Water use by turfgrasses is important because it impacts land use decisions and the potential use of natural turfgrasses in enclosed stadia due to humidity levels and fan comfort. The application of exogenous abscisic acid (ABA) has been shown to reduce evapotranspiration (ET) and photosynthetic rates of plants. This study aimed to examine the impact of foliar ABA application on Kentucky bluegrass (KBG; Poa pratensis ) ET and photosynthetic rates. In addition, water use efficiency (WUE), turfgrass growth, and percent green cover before and after application were also measured. The application of ABA reduced KBG ET and photosynthetic rates by 19.2% and 18.2%, respectively, while also reducing turfgrass growth and greenness. Photosynthetic rates returned to normal during recovery periods, whereas ET rates did not return to pre‐drought levels. The response of ET and photosynthetic rates did not provide a consistent response, although WUE was reduced immediately after ABA application. These findings show reductions in ET rates that could affect conditions in indoor stadia, which may provide insight for turfgrass maintenance of indoor stadia with turfgrasses.

The No Mow May and Leave The Leaves social media campaigns, both of which advocate for a minimalist approach to turf management in various settings including home lawns, parks, and urban greenspaces, have gained momentum in the public consciousness. No Mow May encourages homeowners and municipalities to refrain from mowing the grass in May, and Leave The Leaves recommends refraining from raking and removing fallen tree leaves in the autumn. The underlying goal is to support biodiversity, particularly pollinators, by either allowing wildflowers to flourish or providing an overwintering habitat for insects and other small creatures. This study examined each of these campaigns and the combination of both on turf quality and weed establishment. By avoiding lawn mowing until June, the unintended consequences were increased weed invasion and decreased turf quality. Regardless of Leaf treatment, flower number did not differ between mowed and unmowed treatments except when counting immediately followed mowing. Thick leaf litter over turf in the winter led to turf death followed by weed invasion. The challenges we observed associated with No Mow May and Leave The Leaves initiatives could be addressed by integrating science-backed practices and considering regional variations in climate and grass species. This would ensure that both environmental conservation and turf health are considered.

Vrn-A1 (VERNALIZATION A1) and Fr-A2 (FROST RESISTANCE A2) have been associated with variation in winter survival of wheat (Triticum aestivum L.). The beneficial alleles of Vrn-A1 and Fr-A2 are largely fixed in Canadian winter wheat germplasm, rendering the associated molecular markers ineffective for marker-assisted selection (MAS) in elite populations. The objectives were to (i) identify quantitative trait loci (QTLs) for winter survival in eastern Canada and determine their usefulness for MAS and (ii) explore the underlying genetic mechanisms of superior winter survival in the region. A subpopulation (n = 321) of the Canadian Winter Wheat Diversity Panel, consisting of genotypes that were fixed for the beneficial alleles of vrn-A1 and Fr-A2, was previously evaluated for winter survival in three eastern Canadian environments (Elora 2016-2017, CÉROM 2017-2018, and Elora 2017-2018). Genome-wide association mapping identified three significant QTLs for winter survival, a previously identified QTL on chromosome 5A, and two novel QTLs on chromosomes 5D and 7B. These QTLs were of low-to-moderate marker utility (0.1473-0.4796) and conferred a 0.7%-1.8% increase in mean winter survival. In silico analyses revealed that an array of biotic and abiotic stress responses are implicated in winter survival in eastern Canada, which challenges the notion that lethal temperature is the primary cause of winterkill in some regions. As significant winterkill events are sporadic in the region, it may be beneficial to identify individual components of winter survival that can be examined in artificial environments.

Low-temperature flooding and ice encasement (LTFIE) cause variable survival of winter wheat ( Triticum aestivum L.) in Ontario, which limits the adoption of wheat into crop rotations by growers. The development of novel cultivars capable of withstanding LTFIE is a promising avenue for improvement, but the methods used to assess the survival of winter wheat under LTFIE are restricted. This study developed updated methods to determine the survival of wheat cultivars under LTFIE using controlled environments and, to our knowledge, is the first method since the 1980s to use Canadian eastern soft red winter wheat (CESRW) to conduct cold tolerance studies. Chamber-acclimated plants of AC Carberry (spring wheat control), Branson (CESRW), CM614 (CESRW), and Norstar (hardy Canadian western red winter control) cultivars were used to estimate the days (LD50) and temperature (LT50) to reach 50% mortality under ice and without ice treatments. Norstar had the longest LD50 at 33 days, Branson and CM614 had similar LD50 of 18 and 20 days, and AC Carberry did not reach an LD50 as it died early in both treatments. The LT50 of each cultivar was different; Norstar had the lowest LT50 (−13.6 °C day 0 and −13.2 °C day 7), and AC Carberry had the highest LT50 (−6.6 °C day 0 and −2.7 °C day 7). The detailed methods developed in this study were more reliable compared to older methods based on the more accurate reported LD50 and LT50 of the cultivars, therefore, these methods can be used to screen winter cereals for LTFIE in the future.

The turfgrass industry supports golf courses, sports fields, and the landscaping and lawn care industries worldwide. Identifying the problem spots in turfgrass is crucial for targeted remediation for turfgrass treatment. There have been attempts to create vehicle- or drone-based scanners to predict turfgrass quality; however, these methods often have issues associated with high costs and/or a lack of accuracy due to using colour rather than grass height (R2 = 0.30 to 0.90). The new vehicle-mounted turfgrass scanner system developed in this study allows for faster data collection and a more accurate representation of turfgrass quality compared to currently available methods while being affordable and reliable. The Gryphon Turf Canopy Scanner (GTCS), a low-cost one-dimensional LiDAR array, was used to scan turfgrass and provide information about grass height, density, and homogeneity. Tests were carried out over three months in 2021, with ground-truthing taken during the same period. When utilizing non-linear regression, the system could predict the percent bare of a field (R2 = 0.47, root mean square error < 0.5 mm) with an increase in accuracy of 8% compared to the random forest metric. The potential environmental impact of this technology is vast, as a more targeted approach to remediation would reduce water, fertilizer, and herbicide usage.

Plant growth regulators (PGRs) are commonly used to manage turfgrass growth on golf courses. Growing degree day (GDD) models predict the need for reapplication of PGRs, such as trinexapac-ethyl (TE) resulting in a potential loss of regulation. Optimal GDD models for application of prohexadione calcium (PC), a late-stage gibberellin inhibitor, on fairway-height turfgrasses are currently unknown. The effect of PC and TE on plant growth and stand health were evaluated in two separate seasons on mixed stands of creeping bentgrass (Agrostis stolonifera L.) and annual bluegrass (Poa annua L.) maintained at 9-mm height at the Guelph Turfgrass Institute. Five treatments (control, PC 2.8 g 100 m(-2) [0.09 oz 1000 ft(-2)], PC 5.6 g 100 m(-2) [0.18 oz 1000 ft(-2)], PC 8.4 g 100 m(-2) [0.27 oz 1000 ft(-2)], and TE 8.0 mL 100 m(-2) [0.26 fl oz 1000 ft(-2)]) were applied based on a label rate GDD schedule. Plant clipping dry weight (DW), visual color ratings and normalized difference vegetative index (NDVI) were assessed. Most PC and TE treatments effectively reduced DW and had a positive effect on visual color and NDVI. A relationship was observed between PC application rates, suggesting that higher application rates allow for greater regulation of plant growth. Rebound effects or periods of excess growth, occurred when reapplication intervals exceeded 350 GDD and had an average of thermal time greater than 21.0 GDD over a 10-day period. Using optimal GDD models for PC will assist in the effective regulation of turfgrass growth and improved stand health.

The urgency of addressing the climate crisis has heightened the need to make sustainable decisions. Universities and research institutions are uniquely able to help develop and disseminate useful information for industry, specifically small and medium enterprises. This case study examines the collaboration between the Guelph Turfgrass Institute (GTI) and the turfgrass industry that culminated in the creation of a "Turf Net Present Value Model". This model enables turfgrass installers, managers, and local municipalities to determine the structure of their turfgrass systems, natural or artificial, and estimate the net present value (NPV) over an extended period. A conceptual model for effective industry-university collaboration is then used to evaluate the knowledge transfer between academia and industry, showcasing a knowledge-transfer framework for improved decision-making and sustainability in sports facilities.

The development and improvement of crop cultivars are necessary to meet the demands of the growing global population. The ability to decrease the generation time is imperative for breeders to achieve higher rates of genetic gain annually. Understanding the way in which photoperiod affects the maturation rate of these crops, including winter wheat ( Triticum aestivum L.), is required for decreasing generation time in breeding programs. The effects of prolonged photoperiod and light intensity on winter wheat generation time were studied to determine if photoperiod may contribute to a shortened cycle time. Three winter wheat cultivars (Branson, CFBA1401, and Norstar) and one spring wheat cultivar (AC Carberry) were exposed to four treatments based on the daily light integral (DLI): high light (HL) or low light and photoperiod as follows: 22 h of light and 2 h of dark (22:2) or 16 h of light and 8 h of dark (16:8). Generation time, as measured by days to maturity in the HL22:2 treatment, resulted in a decrease of 8 days or 7% of the total generation time, compared to the control, HL16:8 treatment. Photoperiod itself had a minimal effect on generation time when both DLI and temperature were controlled. An improved understanding of the effects of photoperiod, thermal time, and DLI and their interactions is required prior to implementation in a winter cereal breeding program.

Evaluating the effectiveness of fertilizers on crops without traditional yield is difficult, as clipping collection is time-consuming and not indicative of the desired response to the fertilizer. Remote sensing techniques, like the normalized difference vegetation index (NDVI), have emerged as an effective tool to combat these issues. Canopy reflectance, measured by NDVI, is commonly used to differentiate turfgrass response to nitrogen (N) fertilization treatments; however, advancements in data processing are needed for greater differentiation between treatments and better testing of the effects of fertilizer responses. Presented here is an advancement in the processing of NDVI data by applying a compound exponential (pulse peak) function to changes in NDVI over time, relative to a control. This method’s effectiveness in differentiating between fertilizers was evaluated by applying polymer-coated urea (PCU), an enhanced efficiency fertilizer (EEF), and urea on turfgrass to show the usefulness of the novel curve fitting in highlighting differences in fertilizer response. The field study was carried out on an established Kentucky bluegrass (Poa pratensis L.) blend on a sandy loam soil rootzone maintained with a typical home lawn maintenance regime. Ratios of PCU to urea ranging from 100% urea to 100% PCU with increments of 20% of PCU were used to observe a continuum of response between the two fertilizer types. The N rate for all blends was 73 kg ha−1, with unfertilized plots used as a control to set baseline measurements for the curve fitting. Turfgrass response to N fertilization treatments was assessed through visual turfgrass quality ratings, dry matter yield, and canopy reflectance, where higher urea content resulted in the shortest time to maximum ∆NDVI (24 days), while 100% EEF reached maximum ∆NDVI at 56 days. The novel curve fitting analysis of the NDVI data allowed for differentiation between treatments, provided a measure of fertilizer effects, and differentiated between urea and enhanced efficiency fertilizers.

The presence of urban plants in an ecosystem are vital for processes including carbon sequestration and the type of urban plants included in urban settings affect the amount of carbon sequestered. The objective of this study is to assess the ability of urban plants to sequester carbon under a number of available management practices through the development and refinement of an accessible carbon calculator. Available urban plant data were analyzed using the calculator developed using available literature regarding carbon sequestration to determine differences between different types of plants, when hidden carbon costs (HCC) were considered. Carbon sequestration including HCC for turfgrasses could be calculated but there was a lack of information regarding HCC of urban trees and shrubs. The calculator was shown to be an effective tool for homeowners to determine viable management practices to maintain or increase carbon sequestration.

The yield of a pasture is directly proportional to the amount of light plants intercept and allocate to different organs. When plants are carbon (C) limited, due to defoliation, they allocate more C preferentially to shoots to restore leaf area. In contrast, water and nitrogen (N) limitations lead to a greater allocation of C to roots. Changes in the root:shoot ratio therefore reflect changes in C and N partitioning and indicate their relative priority. A major factor that influences plant responses to stress is their ability to store and remobilise reserves to restore leaf area. Species with tap roots, like lucerne, have a large potential C and N storage capacity that is utilised seasonally for storage and remobilisation. This has been used to develop seasonally based grazing management rules. Similarly, recommendations to graze perennial ryegrass at the 2- or 3-leaf stage are based on the balance between maximizing growth rates and the need to replenish water-soluble carbohydrate reserves. However, perennial ryegrass has lower levels of perennial reserves than other grass species. This reduces its resilience to concurrent water deficits or N deficiency. Under these conditions maintaining the recommended 3-leaf grazing intervals and/or leaving higher post-grazing pasture masses are recommended to assist canopy recovery. Other grass species, such as cocksfoot and tall fescue, provide more resilience, particularly in response to water deficits.

Cereal crops including maize (Zea mays L.) are inhabited by non-disease causing microbes known as endophytes that can promote plant growth, aid in host nutrient acquisition and promote host pathogen resistance. Screening endophytes for beneficial traits in planta using large, slow-growing cereals is challenging, thus a rapid but relevant in planta system is needed. Here, we propose that turfgrasses can be used as high-throughput assay systems for screening cereal microbes for beneficial nutrient traits. Turfgrasses are genetic relatives of cereals, but small with fast growth rates; they can be grown in test tubes under sterile conditions on defined media. Five turfgrass genotypes were evaluated for traits ideal for assaying endophytes with nutrient acquisition traits. Based on these criteria, annual ryegrass (Lolium multiflorum) was selected as a high-throughput assay system. Annual ryegrass was then used to test a collection of maize endophytes for their ability to promote plant biomass in the absence of nitrogen. Out of 75 bacterial endophytes tested, one strain (an Enterobacter sp) consistently promoted root and shoot biomass. We discuss the potential of annual ryegrass as a model assay system to test cereal endophytes for acquisition of various nutrients, changes in root/shoot architecture as well as anti-pathogen traits.

Water‐use restrictions during the summer of 2016 in Guelph, ON, Canada, prevented the irrigation of natural turf soccer fields and provided a unique opportunity to study the effects on soil volumetric water content and surface hardness on actively used youth soccer fields. Soil volumetric water content and surface hardness were tested on a weekly basis from July through September 2016. Areas of the turf that became brown were compared with the areas that remained green. Surface hardness within areas of brown turfgrass cover frequently exceeded 100 g (level of concern for player safety) even though soil volumetric water content was similar between the areas of green and brown turfgrass cover. Therefore, irrigation of sports fields during times of drought is recommended to preserve the cushioning effect of green turfgrass cover.

On golf courses planted to creeping bentgrass, invasion of annual bluegrass is a constant concern. To analyze if nitrogen fertilization manipulation could bias growth to creeping bentgrass, both grasses were fertilized either through foliar or soil application with either urea or ammonium sulfate and the impact on shoot and root growth measured. Ammonium sulfate resulted in greater overall growth for both species. Foliar application resulted in greater shoot growth for annual bluegrass and soil application resulted in greater root growth for creeping bentgrass. Leaf samples, as well as multiple leaf samples collected from golf courses, were examined microscopically for potential routes for foliar nutrient uptake: stomata and aqueous pores. No statistical difference was observed in the stomatal number between the two species but annual bluegrass possessed more aqueous pores. The enhanced ability of annual bluegrass to benefit from foliar fertilization may aid in its encroachment on highly managed golf greens.

AimsThe aim of this study was to determine if endophytes from wild and ancient Zea plants (corn family) have anti-fungal activities, specifically against the most important fungal pathogen (Sclerotinia homoeocarpa) of creeping bentgrass, a relative of Zea, used here as a model grass.Methods and ResultsA library of 190 bacterial endophytes from wild, ancient and modern Zea plants were tested for their ability to suppress S.homoeocarpa invitro, followed by in planta testing of candidates using greenhouse trials. Three endophytes could suppress S.homoeocarpa, originating from wild maize and an ancient Mexican landrace, consistent with our hypothesis. 16S phylogenetic analysis and BOX-PCR DNA fingerprinting suggest that the anti-fungal endophytes are distinct strains of Burkholderia gladioli. One strain (3A12) was confirmed to colonize creeping bentgrass using green fluorescent protein (GFP) tagging. Evans blue vitality staining demonstrated that the bacterial endophytes exhibited fungicidal activities against the pathogen. The endophytes inhibited a wide spectrum of plant-associated fungi including diverse crop pathogens.ConclusionsThe results support the hypothesis that wild and ancient Zea genotypes host bacterial endophytes that can control fungal pathogen(s).Significance and Impact of the StudyThese results suggest that wild and ancient crops may be an unexplored reservoir of anti-fungal bacterial endophytes.

Background: Endophytes are microbes that inhabit internal plant tissues without causing disease. Plant microbial communities consist of large numbers of endophyte species. Understanding the functions of these endophytes is a major challenge. An important function of some endophytes is to suppress fungal pathogens. Typically, plant associated microbes are screened for anti-fungal activities in vitro using the high-throughput dual culture screen, but it is not clear whether this method correlates with the activities of these microbes in planta. Furthermore, it is not clear whether in vitro screening captures all of the microbes that show this activity inside plants. The objective of this study was to evaluate the relevance of the in vitro dual culture method for screening endophytes with anti-fungal activity.Results: In parallel, 190 bacterial endophytes from the corn grass family (Zea) were screened for suppression of two fungal pathogens (Sclerotinia homoeocarpa and Rhizoctonia solani) using the in vitro dual culture method, and in planta using the model plant, creeping bentgrass. All endophytes that showed anti-fungal activity in planta against Sclerotinia homoeocarpa and Rhizoctonia solani (3 or 4 strains, respectively, out of 190), were captured in vitro. The in vitro and in planta screening results strongly correlated (r = 0.81 and r = 0.94 for the two pathogens, respectively).Conclusions: Evidence was gained here that the in vitro dual culture method is a relevant method for high throughput screening of plant endophyte communities for anti-fungal activity. In our study, the method captured all of the microbes that suppressed the corresponding pathogens in planta.