception. Other topics covered include sensations, cognition, and epistemology.

Prairie junegrass [Koeleria macrantha (Ledeb.) Shultes] is a perennial, shortgrass prairie species distributed throughout the Northern Hemisphere that is being evaluated for use as a low-input turf. In June 2007, 300 genotypes representing collection locations derived from Colorado, Nebraska, and Minnesota germplasm were grown and evaluated 3 years for turfgrass performance characteristics in a randomized complete block design with five clonal replications at two locations (St. Paul, MN, and Becker, MN). After establishment, plots received no supplemental irrigation or fertility and were mowed weekly to a height of 6.4 cm. Broad-sense heritability estimates were calculated on a clonal mean (Hc) and single-plant (Hsp) basis for turf quality (Hc = 0.62, Hsp = 0.13), crown density (Hc = 0.55, Hsp = 0.09), mowing quality (Hc = 0.59, Hsp = 0.09), and genetic color (Hc = 0.45, Hsp = 0.06). The heritability estimates indicate that selection for these traits should result in significant gains in germplasm improvement. Differences were observed in the means and variances among clones, collection locations, and/or collection regions for many of the traits evaluated including rust severity (Puccinia spp.), spring green-up, plant height, lateral spread, vertical regrowth, and flowering traits. The positive correlations among some of these traits and those with moderate heritability estimates should allow for multi-trait selection in cultivar development. [ABSTRACT FROM AUTHOR]

Roadside vegetation is subject to significant salt stress as a result of runoff water and road de-icing practices in cold weather climates. Salt-tolerant turfgrass can play a role in maintaining roadsides that are both functional and sustainable. As such, the objective of this research was to evaluate the differential salt tolerance of turfgrass cultivars that may be suitable for roadside establishment. Three replications of 75 cool-season turfgrass cultivars were established in a randomized complete block design at two locations: Roselawn Cemetery (Roseville, MN, USA) and MnROAD research facility (Albertville, MN, USA). Plots were seeded during August and September of 2010. Visual ratings of establishment were collected throughout the fall, and survival was evaluated visually in spring 2011. Numerous cultivars of perennial ryegrass (Lolium perenne L.) established best at all locations in the fall; however, winter survival varied by location. Cultivars of alkaligrass (Puccinellia spp.), including ‘Fults,’ ‘Salty,’ ‘Oceania,’ and ‘Salton Sea,’ performed best at Albertville. ‘Shoreline’ slender creeping red fescue (Festuca rubra L. ssp. litoralis), ‘Navigator’ strong creeping red fescue (Festuca rubra L. ssp. rubra), and an advanced population of sheep fescue (Festuca ovina L.) from the University of Minnesota turfgrass breeding program were among the most salt tolerant at Roseville. Site-dependent performance and effective salt tolerance of cultivars from numerous species indicate that a carefully chosen mix will be best for establishment and maintenance of high-quality roadsides. [ABSTRACT FROM PUBLISHER]

Prairie junegrass [Koeleria macrantha (Ledeb.) Shultes] is a perennial, short-grass prairie species distributed throughout the Northern Hemisphere. This species demonstrates tolerance to many environmental stresses in Minnesota. Forty-eight K. macrantha accessions from the United States National Plant Germplasm System (NPGS) were grown under low-input conditions to evaluate turfgrass quality characteristics for use in a breeding program. A second objective was to identify key geographical locations for germplasm collection. The experiment was conducted at Becker and St. Paul, MN. Nineteen accessions at Becker and 30 accessions at St. Paul performed with an adequate turf quality rating of 5.0 or higher when averaged over the 3-yr study, suggesting the potential for use in low-input areas. Prairie junegrass from northern collection regions displayed the highest spring green-up ratings, an important turf trait in northern climates. There was a negative correlation between this trait and mowing quality at Becker (r = -0.44) and at St. Paul (r = -0.34). Several accessions had acceptable mowing quality and would be candidates for integration into a native prairie junegrass turfgrass breeding program. There was no correlation between inflorescence emergence and turf quality, or between inflorescence emergence and persistent straw suggesting that flowering does not necessarily affect turf quality ratings. Rust (unknown Puccinia species) was present at both locations. [ABSTRACT FROM AUTHOR]

Prairie junegrass [Koeleria macrantha (Ledeb.) Shult.] is a perennial, short-grass prairie species distributed throughout the northern hemisphere. This species is known to require fewer inputs than other cool-season turfgrasses and it demonstrates tolerance to many environmental stresses found in Minnesota. In June 2007, 48 K. macrantha accessions from the U.S. National Plant Germplasm System (NPGS) were grown and evaluated for seed production characteristics in 2 locations (St. Paul, MN, and Becker, MN). Significant variation was found among accessions for several seed production traits including harvest date, plant height, seedhead number, and seed yield. A significant correlation between seedhead number and seed yield was found, which can be utilized for indirect selection in the production nursery. Plant growth and seed yield were highest at the Becker location, demonstrating the species' preference for welldrained soils. Flowering times were significantly different between the locations; however, there were no significant differences in the duration from seedhead emergence to harvest between the locations. Multivariate analysis did not reveal clustering of accessions based on geographic origin, suggesting a diversity of material within collection regions. [ABSTRACT FROM AUTHOR]

As restrictions on water use, fertilization, and pesticide applications continue to increase, golf course superintendents will need to use grass species that require reduced inputs. The objective of this study was to evaluate alternative turfgrass species under low-input fairways conditions. In 2005, 17 species were established on native soil in St. Paul, MN. Each species was evaluated at three levels of traffic (zero, three, or six passes per week using a drum-type traffic simulator) and two mowing heights (1.90 and 2.54 cm). Data collected included turfgrass quality and percent living stand density. In 2006, velvet bentgrass (Agrostis canina L.), colonial bentgrass (Agrostis capillaris L.), and creeping bentgrass (Agrostis stolonifera L.) maintained acceptable quality in all treatment combinations. In 2007, Chewings fescue (Festuca rubra L. ssp.fallax) and sheep fescue (Festuca ovina L.) were the top-performing species regardless of treatment. Hard fescue (Festuca brevipila Tracey) performed poorly in Year 1 and well in Year 2. All other species did not perform at an acceptable level during the study. The results of this study indicate that sheep fescue, Chewings fescue, colonial bentgrass, and velvet bentgrass should be studied further for use on low-input golf course fairways in the northern United States. [ABSTRACT FROM AUTHOR]

Sellars and McDowell, among others, attribute a prominent role to the Myth of the Given. In this paper, I suggest that they have in mind two different versions of the Myth of the Given and I argue that Kant is not the target of one version and, though explicitly under attack from the other, has resources sufficient to mount a satisfactory response. What is essential to this response is a proper understanding of (empirical) concepts as involving unifying functions that can take sensations as input and deliver normative representations as outputs. By understanding concepts in this way, one need not, as the second version of the Myth of the Given maintains, take sensations to be both natural and normative. Instead, they can be understood as the natural effects of external objects on us, but natural effects that can nonetheless play a role in a normative process because the concepts that are responsible for the normativity of the results can require that such natural effects be present as inputs into the process. [ABSTRACT FROM AUTHOR]

Many winter stresses affect the ability of a perennial grass to overwinter in cold, temperate climates. Freezing tolerance is one of the major component traits affecting winterhardiness. Although effective freezing tolerance assessment procedures have long been available for perennial ryegrass ( Lolium perenne L.), no work has been done to characterize plant collections in the United States that may possess novel variation for freezing tolerance and winterhardiness. In this study, 21 accessions sampled from a larger set of 300 accessions with known winterhardiness and 3 check varieties were subjected to environmentally-controlled, low temperature acclimation, followed by controlled freezing using a programmable laboratory freezer. Eight freezing treatments from −2 to −16°C were used to determine survival across the known spectrum of freezing tolerance in perennial ryegrass. LT50 values were estimated based on whole plant survival, as well as tiller survival at each of the temperature treatments in the evaluation. LT50 values for the accessions and checks ranged from −10.31 to −13.95°C, with 3 accessions possessing significantly greater freezing tolerance than the most freeze-tolerant check, ‘NK200’. LT50 values were well correlated with winterhardiness in St. Paul during the winters of 2004–2005 and 2005–2006. Lower LT50 values in this experiment were associated with greater spring growth following the stressful winter of 2004–2005 and upright growth habit. The lack of negative biological association between freezing tolerance and turf quality components indicates that freezing tolerance testing could be a useful tool in breeding and selection with landrace germplasm. [ABSTRACT FROM AUTHOR]

The lack of winterhardiness of some cool-season grasses limit their usefulness in northern climates. Perennial ryegrass (Lolium perenne L.) lacks winterhardiness in Minnesota but has desirable qualities, such as wear tolerance and rapid establishment, that are useful in many turf applications. While domesticated germplasm may lack winterhardiness, undomesticated wild or landrace germplasm may have genes for better winterhardiness in environments like Minnesota's. In 2004, 300 accessions from two public sources in the USA were planted with eight check varieties and populations in two environments in central Minnesota, St. Paul and Becker. Thirty individuals of each accession were evaluated for seedling vigor and tiller survival after the first winter. Other turf-quality traits and tiller survival after the second winter were evaluated on those plants that survived the first winter. The first winter was extremely harsh and resulted in the death of all accessions and checks at Becker. There was good differentiation among accessions at St. Paul for tiller survival, with 8 of the 300 accessions performing better than NK200, the most winterhardy check variety. The second winter was considerably less harsh, with less death of tillers and whole plants. While the accessions do not have suitable turf quality for direct domestication, turf quality can be improved through breeding. [ABSTRACT FROM AUTHOR]

The primary limitation of tufted hairgrass [Deschampsia cespitosa (L.) P. Beauv.] as a turfgrass appears to be damage caused by billbug (Sphenophorus spp.) herbivory, in this study several sets of germplasm were used in volatile collection studies. Whole-plant volatile collections were made on: i) untreated plants, ii) plants that had been treated with jasmonic acid (JA), and iii) plants that had experienced mechanical damage. In untreated plants, intraspecific differences were found for the amount of hexenyl acetate that was released; this compound has been shown to be involved in important plant volatile-insect interactions. Application of JA resulted in a dramatic increase in the production of monoterpenes, which are known to attract predators of insect pests. (Z)- β-ocimene comprised nearly 9% of the total volatile profile after JA treatment, but was not detected in untreated plants. Mechanical damage of tufted hairgrass plants led to an increased release of characteristic green leaf volatiles such as 3-hexen-1-ol as well as hexenyl acetate. Mechanical damage changed the components of the volatile profile, but the results were quite different from JA treatment. It would be of interest to determine if the selection of tufted hairgrass germplasm that produces high and sustained levels of monoterpenes, in response to JA, would attract sufficient insect predators to make this an effective breeding strategy for insect resistance. [ABSTRACT FROM AUTHOR]

Focuses on the notion of autonomy in philosophy. Nature of autonomy; Conditions and requirements for autonomy; Views of philosopher Karl Ameriks in his work "Kant and the Fate of Autonomy".

Examines the model and views of causality by philosopher Immanuel Kant and the philosophy of physics and nature. Claims of the philosopher for having adequate responses and arguments in comparison to the position of philosopher David Hume; Issue of causality with reference to the book "Second Analogy of Experience," by the philosopher; Principle of continuity, asymmetry, and activity as well as the uniformity of nature.

Recently, turfgrass breeders have developed many improved turf-type tall fescue (Festuca arundinacea Schreb.) cultivars. Due to the large number of cultivars currently available to turfgrass managers and researchers, we have classified turf-type tall fescue cultivars into six groups based primarily on several morphological measurements. This type of classification is important for turfgrass breeders because many breeding decisions are made based on observations in a spaced-plant nursery. The major objective of this study was to classify tall fescue cultivars and selections based on spaced-plant measurements and to then compare those results with turf performance. A spaced-plant nursery consisting of 36 cultivars and selections was established in September 1998 at Adelphia, N.J. Plant height, panicle length, flag leaf width and length, subtending leaf width and length, and subtending internode length were measured 10 days after anthesis in 1999 and 2000. Additionally, a turf trial was established at North Brunswick, N.J., that included the same 36 cultivars and selections. The turf plots were evaluated for several traits including overall turf grass quality, density, and susceptibility to brown patch disease. Based on principal component analysis of morphological measurements, along with turf trial data, all cultivars and selections were assigned to one of six groups: forage, early-standard, standard, early semi-dwarf, semi-dwarf, and dwarf. In turf plots, the semi-dwarf, early-semi dwarf, and dwarf groups were the top-performing types in terms of overall turfgrass quality, and the forage and early-standard cultivars had the lowest overall quality ratings. The dwarf types did not perform well under summer stress, especially in terms of brown patch disease incidence. The results of this study suggest that when developing cultivars for higher maintenance situations, turf-type tall fescue breeders should focus on the development of semi-dwarf... [ABSTRACT FROM AUTHOR]

This paper considers Kant’s conception of force and causality in his early pre-Critical writings, arguing that this conception is best understood by way of contrast with his immediate predecessors, such as Christian Wolff, Alexander Baumgarten, Georg Friedrich Meier, Martin Knutzen, and Christian August Crusius, and in terms of the scientific context of natural philosophy at the time. Accordingly, in the True estimation Kant conceives of force in terms of activity rather than in terms of specific effects, such as motion (as unnamed Wolffians had done). Kant’s explicit arguments in the Nova dilucidatio for physical influx (in the guise of the principle of succession) are directed primarily against the conception of grounds and existence held by Wolff, Baumgarten, and Meier, and only secondarily against Leibniz (by asserting the priority of bodies over mind rather than vice versa). Finally, Kant’s reconciliation of the infinite divisibility of space and the unity of monads in the Physical monadology is designed to respond to objections that could be raised naturally by Wolff and Baumgarten. [Copyright &y& Elsevier]

Focuses on the argumentative structure of Imanuel Kant's `Metaphysical Foundations of Natural Science.' Establishment of three conditions that a body of knowledge must satisfy in order to be considered science proper; Distinguishing of two different parts of the metaphysics of nature; Distinction between a transcendental and a special metaphysics of nature; Aim to justify Newtonian science.

Focuses on philosopher Immanuel Kant's views regarding theoretical proofs of the existence of God. Views from Kant's books `Critique of Pure Reason' and `The Only Possible Argument in Support of a Demonstration of the Existence of God'; Relegation of God to the status of a regulative principle; Kant's justification for rejecting his pre-critical period argument for God's existence.

Focuses on the difficulty that arises in the context of Immanuel Kant's justification of the laws of mechanics. Status of the laws of motion in early 18th century Germany; First law of mechanics; Third law of mechanics; Action at a distance; Intelligibility of Kant's justification in the context of his rationalistic background.

Focuses on the United States' policy in the Middle East which is characterized by an increasing bias for Israel and open hostility to `uncooperative' regimes like Iraq. Main goals of American Middle East policy; United States' strained relations with its allies in the region; Negative implications for United States' policy goal of secure oil supply; United States' neglect of public opinion in the region.

Examines how the Pre-established Harmony doctrine of mathematician Gottfried Wilhelm von Leibniz was received in Germany during the 18th century. Views of Leibniz on the doctrine; Modifications made by Leibniz's German advocate Christian Wolff to the doctrine; Development of the Physical Influx as an alternative to the Pre-established Harmony doctrine.

Compares Issac Newton's law of motion and Immanuel Kant's law of mechanics. Differences between the laws; Information on metaphysics; Overview of physics textbooks; Discussion on the laws.

Focuses on the development of the Physical Influx theory from 1732 to 1745 in the writings of Johann Christoph Gottsched, Martin Knutzen, and August Friedrich Crusius. Gottsched's version of Physical Influx; Martin Knutzen's treatment of Physical Influx and Pre-established Harmony; Argument from impenetrability; Argument from the simplicity of divine action on others.

Background: Neutral density shade cloth is commonly used for simulating foliar shade, in which it reduces light intensity without altering spectral quality. However, foliar shade also alters spectral quality, reducing the ratio of red to far-red (R:FR) light, altering the ratio of blue to green (B:G) light, and reducing ultraviolet light. Unlike shade cloth, photoselective filters can alter spectral quality, but the filters used in previous literature have not simulated foliar shade well. We examined the spectral quality of sunlight under color temperature blue (CTB), plus green (PG), and neutral density (ND) filters from LEE Filters, Rosco e-colour + and Cinegel brands either alone or layered, hypothesizing that the contrasting filter qualities would improve simulations. As a proof-of-concept, we collected spectral data under foliar shade to compare to data collected under photoselective filters. Results: Under foliar shade reductions in the R:FR ratio ranged from 0.11 to 0.54 (~ 1.18 in full sun), while reductions in the B:G ratio were as low as 0.53 in deep shade, or were as high as 1.11 in moderate shade (~ 0.87 in full sun). Neutral density filters led to near-neutral reductions in photosynthetically active radiation and reduced the R:FR ratio similar to foliar shade. Color temperature blue filters simulated the increased B:G ratio observed under moderate foliar shade, but did not reduce the R:FR ratio low enough. On their own, PG filters did not simulate any type of foliar shade. Different brands of the same filter type also had disparate effects on spectral quality. Layered CTB and ND filters improved the accuracy of moderate foliar shade simulations, and layering CTB, PG, and ND filters led to accurate simulations of deep foliar shade. Conclusions: Layering photoselective filters with contrasting effects on the spectral quality of sunlight results in more accurate simulations of foliar shade compared to when these filters are used separately. Layered filters can re-create the spectral motifs of moderate and deep foliar shade; they could be used to simulate shade scenarios found in different cropping systems. Photoselective filters offer numerous advantages over neutral density shade cloth and could be a direct replacement for researchers currently using neutral density shade cloth. [ABSTRACT FROM AUTHOR]

Hard fescue is an allo‐hexaploid, caespitose, cool‐season grass that is part of the fine‐leaved ovina complex of the Lolium–Festuca clade in Poaceae. It is predominantly used as a low‐maintenance turfgrass and soil stabilization grass in situations with reduced inputs of nitrogen and water. While often recommended for use under tree canopies, prolonged foliar shade can thin turf stands and reduce their functionality; furthermore, gray snow mold caused by Typhula incarnata can further affect hard fescue turfgrass functionality. In this study, we gathered a diverse population of hard fescue collections and varieties, which fit into four genetic structures. Because no genomic reference sequences exist for this species, a contig‐level pseudohaploid genomic reference was assembled from a plant of the hard fescue variety Beacon. With 98% benchmarking universal single‐copy orthologs (BUSCO) coverage from 241 contigs, this reference assembly was used to conduct genome‐wide association analysis. Thirty‐eight single‐nucleotide polymorphism (SNP) markers were associated with foliar shade response phenotypes, including SNPs near molybdate transporter and cytochrome P450 genes. Three SNP markers were associated with gray snow mold responses, with one located near a Protein Kinase G11 gene and corresponding to a 20% improvement in gray snow mold resistance. Core Ideas: A primary contig‐level genome of Beacon hard fescue was assembled.A GWAS for shade tolerance resulted in 38 significant loci, with some loci shared among traits.A GWAS for gray snow mold resistance found three loci, two of which were near candidate genes [ABSTRACT FROM AUTHOR]

Important financial savings, along with reductions in environmental impact, can be achieved by planting lawns with low-input turfgrass species. Drawing on data from an online survey, this article provides empirical evidence on the factors that influence consumers' willingness to adopt low-input turfgrasses. We group consumers into two segments: Willing Adopters and Reluctant Homeowners. Regardless of segment, consumers who regard maintenance requirements as more important were more willing to adopt low-input turfgrasses, whereas those who placed a higher value on appearance, were more unlikely to change to a low-input turfgrass, especially for Reluctant Homeowners. We categorized the barriers to adoption as follows: 1) Promotion, 2) Benefits and Accessibility, 3) Peer Effect, 4) Sample, and 5) Information. Our models predict that consumers' willingness to adopt low-input turfgrass can be significantly increased if the identified barriers are removed. Based on our study, suppliers/retailers should adopt heterogeneous and multiple marketing strategies, such as promoting through multiple channels, informing and advising the public on proper information, providing photos or exhibiting in-store samples, triggering communication between different types of consumers, and providing incentives and improving accessibility, to target different consumer groups. [ABSTRACT FROM AUTHOR]

Turf‐type perennial ryegrass (Lolium perenne L.) success depends on adequate turfgrass quality and economical seed yield. In most breeding programs, spaced plants are the initial unit of selection in which observations of related individuals dictate the selection of superior germplasm for further testing. Therefore, spaced plants must be predictive of seed production and turfgrass growing environments. This study investigated the effectiveness of standard (three plants m−2) and competitive (23 plants m−2) spaced‐plant nurseries as selection environments with respect to two sward environments as well as applying a novel image analysis technique for several key traits. Seed production, turfgrass, and the two spaced‐plant growing environments were tested at two locations in Minnesota. Turfgrass quality traits were measured in 2017 and 2018 and seed production traits were measured in 2018. Automated image analysis was able to predict the traditional visual scoring values at both locations for crown rust (Puccinia coronata f.sp. lolii) severity [Pearson's correlation (rp) > 0.79, P <.001], winter injury (rp > 0.89, P <.001), and turfgrass texture (rp > 0.88, P <.001). Increasing the competition among spaced plants altered the plant phenotype and improved accuracy for vegetative biomass, crown rust severity, seed yield, and, at one location, turfgrass quality. There was no benefit of increasing competition for several traits such as genetic color, fertile tillers, and spikelet number. Although the competitive design was not useful for all traits, pragmatically, the competitive design used less space and often made measurements and observations easier for bunch‐type grasses. [ABSTRACT FROM AUTHOR]

Background: Inflorescence properties such length, spikelet number, and their spatial distribution across the rachis, are fundamental indicators of seed productivity in grasses and have been a target of selection throughout domestication and crop improvement. However, quantifying such complex morphology is laborious, time-consuming, and commonly limited to human-perceived traits. These limitations can be exacerbated by unfavorable trait correlations between inflorescence architecture and seed yield that can be unconsciously selected for. Computer vision offers an alternative to conventional phenotyping, enabling higher throughput and reducing subjectivity. These approaches provide valuable insights into the determinants of seed yield, and thus, aid breeding decisions. Results: Here, we described SpykProps, an inexpensive Python-based imaging system to quantify morphological properties in unilateral inflorescences, that was developed and tested on images of perennial grass (Lolium perenne L.) spikes. SpykProps is able to rapidly and accurately identify spikes (RMSE < 1), estimate their length (R2 = 0.96), and number of spikelets (R2 = 0.61). It also quantifies color and shape from hundreds of interacting descriptors that are accurate predictors of architectural and agronomic traits such as seed yield potential (R2 = 0.94), rachis weight (R2 = 0.83), and seed shattering (R2 = 0.85). Conclusions: SpykProps is an open-source platform to characterize inflorescence architecture in a wide range of grasses. This imaging tool generates conventional and latent traits that can be used to better characterize developmental and agronomic traits associated with inflorescence architecture, and has applications in fields that include breeding, physiology, evolution, and development biology. [ABSTRACT FROM AUTHOR]