International Turfgrass Society Research Journal最新文献

Pollination is fundamental to healthy ecosystems, and global pollination services have been valued at over $200 billion annually. However, landscape fragmentation, urban growth, and ecosystem degradation adversely influence insect pollinator biodiversity. Efforts to mitigate these factors must be enhanced in order to establish and increase pollinator populations. As such, a better understanding of the landscapes that make up their habitats may help mitigate these negative effects. Gauging the effect of landscapes on pollinators requires identification of insect richness and abundance, but studies that evaluate trapping and netting methodology over established turfgrass–forb habitat are scant. Here, we present preliminary findings from a single location (Starkville, MS) regarding the effectiveness of two sampling methodologies, netting, and pan traps. Methods were compared over bermudagrass (Cynodon dactylon) mixed with white clover (Trifolium repens). The total abundance, taxa abundance, and the link between insect taxa and method were examined. Netting was found to be more effective at catching pollinators, especially those belonging to the Apidae and Syrphidae families. Apidae and Syrphidae were the most abundant families present. Halictidae showed higher abundance in pan traps, however, no significant difference in abundance was found between it and other families. Ongoing work seeks to identify all samples to species level. The work presented here has been replicated at another site and will be combined with this study to enable broader inferences.

Late summer and autumn application of nitrogen (N) to bermudagrass (Cynodon spp.) in the transition zone has been associated with enhanced turfgrass color but has been thought to increase the potential for winter injury. Eleven N sources were applied in late summer and early autumn to provide a total annual N level of 98 kg ha⁻¹ in Olathe, KS to evaluate fall color and spring green coverage of ‘Riviera’ bermudagrass [Cynodon dactylon (L.) Pers.]. Treatments included experimental coated urea fertilizers, N sources containing urease inhibitors, urea, and nontreated turfgrass. Significant winter injury occurred throughout the experimental area. Turfgrass color in late October was positively correlated with green coverage evaluated in May (r = .55; P < .001). For example, bermudagrass treated with AND3.0EX (Poly/Humic Coated Urea) had a color rating of 3.5 (1 to 9 scale; 9 = dark green) in late October, and green coverage in May was 44%. Nontreated turfgrass had a color rating of 1.5 in late October, and green coverage in May was 8%. Enhanced winter survival of bermudagrass following late-season N application may require that turfgrass managers rethink traditional N programs limiting application to only late spring and midsummer dates in the transition zone.

Growing sports turf in a stadium can be a challenge for greenkeepers. The desire to reduce impact of weather conditions during sporting events and to increase human comfort has led to the development of semi- or fully closed stadia, resulting in significant shade for the turf pitch. Light reduction becomes a limiting factor for the growth of turfgrass leading to decreased quality and wear tolerance of the playing surfaces. Thereby the use of lighting in stadia is more and more common and is now considered as a requirement to maintain high-quality playing surfaces. Most stadia use conventional high-pressure sodium (HPS) technology as artificial lighting. Lighting is used in stadia to improve turf in low-light conditions by allowing accelerated regrowth of the turf, through the optimization of photosynthesis. However, these HPS lamps are very energy intensive and not sustainable. Therefore, more and more stadia have chosen to go into light-emitting diode (LED) lighting. This study was performed to determine the effects of artificial lighting (HPS and LED) on turf quality, turf density, and wear tolerance of different cool-seasons grass species used for sports fields under shaded conditions. This experiment showed that (a) rough meadow-grass (Poa trivialis) significantly thrives in shade, and (b) HPS and LED lighting sources yielded similar results for all turfgrass species investigated. Thereby, our results suggest that artificial lighting can significantly improve cool-season turfgrass under shade for turf quality, turf density, and wear tolerance.

As urbanization in the world increases, irrigated landscapes have become common in the developing world, particularly the temperate and warm regions. Although these landscapes provide esthetic value, they can also consume resources such as potable water. In the United States, this consumption of water for a discretionary use has come into focus as water supplies continue to become limited. This reality will affect landscapes and the use of turfgrass in the future. There are several strategies that are likely to be used in future landscapes, such as smaller irrigated areas, less irrigated turfgrass, mandates on water-efficient irrigation technology, irrigation water budgets, new drought-resistant breeds, increased use of organic soil amendments, rainwater harvesting, and alternative water sources.

Understanding the comparative evapotranspiration (ET) rates of commonly used turfgrass species in a shaded environment would improve irrigation scheduling recommendations and contribute towards urban water conservation. The objectives of this study were (a) to compare the ET rates of selected turfgrasses under two irradiance levels and (b) to determine if shade-induced changes in ET rates were related to changes in leaf morphology. An 8-wk greenhouse experiment was conducted in fall 2017 with ‘Latitude 36 Turf Bermudagrass’ hybrid bermudagrass [Cynodon dactylon (L.) Pers. × Cynodon Transvaalensis Burtt Davy], ‘Falcon IV’ tall fescue [Schedonorus arundinaceus (Schreb.)] ‘Dumort., nom. cons.’, and ‘Meyer’ Japanese lawngrass (Zoysia japonica Steud.) grown in lysimeters 15 cm in diameter. Plants were subjected to shaded conditions (55% nominal shade fabric) or a control (ambient greenhouse conditions plus supplemental lights). Plants were evaluated for specific leaf area, clipping yield, and ET rate over the study period. Turfgrass ET rates for tall fescue, Japanese lawngrass, and hybrid bermudagrass declined under shade by 12.8, 23.1, and 28.9%, suggesting that the ET rate for tall fescue is less sensitive to changes in light intensity. These results suggest irrigation scheduling methods for shaded landscapes may be influenced by species response to changes in light intensity.

Increasing urban growth has placed a strain on limited potable water resources. Therefore, improved drought tolerance in turfgrass is important to reduce the need for supplemental irrigation to maintain the aesthetic value and functionality of turfgrass areas. Field evaluations are subject to variability in irrigation patterns, wind, soil, and drainage patterns within an experimental area. The objectives were to evaluate the effect of polyethylene glycol (PEG) on root and shoot production in species of Zoysia and determine if PEG is suitable for screening genotypes for drought responses. Two experiments were conducted, each arranged as a randomized complete block design. Experiments used plants grown in conetainers with and without PEG in hydroponic culture. Plants were evaluated for root length density, root surface area, root diameter, leaf mass, leaf wilting, and turfgrass quality. The PEG treatment produced minimal differences. The results indicated that higher PEG concentrations are needed to elucidate drought responses and observe differential drought responses among zoysiagrasses.